Dissertations / Theses: 'Non minimum phase plant'

1

Zhao, Shen. "Practical Solutions to the Non-minimum Phase and Vibration Problems under the Disturbance Rejection Paradigm." Cleveland State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=csu1334670962.

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Šalda, Zbyněk. "Ukázky regulací s prediktivním řízením." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-232182.

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This thesis deals with model predictive control principally Based Predictive Control (MPC). The first part describes the principle of predictive control, cost function, the choice of a constraints in regulation and the choice of weights. In the next section is an analysis system: a system with non-minimal phase (control water turbine), oscillating systems (trolley frame control) and system with a time-delay . In all of these systems is performed classical feedback control using PID control and concurrently regulation with the MPC. MPC is selected as the solution fy Mathworks Model Predictive Control Toolbox and Simulink. The results are then analyzed using the criteria of quality control.

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Apasa, Ryad Faddel. "Non-minimum phase parallel-coupled microstrip filters." Thesis, Cranfield University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302738.

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Dudiki, Venkatesh. "Feed-Forward Compensation of Non-Minimum Phase Systems." Wright State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=wright1545163596477852.

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Hashemi-Zahan, Saeid. "Inversion of non-minimum phase systems in signal processing." Thesis, University of Southampton, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266944.

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Boudria, Yacine. "Tracking control for non-minimum phase system and brain computer interface." Thesis, University of Rhode Island, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3716673.

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For generations, humans dreamed about the ability to communicate and interact with machines through thought alone or to create devices that can peer into a person’s mind and thoughts. Researchers have developed new technologies to create brain computer interfaces (BCIs), communication systems that do not depend on the brain’s normal output pathways of peripheral nerves and muscles. The objective of the first part of this thesis is to develop a new BCI based on electroencephalography (EEG) to move a computer cursor over a short training period in real time. The work motivations of this part are to increase: speed and accuracy, as in BCI settings, subject has a few seconds to make a selection with a relatively high accuracy.

Recently, improvements have been developed to make EEG more accurate by increasing the spatial resolution. One such improvement is the application of the surface Laplacian to the EEG, the second spatial derivative. Tripolar concentric ring electrodes (TCREs) automatically perform the Laplacian on the surface potentials and provide better spatial selectivity and signal-to-noise ratio than conventional EEG that is recorded with conventional disc electrodes. Another important feature using TCRE is the capability to record the EEG and the TCRE EEG (tEEG) signals concurrently from the same location on the scalp for the same electrical activity coming from the brain. In this part we also demonstrate that tEEG signals can enable users to control a computer cursor rapidly in different directions with significantly higher accuracy during their first session of training for 1D and 2D cursor control.

Output tracking control of non-minimum phase systems is a highly challenging problem encountered in many practical engineering applications. Classical inversion techniques provide exact output tracking but lead to internal instability, whereas modern inversion methods provide stable asymptotic tracking but produce large transient errors. Both methods provide an approximation of feedback control, which leads to non robust systems, very sensitive to noise, considerable tracking errors and a significant singularity problem. Aiming at the problem of system inversion to the true system, the objective of the second part of this thesis is to develop a new method based on true inversion for minimum phase system and approximate inversion for non-minimum phase systems. The proposed algorithm is automatic and has minimal computational complexities which make it suitable for real-time control.

The process to develop the proposed algorithm is partitioned into (1) minimum phase feedforward inverse filter, and (2) non-minimum phase inversion. In a minimum phase inversion, we consider the design of a feedforward controller to invert the response of a feedback loop that has stable zero locations. The complete control system consists of a feedforward controller cascaded with a closed-loop system. The outputs of the resulting inverse filter are delayed versions of the corresponding reference input signals, and delays are given by the vector relative degree of the closed-loop.

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Hu, Ai-Ping. "Nonlinear non-minimum phase output tracking via output redefinition and learning control." Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/16644.

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Wang, Pengfei. "Causal tracking control of a non-minimum phase HIL transmission test system." Thesis, University of Bath, 2009. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.518103.

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The automotive industry has long relied on testing powertrain components in real vehicles, which causes the development process to be slow and expensive. Therefore, hardware in the loop (HIL) testing techniques are increasingly being adopted to develop electronic control units (ECU) for engine and other components of a vehicle. In this thesis, HIL testing system is developed to provide a laboratory testing environment for continuously variable transmissions (CVTs). Two induction motors were utilized to emulate a real engine and vehicle. The engine and vehicle models, running in real-time, provide reference torque and speed signals for input and output dynamometers, respectively. To design torque and speed tracking controllers, linear models of the motor and drive systems were firstly identified from the test results. Feedforward controllers were then designed according to the inverse dynamics of the identified models. Because of the existence of unstable zeros in the model, design effort was focused on the stability and causality of the inverse process. Digital preview filters were formulated to approximate the stable inverse of unstable zeros as part of the feedforward controller. Normally, future information of input trajectory is required when implementing the digital preview filters, which makes the feedforward controller non-causal. Since the engine and vehicle model require current information to calculate the next output and no future value can be provided in advance, the application of non-causal digital controllers was limited. A novel method is proposed here to apply non-causal digital controllers causally. Robustness of the controllers is also considered when the two motors are coupled and the gear ratio between them was changed. The proposed coupled control method was tested and verified experimentally by using a manual gearbox before recommending its use for a CVT testing. A multifrequency test signal as well as simulation results of a whole vehicle model were used as torque and speed demand signals in the experiments. A HIL testing case was also presented. Frequency and time domain results showed the effectiveness of the method under both testing procedures to fully compensate for the dynamics of both actuators.

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9

Lan, Chenyang. "Synthesis of controllers for non-minimum phase and unstable systems using non-sequential MIMO quantitative feedback theory." Thesis, Texas A&M University, 2003. http://hdl.handle.net/1969.1/2245.

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Considered in this thesis is multi-input multi-output (MIMO) systems with non-minimum phase (NMP) zeros and unstable poles where some of the unstable poles are located to the right of the NMP zeros. In the single-input single-output (SISO) case such systems pose serious difficulties in controller synthesis for performance and stability. In spite of the added degrees of freedom the MIMO case also poses difficulties as has been shown in the stabilization of the X-29 aircraft. When using the MIMO QFT technique the synthesis starts by considering a set of equivalent SISO plants derived from the plant transfer function matrix that are used to develop a controller. In effect the design problem is reduced to several MISO designs with the diagonal entries of as the equivalent SISO plants. Developed is a transformation scheme that can be used to condition the resulting equivalent SISO plants so that the difficult problem of NMP zeros lying to the left of unstable poles is avoided. Examples illustrate the use of the proposed transformation.

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Liu, Gang. "Sliding mode output tracking control of nonlinear non-minimum phase and time-delay systems." Thesis, University of Sheffield, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443901.

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11

Benosman, Mouhacine. "Commande des bras manipulateurs souples et extensions aux systèmes à non minimum de phase." Nantes, 2002. http://www.theses.fr/2002NANT2016.

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Nous nous sommes intéressés dans cette thèse à la commande des bras manipulateurs souples. Certaines des méthodes proposées ont été généralisées au cas des systèmes à non minimum de phase. Nous avons proposé les résultats suivants : 1- Une méthode d'inversion stable des systèmes linéaires SISO à non minimum de phase, par planification de trajectoires de sorties. Cette approche a été appliquée au robot à un axe souple, et a été validée par des tests expérimentaux. 2- Une approche de commande du bras manipulateur à un axe souple, basée sur la paramétrisation des opérateurs différentiels linéaires. La méthode a été validée par des tests expérimentaux. 3- Suivi de sortie par une méthode d'inversion stable pour une classe de systèmes non linéaires à non minimum de phase, basée sur une formulation par problème au deux bouts. Cette approche a été appliquée en simulation au PVTOL (Planar Vertical Take Off and Landinh aircraft), ainsi qu'aux bras manipulateurs multi-axes souples plans. Des tests expérimentaux ont été réalisés sur un robot à deux axes souples. .
This thesis concerns the control of the flexible manipulators. We have generalised some of the proposed control schemes to the case of non minimum phase systems. .

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Ontanon-Ruiz, Javier. "Non-minimum phase effects in geared robot transmissions and their resolution using a differential drive." Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337523.

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13

Prigent, Michel. "Contribution à l'étude de la conversion de fréquence dans les circuits non-linéaires application à la C.A.O. d'oscillateurs à bruit de phase minimum /." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37609048j.

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Prigent, Michel. "Contribution à l'étude de la conversion de fréquence dans les circuits non-linéaires : Application à la C.A.O. d'oscillateurs à bruit de phase minimum." Limoges, 1987. http://www.theses.fr/1987LIMO0033.

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Par l'etude quantitative de l'interaction entre bruit et signal fort, on realise un logiciel permettant de simuler les spectres de bruit des oscillateurs a t. E. C. Par calcul de la conversion de frequence auteur de la porteuse des generateurs de bruit. Application a la c. A. O. Des circuits non lineaires hyperfrequences

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15

Gatehouse, Hazel A. W. "Ecology of the naturalisation and geographic distribution of the non-indigenous seed plant species of New Zealand." Diss., Lincoln University, 2008. http://hdl.handle.net/10182/1009.

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The naturalisation and subsequent spread of non-indigenous plant species (NIPS) is a major problem for most regions of the world. Managing plant invasions requires greater understanding of factors that determine initial naturalisation and distribution of wild NIPS. By the year 2000, 2252 NIPS were recorded as wild (1773 fully naturalised and 479 casual) in New Zealand. From published literature and electronic herbaria records, I recorded year of discovery of wild populations, and regional distribution of these wild NIPS. I also recorded species related attributes hypothesised to affect naturalisation and/or distribution, including global trade, human activities, native range and biological data; and regional attributes hypothesised to affect distribution, including human population densities, land use/cover, and environmental data. I used interval-censored time-to-event analyses to estimate year of naturalisation from discovery records, then analysed the importance of historical, human activity, biogeographical and biological attributes in determining patterns of naturalisation. Typically, NIPS that naturalised earlier were herbaceous, utilitarian species that were also accidentally introduced and/or distributed, with a wide native range that included Eurasia, naturalised elsewhere, with a native congener in New Zealand. In the year 2000, 28% of wild NIPS occupied only one region, 18% occupied two regions, decreasing incrementally to 2.5 % for nine regions, but with 13.5% occupying all ten regions. I used generalised linear models (GLMs) with binomial distribution to determine predictors of whether a wild NIPS occupied ten regions or not, and GLMs with Poisson distribution for wild NIPS occupying 0 – 9 regions. As expected, the dominant effect was that species discovered earlier occupied more regions. Utilitarian wild NIPS that were also accidentally introduced and/or distributed, and wild NIPS with a native congener tended to be more widely distributed, but results for other attributes varied between datasets. Although numbers of wild NIPS recorded in regions of New Zealand were sometimes similar, composition of wild NIPS was often very different. I used nonmetric multidimensional scaling (NMDS) to determine dissimilarity in composition between regions. Then, after reducing correlation between predictor variables using principal components analyses (PCAs), I tested the importance of regional variables in determining the regional composition of wild NIPS using metaMDS. The density of human populations best explained the dissimilarity in composition, but temperature gradients and water availability gradients were also important. In the year 2000 more than 1100 (60%) of the 1773 fully naturalised NIPS in mainland New Zealand had each been recorded in Northland/Auckland and Canterbury, and at the other end of the scale, Southland and Westland each had fewer than 500 (30%). I used GLMs to analyse the importance of people and environment in determining the numbers of wild NIPS in each region. Because I conducted multiple tests on the same dataset I used sequential Bonferroni procedures to adjust the critical P-value. Only human population density was important in explaining the numbers of NIPS in the regions. Overall, humans were the dominant drivers in determining the patterns of naturalisation and spread, although environment helps determine the composition of NIPS in regions. Incorporating human associated factors into studies of wild NIPS helps improve the understanding of the stages in the naturalisation and spread process.

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16

Daasch, Andreas [Verfasser], Ferdinand [Akademischer Betreuer] Svaricek, Ferdinand [Gutachter] Svaricek, and Klaus [Gutachter] Röbenack. "Determination of Non-Minimum Phase Systems by the Structural Approach / Andreas Daasch ; Gutachter: Ferdinand Svaricek, Klaus Röbenack ; Akademischer Betreuer: Ferdinand Svaricek ; Universität der Bundeswehr München, Fakultät für Luft- und Raumfahrttechnik." Neubiberg : Universitätsbibliothek der Universität der Bundeswehr München, 2019. http://d-nb.info/1221223674/34.

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Daasch, Andreas [Verfasser], Ferdinand [Akademischer Betreuer] Svaricek, Ferdinand Gutachter] Svaricek, and Klaus [Gutachter] [Röbenack. "Determination of Non-Minimum Phase Systems by the Structural Approach / Andreas Daasch ; Gutachter: Ferdinand Svaricek, Klaus Röbenack ; Akademischer Betreuer: Ferdinand Svaricek ; Universität der Bundeswehr München, Fakultät für Luft- und Raumfahrttechnik." Neubiberg : Universitätsbibliothek der Universität der Bundeswehr München, 2019. http://d-nb.info/1221223674/34.

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18

Dabo, Marcelin. "Commande prédictive généralisée non linéaire à temps continu des systèmes complexes." Phd thesis, Université de Rouen, 2010. http://tel.archives-ouvertes.fr/tel-00497319.

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Nous abordons, dans cette thèse, la poursuite asymptotique de trajectoire basée sur la commande prédictive généralisée non linéaire à temps continu (NCGPC). L'application de cette technique de commande requiert la vérification d'assomptions précises. La NCGPC est caractérisée par deux paramètres : le degré relatif et l'horizon de prédiction, respectivement, intrinsèque et extrinsèque au système. Sa loi de commande résulte de la minimisation d'un critère quadratique basée sur l'erreur de prédiction (jusqu'à un ordre égal au degré relatif) entre la(es) sortie(s) choisie(s) et le(es) signal(aux) de référence correspondant(s). Elle linéarise le système non linéaire en boucle fermée dans un nouvel espace de coordonnées et lui garantit la stabilité (degré relatif inférieur ou égal à quatre) de facto. Au-delà de quatre, il y a instabilité. Pour résoudre ce problème, Chen et al. ont introduit un troisième paramètre, qui est l'ordre des dérivées successives de la commande par rapport au temps, choisi de sorte que sa différence avec le degré relatif soit inférieure à quatre. Nous proposons dans ce travail, deux approches qui vérifient les mêmes assomptions mentionnées ci-dessus et dont les points communs sont la modification du critère avec le maintien à zéro de l'ordre des dérivées successives de la commande et la garantie de la stabilité pour le système linéaire bouclé résultant. La première approche consiste au rajout d'un terme linéaire en commande au critère, tandis que la deuxième consiste au rajout d'une matrice de correction "intelligente" à la matrice de prédiction du critère. Quelques propriétés de la NCGPC sont données pour des systèmes SISO de degré relatif un ou deux.

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Taylor, Jonathan. "Robust Bode Methods for Feedback Controller Design of Uncertain Systems." Research Showcase @ CMU, 2014. http://repository.cmu.edu/dissertations/447.

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In this work, we introduce several novel approaches to feedback controller design, known collectively as the “Robust Bode” methods, which adapt classical control principles to a modern robust control (H∞) framework. These methods, based on specially modified Bode diagrams extend familiar frequency-domain controller design techniques to linear and nonlinear, single–input/single– output (SISO) and multi–input/multi–output (MIMO) systems with parametric and/or unstructured uncertainties. In particular, we introduce the Contoured Robust Controller Bode (CRCBode) plots which show contours (level-sets) of a robust metric on the Bode magnitude and phase plots of the controller. An iterative loop shaping design procedure is then employed in an attempt to eliminate all intersections of the controller frequency response with certain forbidden regions indicating that a robust stability and performance criteria is satisfied. For SISO systems a robust stability and performance criterion is derived using Nyquist arguments leading to the robust metric used in the construction of the CRCBode plots. For open-loop unstable systems and for non-minimum phase systems the Youla parametrization of all internally stabilizing controllers is used to develop an alternative Robust Bode method (QBode). The Youla parametrization requires the introduction of state-space methods for coprime factorization, and these methods lead naturally to an elegant connection between linear-quadratic Gaussian (LQG) optimal control theory and Robust Bode loop-shaping controller design. Finally, the Robust Bode approach is extended to MIMO systems. Utilizing a matrix norm based robustness metric on the MIMO CRCBode plots allows cross-coupling between all input/output channels to be immediately assessed and accounted for during the design process, making sequential MIMO loop-shaping controller design feasible.

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Waqar, Mohsin. "Robust nonlinear observer for a non-collocated flexible motion system." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22696.

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21

Campestrini, Lucíola. "Contribuições para métodos de controle baseados em dados obtidos em apenas um experimento." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/26865.

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Este trabalho apresenta algumas contribuições para métodos de controle baseados em dados obtidos em apenas um experimento, a fim de torná-los mais atrativos quanto à aplicação em processos industriais. A partir de dados obtidos em experimentos no processo, os métodos baseados em dados estimam os parâmetros de um controlador de estrutura fixa por meio da minimização do erro entre a saída do sistema real em malha fechada e uma saída desejada, dada por um modelo de referência. O método Virtual Reference Feedback Tuning - VRFT é o método mais expressivo na literatura que estima os parâmetros do controlador usando apenas uma batelada de dados, mas o mesmo apresenta alguns inconvenientes em sua formulação que limitam a sua aplicação. Neste trabalho, o método VRFT é modificado de forma que se obtém um método VRFT flexível, o qual minimiza um critério flexível, pelo qual são estimados tanto os parâmetros do controlador quanto os parâmetros do numerador do modelo de referência; assim, caso a planta que se deseja controlar seja de fase não-mínima, o critério é capaz de estimar esses zeros e os mesmos devem ser incluídos no modelo de referência que será utilizado no projeto do controlador. Além disso, em sistemas com ruído, o método VRFT necessita de uma variável instrumental para que a estimativa dos parâmetros do controlador seja não-polarizada. Para eliminar a necessidade de usar variáveis instrumentais, um novo método de controle baseado em dados é proposto, o qual é descrito sob a ótica de identificação. Este método pode ser visto como a identificação de um sistema, no qual a função de transferência do processo é reparametrizada em função do controlador ideal e do modelo de referência. Além disso, estende-se a teoria de projeto de experimento com solução baseada em restrições LMI para o caso da identificação do controlador ótimo. Todas essas contribuições são ilustradas através de simulações.
This work presents some contributions to data-based control methods where data is obtained in only one experiment, in order to make them more attractive to industrial process applications. Using data from experiments on the process, data-based methods estimate the parameters of fixed structure controller, through the minimization of the error between the closed loop response of the system and the desired response, given by a reference model. The Virtual Reference Feedback Tuning - VRFT method is the most expressive method in the literature that estimates the controller parameters using only one batch of data, but this method presents some inconveniences in its formulation which limit its application. In this work, the VRFT method is modified in order to obtain a flexible VRFT method, which minimizes a flexible criterion, and then obtains the controller parameters together with the parameters related to the reference model numerator; thus, if the plant which we want to control is non-minimum phase, then the criterion is able to estimate these zeros and they need to be included in the reference model that will be used in the control design. Besides, when dealing with noisy systems, the VRFT method needs an instrumental variable so the controller parameters estimate is unbiased. In order to eliminate this necessity, a new data-based control is proposed in this work, which is formulated using identification theory. This method can be seen as the identification of a system, where the process transfer function is reparameterized as a function of the ideal controller and the reference model. Besides, we extend the experimental design theory where the problem is solved using LMI constraints to the case of the optimal controller identification method. All these contributions are illustrated through simulations.

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Prasitmeeboon, Pitcha Prasitmeeboon. "Robustification and Optimization in Repetitive Control For Minimum Phase and Non-Minimum Phase Systems." Thesis, 2017. https://doi.org/10.7916/D8FT8SD8.

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Repetitive control (RC) is a control method that specifically aims to converge to zero tracking error of a control systems that execute a periodic command or have periodic disturbances of known period. It uses the error of one period back to adjust the command in the present period. In theory, RC can completely eliminate periodic disturbance effects. RC has applications in many fields such as high-precision manufacturing in robotics, computer disk drives, and active vibration isolation in spacecraft. The first topic treated in this dissertation develops several simple RC design methods that are somewhat analogous to PID controller design in classical control. From the early days of digital control, emulation methods were developed based on a Forward Rule, a Backward Rule, Tustin’s Formula, a modification using prewarping, and a pole-zero mapping method. These allowed one to convert a candidate controller design to discrete time in a simple way. We investigate to what extent they can be used to simplify RC design. A particular design is developed from modification of the pole-zero mapping rules, which is simple and sheds light on the robustness of repetitive control designs. RC convergence requires less than 90 degree model phase error at all frequencies up to Nyquist. A zero-phase cutoff filter is normally used to robustify to high frequency model error when this limit is exceeded. The result is stabilization at the expense of failure to cancel errors above the cutoff. The second topic investigates a series of methods to use data to make real time updates of the frequency response model, allowing one to increase or eliminate the frequency cutoff. These include the use of a moving window employing a recursive discrete Fourier transform (DFT), and use of a real time projection algorithm from adaptive control for each frequency. The results can be used directly to make repetitive control corrections that cancel each error frequency, or they can be used to update a repetitive control FIR compensator. The aim is to reduce the final error level by using real time frequency response model updates to successively increase the cutoff frequency, each time creating the improved model needed to produce convergence zero error up to the higher cutoff. Non-minimum phase systems present a difficult design challenge to the sister field of Iterative Learning Control. The third topic investigates to what extent the same challenges appear in RC. One challenge is that the intrinsic non-minimum phase zero mapped from continuous time is close to the pole of repetitive controller at +1 creating behavior similar to pole-zero cancellation. The near pole-zero cancellation causes slow learning at DC and low frequencies. The Min-Max cost function over the learning rate is presented. The Min-Max can be reformulated as a Quadratically Constrained Linear Programming problem. This approach is shown to be an RC design approach that addresses the main challenge of non-minimum phase systems to have a reasonable learning rate at DC. Although it was illustrated that using the Min-Max objective improves learning at DC and low frequencies compared to other designs, the method requires model accuracy at high frequencies. In the real world, models usually have error at high frequencies. The fourth topic addresses how one can merge the quadratic penalty to the Min-Max cost function to increase robustness at high frequencies. The topic also considers limiting the Min-Max optimization to some frequencies interval and applying an FIR zero-phase low-pass filter to cutoff the learning for frequencies above that interval.

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Gavini, Sree Likhita. "Control of Non-minimum Phase Power Converters." 2012. http://hdl.handle.net/1805/3361.

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Indiana University-Purdue University Indianapolis (IUPUI)
The inner structural characteristics of non-minimum phase DC-DC converters pose a severe limitation in direct regulation of voltage when addressed from a control perspective. This constraint is reflected by the presence of right half plane zeros or the unstable zero dynamics of the output voltage of these converters. The existing controllers make use of one-to-one correspondence between the voltage and current equilibriums of the non-minimum phase converters and exploit the property that when the average output of these converters is the inductor current, the system dynamics are stable and hence they indirectly regulate the voltage. As a result, the system performance is susceptible to circuit parameter and load variation and require additional controllers, which in turn increase the system complexity. In this thesis, a novel approach to this problem is proposed for second order non-minimum phase converters such as Boost and Buck-Boost Converter. Different solutions have been suggested to the problem based on whether the converter is modeled as a linear system or as a nonlinear system. For the converter modeled as a linear system, the non-minimum phase part of the system is decoupled and its transfer function is converted to minimum phase using a parallel compensator. Then the control action is achieved by using a simple proportional gain controller. This method accelerates the transient response of the converter, reduces the initial undershoot in the response, and considerably reduces the oscillations in the transient response. Simulation results demonstrate the effectiveness of the proposed approach. When the converter is modeled as a bilinear system, it preserves the stabilizing nonlinearities of the system. Hence, a more effective control approach is adopted by using Passivity properties. In this approach, the non-minimum phase converter system is viewed from an energy-based perspective and the property of passivity is used to achieve stable zero dynamics of the output voltage. A system is passive if its rate of energy storage is less than the supply rate i.e. the system dissipates more energy than stores. As a result, the energy storage function of the system is less than the supply rate function. Non-minimum phase systems are not passive, and passivation of non-minimum phase power converters is an attractive solution to the posed problem. Stability of non-minimum phase systems can also be investigated by defining the passivity indices. This research approaches the problem by characterizing the degree of passivity i.e. the amount of damping in the system, from passivity indices. Thus, the problem is viewed from a system level rather than from a circuit level description. This method uses feed-forward passivation to compensate for the shortage of passivity in the non-minimum phase converter and makes use of a parallel interconnection to the open-loop system to attain exponentially stable zero dynamics of the output voltage. Detailed analytical analysis regarding the control structure and passivation process is performed on a buck-boost converter. Simulation and experimental results carried out on the test bed validate the effectiveness of the proposed method.

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24

"Output regulation for non-minimum phase nonlinear systems." 2007. http://library.cuhk.edu.hk/record=b5893488.

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Zhong, Renxin.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2007.
Includes bibliographical references (leaves 107-114).
Abstracts in English and Chinese.
Abstract --- p.iv
Chapter 1 --- Introduction --- p.1
Chapter 1.1 --- Non-Minimum Phase Nonlinear Systems --- p.1
Chapter 1.2 --- Robust Output Regulation Problem --- p.4
Chapter 1.3 --- Global Robust Output Regulation for Non-Minimum Phase Nonlinear Systems in Lower Triangular Form --- p.6
Chapter 1.4 --- Rotational/Translational Actuator System --- p.8
Chapter 1.5 --- Organization and Contributions --- p.8
Chapter 2 --- Global Robust Output Regulation for Non-Minimum Phase Non-linear Systems in Lower Triangular Form --- p.10
Chapter 2.1 --- Introduction --- p.10
Chapter 2.2 --- Assumptions and Preliminaries --- p.12
Chapter 2.3 --- Solvability Conditions --- p.17
Chapter 2.4 --- Numerical Examples --- p.19
Chapter 2.5 --- Concluding Remarks --- p.46
Chapter 3 --- Global Robust Output Regulation for A Class of Non-Minimum Phase Nonlinear Systems by Output Feedback Control --- p.47
Chapter 3.1 --- Introduction --- p.48
Chapter 3.2 --- Assumptions and Preliminaries --- p.49
Chapter 3.3 --- Reduced order observer design --- p.56
Chapter 3.4 --- Stabilization of x system --- p.59
Chapter 3.5 --- "Interconnection of the n,z,ζ,x subsystems and small gain condition" --- p.63
Chapter 3.6 --- Numerical example --- p.67
Chapter 3.7 --- Conclusion --- p.76
Chapter 4 --- Robust output regulation for the nonlinear benchmark problem via output feedback --- p.77
Chapter 4.1 --- Introduction --- p.78
Chapter 4.2 --- Disturbance rejection problem of the RTAC system by output feedback control --- p.79
Chapter 4.3 --- Robust Disturbance rejection problem of the RTAC system by output feedback --- p.88
Chapter 4.4 --- Conclusion --- p.98
Chapter 5 --- Conclusion --- p.103
List of Figures --- p.105
Bibliography --- p.107
Biography --- p.115

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25

Lee, Far-Yi, and 李芳怡. "Direct Adaptive Control of Non-minimum Phase Process Systems." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/92321889962452393390.

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碩士
逢甲大學
化學工程學系
87
In this dissertation, we develop an adaptive control scheme for non-minimum phase system. The proposed scheme incorporates an adaptive single neural controller（SNC）and a minimum phase predictor（MPP）. The function of the designed MPP is to simulate the difference between the process transfer function with and without the minimum phase factor. Consequently, a corrective signal is added to the measured output to predict what the output would have been if there were no non-minimum phase factor present. With the aid of MPP, the SNC is able to learn to control the non-minimum phase system adaptively by adapting its parameters. In the same framework, we consider the direct adaptive control of non-minimum phase system in the presence of input hand constraints and delays. In addition, we further extend the proposed scheme to nonlinear non-minimum phase systems, where a statically-equivalent MPP is designed for nonlinear systems. Illustrative examples were provided for the demonstration of the proposed scheme. Extensive comparisons of the proposed adaptive control strategy with some of existing schemes were performed. Due to the simple structure, efficient algorithm and good performance, we believe the proposed adaptive control scheme is a promising approach to the direct control of non-minimum phase process systems.

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26

Lee, Yen-Ju, and 李硯儒. "Unknown Input Estimation for LTI Non-Minimum Phase Systems." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/fb492u.

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碩士
國立中山大學
電機工程學系研究所
106
In real-world applications, the output performance of a dynamical system is often affected by external disturbances. One way to reduce, or even eliminate, the influence of the disturbance is to construct a observer to estimate the disturbance signal, so that a control action based on the disturbance estimate can be taken to against its effect. In general, an input disturbance observer can be constructed based on the inverse of the plant dynamics, but this method is not applicable when the plant has non-minimum phase zeros. In this case, inverting the non-minimum phase zeros would result in unstable dynamics, and hence an unstable observer, which is unacceptable. In this thesis we propose a novel approach for designing input disturbance observers for LTI non-minimum phase systems. The core concept of the method that we proposed lies in finding a bounded solution of an unstable differential equation. Based on this concept, a mathematical algorithm is developed to "inverse" the effect of non-minimum phase zeros without incurring unbounded signals. The technique is then applied in building input disturbance observers for continuous-time and discrete-time LTI non-minimum phase systems. The effect of our approach is verified by several numerical examples and compared with the existing methodologies in the literature.

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Hsu, Wei-Ching, and 徐瑋青. "Neural Network Enhanced Predictive Control Designs for Non-minimum Phase Processes." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/73818486299764254313.

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碩士
國立雲林科技大學
工業化學與災害防治研究所
91
Model predictive control (MPC) is one of the most frequently used process control strategies.　The principle of MPC is to have a process model, which is able to predict the process response, in the MPC controller.　The manipulated variable is tuned in order to minimize the deviation between the set point and the predicted response for a period of time in the feature.　The goal of process control can therefore be achieved by regulating the manipulated variable. We use neural networks, which have strong ability of identification.Then we collocate with optimal operation to establish a neural network predictive control (NNPC) structure. On the other hand, in order to reduce the error between the predictive model and true system immediately and increase the accuracy of prediction, we use the dynamic backpropagation (DBP) learning algorithm to adjust the weights of neural network during the on-line procedure. The whole control structure becomes a adaptive neural network predictive control (ANNPC). We also use two kinds of control method to control Non-minimum phase systems. Through the simulation, we get the performance and tenacity of two control methods.

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28

Kuo-YangLiao and 廖國洋. "New PI Optimal Linear Quadratic State-Estimate Trackers for Non-Square Non-Minimum Phase Systems." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/sre6r6.

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DIAO, LILI. "Adaptive Output Feedback Stabilization of Nonlinear Systems." Thesis, 2009. http://hdl.handle.net/1974/5370.

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Output feedback control design techniques are required in practice due to the limited number of sensors/measurements available for feedback. This thesis focuses on output feedback controller design techniques for nonlinear systems subject to different system restrictions. The problem of controlling the heart dynamics in a real time manner is formulated as an adaptive learning output-tracking problem. For a class of nonlinear dynamic systems with unknown nonlinearities and non-affine control input , a Lyapunov-based technique is used to develop a control law. An adaptive learning algorithm is exploited that guarantees the stability of the closed-loop system and convergence of the output tracking error to an adjustable neighborhood of the origin. In addition, good approximation of the unknown nonlinearities is also achieved by incorporating a per- sistent exciting signal in the parameter update law. The effectiveness of the proposed method is demonstrated by an application to a cardiac conduction system modelled by two coupled driven oscillators. An output feedback design technique is developed to achieve semi-global practical stabilization for a class of non-minimum phase nonlinear systems, subject to param- eter uncertainties. This work provides a constructive controller design method for an auxiliary system, whose existence is crucial, but is only assumed in (Isidori, 2000). The control design technique is used to regulate the benchmark van de Vusse reactor. Simulation results demonstrate satisfactory controller performance. The output feedback control design for a class of non-minimum phase nonlinear systems with unknown nonlinearities is studied. The proposed approach is able to combine the two previous design methods and provide a stabilizing output feedback control law. The performance of the proposed method is demonstrated by simulation results.
Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2009-12-22 15:47:05.884

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30

Min-ChingChung and 鍾旻京. "A Generalized Linear Quadratic Digital Tracker for the Non-Square Non-Minimum/Minimum Phase Discrete-Time Systems with the Known/Unknown Disturbance and Noise." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/ak8aqg.

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碩士
國立成功大學
電機工程學系
103
In this thesis, a generalized linear quadratic digital tracker (LQDT) for the more general discrete-time system, which has a direct-feedthrough term and the known system disturbances, has been presented, and it will be applied in some control problems to achieve design goals. In order to deal with the non-square non-minimum phase discrete-time system, we blend the classical control methodology and the generalized LQDT design such that the non-square non-minimum phase discrete-time system has a desired minimum-phase-like tracking performance for a given arbitrary reference trajectory with drastic variations. In addition, we construct a state and disturbance estimator using discrete-time proportional plus integral observer to estimate both the system state and the unknown external disturbance for the discrete-time systems with an unknown external disturbance. Then, by applying the generalized LQDT design, design a proportional plus integral observer-based LQDT with a high-gain property to have a desired tracking performance. A new iterative learning LQDT with input constraint for the discrete-time repetitive system with a direct-feedthrough term, unknown process disturbance, and unknown measurement noise, has been presented. By the initialization of the proposed iterative learning control (ILC), it can converge in one epoch for a desired tracking performance. Besides, we also present a simple and effective method to deal with the more general discrete-time system which has a direct-feedthrough term, unknown process disturbance, and unknown measurement noise.

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31

Li, Te. "Eliminating the Internal Instability in Iterative Learning Control for Non-minimum Phase Systems." Thesis, 2017. https://doi.org/10.7916/D8X92GX5.

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Iterative Learning Control (ILC) iterates with a real world control system repeatedly performing the same task. It adjusts the control action based on error history from the previous iteration, aiming to converge to zero tracking error. ILC has been widely used in various applications due to its high precision in trajectory tracking, e.g. semiconductor manufacturing sensors that repeatedly perform scanning maneuvers. Designing effective feedback controllers for non-minimum phase (NMP) systems can be challenging. Applying Iterative Learning Control (ILC) to NMP systems is particularly problematic. Asking for zero error at sample times usually involves inverting the control system. However, the inverse process is unstable when the system has NMP zeros. The control action will grow exponentially every time step, and the error between time steps also grows exponentially. If there are NMP zeros on the negative real axis, the control action will alternate its sign every time step. ILC must be digital to use previous run data to improve the tracking error in the current run. There are two kinds of NMP digital systems, ones having intrinsic NMP zeros as images of continuous time NMP zeros, and NMP sampling zeros introduced by discretization. Two ILC design methods have been investigated in this thesis to handle NMP sampling zeros, producing zero tracking error at addressed sample times: (1) One can simply start asking for zero error after a few initial time steps, like using multiple zero order holds for the first addressed time step only (2) Or increase the sample rate, ask for zero error at the original rate, making two or more zero order holds per addressed time step. The internal instability can be manifested by the singular value decomposition of the input-output matrix. Non-minimum phase systems have particularly small singular values which are related to the NMP zeros. The aim is to eliminate these anomalous singular values. However, when applying the second approach, there are cases that the original anomalous singular values are gone, but some new anomalous singular values appear in the system matrix that cause difficulties to the inverse problem. Not asking for zero error for a small number of initial addressed time steps is shown to eliminate all anomalous singular values. This suggests that a more accurate statement of the second approach is: using multiple zero order holds per addressed time step, and eliminating a few initial addressed time steps if there are new anomalous singular values. We also extend the use of these methods to systems having intrinsic NMP zeros. By modifying ILC laws to perform pole-zero cancellation inside the unit circle, we observe that all of the rules for sampling zeros are effective for intrinsic zeros. Hence, one can now achieve convergence to zero tracking error at addressed time steps in ILC of NMP systems with a well behaved control action. In addition, this thesis studies the robustness of the two approaches along with several other candidate approaches with respect to model parameter uncertainty. Three classes of ILC laws are used. Both approaches show great robustness. Quadratic cost ILC is seen to have substantially better robustness to parameter uncertainty than the other laws.

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32

Lee, Chia-Chi, and 李家綺. "Control of Nonlinear Non-minimum Phase Process Systems Using An Adaptive Single Neural Controller." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/05041398706840632457.

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碩士
逢甲大學
化學工程學所
92
Abstract In this thesis, a nonlinear control scheme which integrates an autotuning single neural controller (SNC) and a statically equivalent output map is proposed for nonlinear non-minimum phase processes. The role of the incorporated statically equivalent output map is to compensate for the undesirable inverse response behavior, which therefore enables the SNC to control the nonlinear non-minimum phase processes in an autonomous and interactive way by merely observing the process output errors. The potential use of a sliding observer for estimating the unmeasurable states is also investigated in this thesis. Moreover, the present scheme is extended to multivariable case, where a decentralized SNC control system is presented. Extensive simulation results reveal that the proposed nonlinear control strategy is effective and applicable in overcoming the negative effects of inverse response, plant/model mismatch and unmeasured disturbance. Due to its good performance and significant control structure, the proposed autotuning SNC control scheme appears to be an effective and promising approach to the direct control of nonlinear non-minimum phase process systems.

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33

Han-KuanHuang and 黃瀚寬. "Sliding Mode Tracker Design for Non-minimum Phase Systems with Nonlinear Disturbances: Zero Assignment Method." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/6m3339.

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34

Zih-WeiLin and 林子為. "A new robust PI-based optimal linear quadratic state-estimate tracker for discrete-time non-square non-minimum phase systems." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/v34xzb.

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35

Li, Ying-Guo, and 李螢國. "The Study of Model Approximation Using a Second-Order System with Underdamped Transient and Non-minimum Phase." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/11454079165399164815.

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碩士
國立高雄應用科技大學
化學工程與材料工程系碩士在職專班
103
The thesis investigates the problem of model approximation for high-order systems with underdamped transient and non-minimum phase. At first, a few characteristic points are picked out from the step response of a high-order system. Then, random combination of these points is used to find a second-order approximant with underdamped transient and non-minimum phase. Finally, the impulse response energy and the integral of square error are used as performance indices to determine the fitness of the proposed approximants. The simulation results show that the first valley point, the point of the first , and the point of the first is the best combination to obtain the suitable approximant.

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36

Narang, Anshu. "Analysis and Control of Non-Affine, Non-Standard, Singularly Perturbed Systems." Thesis, 2012. http://hdl.handle.net/1969.1/148104.

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This dissertation addresses the control problem for the general class of control non-affine, non-standard singularly perturbed continuous-time systems. The problem of control for nonlinear multiple time scale systems is addressed here for the first time in a systematic manner. Toward this end, this dissertation develops the theory of feedback passivation for non-affine systems. This is done by generalizing the Kalman-Yakubovich-Popov lemma for non-affine systems. This generalization is used to identify conditions under which non-affine systems can be rendered passive. Asymptotic stabilization for non-affine systems is guaranteed by using these conditions along with well-known passivity-based control methods. Unlike previous non-affine control approaches, the constructive static compensation technique derived here does not make any assumptions regarding the control influence on the nonlinear dynamical model. Along with these control laws, this dissertation presents novel hierarchical control design procedures to address the two major difficulties in control of multiple time scale systems: lack of an explicit small parameter that models the time scale separation and the complexity of constructing the slow manifold. These research issues are addressed by using insights from geometric singular perturbation theory and control laws are designed without making any assumptions regarding the construction of the slow manifold. The control schemes synthesized accomplish asymptotic slow state tracking for multiple time scale systems and simultaneous slow and fast state trajectory tracking for two time scale systems. The control laws are independent of the scalar perturbation parameter and an upper bound for it is determined such that closed-loop system stability is guaranteed. Performance of these methods is validated in simulation for several problems from science and engineering including the continuously stirred tank reactor, magnetic levitation, six degrees-of-freedom F-18/A Hornet model, non-minimum phase helicopter and conventional take-off and landing aircraft models. Results show that the proposed technique applies both to standard and non-standard forms of singularly perturbed systems and provides asymptotic tracking irrespective of the reference trajectory. This dissertation also shows that some benchmark non-minimum phase aerospace control problems can be posed as slow state tracking for multiple time scale systems and techniques developed here provide an alternate method for exact output tracking.

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37

Yen, Chia-Te, and 嚴家德. "Cacaded H-infinity Design for Doubly Coprime Factorization Disturbance Observer and Controller Applied to Non-minimum Phase MIMO Systems." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/26taua.

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碩士
國立交通大學
機械工程系所
103
In this thesis, one provides an approach which can be used in non-minimum phase and MIMO systems based on cascade design method. In mechanical control, we can eliminate the disturbance at low-frequency and resist the uncertainty at high-frequency by using disturbance observer. The classical DOB has some constrains when it is used because it only can be applied to minimum phase. Therefore, doubly coprime disturbance observer (DCFDOB) was proposed a few years ago, it can be used in non-minimum phase systems. The approach which is proposed in this thesis, it transforms the inner-loop disturbance observer and outer-loop controller problems into two mixed-sensitivity problems, called improving cascade design method. This method can help find a DOB with maximum bandwidth, it has more efficiency of eliminating disturbance and good robustness. Also, the outer controller has allowable response under robustly stable. By using DCFDOB to replace the classical DOB, it can be used more widely in mechanical control, e.g. on non-minimum phase and MIMO systems. Besides, there are some methods which can be applied to non-minimum phase systems, arranged in this thesis. To test the design results, using MATLAB / Simulink to simulate the design parameter and to run the experiments after getting a set of DOB and controller. As a result, the DOB and controller by this approach eliminates disturbance more effectively and keeps tracking performance under robust stability.

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Dissertations / Theses on the topic 'Non minimum phase plant'

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