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1
Garrett, J. H., and A. Jain. "Encore: an object-oriented knowledge-based system for transformer design." Artificial Intelligence for Engineering Design, Analysis and Manufacturing 2, no. 2 (May 1988): 123–34. http://dx.doi.org/10.1017/s0890060400000603.
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The design of electronic power transformers is an activity that requires the application of well-established algorithms from electromagnetic theory and heuristic, judgmental techniques derived from experience in the design and manufacturing of these devices. This paper describes an object-oriented knowledge-based system, Encore, that was developed at Houston Downhole Sensors (a division of Schlumberger Well Services). Encore combines object-oriented, rule-based, and procedural programming techniques to design 60 Hz power transformers. The system uses a heuristic search strategy to generate design alternatives, and then selects the “best” design based on size and efficiency considerations The heuristics are represented and applied as rules; the electromagnetic components are modelled as frame-like objects. The object-oriented nature of this system facilitated enhancements; by specializing some of the objects comprising a power transformer, a power inductor model was quickly developed. Encore reduces design time from a couple of days to less than an hour; it is being used to design the transformers and inductors of power supplies in new Schlumberger well-logging tools. The system was implemented on a Xerox interlisp Workstation using an object-oriented environment called STROBE.
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Xu, Xiangkai, Zhejun Feng, Changqing Cao, Mengyuan Li, Jin Wu, Zengyan Wu, Yajie Shang, and Shubing Ye. "An Improved Swin Transformer-Based Model for Remote Sensing Object Detection and Instance Segmentation." Remote Sensing 13, no. 23 (November 25, 2021): 4779. http://dx.doi.org/10.3390/rs13234779.
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Remote sensing image object detection and instance segmentation are widely valued research fields. A convolutional neural network (CNN) has shown defects in the object detection of remote sensing images. In recent years, the number of studies on transformer-based models increased, and these studies achieved good results. However, transformers still suffer from poor small object detection and unsatisfactory edge detail segmentation. In order to solve these problems, we improved the Swin transformer based on the advantages of transformers and CNNs, and designed a local perception Swin transformer (LPSW) backbone to enhance the local perception of the network and to improve the detection accuracy of small-scale objects. We also designed a spatial attention interleaved execution cascade (SAIEC) network framework, which helped to strengthen the segmentation accuracy of the network. Due to the lack of remote sensing mask datasets, the MRS-1800 remote sensing mask dataset was created. Finally, we combined the proposed backbone with the new network framework and conducted experiments on this MRS-1800 dataset. Compared with the Swin transformer, the proposed model improved the mask AP by 1.7%, mask APS by 3.6%, AP by 1.1% and APS by 4.6%, demonstrating its effectiveness and feasibility.
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IASINSKII, IGOR' F., and DENIS V. EGOROV. "DESIGN AUTOMATION OF INTERNAL ISOLATION OF HIGH VOLTAGE TRANSFORMERS INPUT USING PARALLEL COMPUTING." Cherepovets State University Bulletin 4, no. 97 (2020): 89–101. http://dx.doi.org/10.23859/1994-0637-2020-4-97-8.
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The design process of a transformer is characterized by conflicting requirements for its qualities. This circumstance is due to the fact that the transformer includes a large number of elements and is manufactured on individually tuned equipment. Moreover, the production of transformers is associated with the cost of such valuable materials as copper, aluminum, steel, etc. Thus, the transformer is a complex system, the high-quality design of which is difficult without automation. It is proposed to speed up the process of calculating the internal isolation of a transformer using a parallel computing environment and the use of fast algorithms. Methods of mathematical modeling of physical objects, methods of applied mathematics, principles of computer modeling of physical objects, algorithms for parallelizing the computing process in interfaces with shared memory, analysis of the results of computational experiments are applied. A software system has been developed for the automated design of the internal isolation of the high-voltage input of the transformer...
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Junaid, Mohd Wasiuddin. "Image Captioning with Face Recognition using Transformers." International Journal for Research in Applied Science and Engineering Technology 10, no. 1 (January 31, 2022): 1426–32. http://dx.doi.org/10.22214/ijraset.2022.40057.
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Abstract: The process of generating text from images is called Image Captioning. It not only requires the recognition of the object and the scene but the ability to analyze the state and identify the relationship among these objects. Therefore image captioning integrates the field of computer vision and natural language processing. Thus we introduces a novel image captioning model which is capable of recognizing human faces in an given image using transformer model. The proposed Faster R-CNN-Transformer model architecture comprises of feature extraction from images, extraction of semantic keywords from captions, and encoder-decoder transformers. Faster-RCNN is implemented for face recognition and features are extracted from images using InceptionV3 . The model aims to identify and recognizes the known faces in the images. The Faster R-CNN module creates the bounding box across the face which helps in better interpretation of an image and caption. The dataset used in this model has images with celebrity faces and caption with celebrity names included within itself, respectively has in total 232 celebrities. Due to small size of dataset, we have augmented images and added 100 images with their corresponding captions to increase the size of vocabulary for our model. The BLEU and METEOR scores were generated to evaluate the accuracy/quality of generated captions. Keywords: Image Captioning, Faster R-CNN , Transformers, Bleu score, Meteor score.
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Trần, Ngọc Thạch, Thanh Phương Nguyễn, Trọng Huy Nguyễn, and Đình Anh Khôi Phạm. "A new method in determination of electrical parameters and geometrical structure of a power transformer applicable to failure diagnosis." Science & Technology Development Journal - Engineering and Technology 3, no. 4 (December 27, 2020): first. http://dx.doi.org/10.32508/stdjet.v3i4.744.
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In transmission and distribution networks throughout the world and in Vietnam nowadays, power transformers that are operating in the networks often are in black-box condition, i.e. there is no internal information available in terms of geometrical structure and material parameters. Geometrical structure of power transformers includes mainly winding structure and additional parts such as a static end ring or a would-in shield coil, if any whereas main materials in power transformers consists of conductive, insulating and magnetic materials… This makes difficulties in faults diagnosis that is based on the approach of physical modeling in general and the so-called electrical equivalentcircuit based modeling in particular since the physical approach requires internal information of power transformers for calculating electrical parameters. In case the electrical equivalent-circuit approach is used, the diagnosis is then conducted based on the change of values of electrical parameters in the circuit before and after an alarm or a suspicious fault that happens when power transformers are in operation. Relevant international investigations conducted recently have mainly focused on test objects as power transformers in grey- or white-box condition, i.e. during manufacturing phase, since they have available geometrical structure and material properties. To show a possibility that blackbox power transformers could be investigated in a physical manner, this article introduces a new method in determining electrical parameters and geometrical structure applied on a black-box power transformer. The research is based on the Frequency Response Analysis technique and has developed recent relevant investigations of the authors. This enables investigations of the value change of electrical equivalent parameters of this transformer on its simulated frequency responses for the purpose of physical fault diagnosis of power transformers later on.
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Kryukov, A. V., and I. A. Lyubchenko. "Improving the quality of electricity supply systems in stationary objects of railway transport." Power engineering: research, equipment, technology 23, no. 6 (March 30, 2022): 53–65. http://dx.doi.org/10.30724/1998-9903-2021-23-6-53-65.
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THE PURPOSE. Development of a methodology for modeling the modes of power supply systems for railways equipped with devices to improve the quality of electricity in the networks supplying stationary objects of railway transport. Two design solutions were considered that ensure the reduction of unbalance and voltage deviations on the 0,4 kV buses of substations supplying these objects. The first of them was based on the use of suction transformers, and the second - on the use of lines with a grounded phase.METHODS. The studies were carried out using the Fazonord software package, which provides complex modeling in phase coordinates of the modes of power supply systems.RESULTS. The results obtained made it possible to draw the following conclusions: when using suction transformers, which were included in the rail cut, the average value of the unbalance coefficient in negative sequence on the 0.4 kV buses of the object's substation decreased by 2,5% compared to the absence of such devices; in the presence of transformers, which were included in the return wire, this indicator decreased by 19%. The use of lines with a grounded phase instead of a two-wire-rail line made it possible to improve the quality of electricity on 0.4 kV buses, while the maximum of the unbalance coefficient in the negative sequence was reduced by 40%.CONCLUSION. On the basis of computer modeling, it is shown that the use of suction transformers with a return wire and 25 kV lines with a grounded phase makes it possible to improve the quality of the electric power industry in the power supply systems of stationary objects of railway transport.
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Rahimpour, Ebrahim, and Stefan Tenbohlen. "Fault diagnosis of actual large-power high-voltage windings using transfer function method." Archives of Electrical Engineering 60, no. 3 (September 1, 2011): 269–81. http://dx.doi.org/10.2478/v10171-011-0025-4.
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Fault diagnosis of actual large-power high-voltage windings using transfer function method The transfer function (TF) method is presently a well-known method used to detect various types of winding damage in power transformers. Although abundant research has been done on this subject using laboratory windings as test objects, it is hard to find one, whose test objects are actual large-power transformer windings. Hence, a 400 kV disc winding consisting of 86 discs is used in this paper to study turn-to-turn short circuit with the help of the TF method. To evaluate the effects of this type of fault on TF curves, some mathematical comparison algorithms are used in this research.
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Makasheva, Svetlana Igorevna, and Pavel Sergeevich Pinchukov. "Development of «CHROMATIC» program for assessment of condition of traction transformers." Transport of the Urals, no. 4 (2021): 114–19. http://dx.doi.org/10.20291/1815-9400-2021-4-114-119.
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The paper deals with the urgent problem of preventing failures of oil-filled railways equipment by means of non-destructive methods of diagnostics and early detection of pre-failure conditions. A computer program based on dissolved gas analysis for assessing and predicting the power transformer’s state was proposed and registered. The objects of the study are traction substation’s transformers located on the Far Eastern Railway of Russia. The dissolved gases concentration has been analyzed for an eight-year observation period. The problem of the state of oil insulation predicting is solved by Gaussian distribution applying. The developed software can be used at the digital traction substations as the predictive analytic block, which corresponds to the current digitalization trend.
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Panboonyuen, Teerapong, Sittinun Thongbai, Weerachai Wongweeranimit, Phisan Santitamnont, Kittiwan Suphan, and Chaiyut Charoenphon. "Object Detection of Road Assets Using Transformer-Based YOLOX with Feature Pyramid Decoder on Thai Highway Panorama." Information 13, no. 1 (December 25, 2021): 5. http://dx.doi.org/10.3390/info13010005.
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Due to the various sizes of each object, such as kilometer stones, detection is still a challenge, and it directly impacts the accuracy of these object counts. Transformers have demonstrated impressive results in various natural language processing (NLP) and image processing tasks due to long-range modeling dependencies. This paper aims to propose an exceeding you only look once (YOLO) series with two contributions: (i) We propose to employ a pre-training objective to gain the original visual tokens based on the image patches on road asset images. By utilizing pre-training Vision Transformer (ViT) as a backbone, we immediately fine-tune the model weights on downstream tasks by joining task layers upon the pre-trained encoder. (ii) We apply Feature Pyramid Network (FPN) decoder designs to our deep learning network to learn the importance of different input features instead of simply summing up or concatenating, which may cause feature mismatch and performance degradation. Conclusively, our proposed method (Transformer-Based YOLOX with FPN) learns very general representations of objects. It significantly outperforms other state-of-the-art (SOTA) detectors, including YOLOv5S, YOLOv5M, and YOLOv5L. We boosted it to 61.5% AP on the Thailand highway corpus, surpassing the current best practice (YOLOv5L) by 2.56% AP for the test-dev data set.
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Korotkii, A. A., D. A. Yakovleva, A. A. Maslennikov, and I. V. Golovko. "Modeling of information support to optimize logistics tasks in transport sector using a programmable container transformer simulator." Advanced Engineering Research 20, no. 3 (October 5, 2020): 311–16. http://dx.doi.org/10.23947/2687-1653-2020-20-3-311-316.
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Introduction. The structure of the transport logistics system for the transportation of container transformers in an urbanized environment to optimize production costs with elements of intelligent urban mobility, as well as the simulation software for modeling and testing the developed system, are described. The basic principles of the interaction between elements of the system are presented through the behavioral modeling of containers and carriers.Software is created to simulate the operation of the logistics infrastructure for transformer containers using wireless technology and the Internet of Things; and services for the rapid information exchange between participants (objects and subjects) of this process are implemented. Materials and Methods. A general method of organizing a network with a web server and a mobile client, as well as the basic principle of interaction between the server and the client, is described. The basics of developing a simulator designed to simulate all possible states of a container transformer are specified.Results. A common system architecture and a simulator are created for the software debugging and testing under the organization of a single space to monitor and optimize cargo transportation using “smart” container transformers while providing transport services to the population and legal entities in an urban environment.Discussion and Conclusions. The developed simulator as part of the information system provides speeding up the creation, debugging and testing of the software for solving logistics problems in the transport sector.
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Lesani, Mohsen, Li-yao Xia, Anders Kaseorg, Christian J. Bell, Adam Chlipala, Benjamin C. Pierce, and Steve Zdancewic. "C4: verified transactional objects." Proceedings of the ACM on Programming Languages 6, OOPSLA1 (December 8, 2022): 1–31. http://dx.doi.org/10.1145/3527324.
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Transactional objects combine the performance of classical concurrent objects with the high-level programmability of transactional memory. However, verifying the correctness of transactional objects is tricky, requiring reasoning simultaneously about classical concurrent objects, which guarantee the atomicity of individual methods—the property known as linearizability—and about software-transactional-memory libraries, which guarantee the atomicity of user-defined sequences of method calls—or serializability. We present a formal-verification framework called C4, built up from the familiar notion of linearizability and its compositional properties, that allows proof of both kinds of libraries, along with composition of theorems from both styles to prove correctness of applications or further libraries. We apply the framework in a significant case study, verifying a transactional set object built out of both classical and transactional components following the technique of transactional predication ; the proof is modular, reasoning separately about the transactional and nontransactional parts of the implementation. Central to our approach is the use of syntactic transformers on interaction trees —i.e., transactional libraries that transform client code to enforce particular synchronization disciplines. Our framework and case studieswe mentioned only one above...? are mechanized in Coq.
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Gholami, A., and H. Mehrjou. "Optimization of heat transfer at the surface of parabolic fins by genetic Algorithm." Bangladesh Journal of Scientific and Industrial Research 52, no. 4 (December 6, 2017): 325–30. http://dx.doi.org/10.3329/bjsir.v52i4.34819.
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Thermal fins are extended surfaces like longitudinal, radial, and cylindrical fins. They are used for the improvement of heat transfer between an object and fluid. Fins can be applied in many processes of objects cooling such as electrical appliances, many types of engines, transformers, chemical industry, air conditioning, heat exchangers and the industries of energy exchanges. This matter is one of the main results of paying attention to this issue. Therefore, this study examined the optimization of fin heat transfer by using a genetic algorithm and consideration of Nusselt number and hydraulic resistance as the objective function. In this paper, we investigated the optimization of the fin to maximize the heat transfer and also to minimize the hydraulic resistance. The results of this study can be effective in term of technical and economic efficiency in the industry of fin transformer. The stimulation and library method has been used to collect data. The results indicated that if the hydraulic resistance was limited to a specific value, using wavy fins will not improve the device heat.Bangladesh J. Sci. Ind. Res. 52(4), 325-330, 2017
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Lifer, M. A., and A. V. Konstantinov. "Power transformer oil recovery by antioxidant at SUEK-Khakassia." Mining informational and analytical bulletin, S64 (October 20, 2018): 145–54. http://dx.doi.org/10.25018/0236-1493-2018-12-64-145-154.
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The article discusses application of a procedure for recovery of operating processing of switch oil in 35-110 kV power transformers at objects of power supply at SUEK-Khakassia by using antioxidant Agidol. Details of process circuit, Agidol mechanisms, involved equipment maintenance, operational safety and economic efficiency of the procedure introduction in framework of implementation of basic engineering solutions are given. Entrance of oxidation inhibitor Agidol in switch oil greatly improves chemical protection of 35/110 kV power transformers from ageing and extends their operating life. This method is applicable to any TM grade oil transformers with operating life more than 10 years. The economic effect calculation proves validity of the procedure and its implementability by in-house personnel without outside contractors engaged.
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Jafarov, S. M., and A. M. Mustafayeva. "Identification of dynamic objects under uncertainty and non-stationarity using etalon transformers." Procedia Computer Science 120 (2017): 561–67. http://dx.doi.org/10.1016/j.procs.2017.11.279.
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Orosz, Tamás, and István Vajda. "Design Optimization with Geometric Programming for Core Type Large Power Transformers." Electrical, Control and Communication Engineering 6, no. 1 (October 23, 2014): 13–18. http://dx.doi.org/10.2478/ecce-2014-0012.
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Abstract A good transformer design satisfies certain functions and requirements. We can satisfy these requirements by various designs. The aim of the manufacturers is to find the most economic choice within the limitations imposed by the constraint functions, which are the combination of the design parameters resulting in the lowest cost unit. One of the earliest application of the Geometric Programming [GP] is the optimization of power transformers. The GP formalism has two main advantages. First the formalism guarantees that the obtained solution is the global minimum. Second the new solution methods can solve even large-scale GPs extremely efficiently and reliably. The design optimization program seeks a minimum capitalized cost solution by optimally setting the transformer's geometrical and electrical parameters. The transformer's capitalized cost chosen for object function, because it takes into consideration the manufacturing and the operational costs. This paper considers the optimization for three winding, three phase, core-form power transformers. This paper presents the implemented transformer cost optimization model and the optimization results.
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Malygin, Dmitry Vladimirovich, Maksim Vladimirovich Borodin, Roman Pavlovich Belikov, Yulia Lyusievna Mikhaylova, and Zumeyra Munirovna Shakurova. "The Development of A Universal Transformer Housing of the Unit Transformer Substation 6-10 / 0.4 KV." E3S Web of Conferences 288 (2021): 01097. http://dx.doi.org/10.1051/e3sconf/202128801097.
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The company group of the PJSC “ROSSETI” pays great attention to reducing occupational hazard at the facilities of the power grid complex. The analysis of the accidents in the branch of PJSC “IGDC of the Center”– “Orelenergo” revealed that transformer housings installed at the mast-type transformer substations 6-10 / 0.4 kV can’t fully provide the required safety level as they can be slightly raised even without using a special tool, and therefore one can stick his hands or some objects to the current-carrying parts of the transformer substation. According to the statistics of the damages at the mast-type transformer substations 6-10 / 0.4 kV various small animals and birds can enter the electrical installation through small slits between the housing and the transformer, which will lead to different emergency situations. To prevent the aforementioned negative consequences, a universal transformer housing was developed for a mast-type unit transformer substation (UTS) 6-10 / 0.4 kV. The offered design of the housing is universal, since it can be used for the transformers of various capacities; for its manufacture tools and materials with different characteristics can be used. At the same time, the installation of the developed housing will allow power grid companies to reduce occupational hazard, reduce the undersupply of electricity and increase the reliability of power supply to the agricultural consumers. The technical solution presented in the article can be applied for the mast-type UTS 6-10 / 0.4 kV in the post-Soviet countries.
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Ghali, Rafik, Moulay A. Akhloufi, Marwa Jmal, Wided Souidene Mseddi, and Rabah Attia. "Wildfire Segmentation Using Deep Vision Transformers." Remote Sensing 13, no. 17 (September 5, 2021): 3527. http://dx.doi.org/10.3390/rs13173527.
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In this paper, we address the problem of forest fires’ early detection and segmentation in order to predict their spread and help with fire fighting. Techniques based on Convolutional Networks are the most used and have proven to be efficient at solving such a problem. However, they remain limited in modeling the long-range relationship between objects in the image, due to the intrinsic locality of convolution operators. In order to overcome this drawback, Transformers, designed for sequence-to-sequence prediction, have emerged as alternative architectures. They have recently been used to determine the global dependencies between input and output sequences using the self-attention mechanism. In this context, we present in this work the very first study, which explores the potential of vision Transformers in the context of forest fire segmentation. Two vision-based Transformers are used, TransUNet and MedT. Thus, we design two frameworks based on the former image Transformers adapted to our complex, non-structured environment, which we evaluate using varying backbones and we optimize for forest fires’ segmentation. Extensive evaluations of both frameworks revealed a performance superior to current methods. The proposed approaches achieved a state-of-the-art performance with an F1-score of 97.7% for TransUNet architecture and 96.0% for MedT architecture. The analysis of the results showed that these models reduce fire pixels mis-classifications thanks to the extraction of both global and local features, which provide finer detection of the fire’s shape.
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SCHRIJVERS, TOM, PETER STUCKEY, and PHILIP WADLER. "Monadic constraint programming." Journal of Functional Programming 19, no. 6 (August 14, 2009): 663–97. http://dx.doi.org/10.1017/s0956796809990086.
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AbstractA constraint programming system combines two essential components: a constraint solver and a search engine. The constraint solver reasons about satisfiability of conjunctions of constraints, and the search engine controls the search for solutions by iteratively exploring a disjunctive search tree defined by the constraint program. In this paper we give a monadic definition of constraint programming in which the solver is defined as a monad threaded through the monadic search tree. We are then able to define search and search strategies as first-class objects that can themselves be built or extended by composable search transformers. Search transformers give a powerful and unifying approach to viewing search in constraint programming, and the resulting constraint programming system is first class and extremely flexible.
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Lenglet, Romain, Thierry Coupaye, and Eric Bruneton. "Composing transformations of compiled Java programs with Jabyce." Computer Science and Information Systems 1, no. 2 (2004): 83–125. http://dx.doi.org/10.2298/csis0402083l.
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This article introduces Jabyce, a software framework for the implementation and composition of transformations of compiled Java programs. Most distinguishing features of Jabyce are 1) its interaction orientation, i.e. it represents elements of transformed programs as interactions (method calls) which generally consumes less memory and CPU time than representing programs as graphs of objects; and 2) its component orientation, i.e. it allows for the design and composition of transformers as software components based on the Fractal component model. This latter point is strongly connected to infra-structural and architectural issues, and software engineering aspects such as composing, scaling, maintaining and evolving transformers. Jabyce is compared with other existing compiled Java programs transformation systems using an extension of a previous well-known categorization of program transformation systems.
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Dmitriev, S. F., A. V. Ishkov, A. O. Katasonov, V. N. Malikov, and A. M. Sagalakov. "STUDY OF CONDUCTIVE MATERIALS BY MEANS OF A MULTI-FREQUENCY MEASUREMENT SYSTEM BASED ON MICROMINIATURE EDDY CURRENT TRANSFORMERS." Dependability 17, no. 4 (November 22, 2017): 49–52. http://dx.doi.org/10.21683/1729-2646-2017-17-4-49-52.
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A measurement system has been developed that is based on an eddy current transformer and allows evaluating the applicability of the eddy current method for detecting local defects of products made of an aluminium-magnesium alloy. The paper describes the design of a microminiature eddy current transformer (ECT) with an excitation, measurement and compensation windings that uses a pyramidal core that enables localization of the magnetic field within an area about 2500 square мm. The distinctive feature of the measurement system consists in the ability to detect deep defects (up to 5 mm). The paper sets forth the primary parameters of the transformer that enable the magnetic field localization (shape, material and size of the core, number of the windings and number of loops). It also describes the process of preparation and application of several ECTs with different core and winding parameters. That allowed the ETCs generating different electromagnetic fields and reacting to the changes in that field with varied efficiency. Optimal ECT size for identifying defects in aluminium-magnesium alloys was established (pyramidal shape of the core, base 400 мm in diagonal, edge 4 mm long, 20 loops of the excitation winding, 200 loops of the measurement winding, 200±40 loops of the compensation winding). The paper describes the design of the measurement system and the measurement method that allows finding defects with the linear size of 0.25 mm situated 5 mm below the surface or more depending on the signal received from the eddy current transformer. The measurement system includes two microminiature transformers controlled by special C++ software. Voltage to the excitation winding was applied by an integrated rectangular wave generator. This setup allowed creating a magnetic field with minimal noise. The voltage of the excitation winding varied from 2 to 3V. The transformers output signal was processed in a hardware filtering system described in this paper. The distinctive feature of the measurement system is the synchronous change of the measurement signal generation frequency and filtration frequency. That enables efficient extraction of the useful signal that carries information on the defects of the tested object. The paper sets forth data that demonstrate the dependence of the amplitude part of the signal from the defects of various sizes and experimentally establishes the limit defect sizes under which such measurements are possible. The research covered objects in the form of aluminium-magnesium plates (94% Al, 3% Mg). Amplitude changes due to the linear sizes of the defects and the depth of their situation. The nature of such changes allows identifying the defects’ parameters. Depending on the size and depth of the defects, the change of the amplitude associated with the transformer passing above the defect were from 2.5V (for a defect 0.25 mm wide situated 1 mm from the surface) to 0.1V (for a defect 0.25 mm wide situated 5 mm from the surface).
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Li, Shijun, Jiayi Yang, Fumei Wu, Longfu Luo, Wendi Liao, and Jinwen Xiang. "Mathematical Model of the Integrated Filtering Reactor Windings Transformer." Journal of Physics: Conference Series 2173, no. 1 (January 1, 2022): 012011. http://dx.doi.org/10.1088/1742-6596/2173/1/012011.
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Abstract The integrated filtering reactor windings transformer is designed by a special winding arrangement design scheme. The air-core reactors of the harmonic filtering devices are integrated as the transformer windings in the transformer.so as to reduce the number of the equipments and covering area, The harmonic model of this kind of winding have been shown in this paper, and the harmonic current of each winding are deduced on the basis of the self-inductance and mutual-inductance voltage equation of multi-winding transformers. At last, this paper took a 300 KVA integrated filtering reactor winding rectifier transformer prototype as the experimental object to verify the correctness of the mathematical model.
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Katkov, M. S. "Design of structures of adaptive measuring transformers of dynamic characteristics and parameters of objects." Measurement Techniques 37, no. 9 (September 1994): 1002–10. http://dx.doi.org/10.1007/bf00980126.
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Viharev, Dmitriy, Irina Snit'ko, and A. Tihonov. "ANALYTICAL CALCULATION OF LEAKAGE INDUCTANCES BASED ON THE APPLICATION OF THE VECTOR POTENTIAL OF THE MAGNETIC FIELD." Modeling of systems and processes 14, no. 1 (March 20, 2021): 4–10. http://dx.doi.org/10.12737/2219-0767-2021-14-1-4-10.
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Methods for calculating the intrinsic and mutual leakage inductances based on the use of the vector potential of the magnetic field are considered, expressions are derived for the quantitative determination of the intrinsic and mutual inductances of the leakage fields, taking into account the geometric features of the coils, conductors and the relative position of the objects under study. The results obtained can be used to determine the parameters of the refined equivalent circuits of power transformers.
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Osintsev, Anatoly A., Aleksandra I. Naumova, and Elena I. Gracheva. "Analysis of distance protection’s operation in cases of deep saturation of current transformers." E3S Web of Conferences 288 (2021): 01095. http://dx.doi.org/10.1051/e3sconf/202128801095.
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There is usually no information about permissible error of current transformers in modes succeed by large relative short-circuit current, at which microprocessor-based protections operate stably. By this reason, it is necessary to use data, defined for analog relays. It leads to value appreciation of a project because it is often essential to reduce current transformers’ error in case of a short circuit fault. Therefore, it is necessary to define the value of current transformers’ error, permitted for impedance relays. Conclusions of fundamental and applied sciences (mathematical analysis, theoretical foundations of electrical engineering, theory of simulation), analytical methods of researching nonlinear circuits and digital signal processing were used. A simulation model was created for setting overall tests of the current trans-former (CT) system. It was a relay protection device that reflected all the important properties of studied objects and allowed an analysis of digital distance protection’s operation at high levels of short-circuit currents. The factors influ-encing over digital distance protection’s operation in case of deep saturation of CTs were revealed, and a certain algorithm for definition of the permissible CT errors was proposed. Stable operation of digital distance protection was observed in case of a fault nearby the place of current transformers’ setting in all theoretically possible combinations of electrical system’s power and length of a protected electric power transmission line. It is valid if electric load choice is carried with account for stable protection’s operation in condition of a fault in the computational point and if voltage swell in secondary wirings is infeasible.
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Bakhor, Zinovii, Andrii Yatseiko, and Roman Ferensovych. "Assessment of ferroresonance processes in schemes of 6-35 kV electrical grids on the basis of reliability analysis." Energy engineering and control systems 6, no. 2 (2020): 137–45. http://dx.doi.org/10.23939/jeecs2020.02.137.
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The object of research is the choice of the optimal technical solution to prevent the development or the long existence of ferroresonance processes in electrical distribution grids of 6-35 kV, which are operated in isolated neutral mode. A lot of factors such as the grounding mode of a grid neutral, its capacitive current of a short circuit to the ground, the type and number of voltage transformers (VT) etc. influence on the probability of occurrence and duration of ferroresonance processes. According to the results of the research, the values of capacitive currents of a short circuit to the ground at which stable ferroresonance processes occur in electrical distribution grids of 6-35 kV are determined. The values of capacitive earth fault currents of a grid are decisive for the occurrence of a stable ferroresonance, but the nature of its flow is also influenced by additional accidental factors, such as: a grid voltage, an insulation status of power lines, a load of the secondary winding of voltage transformer etc. Therefore, a model for assessment the frequency of occurrence of a stable ferroresonance process in the electrical grid based on the analysis of the reliability of physical objects in the conditions of external actions was developed. In addition, an algorithm for determining the most dangerous scheme configurations of electrical grids concerning to a VT damage by the frequency of occurrence of a stable ferroresonance process in them and the choice of optimal solutions to prevent the VT damage were proposed.
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Narakidze, Nuri D., Roman G. Oganyan, and Vasily A. Mokhov. "Analysis of heterogeneous information and diagnostics of complex technical systems based on methods of diakoptics and correlation analysis." MATEC Web of Conferences 226 (2018): 04035. http://dx.doi.org/10.1051/matecconf/201822604035.
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The article is devoted to the investigation of the applicability of the correlation analysis for the processing of heterogeneous data obtained from complex technical systems. In this article, heterogeneous data is understood to mean heterogeneous data obtained from means of monitoring the state of individual objects. The proposed approach is proposed to be used to diagnose complex technical systems using the example of digital substations. For this purpose, an imitation model for power substation based on the method of diakoptics was developed. And all components of the system, regardless of their physical functioning principles, are represented in the form of electrical sub-models. The substitution schemes based on operational amplifiers are used. The model simulates the operation of measuring current and voltage transformers, power transformer, circuit breaker and relay protection. To test the proposed approach, we also considered an amplifier circuit based on three operational amplifiers. The calculation of the circuit is described, as well as the simulation of the circuit in the MicroCap environment. The simulation was carried out with the aim of realizing parametric and structural diagnostics on the basis of correlation analysis. The results of modeling the applicability of the proposed approach for both parametric and structural diagnostics is proved operability.
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Atliha, Viktar, and Dmitrij Šešok. "Text Augmentation Using BERT for Image Captioning." Applied Sciences 10, no. 17 (August 28, 2020): 5978. http://dx.doi.org/10.3390/app10175978.
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Image captioning is an important task for improving human-computer interaction as well as for a deeper understanding of the mechanisms underlying the image description by human. In recent years, this research field has rapidly developed and a number of impressive results have been achieved. The typical models are based on a neural networks, including convolutional ones for encoding images and recurrent ones for decoding them into text. More than that, attention mechanism and transformers are actively used for boosting performance. However, even the best models have a limit in their quality with a lack of data. In order to generate a variety of descriptions of objects in different situations you need a large training set. The current commonly used datasets although rather large in terms of number of images are quite small in terms of the number of different captions per one image. We expanded the training dataset using text augmentation methods. Methods include augmentation with synonyms as a baseline and the state-of-the-art language model called Bidirectional Encoder Representations from Transformers (BERT). As a result, models that were trained on a datasets augmented show better results than that models trained on a dataset without augmentation.
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Kutin, V. M., M. V. Nikitchuk, V. M. Svitko, and O. O. Shpachuk. "AUTOMATION OF THE HEAT STATE ANALYSIS PROCESS HIGH-VOLTAGE CURRENT TRANSFORMERS." METHODS AND DEVICES OF QUALITY CONTROL, no. 2(43) (December 24, 2019): 96–110. http://dx.doi.org/10.31471/1993-9981-2019-2(43)-96-110.
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Thermographic control of electrical equipment allows you to draw preliminary conclusions about the technical condition of insulation, contact joints, windings, structural elements and cooling systems of electrical equipment of voltage classes 0.4 ÷ 750 kV. However, it should be borne in mind that the results of temperature measurement and assessment of the thermal state of electrical equipment are influenced by such factors as: environmental conditions, qualifications of personnel performing thermographic control and data interpretation, the need to improve regulatory documents for assessing the thermal state of electrical equipment and develop unified algorithms analysis of the results of thermographic examinations and gradation of the development of defects in electrical equipment.
Modern research in the field of thermographic control of electrical equipment is developing in several directions, namely: the use of automated (stationary or mobile) systems for collecting thermographic data; development of algorithms for processing thermal images that reduce the influence of extraneous noise on the values of the measured temperatures, select the image of the object being examined, select the optimal level of contrast of the thermal image to detect thermal anomalies; using statistical processing of thermal fields of thermal monitoring objects and making decisions about the thermal state of equipment using neural networks, machine learning and expert knowledge. Automation of the analysis of thermographic control data is an urgent scientific and practical task, the solution of which will improve the quality of maintenance, repairs, extension of the operating life and operational management of electrical equipment in conditions of a significant level of aging of the main production assets of electric companies and change of generations of staff.
Measuring current transformers of voltage classes 330 ÷ 750 kV are critical elements in the distribution schemes of electric power and in electric networks, and their technical condition directly affects the reliability of electric networks and power supply to consumers. The paper considers the reasons for the development of defects in current transformers of voltage classes 330 ÷ 750 kV, and also proposes relationships to take into account the influence of the air flow rate and the actual value of the emissivity of the structural element of the current transformers, as well as elements of the algorithms for analyzing data from thermal imaging surveys to reduce the influence of environmental factors and qualification level of the personnel performing the analysis, diagnostic results.
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Walczak, Krzysztof, and Wojciech Sikorski. "Non-Contact High Voltage Measurement in the Online Partial Discharge Monitoring System." Energies 14, no. 18 (September 14, 2021): 5777. http://dx.doi.org/10.3390/en14185777.
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The article presents an innovative system for non-contact high voltage (HV) measurement, which extends the measurement capabilities of a portable partial discharges (PD) monitoring system intended for diagnostics of power transformers. The proposed method and the developed measuring system are based on the use of a capacitive probe, thanks to which the high voltage measurement is safe (galvanic separation from the objects at ahigh potential). It is also flexible because the voltage ratio of this system can be configured in a wide range by changing the probe’s position. The proposed solution makes the portable PD monitoring system fully autonomous and independent of the substation systems and devices. The article presents both the concept of the non-contact HV measurement system and its practical implementation. The procedure for determining the voltage ratio and measurement uncertainty, which is at an acceptable level of 1–5% in laboratory conditions, was discussed in detail. In addition, the article discusses the digital filtering and wavelet de-noising methods implemented in the software of the monitoring system, which makes it possible to measure the voltage in the presence of strong electromagnetic disturbances occurring at the substation. Finally, the results of field tests carried out on a 250 MVA power transformer are presented, which confirmed the high accuracy of the HV measurement using a capacitive probe and the advantages of this technique.
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Krause, T. W., A. K. Krause, P. R. Underhill, and M. Kashefi. "Modeling magnetization processes in steel under stress using magnetic objects." Journal of Applied Physics 131, no. 17 (May 7, 2022): 171101. http://dx.doi.org/10.1063/5.0088329.
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The application of ferromagnetic steel products is pervasive in society, with important applications arising in electrical steel, oil and gas pipelines, transportation infrastructure, naval structures, aircraft landing gear, and automotive components. Magnetic properties of electrical steel materials play a key role in electrical motors and transformers, with a direct impact on energy efficiency. Measurement of response to magnetization has implications for non-destructive inspection methods, such as magnetic flux leakage, magnetic Barkhausen noise, and metal magnetic memory method. Examples include flaw detection, characterization of material properties, and identification of stress state in steel. An understanding of the magnetic response of steel materials can be facilitated by the use of magnetic objects (MOs). MOs are defined as regions of relatively independent magnetic behavior, typically about the size of a grain, to which fundamental magnetic energy considerations may be applied. This Tutorial outlines mechanisms by which MOs may be applied for modeling magnetic response in steel and presents examples of their application. MOs incorporate material physical properties such as microstructure, grain size, crystallographic texture, the presence of dislocations and impurity elements, and the presence of residual stress and stress load on the component. They can also accommodate a description of the evolution of magnetic domain structure under magnetizing conditions. As the MO model incorporates fundamental physics principles, it allows estimates of physical parameters that can be used to provide insights into the connections between magnetic properties and material properties, including hardness, embrittlement, and the presence of applied and residual stress. Practical applications include non-destructive characterization of the stress state of steel and an improved understanding of magnetic processes in electrical steel. Examples where such models may be applied include magnetic Barkhausen noise and magnetic memory method for the characterization of steel materials. This Tutorial summarizes recent advances in the MO model and its applications, providing the foundation for its further development. Magnetic objects have the potential to provide fundamental explanations and could form the basis for magnetic measurements and magnetization processes, including magnetic flux leakage, magnetic Barkhausen noise, and magnetic hysteresis.
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Kaliberda, I. V., S. S. Nefedov, and A. V. Pomerantsev. "Problems of Ensuring Seismic Resistance of Power Grid Facilities during Earthquakes." Occupational Safety in Industry, no. 10 (October 2020): 40–47. http://dx.doi.org/10.24000/0409-2961-2020-10-40-47.
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The electric grid system is the basis for functioning of the Unified electric power system of Russia and technologically isolated electric power systems. One of the most serious problems in the electric power industry is the aging of the fixed assets of already built and operating power grid facilities. The second problem is to clarify the seismic hazard of the territories of the Russian Federation in the direction of its growth. As a result, the number of power grid facilities fall into the zones of increased seismic hazard. In the zone of 7 points or more, approximately 30 % of the entire length of electric networks and transformer capacities are located. Information is provided about the characteristics of seismic load and how the objects respond to an earthquake. The experience of earthquakes testifies to the high vulnerability of the overhead power lines, cable power lines, substations, power transformers, relay protection equipment and automation under intense seismic loads. Information is provided about massive damage to the power grid during earthquakes in the territory of Russia, Armenia, and other countries of the world. Frequently occurring short circuits during earthquakes in electrical networks, at transformer substations, in electrical equipment elements of power grid facilities lead to fires. It is determined that power grid facilities have less seismic resistance than electric power generation facilities, than buildings and structures where electrical equipment is located. The problem of insufficiency of the current regulatory framework for ensuring seismic resistance of electric power facilities was also identified. Possible measures to prevent accident rate and increase the resistance, reliability, and seismic stability of power grid facilities in case of earthquakes are considered. The development of normative regulation will allow to take measures to ensure the seismic stability of power grid facilities in operation, and to ensure that control and supervision activities are carried out at a higher level.
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Tikhonov, Pavel V. "Energy-Saving Led Lighting System With Parallel Power Supply By Photovoltaic Modules And By Network." Volume 28, Number 6, 2020, no. 03-2020 (December 2020): 36–40. http://dx.doi.org/10.33383/2019-082.
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The current state of LED lighting systems with parallel power supply by photovoltaic modules and central power supply network is analysed. The approach to implementation of parallel operation of LED luminaire powered by two sources of power is presented. It is simple, cheap and highly reliable as compared to the existing solutions. Based on this approach, four diagrams are developed which are applicable correspondingly to lighting applications and characteristics of photovoltaic modules and power consumers. The first and the second diagrams contain minimal quantity of transformers, but a number of operational constraints shall be taken into account when using them. The third diagram contains standard transformers and implies minimal number of various constraints, which makes it an optimal solution for the low-power lighting system being designed. The fourth diagram is expensive due to utilisation of equipment with automatic maximum power point tracking (the MPPT technology); it provides maximum possible energy efficiency of the lighting systems but the advantages of the MPPT technology apply only to high-power systems. It is preferable to use such objects where lighting is mostly required during daytime as consumers of such systems (shopping malls, underground passages, storage facilities, poultry farms, etc.). A positive aspect is increase in reliability of consumer power supply since power supply of LED luminaires will be also provided by an additional source. The proposed approach leads to reduction of power consumption for LED lighting, saving of fossil energy sources and therefore to ecologisation of the environment.
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Sopov, Anatoliy I., and Aleksandr Vinogradov. "Ground Heat Accumulator for Backup Heat Supply of Energy Facilities." Elektrotekhnologii i elektrooborudovanie v APK 1, no. 42 (January 2021): 50–54. http://dx.doi.org/10.22314/2658-4859-2021-68-1-50-54.
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Many power grid facilities require heating in winter. For their heating, they usually install a system of electric heaters, connect mini gas boilers or use the thermal emissions of working electrical installations, since these objects are often located away from the sources of central heating. This leads to additional costs for the organization's own needs. It is proposed to accumulate the excess heat generated by using a ground heat accumulator, which will allow you to accumulate heat in warm periods of the year and when there is an excess of thermal energy in the system, and then use the thermal energy of the accumulator to heat the object. (Research purpose) The research purpose is in developing a ground heat accumulator capable of accumulating excess heat energy generated during the operation of high-power transformers and, if necessary, to transfer the accumulated heat to the heat supply system of energy facilities. (Materials and methods) The article considers the advantages of introducing heat storage in the heat supply systems of various facilities. Authors conducted a literary analysis of various methods of heat accumulation. (Results and discussion) The article presents the justification for the choice of a ground heat accumulator. Authors have completed the description of the proposed battery and the technology of its creation. The article describes the method of calculation of the main elements of the selected type of heat accumulator and the quantitative characteristics of the accumulator on the example of real objects. The article describes the operation of the battery in interaction with a heat pump and a horizontal ground heat exchanger. (Conclusions) The use of a heat accumulator as a backup source for energy facilities allows organizations to reduce the cost of heating premises and equipment. Additional functions that the ground heat accumulator is capable of performing are identified.
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Kandukuri, Rama Krishna, Jan Achterhold, Michael Moeller, and Joerg Stueckler. "Physical Representation Learning and Parameter Identification from Video Using Differentiable Physics." International Journal of Computer Vision 130, no. 1 (October 17, 2021): 3–16. http://dx.doi.org/10.1007/s11263-021-01493-5.
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AbstractRepresentation learning for video is increasingly gaining attention in the field of computer vision. For instance, video prediction models enable activity and scene forecasting or vision-based planning and control. In this article, we investigate the combination of differentiable physics and spatial transformers in a deep action conditional video representation network. By this combination our model learns a physically interpretable latent representation and can identify physical parameters. We propose supervised and self-supervised learning methods for our architecture. In experiments, we consider simulated scenarios with pushing, sliding and colliding objects, for which we also analyze the observability of the physical properties. We demonstrate that our network can learn to encode images and identify physical properties like mass and friction from videos and action sequences. We evaluate the accuracy of our training methods, and demonstrate the ability of our method to predict future video frames from input images and actions.
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Fesina, Mikhail, Igor Deryabin, and Gorina Larisa. "ON THE TECHNIQUE OF MISMATCHING THE RESONANT INTERACTIONS OF THE SOUND FIELDS CAUSED BY TECHNICAL OBJECTS WITH THEIR OWN ACOUSTIC MODES IN THE AIR VOLUME OF ROOMS." Akustika 32 (March 1, 2019): 24–29. http://dx.doi.org/10.36336/akustika20193224.
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Noise generating production equipment, which is located in technical rooms, first of all, is represented as power systems (pump and compressor stations, internal combustion engines, diesel-generator units, power electric transformers and electric engines, ventilation systems and air conditioning systems). As a rule, these systems operate on nominal permanent speed operation conditions ns. In their wideband sound radiation spectrum, there are found dominant discrete components which are concentrated in audio spectrum fms = 50…500 Hz, and which are characterized by corresponding sound wavelengths λms. Also, acoustic and temperature eigen fields are appeared in described volumetric air cavity of a technical room, and characterized by acoustic eigenmodes on acoustic vibration frequencies fmА and by sound wavelength λmА. Offered technical methods let eliminate the development of intensive air cavity resonance of sound radiations with proximate values of acoustic vibration frequencies fms and fmА, and sound wavelengths λms and λmА.
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Ni, Jun Fang. "Research on Manufacture Processes of Resin Dry Transformers Based on Object-Oriented Petri Net." Advanced Materials Research 299-300 (July 2011): 899–903. http://dx.doi.org/10.4028/www.scientific.net/amr.299-300.899.
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The models of resources and manufacturing processes, which aim at the production system of the resin dry transformers, are constructed by Object-oriented Petri Net (OPN) in this paper. SCB9 1000/10 400(Cu) transformer is taken as case study, the flow chart of manufacturing transformers are described at first, and then researched by static analysis, dynamic analysis and integrated application in details. The conflicts of the OPN models, which may happen in all manufacturing system of resin dry transfers, have been resolved. The whole manufacturing system are improved and optimized in the manufacture processes at last.
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Papaika, Yu A., O. H. Lysenko, Ye V. Koshelenko, and I. H. Olishevskyi. "Mathematical modeling of power supply reliability at low voltage quality." Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu, no. 2 (2021): 97–103. http://dx.doi.org/10.33271/nvngu/2021-2/097.
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Purpose. Finding dependence between reliability indexes and power quality. Working out methodology for calculation of reliability index reduction depending on poor power quality based on found dependency. Methodology. The method of harmonic analysis, the principle of superposition for instantaneous power and the methods of the theory of electric machines. The research objects are distribution processes, processes of transformation, transmitting and consumption of electrical energy in power systems of 6 and 0.4 kV with non-sinusoidal voltage in it. The subjects of the research are reliability indexes of separate power supply system units and its dependency of indexes of electromagnetic compatibility. Findings. Scientific explanation of equipment reliability index reduction depending on poor power quality in power system. Detection of the effect of non-sinusoidal voltage on the reliability of transformers and cable lines. Originality. The article analyzes the problems of electricity quality at the moment and describes the importance of solving these problems. The solutions are mainly based on the change in the level of harmonics affecting the power grids, thus improving the quality of electricity. In the work, the analysis of non-sinusoidal voltage influence on power system units reliability indexes is conducted based on typical city power supply scheme. Practical value. Finding of regularities of electromagnetic processes flaws in power system units of 6 and 0.4 kV depending on non-sinusoidal voltage level. Based on researched regularities, the process of reliability index change should be described depending on power quality. The research is conducted for such power system elements as transformers and cable lines. Based on the research, the characteristics of power system units reliability index change are built depending on the load level.
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Bezprozvannych, G. V., and I. A. Kostiukov. "A calculation model for determination of impedance of power high voltage single-core cables with polymer insulation." Electrical Engineering & Electromechanics, no. 3 (June 23, 2021): 47–51. http://dx.doi.org/10.20998/2074-272x.2021.3.08.
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Introduction. The wave parameters of power cables with polymer insulation differ significantly from the parameters of overhead lines and power transformers. As a result, there are more and more objects in electrical networks for which the occurrence of complex multi frequency transients, accompanied by dangerous overvoltages, should be expected. Purpose. To develop a computational model of the complex impedance of high-voltage single-core power cables of coaxial design required to determine the frequency dependencies of the active resistance and inductance of the conductive core and metal shield, taking into account the surface effect and proximity effect. Methodology. The method is based on solving a system of linear algebraic Kirchhoff equations (SLAE) for magnetically coupled contours. SLAE can be used to calculate conductors taking into account the skin effect and proximity effect. Practical value. The developed model is the basis for determining the characteristic impedance of high-voltage single-core power cables in a wide range of frequencies required to establish adequate criteria for evaluating the parameters of high-frequency effects critical for cross linked polyethylene insulation.
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Wu, Gang, and Yu Tang. "Design of Switch Transformer about the Push-Pull Switch Power Supply." Applied Mechanics and Materials 341-342 (July 2013): 1266–70. http://dx.doi.org/10.4028/www.scientific.net/amm.341-342.1266.
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the push-pull switch power is a kind of form in the family. It has the characteristics of good voltage output, high efficiency, the simple circuit and so on. On the design of the push-pull switch power supply, the key and difficult point is the design of switch transformer. Taking the switch transformer of a push-pull switching power supply as the research object and based on the design requirements, this paper aims to realize the calculation of the coil turns in switching transformer. Meanwhile, under the consideration of the skin effect and the proximity effect and the choices of switch transformers wires and the methods of wires winding, the design of switch transformer of the push-pull switch power supply has been completed by circuit simulation and implementation.
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Dai, Yaonan, Jiuyang Yu, Dean Zhang, Tianhao Hu, and Xiaotao Zheng. "RODFormer: High-Precision Design for Rotating Object Detection with Transformers." Sensors 22, no. 7 (March 29, 2022): 2633. http://dx.doi.org/10.3390/s22072633.
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Aiming at the problem of Transformers lack of local spatial receptive field and discontinuous boundary loss in rotating object detection, in this paper, we propose a Transformer-based high-precision rotating object detection model (RODFormer). Firstly, RODFormer uses a structured transformer architecture to collect feature information of different resolutions to improve the collection range of feature information. Secondly, a new feed-forward network (spatial-FFN) is constructed. Spatial-FFN fuses the local spatial features of 3 × 3 depthwise separable convolutions with the global channel features of multilayer perceptron (MLP) to solve the deficiencies of FFN in local spatial modeling. Finally, based on the space-FFN architecture, a detection head is built using the CIOU-smooth L1 loss function and only returns to the horizontal frame when the rotating frame is close to the horizontal, so as to alleviate the loss discontinuity of the rotating frame. Ablation experiments of RODFormer on the DOTA dataset show that the Transformer-structured module, the spatial-FFN module and the CIOU-smooth L1 loss function module are all effective in improving the detection accuracy of RODFormer. Compared with 12 rotating object detection models on the DOTA dataset, RODFormer has the highest average detection accuracy (up to 75.60%), that is, RODFormer is more competitive in rotating object detection accuracy.
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Azeem, Abdul, Majid Jamil, Shamimul Qamar, Hasmat Malik, and Rayees Ahmad Thokar. "Design of Hardware Setup Based on IEC 61850 Communication Protocol for Detection & Blocking of Harmonics in Power Transformer." Energies 14, no. 24 (December 9, 2021): 8284. http://dx.doi.org/10.3390/en14248284.
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In this paper, the authors have developed a hardware model for blocking even and odd harmonics of a power transformer. In the proposed hardware model, intelligent differential & over-current relays are used for the blocking of harmonics of a power transformer. The harmonic restraint function on the differential relay (7UT61) prevents the relay from tripping during transformer magnetizing inrush current. However, the over-current relays which are used for back up protection does not have a harmonic restraint element, and over-current relay trips due to magnetizing inrush current, causes unwanted interruptions and power failures. The establishment of harmonic blocking scheme for over-current protection in power transformers is an important finding of this research study. IEC61850 standard-Based GOOSE (Generic Object Oriented Substation Event) applications used in power transformer protection for fast detecting and clearing of faults is an interested study presented in the proposed work.
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Sousa, Antonio Roniel Marques de, Marcus Vinicius Alves Nunes, Wellington da Silva Fonseca, Ramon Cristian Fernandes Araujo, and Diorge de Souza Lima. "Magneto-Thermo-Structural Analysis of Power Transformers under Inrush and Short Circuit Conditions." Energies 14, no. 11 (June 3, 2021): 3266. http://dx.doi.org/10.3390/en14113266.
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The main equipment responsible for connection and transmission of electric power from generating centers to consumers are power transformers. This type of equipment is subject to various types of faults that can affect its components, in some cases also compromising its operation and, consequently, the electric power supply. Thus, in this paper, electromagnetic, thermal, and structural analysis of power transformers was carried out with the objective of providing the operator with information on the ideal moment for performing predictive maintenance, avoiding unplanned shutdowns. For this, computational simulations were performed using the finite element method (FEM) and, from that, the different transformer operation ways, nominal currents, inrush current, and short-circuit current were analyzed. In this perspective, analyses of the effects that thermal expansion, axial forces, and radial forces exerted were carried out, contributing to possible defects in this type of equipment. As a study object, simulations were carried out on a 50 MVA single-phase transformer. It is important to emphasize that the simulations were validated with real data of measurements and with results presented in the current literature.
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Ruban, Nikolay Yu, Mikhail V. Andreev, Ruslan A. Ufa, Aleksey A. Suvorov, and Alexandr S. Gusev. "Detailed simulation of distance protection for its testing and setting." Journal of Electrical Engineering 69, no. 3 (June 1, 2018): 189–97. http://dx.doi.org/10.2478/jee-2018-0025.
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Abstract A significant part of severe accidents (blackouts) in electric power systems (EPS) is associated with incorrect operation of relay protection and automation (RPA). One of the main reasons for the incorrect actions of the RPA devices is its rough settings, which often does not correspond to the real operating conditions for specific device. An analysis of currently used methods and tools for RPA setting up, shown that they are largely relied on the guidelines of previous decennaries. Respectively modern techniques have the same drawbacks associated with accounting the processes in specific RPA and primary transducers and its errors by approximate coefficients. It is possible to solve the indicated problem with a highly detailed analysis of the operation of key elements of RPA schemes in the specific operating conditions. The obtained results allow to estimate the processes in protected objects, processing errors in instrumental current (ICT) and voltage (IVT) transformers, as well as in RPA itself. Such possibility could be achieved by the detailed RPA mathematical modeling. The combination of an adequate EPS simulator and RPA models allows configuring parameters of the RPA settings ensuring its correct operation in real EPS. The article presents result of this research for distance protection
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Zhu, Xiaoning, Yannan Jia, Sun Jian, Lize Gu, and Zhang Pu. "ViTT: Vision Transformer Tracker." Sensors 21, no. 16 (August 20, 2021): 5608. http://dx.doi.org/10.3390/s21165608.
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This paper presents a new model for multi-object tracking (MOT) with a transformer. MOT is a spatiotemporal correlation task among interest objects and one of the crucial technologies of multi-unmanned aerial vehicles (Multi-UAV). The transformer is a self-attentional codec architecture that has been successfully used in natural language processing and is emerging in computer vision. This study proposes the Vision Transformer Tracker (ViTT), which uses a transformer encoder as the backbone and takes images directly as input. Compared with convolution networks, it can model global context at every encoder layer from the beginning, which addresses the challenges of occlusion and complex scenarios. The model simultaneously outputs object locations and corresponding appearance embeddings in a shared network through multi-task learning. Our work demonstrates the superiority and effectiveness of transformer-based networks in complex computer vision tasks and paves the way for applying the pure transformer in MOT. We evaluated the proposed model on the MOT16 dataset, achieving 65.7% MOTA, and obtained a competitive result compared with other typical multi-object trackers.
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Usachev, A. E., and A. Yu Kubarev. "Problems of Insulation Diagnostics of Power Equipment by the Method of Partial Discharges." E3S Web of Conferences 288 (2021): 01077. http://dx.doi.org/10.1051/e3sconf/202128801077.
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Target. High information value and reliability of diagnostics of isolation by partial discharges. Methods. Simulation of PD in Multisim and calculation of electrical fields of insulation defects by finite element method in the program ComSol. Results. A strong influence of the power supply on the value of voltage surge in case of emergency has been established. The method of adjustment of this influence is proposed. It was found that the oscillatory form of the PD is mainly determined not by the parameters of the insulation defect, but by the parameters of the energy object in which this defect is observed. Method for separation of aperiodic signal of PD from oscillatory component of system transient process in PD is proposed. It is shown that in operating turbogenerators and power transformers the unambiguous connection between the phase of PD occurrence and the voltage of PD occurrence is broken. Method of determination of PD occurrence place in slot part of turbogenerators is proposed. It is shown that in order to increase the reliability of comparing PD in polymer insulation of power cables of different voltage classes and geometric dimensions, when calibrating the measuring system, it is necessary to take into account the speed of propagation of the PD pulse through the cable and the capacity of the cable length unit. The concept of a corrective coefficient for calibration has been introduced and a method for determining it has been proposed. Conclusions. Taking into account the differences in PD parameters in real objects of the electric power industry, proposed in the article, from the parameters obtained in the standard laboratory model of the PD should increase the information and reliability of the PD method, as well as make it possible to conduct a comparative analysis of the results obtained under various observation conditions.
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Kalinin, I. М., О. V. Savchenko, and М. Yu Khmel. "Tests, checks and diagnostics of ship medium voltage transformers." Transactions of the Krylov State Research Centre 2, no. 400 (May 16, 2022): 103–15. http://dx.doi.org/10.24937/2542-2324-2022-2-400-103-115.
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Object and purpose of research. The study deals with the diagnostic Issues of ship MV transformers from factory acceptance tests to harbor trials. The purpose is to analyse the requirements and advanced diagnostic tools for status monitoring of ship power transformers, as well as to overview the Issues of electrodynamic withstand checks on transformers. Materials and methods. Stages (operations) are considered that ship power transformers undergo from the stage of factory acceptance tests to harbor trials. Requirements of ship transformers are analyzed. Foreign and Russian tools to check and measure power transformer parameters in industry as well as requirements for electrodynamic withstand testing are compared. Main results. It is shown that in view of high operational risks associated with accidents and failures of onboard transformers it is not enough to check transformer characteristics after transportation or storage (prior to onboard installation) for ensuring their high reliability. Functional analysis of foreign and Russian diagnostic instruments is presented, and vectors for improvement of the Russian tools are defined for the interest of shipbuilding industry. It is shown that the electric withstand tests are particularly important when new designs and technologies are used where reliable verification is impossible neither through calculations nor through modeling, while large safety margins are economically not viable. Conclusion. If some power units in the electric propulsion system (EPS) fail, extra costs would be spent on docking the vessel, dismounting of good equipment and hull structures to remove out-of-order equipment. Regulatory documenttation does not specify the scope of EPS components’ checkup after transportation or storage. Technical measures to ensure reliability of EPS elements include diagnostics of EPS elements prior to their installation on board the ship and during commissioning trials. Diagnostic tools of foreign make have more functional capabilities as compared to Russian instruments. Choice of specific devices and decisions to go for extra costs to further develop the Russian instruments should be based on feasibility studies. New regulations are required for testing rectifier transformers for electrodynamic withstand at short-circuit fault, as well as development and modernization of regional inter-industry shock test facilities.
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Xu, Dapeng, Yu Mao, Xiaohui Yang, Chunxu Qin, Haikun Shang, Jun Zhao, Jianying Zhang, and Zhiwei Li. "Analysis of winding temperature field under dynamic variable load of oil-immersed transformer." Thermal Science 25, no. 4 Part B (2021): 3009–19. http://dx.doi.org/10.2298/tsci2104009x.
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The research on the temperature field of the transformer winding under dynamic variable load is of great significance for ensuring the safe operation of power systems. This paper takes an SSP-360000/500 transformer as the research object, establishes a 2-D simulation model, and uses the finite volume method to analyze the high voltage winding and low voltage winding temperature distribution of the transformer under dynamic variable load. The simulation calculation results have been fully verified by the experimental data to make the successful prediction of the overall temperature and hot spot temperature position of forced oil circulation transformers with a guided structure. The results show that the most significant temperature raise occurs at the secondary end of the winding. In the case of dynamic variable load. The temperature raise of the winding becomes larger as the load increases, but before the rated load is in the stable temperature rise range, it can run safely for a long time. However, during overload operation, the average temperature raise of the high voltage winding may exceed its limit, the insulation material is damaged.
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Gujarathi, Mr Pratik. "Automatic Pneumatic Sheet Metal Feeding and Cutting Machine." International Journal for Research in Applied Science and Engineering Technology 9, no. 11 (November 30, 2021): 150–65. http://dx.doi.org/10.22214/ijraset.2021.38734.
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Abstract: Today in the rapid competition of the industries to get the best quality of the product in the minimum required time is the main aim of industries. To get the best quality and maximum production most advanced machines are used. But there are no facts that use only the advanced machines, to maintain their performance is real requirement of the industries, also to give proper facilities to the workers with good environmental condition and to reduce their efforts is one of the objects to achieve the best quality and high production. Sheet metal is simply a metal formed into thin and flat pieces. It is one of the fundamental forms used in metal working and can be cut and bent into a variety of different shapes. Countless everyday objects are constructed of the material. Thicknesses can vary significantly, although extremely thin thicknesses are considered foil or leaf, and pieces thicker than 6 mm (0.25 in) are considered plate. Sheet metal also has applications in car bodies, airplane wings, medical tables, roofs for buildings (Architectural) and many other things. Sheet metal of iron and other materials with high magnetic permeability, also known as laminated steel cores, has applications in transformers and electric machines. There are three primary procedures in Layout. They are Parallel, Radial, and Triangulation. The major aim to our experiment is to study about pneumatic control system, study about double acting cylinder, study about the advantage of pneumatic hand operated valve and study about high speed blade. We are using scissors for simple sheet metal cutting. It is a manual method so that sheet metals are to be wasted sometimes because of mistakes happened such as wrong dimensions etc., and also even a simple cutting may take long time. We are using a pneumatic system for sheet metal cutting in an easy way. It is operated by a pneumatic hand lever of two ways control valve. Control valve is operated by a compressor. Keywords: Pneumatic, Automation, Sheet Metal, Pneumatic, Valve, Cutting Machine
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Landowski, Bogdan, Daniel Perczyński, and Łukasz Muślewski. "Application of Markov Model for Determination of Average Lifetime of a Transformer Distribution System." Journal of KONBiN 50, no. 3 (October 1, 2020): 151–73. http://dx.doi.org/10.2478/jok-2020-0055.
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AbstractThe study presents an analysis of the operation process of elements of a system for electrical energy transformation in natural conditions of their usage. The research object is a system of HV and MV distribution transformer operation. The method of construction and an example of the Markov operation process have been presented for the analyzed technical objects. The model of the operation process was built on the basis of analysis of spatial states and events involved in operation of the analyzed technical objects. An average lifetime of the analyzed technical system was determined for assumptions accepted for a stochastic process which is a mathematical model of the distribution transformer operation process.
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Yahya, А. A., and V. M. Levin. "Bayesian classifier is the tool of increasing the efficiency of defects recognition in power transformers." Power engineering: research, equipment, technology 21, no. 6 (April 21, 2020): 11–18. http://dx.doi.org/10.30724/1998-9903-2019-21-6-11-18.
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The article considers the method of forming a statistical Bayesian classifier in relation to the problems of operational diagnostics and rapid evaluation of the technical condition of transformer equipment. It is proposed to use the classifier as a regular means to improve the reliability of defect recognition in power oil-filled transformers based on the analysis of dissolved gases in oil. A stochastic approach to the formation of the classifier in a conditions linearly realized dichotomy of technical status classes is developed. As a distinguishing feature, a nonlinear function of the primary parameters of state is used. This simultaneously achieves both a reduction in the dimension of the feature space and an improvement in the characteristics of the random distribution. The proposed approach allows to form a decisive rule that minimizes the total error of decision-making regardless of the impact on the object of random operational factors. The results of the study of stochastic properties of the distributions of the distinguishing feature for each of the selected classes of states are obtained. The algorithm to perform statistical calculations and procedures for recognizing the current state of the transformer using the generated decision rule is designed. The results of the study illustrate the possibility of practical application of the developed approach in the real exploitation of power transformers.