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Journal articles on the topic 'Electric motors, Induction. Harmonic functions'
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1
Andrade, Darizon A. de, Marcos A. A. de Freitas, Luciano M. Neto, Hélder de Paula, and José L. Domingos. "Effects of magnetic saturation on induction machines driven by static converters." Sba: Controle & Automação Sociedade Brasileira de Automatica 15, no. 2 (June 2004): 181–89. http://dx.doi.org/10.1590/s0103-17592004000200007.
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The effects of magnetic saturation on the operation of induction motors driven by static converters are analyzed. A mathematical model based on magnetic harmonic functions is used to account for saturation. Distortions on the air gap flux due to non-linear magnetic characteristics lead to appearance of space harmonics in the resultant flux density distribution. This causes specific distortions in stator and rotor time quantities, which are different from those due to static converter. Operation with six pulse and sinusoidal PWM converters under saturated conditions is considered. Comparisons of experimental and simulated results are presented and found to be in very good agreement.
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Batista, Edson A., Moacyr A. G. de Brito, João C. Siqueira, Jeandro C. Dias, Raphael C. Gomez, Maurilio F. R. Catharino, and Matheus B. Gomes. "A Multifunctional Smart Meter Using ANN-PSO Flux Estimation and Harmonic Active Compensation with Fuzzy Voltage Regulation." Sensors 21, no. 12 (June 17, 2021): 4154. http://dx.doi.org/10.3390/s21124154.
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This paper aims to present the analysis and development of a complete electronic smart meter that is able to perform four-quadrant measurements, act as a three-phase shunt active power filter (APF), and control three-phase induction motors by stator flux estimation. A transmission control protocol together with Internet protocol (TCP/IP) communication protocol for the remote access of measurement data is embedded into the application to securely transmit reliable information. An artificial neural network trained with particle swarm optimization is used for stator flux estimation, and a fuzzy logic controller is adopted to regulate the power converter DC bus voltage. The present work gathers knowledge from multidisciplinary fields, and all applied techniques have not been proposed altogether before. All control functions are embedded into a field-programmable gate array (FPGA) device, using VHSIC Hardware Description Language (VHDL), to enhance efficiency taking advantage of parallelism and high speed. An FPGA-in-the-loop cosimulation technique was first applied to prove the control functions’ functionality, and, later, experimental evaluations are conducted to finally prove equipment operation and reliability.
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Muñoz Tabora, Jonathan, Maria Emília de Lima Tostes, Edson Ortiz de Matos, Thiago Mota Soares, and Ubiratan Holanda Bezerra. "Voltage Harmonic Impacts on Electric Motors: A Comparison between IE2, IE3 and IE4 Induction Motor Classes." Energies 13, no. 13 (June 30, 2020): 3333. http://dx.doi.org/10.3390/en13133333.
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Global energy systems are undergoing a transition process towards renewable energy and energy efficiency practices. Induction motors play an important role in this energy transformation process since they are widely used as industrial loads, representing more than 53% of global energy consumption. With more countries adopting minimum energy performance standards through more efficient induction motors, comparisons between these new technologies in the presence of electrical disturbances must be systematically evaluated before adopting a substitution policy in the industry. To this end, this work presents a comparative analysis of the impact of harmonic voltages on the performance and temperature rise of electric motors classes IE2, IE3 and IE4 in the same operational conditions in view of future substitutions. The results show that under ideal operating conditions the IE4 class permanent magnet motor has better performance in terms of consumption and temperature, however presenting non-linear characteristics. In the presence of voltage harmonics, this scenario changes completely according to the harmonic content. Finally, aiming to analyze the harmonics influence in the motor temperature rise a statistical analysis by means of Spearman correlation matrices is presented.
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Pugachev, Alexander, and Galina Fedyaeva. "Definition of the Transfer Function Parameters of Asynchronous Motor as an Object of Temperature Control." Applied Mechanics and Materials 698 (December 2014): 124–30. http://dx.doi.org/10.4028/www.scientific.net/amm.698.124.
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The analysis and systematization of research methods of thermal state of induction motors including traction ones is done. It is shown that for each type of motor it is necessary to develop its own mathematical model of thermal processes, and its verification should be carried out only on the basis of experimental investigations. The structure and operating principles of the complex developed physical model of the traction electric drive with induction motors is represented. The motors have a cooling system with variable-speed electric fan and subsystem of measurement and recording of monitored parameters. The method and the results of experimental study of the processes of heating and cooling of the induction motor are illustrated. Transfer functions and approximation curves of transients are proposed, their parameters are defined.
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Kindl, Vladimir, Radek Cermak, Zelmira Ferkova, and Bohumil Skala. "Review of Time and Space Harmonics in Multi-Phase Induction Machine." Energies 13, no. 2 (January 19, 2020): 496. http://dx.doi.org/10.3390/en13020496.
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Modern multiphase electric machines take advantage of additional degrees of freedom for various purposes, including harmonic current injection to increase torque per ampere. This new approach introduces a non-sinusoidal air gap flux density distribution causing additional technical problems and so the conventional assumptions need to be revised. The paper presents a methodology for synthesis of air gap magnetic field generated by a symmetrically distributed multiphase windings including the rotor field reaction due to the machine’s load. The proposed method is suitable either for single-layer or double layer windings and can be adopted either for full-pitched or chorded winding including slots effects. The article analyses the air gap flux density harmonic content and formulates conclusions important to multiphase induction motors. It also discusses effects of time harmonic currents and illustrates the principle of changing number of pole-pairs typical for harmonic currents being injected to increase torque.
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Balleteros Csmcho, Manuel Ivan, Francy Julieth Cadena Villalba, and Adolfo Andres Jaramillo Matta. "TÉCNICAS DE PROCESAMIENTO DE SEÑALES UTILIZADAS PARA EL ANÁLISIS DE LA DISTORSIÓN ARMÓNICA GENERADA POR VARIADORES DE FRECUENCIA EN MOTORES DE INDUCCIÓN." Redes de Ingeniería 6, no. 1 (September 5, 2015): 72. http://dx.doi.org/10.14483/udistrital.jour.redes.2015.1.a05.
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Se presenta una detallada revisión del estado del arte de las técnicas de procesamiento de señales utilizadas para el análisis de la distorsión armónica generada por variadores de frecuencia en motores de inducción con rotor jaula de ardilla, referenciando algunas de las investigaciones más relevantes relacionadas con este tema. Finalmente, son identificadas oportunidades de investigación que a la fecha no han sido tratadas por la comunidad científica en este campo del conocimiento.Signal Processing Techniques Used for Analyzing Harmonic Distortion Generated by Variable Frequency Drive in Induction Motors Abstract This article presents a detailed review of the state of the art of signal processing techniques used for the analysis of harmonic distortion generated by variable frequency induction motors with squirrel cage rotor is presented, referencing some of the most relevant research related with this issue. Finally, are identified research opportunities that to date have not been addressed by the scientific community in this field of knowledge.Keywords: electric motor-driven system, state of the art, harmonic distortion, signal processing techniques.
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Ludowicz, Wojciech, Dawid Danielczyk, and Rafał M. Wojciechowski. "Project of a universal inverter used to control and supply both AC and DC electric motors." ITM Web of Conferences 28 (2019): 01018. http://dx.doi.org/10.1051/itmconf/20192801018.
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The paper presents the new approach for motor driver constructions and control systems. Authors of the work proposed the device that can control both AC and DC electric motors without any additional hardware modification. In order to meet this goal the universal motor driver has been constructed and some improvements in output waveform modulation system have been introduced. In the paper the three different method of a motor control have been discussed briefly and a hardware setup has been presented. Tests have been carried out for three types of electric motors, i.e. a magnetoelectric DC motor, single-phase and three-phase induction motor. The obtained results in form of output waveforms of current and voltage have been analyzed in terms of harmonic distortion using a popular Fast Fourier Transform FFT and discussed in the paper.
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Denisova, E. V., K. N. Marenich, and E. S. Dubinka. "A Dual-speed Induction Motor as a Source of Electrical Hazard in Operating Conditions of Coal Mine Process Support Areas." Mining Industry Journal (Gornay Promishlennost), no. 4/2021 (August 25, 2021): 145–52. http://dx.doi.org/10.30686/1609-9192-2021-4-145-152.
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Hazardous states of the mine zonal electrical network are caused by the reversed energy flows of induction motors of the energy-consuming equipment in the run-down mode after the power supply is switched off. The electromotive force (EMF) induced in the powered-off stator windings of the dual-speed motors due to the transformer effect also pose a danger of electric shock. The paper presents a methodology and the results of studying the formation of induced EMFs in the powered-off stator windings of dual-speed induction motors, including the run-down mode and the functions that impact on the electromagnetic parameters. Analysis of the impact degree of these induced EMFs on the electrical safety parameters as part of the mine zonal electrical network is presented.
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Dariescu, Marina-Aura, and Ciprian Dariescu. "Mathieu functions for fermions generated in magnetar’s corona." Modern Physics Letters A 32, no. 32 (October 12, 2017): 1750174. http://dx.doi.org/10.1142/s0217732317501747.
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This work deals with the behavior of fermions in a configuration supposed to exist in magnetar’s corona. For a static magnetic induction parallel to a time-harmonic electric field, the solution to the U(1)-gauge invariant Dirac equation is expressed in terms of Laguerre polynomials and Mathieu’s functions of complex parameter. Using the Fourier series valid before the branching point, we are computing the conserved current density components.
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Deaconu, Sorin Ioan, Marcel Topor, Gabriel Nicolae Popa, and Feifei Bu. "Hybrid Electric Vehicle with Matrix Converter and Direct Torque Control in Powertrains Asynchronous Motor Drives." MATEC Web of Conferences 292 (2019): 01066. http://dx.doi.org/10.1051/matecconf/201929201066.
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Electric transportation has made rapid developments and significant steps toward the full electrical powertrain systems. With the increased use of electric vehicles energy conversion systems several technologies have been developed and reached a high degree of performance. Since electric vehicles and hybrid are the more cost competitive technology available today, the evolution toward a more reliable powertrain combining different electric powertrain systems is needed. Induction machine and permanent magnet generators/motors integrated powertrains have some significant advantages over other types of systems such as no need of excitation, low volume and weight, high precision, and no use of a complex gearbox for torque/speed conversion. A electric vehicle powertrain for EV propulsion with a induction motor and a matrix converter is proposed in this paper. The induction motor is controlled using the direct torque flux algorithm. The traditional power conversion stages consist of a rectifier followed by an inverter and bulky DC link capacitor. It involves 2 stages of power conversion and, subsequently, the efficiency of the overall EV is reduced because of power quality issues mainly based on total harmonic distortion. The proposed solution incorporates a matrix converter is mainly utilized to control the induction electric motor for propulsion. The matrix converter is a simple and compact direct AC-AC converter. The proposed EV with matrix converter is modeled using PSIM.
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DARIESCU, MARINA-AURA, and CIPRIAN DARIESCU. "ON THE MATHIEU EQUATION DESCRIBING ULTRA-RELATIVISTIC FERMIONS EVOLVING IN A TIME-HARMONIC ELECTRIC FIELD PARALLEL TO A STATIC MAGNETIC INDUCTION." Modern Physics Letters A 28, no. 35 (October 30, 2013): 1350157. http://dx.doi.org/10.1142/s0217732313501575.
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The present work is studying the behavior of relativistic fermions in parallel electric and magnetic fields, oriented along Oz. As expected, in the particular case of static field intensities, the temporal part of the wave function is expressed in terms of the parabolic cylinder functions. When the static electric field is replaced by a time-harmonic one, the ultra-relativistic particles are described by a Mathieu-type equation, of purely imaginary parameter. Below the first branching point, which imposes a maximum value for the electric intensity, one may use a series expansion of the Mathieu's functions to derive the corresponding wave functions and the conserved current density components. Finally, we obtain a nontrivial quantization law of the longitudinal momentum, pz.
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Darmawansyah, Darmawansyah, M. Khairul Amri Rosa, and Ika Novia Anggraini. "Sistem Proteksi Motor Induksi 3 Fasa Terhadap Bermacam Gangguan Menggunakan Mikrokontroller." JURNAL AMPLIFIER : JURNAL ILMIAH BIDANG TEKNIK ELEKTRO DAN KOMPUTER 10, no. 1 (May 30, 2020): 9–17. http://dx.doi.org/10.33369/jamplifier.v10i1.15168.
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ABSTRACTIn the current era of globalization, various human jobs depend on electrical equipment such as three-phase induction motors. Three-phase induction motors are very important to use according to their roles and functions. The occurrence of voltage variations in the electric power system is due to the magnitude of the voltages between the three phases which are not the same so that there are differences in the angle of the R, S and T phases, which causes an uneven load overload in the electrical distribution system. Among the disturbances that can occur are overvoltage, under voltage, unbalance voltage between phases, overload, and overheating. Based on these problems, a three-phase induction motor protection system was designed, the system uses current, voltage, temperature sensors, which functions to measure the value when a disturbance occurs, a magnetic contactor as a breaker and a liaison when the disturbance is given in accordance with the set point value given to the microcontroller. The results of the research for unbalanced voltage of V1 112 V, V2 114 V, V3 108 V, overvoltage of V1 228 V, V2 207 V, V3 264 V, over current of A1 104 A, A2 107 A, A3 0.77 A , the overload on the resistance source is 333 ?, 250 ?, 200 ?, 167 ?, and the overheating is 40.75 ºC at 6.5 minutes with tripping conditions in each test. The final results of this study indicate that the protection system which is designed is better used for three-phase induction motors.Keywords: unbalaced, disturbances, protection systems, sensors, magnetic contactor, microcontroller.
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Karatoprak, Erinc, and Serhat Seker. "An Improved Empirical Mode Decomposition Method Using Variable Window Median Filter for Early Fault Detection in Electric Motors." Mathematical Problems in Engineering 2019 (February 19, 2019): 1–9. http://dx.doi.org/10.1155/2019/8015295.
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This paper proposes an improved Empirical Mode Decomposition (EMD) method by using variable window size median filters during the Intrinsic Mode Functions (IMFs) generation. Compared to the traditional EMD, the improved EMD, namely, Median EMD (MEMD), helps to reduce mode-mixing providing an improvement in terms of separating the fundamental frequencies per IMF. The MEMD method applies the EMD to the signal and then applies a variable window size median filter to the resulting IMFs. A narrow window is used for high frequency components where a broader window is used for the lower frequency components. The filtered IMFs are then summed again and another round of EMD is applied to yield the improved MEMD IMFs. A test setup for accelerated aging of bearings in induction motors is used for the comparison of the traditional and the improved EMD methods with the goal of finding potential bearing defects in an induction motor. The potential defect at the early stage is compared with the faulty state and is used to extract the characteristics of the bearing damage that develops gradually. Comparing the EMD and MEMD, it is seen that MEMD is an improvement to EMD in terms of mode-mixing problem. The MEMD method demonstrated to have better performance compared to the traditional EMD for the extraction of the fault features from the healthy operational state of the motor.
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Ewert, Pawel, Teresa Orlowska-Kowalska, and Kamila Jankowska. "Effectiveness Analysis of PMSM Motor Rolling Bearing Fault Detectors Based on Vibration Analysis and Shallow Neural Networks." Energies 14, no. 3 (January 30, 2021): 712. http://dx.doi.org/10.3390/en14030712.
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Permanent magnet synchronous motors (PMSMs) are becoming more popular, both in industrial applications and in electric and hybrid vehicle drives. Unfortunately, like the others, these are not reliable drives. As in the drive systems with induction motors, the rolling bearings can often fail. This paper focuses on the possibility of detecting this type of mechanical damage by analysing mechanical vibrations supported by shallow neural networks (NNs). For the extraction of diagnostic symptoms, the Fast Fourier Transform (FFT) and the Hilbert transform (HT) were used to obtain the envelope signal, which was subjected to the FFT analysis. Three types of neural networks were tested to automate the detection process: multilayer perceptron (MLP), neural network with radial base function (RBF), and Kohonen map (self-organizing map, SOM). The input signals of these networks were the amplitudes of harmonic components characteristic of damage to bearing elements, obtained as a result of FFT or HT analysis of the vibration acceleration signal. The effectiveness of the analysed NN structures was compared from the point of view of the influence of the network architecture and various parameters of the learning process on the detection effectiveness.
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Nerubatskyi, V. P., O. A. Plakhtii, D. V. Tugay, and D. A. Hordiienko. "Method for optimization of switching frequency in frequency converters." Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu, no. 1 (2021): 103–10. http://dx.doi.org/10.33271/nvngu/2021-1/103.
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Purpose. To present a methodology for determining the optimal switching frequency in frequency converters and autonomous voltage inverters, the load of which is an asynchronous electric motor. The methodology is based on determining the dependences of static and dynamic power losses in the power switches of the inverter on the switching frequency and the dependence of power losses in the windings of an induction motor on the higher harmonics of currents, which also depend on the switching frequency. Methodology. Polynomial approximation of the energy characteristics of power transistors. General provisions of the theory of electrical circuits. The determination of additional power losses in the windings of an induction motor from higher harmonics is based on analytical calculation and simulation in the Matlab/Simulink software environment and a specialized program from the manufacturer of power switches Mitsubishi MelcoSim5.1. Findings. A method for optimizing the frequency of pulse-width modulation in frequency converters, the load of which is an asynchronous motor, is presented according to the criterion of the minimum total power losses in the power transistors of the inverter and the resistance of the motor windings. The proposed calculation technique allows determining the dependence of static and dynamic losses in power IGBT-transistors with a sufficiently high accuracy while being in the MelcoSim software environment. To calculate the losses in the motor, it is shown that the switching frequency of the power switches affects the harmonic distortion factor and the average value of the phase current of the induction motor. Provided that only the first harmonic of the current performs the useful action in an asynchronous motor, the dependence of additional power losses on the switching frequency is given. Originality. A method for optimizing the frequency of pulse-width modulation by the criterion of minimum additional power losses in the resistance of the motor windings from higher harmonics of the current and static and dynamic losses in the power transistors of the inverter is presented. An analytical dependence of additional power losses in the active resistance of the windings of induction motors as a function of the harmonic distortion factor of the phase current of an autonomous voltage inverter is presented. Practical value. The presented technique makes it possible to determine the optimal modulation frequency in frequency converters with asynchronous motors and to ensure the minimum total power losses and the maximum value of efficiency in the autonomous voltage inverter asynchronous motor system.
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Solomin, Vladimir A., Anastasia A. Bichilova, Larisa L. Zamshina, and Nadezhda A. Trybitsina. "Adjustable Squirrel-Cage Linear Induction Motor for Magnetic Levitation Transport." Transportation systems and technology 3, no. 4 (December 15, 2017): 127–49. http://dx.doi.org/10.17816/transsyst201734127-149.
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The article deals with linear induction motor (LIM) with a squirrel-cage winding of the secondary element (SE), which functions as the armature of the machine. Linear location of squirrel-cage winding of the secondary element of LIM allowed suggesting a number of options for the regulation of the winding resistance of SE. Objective. Development and research of LIM with adjustable winding resistance of the secondary element for magnetic levitation transport, and the study of the properties of adjustable LIM. At the modern level of development of the electrical engineering, asynchronous electric drive and magnetic levitation transport, the primary method of changing the frequency rotation of motor and speed of linear motion of high-speed transport vehicles is frequency control. Frequency control allows changing the frequency of rotation of the machine and linear speed of LIM smoothly and in broad diapason. The high cost of static electronic converters of high power limits the large-scale application of frequency control. The increase of the current frequency also leads to lower torque and traction. Results. According to the authors, the application of the adjustable linear induction motors with variable resistances of short-circuited windings of the secondary elements will allow to expand the range of control of LIM, intended for high-speed magnetic levitation transport with the realisation of large traction, including the start (starting the vehicle) by means of current displacement in the groove of the secondary element of the LIM. Conclusion. The linear induction motors of this type, as well as the calculation of the magnetic field in the groove of the secondary element, and evaluation of the influence of the current displacement on the starting and controlling features of the machine are considered.
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Beriber, D., A. Talha, and M. Boucherit. "Stabilization of multi DC bus link voltages of multilevel NPC VSI. Application to double stator induction motors." Archives of Control Sciences 22, no. 1 (January 1, 2012): 107–20. http://dx.doi.org/10.2478/v10170-011-0015-1.
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Stabilization of multi DC bus link voltages of multilevel NPC VSI. Application to double stator induction motors Voltage source multilevel inverters have become very attractive for power industries in power electronics applications during last years. The main purposes of studying multilevel inverters are the generation of output voltage signals with low harmonic distortion and reduction of switching frequency. An important issue of the multilevel inverter is the capacitor voltage-balancing problem. The unbalance of different DC voltage sources of multilevel neutral point clamped (NPC) voltage source inverter (VSI) constitutes the major limitation for the use of this new power converter. In this paper, we present study on the stability problem of the input DC voltages of the three-level Neutral Point Clamping (NPC) voltage source inverter (VSI). This inverter is useful for application in high voltage and high power area. In the first part, we remind the model of double stator induction motors (DSIM). Then, we develop control models of this inverter using the connection functions of the semi-conductors. We propose a Pulse Width Modulation (PWM) strategy to control this converter. The inverter is fed by constant input DC voltages. In the last part, we study the stability problem of the input DC voltages of the inverter. A cascade constituted by two three-level PWM rectifiers - two three-level NPC VSI - DSIM is discussed. The results obtained show that the input DC voltages of the inverters are not stable. To solve this problem, we propose to use a half clamping bridge. This solution is very promising in order to stabilize the input DC voltages of this converters.
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Martinez-Roman, Javier, Ruben Puche-Panadero, Angel Sapena-Bano, Manuel Pineda-Sanchez, Juan Perez-Cruz, and Martin Riera-Guasp. "Winding Tensor Approach for the Analytical Computation of the Inductance Matrix in Eccentric Induction Machines." Sensors 20, no. 11 (May 28, 2020): 3058. http://dx.doi.org/10.3390/s20113058.
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Induction machines (IMs) are critical components of many industrial processes, what justifies the use of condition-based maintenance (CBM) systems for detecting their faults at an early stage, in order to avoid costly breakdowns of production lines. The development of CBM systems for IMs relies on the use of fast models that can accurately simulate the machine in faulty conditions. In particular, IM models must be able to reproduce the characteristic harmonics that the IM faults impress in the spatial waves of the air gap magneto-motive force (MMF), due to the complex interactions between spatial and time harmonics. A common type of fault is the eccentricity of the rotor core, which provokes an unbalanced magnetic pull, and can lead to destructive rotor-stator rub. Models developed using the finite element method (FEM) can achieve the required accuracy, but their high computational costs hinder their use in online CBM systems. Analytical models are much faster, but they need an inductance matrix that takes into account the asymmetries generated by the eccentricity fault. Building the inductance matrix for eccentric IMs using traditional techniques, such as the winding function approach (WFA), is a highly complex task, because these functions depend on the combined effect of the winding layout and of the air gap asymmetry. In this paper, a novel method for the fast and simple computation of the inductance matrix for eccentric IMs is presented, which decouples the influence of the air gap asymmetry and of the winding configuration using two independent tensors. It is based on the construction of a primitive inductance tensor, which formulates the eccentricity fault using single conductors as the simplest reference frame; and a winding tensor that converts it into the inductance matrix of a particular machine, taking into account the configuration of the windings. The proposed approach applies routine procedures from tensor algebra for performing such transformation in a simple way. It is theoretically explained and experimentally validated with a commercial induction motor with a mixed eccentricity fault.
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Ładziński, Radosław. "Dynamic Systems with a Finite Degrees of Freedom Number." Archives of Control Sciences 24, no. 2 (June 1, 2014): 207–34. http://dx.doi.org/10.2478/acsc-2014-0013.
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Abstract Taking as a starting point the law of conservation of the total energy of the system, and introducing two basic state functions - the Lagrangian and the Rayleigh function, the general form of the equation of motion for any dynamic system with a finite number of degrees of freedom is derived. The theory is illustrated by considering the rotating - type electromechanical energy converter with six degrees of freedom being the model of all essentially important types of DC and AC machines, including rotating power amplifiers, induction - and synchronous type motors - all of them discussed from both, the steady-state and the transient point of view. In the next part of the paper there is described a simple electric circuit with its model characterized by the holonomic constraints of the velocity-type. Finally, there is presented the kinematics and dynamics of the interesting mechanical system - the gyroscope placed on the rotating Earth.
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Dubovik, Mikhail E., and Vyacheslav A. Solovyev. "Dynamic Model of a Dual Power Machine Controlled from the Rotor Side." Electrotechnical Systems and Complexes, no. 2(43) (June 28, 2019): 60–64. http://dx.doi.org/10.18503/2311-8318-2019-2(43)-60-64.
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In the high power mode, the power of which exceeds 100 kW, as a rule, when energy is used in asynchronous motors it requires voltage up to 1000 V. This is due to a decrease in the weight and dimensions of the motor. But when developing a frequency-controlled electric drive, it is necessary to use a high-voltage frequency converter (FC), which leads to a significant increase in the cost of electrical wiring. A compromise solution can be found by using a dual power supply machine (MIS), a frequency control channel that needs to be transferred to the rotor circuit [1]. The use of TIR will significantly reduce capital costs and expand control functions over the drive. The article presents a mathematical description of a dual power machine. The main feature of this description is the choice of coordinate system. On the basis of it and taking into account its characteristics, a dynamic model of the machine has been built. The research group investigated the dynamic characteristics of the machine when applying a control signal from the rotor with a variable frequency. Control signals are presented in the form of ideal harmonic functions. In the further study, the constructed model will make it possible to investigate the launch of the machine in various modes. The dependence of the amplitude of the rotor voltage on its frequency is obtained. This dependence shows the possible range of variation of the voltage amplitude on the rotor while maintaining the synchronous MOS mode at a given speed. Simulation is made in electrical degrees. All angular velocities (rad / s) are expressed in frequencies (Hz). The behavior of the machine in a static mode was investigated when the load torque changes. A simulation model built in the Matlab environment is given.
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Wang, Gong Li, and Aria Abubakar. "Rapid simulation of borehole electromagnetic response in axially symmetric and transversely isotropic formations." GEOPHYSICS 83, no. 4 (July 1, 2018): E245—E257. http://dx.doi.org/10.1190/geo2017-0095.1.
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Downhole well-logging data acquired by modern electromagnetic (EM) tools enables determining not only conductivity but also conductivity anisotropy of reservoirs. The most popular anisotropic model for EM data interpretation is a horizontally layered model with transverse isotropic conductivity in each layer. Such a model ignores the conductivity change caused by the mud-filtrate invasion that often occurs in a permeable layer. The invasion effect can be so strong that the conductivity derived using the 1D model can be substantially affected. We have developed an efficient forward-modeling approach that includes the invasion in the formation model so that the invasion effect can be properly accounted for in data interpretation and inversion. The approach uses a Fourier series expansion for the electric field in the azimuthal direction to take advantage of the invariance of conductivity in this direction. Each harmonic in the expansion is expressed in terms of numerical eigenmodes in the radial direction and exponential functions in the vertical direction. Physically, the latter describes a set of plane waves propagating upward or downward in the vertical direction. This property allows us to use reflection and transmission matrices to couple EM fields from layer to layer, making it highly efficient to simulate EM logging response because the two matrices are computed only once for all logging points. The approach is best suited for a multilayer and transversely isotropic formation in which each layer can have an arbitrary number of radial discontinuities. Numerical experiments demonstrate that the new approach can accurately model the response of induction and propagation tools in various formations. A speedup of two orders of magnitude is obtained in a multilayer case compared with a previous 2D method using a different hybridization strategy.
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"E-Type Asymmetric Multilevel Inverter Based Transformer less Traction Drive." VOLUME-8 ISSUE-10, AUGUST 2019, REGULAR ISSUE 8, no. 10 (August 10, 2019): 2579–89. http://dx.doi.org/10.35940/ijitee.j9293.0881019.
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To overcome the limitations of conventional multilevel inverter such as of more no. of power semiconductor switches, large no. of capacitors, more switching loss etc. , a new topology of Envelope type (E-type) MLI is used. This E-type Module has some preferable features like reduced no. of components and low switching frequency. This E-type asymmetric converter uses four unequal DC sources and ten switches to generate 13 level of output voltage. SHE modulation technique is used to achieve high quality output voltage with low harmonic content. This E-type converter configuration will be used in transformer less traction drive. Nowadays Induction motors are used as electric drives for most of the electric railways. A transformer less connection is used for feeding Induction motor. This converter-inverter configuration will convert single phase AC voltage to DC and again this DC voltage will be converted into three phase AC. The output of the E-type Multi level inverter will be used to drive the Induction motors.
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Widarsono, Kukuh. "Design Phase Delay Control for Soft Starting 3 Phase Induction Motor." JAREE (Journal on Advanced Research in Electrical Engineering) 4, no. 1 (April 26, 2020). http://dx.doi.org/10.12962/j25796216.v4.i1.100.
Full textAbstract:
Induction Motor is one type of electric machine that is widely used both in household consumers and industrial players. However, induction motors have drawbacks, namely starting currents that can reach 5-7 times the nominal current, of course this can lead to reduced life time of other electrical equipment and the possibility of shutdown or trip is very large. This research proposes a new modeling to create a soft starting system to reduce the 3 phase induction motor start current. This system was built with the help of a Phase Delay Control power electronics circuit with the main component, Triac, which functions to regulate the input voltage of a 3 phase induction motor and a contactor whose function is to move the 3 phase induction motor power supply from the soft starting system to the PLN source directly if, The input voltage is the same as the nominal voltage. The output of these processes is the Triac ignition angle, so during the starting process, the induction motor will receive an input voltage in stages from the smallest to reach its nominal voltage. Thus the results of testing the soft starting system that is designed to have a maximum current value at the start of 2.45 A or 77.58% lower than the start current using the DOL method with a value of 10.93 A at no-load conditions and 7.41 A or 34.19% lower than the motor starting current with the DOL method with a value of 11.31 A when the motor is loaded.