Design of second order sliding mode observer based equivalent Back-EMF for rotor position estimation of PMSM

This study introduces a scheme to estimate rotor position by the use of an Equal electromotive force (EMF) model of a synchronous machine. This use could be substituted by a sliding-mode observer (SMO) according to an equal EMF for superior reference speed tracking. There is an algorithm of the second order sliding-mode-control (SO-SMC) in controlling speed of permanent magnet synchronous motor (PMSM). This is by the use of the proportional plus-integral PI control sliding plane. The current work discusses the PMSM, which follows field-oriented appears. In addition, there are SO-SMC laws and PI sliding plans. This paper shows that the proposed high-speed PMSM sensorless speed control is valid by MATLAB simulations

POWER QUALITY CONTROL AND COMMON-MODE NOISE MITIGATION FOR INVERTERS IN ELECTRIC VEHICLES

Inverters are widely utilized in electric vehicle (EV) applications as a major voltage/current source for onboard battery chargers (OBC) and motor drive systems. The inverter performance is critical to the efficiency of EV system energy conversion and electronics system electro-magnetic interference (EMI) design. However, for AC systems, the bandwidth requirement is usually low compared with DC systems, and the control impact on the inverter differential-mode (DM) and common-mode (CM) performance are not well investigated. With the wide-band gap (WBG) device era, the switching capability of power electronics devices drastically improved. The DM/CM impact that was brought by the WBG device-based inverter becomes more serious and has not been completely understood. This thesis provides an in-depth analysis of on-board inverter control strategies and the corresponding DM/CM impact on the EV system. The OBC inverter control under vehicle-to-load (V2L) mode will be documented first. A virtual resistance damping method minimizes the nonlinear load harmonics, and a neutral balancing method regulates the unbalanced load impact through the fourth leg. In the motor drive system, a generalized CM voltage analytical model and a current ripple prediction model are built for understanding the system CM and DM stress with respect to different modulation methods, covering both 2-level and 3-level topologies. A novel CM EMI damping modulation scheme is proposed for 6-phase inverter applications. The performance comparison between the proposed methods and the conventional solution is carried out. Each topic is supported by the corresponding hardware platform and experimental validation

Projeto, modelagem, simulação, construção e controle de um veículo de duas rodas pêndulo invertido

This work aims to obtain the static equilibrium of the vertical position of an two-wheeled inverted pendulum vehicle using PID controllers obtained through classical techniques as experimental tuning and the root locus method and also using more sophisticated controllers such as the Fuzzy controller . For this, the design of a new two-wheeled vehicle was realized, and its construction is detailed throughout the work. With this vehicle it was possible to obtain good results with the presented control techniques. The nonlinear dynamic model of the two-wheeled inverted pendulum is obtained through the Newton-Euler formulation. Since it is not always possible to keep the vehicle within the linearization conditions, the nonlinear model obtained was used to simulate the vehicle using the 4th order Runge-Kutta method, to obtain a result similar to the actual behavior of the vehicle. After the identification of the vehicle’s parameters, the simulation and real-time responses were compared and using statistical tests with 95% confidence, it was observed that the responses are not different for most the controllers. When designing a controller using the linear model, depending on the vehicle’s operating conditions, this controller might not accomplish the project requirements, so it was also proposed a way to adapt a PID controller obtained by the root locus method to the nonlinear model using the simulation, and a substantial improvement of the controller with adapted parameters was observed.Trabalho de Conclusão de Curso (Graduação)Esse trabalho visa obter o equilíbrio estático da posição vertical de um veículo de duas rodas do tipo pêndulo invertido, utilizando controladores PIDs obtidos através de técnicas clássicas como a sintonia experimental e o método do lugar das raízes e utilizando também controladores mais sofisticados como o controlador Fuzzy. Para isso, foi realizado o projeto de um novo veículo de duas rodas, e sua construção é detalhada ao longo do trabalho. Com esse veículo foi possível obter bons resultados com as técnicas de controle apresentadas. O veículo foi modelado utilizando o formalismo de Newton-Euler. Como nem sempre é fácil manter o veículo dentro das condições de linearização o modelo não linear obtido foi utilizado para a simulação do veículo com auxílio do método numérico Runge-Kutta de 4° ordem, para obter um resultado mais semelhante possível do comportamento real do veículo. Após a identificação dos parâmetros do veículo as respostas da simulação e em tempo real foram comparadas e utilizando testes estatísticos com 95% de confiança foi observado que as respostas não são diferentes para a maioria dos controladores. Ao projetar um controlador utilizando o modelo linear, dependendo das condições de operação do veículo esse controlador poderá não cumprir os requisitos de projeto, dessa forma também foi proposto uma forma de adaptar um controlador PID obtido pelo método do lugar das raízes ao modelo não linear utilizando a simulação, e foi observado uma melhora substancial do controlador com parâmetros adaptados

Sintonización de controladores PID para control de velocidad de motores de corriente continua mediante algoritmos genéticos.

Este documento presenta el desarrollo de un algoritmo genético para optimización de ganancias de un controlador PID (proporcional, integral, derivativo) aplicado al control de velocidad de un motor de corriente directa. El algoritmo fue desarrollado en código Python. Produce un buen desempeño con pocas iteraciones debido a la generación de la población inicial a partir de las reglas de sintonización de Ziegler & Nichols. El controlador obtenido mediante la aplicación del algoritmo genético es comparado con los métodos convencionales de sintonización de Ziegler y Nichols, CohenCoon y AMIGO, en términos de tiempo de establecimiento, sobre oscilación máxima y robustez. Los resultados obtenidos permiten concluir que se minimiza la sobre oscilación máxima y el tiempo de establecimiento mediante el uso del controlador obtenido mediante el algoritmo genético, que a su vez presenta una mejor robustez en comparación con los controladores obtenidos con los otros métodos.This document presents the development of a genetic algorithm for optimizing the gains of a PID (proportional, integral, derivative) controller applied to the speed control of a direct current motor. The algorithm was developed in Python code. It produces a good performance with few iterations due to the generation of the initial population based on the tuning rules of Ziegler & Nichols. The controller obtained through the application of the genetic algorithm is compared with the conventional tuning methods of Ziegler and Nichols, CohenCoonand AMIGO, in terms of establishment time, maximum overshoot and robustness. The obtained results allow to conclude that the maximum overshoot and the establishment time are minimized by using the controller obtained through the genetic algorithm, which in turn has a better robustness compared to the controllers obtained with the other methods

Stability Analysis and Robust Controller Design of Indirect Vector Controlled Induction Motor

The thesis considers stability analysis and controller design through different performance measures for indirect vector controlled induction motor (IVCIM).These problems are known to be complex due to nonlinearity, large order and multi-loop scenario. Some new approaches and results on IVCIM are proposed in this work. IVCIM dynamics is well known for having different bifurcation behavior, viz., saddle-node, Hopf, Bogdanov–Takens and Zero–Hopf bifurcations due to rotor resistance variation. These bifurcations affect the control performance and may lead to stalling or permanent damage of motor. A numerical analysis of these bifurcations for proportional integral (PI) controlled IVCIM is made in this thesis using full-order induction motor model (stator dynamics is included). This analysis aids to determine the allowable bifurcation parameter variation range as well as suitable choice of speed-loop gains to avoid these. Some new observations on the bifurcation behavior are made. Simulation and experimental results are presented validating the bifurcation behaviors. For improving dynamic performance in the presence of load torque and rotor resistance variation, a new method for designing PI gains is proposed for IVCIM. The inner-loop current PI controllers are tuned simultaneously along with the speed controller. This method is implemented using a static output feedback scheme in which iterative linear matrix inequality (ILMI) based∞control technique is employed. Such a design makes stator currents and speed response to be robust against rotor resistance and load variations. A comparison between proposed design and a conventional one is shown using simulation and experimental results that validate the superiority of the proposed approach. Owing to multi-loop and nonlinear system behavior, IVCIM dynamics is known to have coupling in between the two inner-loop stator current components (flux and torque). Such coupling affects the dynamic torque output of the motor. Decoupling of the stator currents are important for smoother torque response of IVCIM. Conventionally, additional feedforward decoupler is used to take care of the coupling that requires exact knowledge of the motor parameters and additional circuitry or signal processing. A method is proposed to design the regulating PI gains while minimizing coupling without any requirement of additional decoupler. The variation of the coupling terms for change in load torque is considered as the performance measure. The same ILMI based∞control design approach is used to obtain the controller gains. A comparison between the conventional feedforward decoupling and proposed decoupling scheme is presented through simulation and experimental results that establish the effectiveness of the proposed method riding over its simplicity. Finally, since the PI controller can yield limited performance, a dynamic controller is designed for the IVCIM drive system. In the design process, iron-loss dynamics are incorporated into induction motor model to fetch benefit through better performance. A sequential design method is used for the controller design in which, first, the inner-loop controllers are designed. The designed inner-loop controllers is then used for designing the outer speed-loop controller. The proposed design employs ILMI based∞control design for dynamic output feedback controller that makes stator currents and speed response to be robust against disturbances. A comparison among proposed dynamic controller design, PI controller and compensator design is shown using simulation and experimental results demonstrate enhanced performance of the proposed controller and suitability for industrial purpose

Development and implementation of fuzzy controller in biodiesel production

Orientador: Flavio Vasconcelos da SilvaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia QuimicaResumo: A crescente utilização do biodiesel como combustível renovável e, principalmente, as situações de operação transiente, de característica complexa e não-linear, motivaram a implementação de um controlador digital avançado neste processo. O controlador avançado foi implementado em computador através de um sistema de comunicação digital, visando manter a temperatura da mistura reacional em 50 °C. A temperatura é uma variável importante deste processo devido à influência direta na taxa de conversão do óleo em biodiesel. Óleo de soja foi utilizado como fonte de ácidos graxos, além do uso do álcool etílico anidro e ácido sulfúrico como reagentes. A reação química foi acompanhada durante 1 hora de batelada visando assegurar uma boa conversão do óleo (acima de 90%). Neste trabalho, além do controlador avançado também foi implementado o controlador PID. Os parâmetros de sintonia do controlador PID foram obtidos em malha aberta e auxiliaram a sintonia do controlador fuzzy. Durante a etapa de sintonia fina do controlador fuzzy foram alteradas as funções de pertinência, o universo de discurso e a base de regras. A implementação do controlador fuzzy apresentou-se como uma ferramenta apropriada para o controle da temperatura reacional devido às complexidades advindas das variações dos parâmetros deste processo. A análise comparativa do desempenho dos controladores fuzzy e PID aplicados à produção de biodiesel comprovaram isso. O uso do controlador fuzzy reduziu o consumo de energia elétrica durante a batelada em 10% quando comparado ao parâmetro obtido para o controlador PID e também reduziu o tempo necessário para atingir a máxima conversão do óleo em biodiesel em 15 minAbstract: The increasing use of biodiesel as a renewable fuel, and mainly because of their nonlinearity and time varying properties this work aimed the implementation and the development of an automation system based in fuzzy logic. In this work, the fuzzy controller is applied in the maintenance of the temperature of bulk at 50?C, using digital system. The control of the temperature in this process is important to guarantee the final quality of biodiesel. Soybean oil was used like source of fatty acids, ethanol and sulfuric acid were used like reagents. This reaction occured during an hour to can achieved high conversion (above 90%). The PID controller tuning parameters were obtained via open-loop experiments. The tuning the fuzzy controller can be achieved by modifying the rules, the discurse universe and the pertinence functions. Due the complexity and the nonlinearity of this reaction, the results of this study showed the effectiveness of fuzzy controller. The fuzzy controller reduced the energy consumption (10% smaller) and the batch time (15 min smaller) when compared to a PID controllerDoutoradoSistemas de Processos Quimicos e InformaticaDoutor em Engenharia Químic

Studi Pengendalian Frekuensi Menggunakan Logika Fuzzy Di PLTU Paiton

dalam pengaturan frekuensi pada sistem tenaga listrik dapat dilakukan dengan metode-metode kontrol. namun dalam penelitian ini akan di coba pengendalian frekuensi dengan menggunakan logika fuzzy. dasar pemikiran ini di ambil dengan bertitik tolak kepada beberapa pertimbangan yaitu di lihat dari keunggulan logika fuzz

Modeling the effects of belt compliance, backlash, and slip on web tension and new methods for decentralized control of web processing lines

Scope and Method of Study: Non-ideal behavior of web process lines and new methods for regulation of web tension and web velocity are investigated. The non-ideal behavior considered includes the compliance and backlash in the transmission system and slippage of web over a roller. The effect of non-ideal elements on the controlled web tension is examined. Dynamic models are developed and analyzed to bring out the effect of non-ideal elements on controlled web tension. A method of mitigating the effect of backlash on controlled web tension is proposed. Effect of web slippage over a roller on span tension dynamics is investigated. The web tension and velocity dynamics are systematically laid down. Two decentralized control schemes viz., a non-adaptive scheme and an adaptive scheme are proposed for web tension/velocity regulation. Experimental study is conducted to validate the results.Findings and Conclusions: The dynamic model of belt-pulley transmission system is derived by considering the tight side of the belt as a spring. The singular perturbation analysis reveals that using only the measured load side speed as the feedback signal is not desirable. A method of setting the proportional and integral gains of the speed controller is proposed. Starting from the first principles, a dynamic model of backlash is derived. This model accounts for the momentum of load during no contact. Using the model, a bound on the error due to presence of backlash is derived. The proposed bound agrees with results of experiments. The dynamic model of rewind section of a transmission system containing belt-compliance and backlash is derived. Analysis of the dynamic model shows that the mean rewind tension is shifted when there is backlash in the transmission system. This result agrees with experimental data. Further, the experiments show that providing an additional braking input on the rewind shaft is successful in mitigating the effects of backlash. The dynamics of idle roller, material rolls, and web spans are systematically laid out and a decentralized control scheme for the entire web process line is proposed. A method of calculating the equilibrium inputs and setting the reference tensions is derived. An exponentially stable non-adaptive scheme and an asymptotically stable adaptive scheme are presented. These schemes explicitly account for the varying inertia of the unwind/rewind rolls and compensate for unmatched interconnections. Experimental results show that the proposed methods offer superior web tension regulation as compared to the existing decentralized PI-control scheme