Total harmonic distortion analysis of inverter fed induction motor drive using neuro fuzzy type-1 and neuro fuzzy type-2 controllers

Introduction. When the working point of the indirect vector control is constant, the conventional speed and current controllers operate effectively. The operating point, however, is always shifting. In a closed-system situation, the inverter measured reference voltages show higher harmonics. As a result, the provided pulse is uneven and contains more harmonics, which enables the inverter to create an output voltage that is higher. Aim. A space vector modulation (SVM) technique is presented in this paper for type-2 neuro fuzzy systems. The inverter’s performance is compared to that of a neuro fuzzy type-1 system, a neuro fuzzy type-2 system, and classical SVM using MATLAB simulation and experimental validation. Methodology. It trains the input-output data pattern using a hybrid-learning algorithm that combines back-propagation and least squares techniques. Input and output data for the proposed technique include information on the rotation angle and change of rotation angle as input and output of produced duty ratios. A neuro fuzzy-controlled induction motor drive’s dynamic and steady-state performance is compared to that of the conventional SVM when using neuro fuzzy type-2 SVM the induction motor, performance metrics for current, torque, and speed are compared to those of neuro fuzzy type-1 and conventional SVM. Practical value. The performance of an induction motor created by simulation results are examined using the experimental validation of a dSPACE DS-1104. For various switching frequencies, the total harmonic distortion of line-line voltage using neuro fuzzy type-2, neuro fuzzy type-1, and conventional based SVMs are provided. The 3 hp induction motor in the lab is taken into consideration in the experimental validations.Вступ. Коли робоча точка непрямого векторного управління стала, традиційні регулятори швидкості та струму працюють ефективно. Проте робоча точка постійно змінюється. У ситуації закритої системи виміряна інвертором опорна напруга показує вищі гармоніки. В результаті імпульс, що подається, нерівномірний і містить більше гармонік, що дозволяє інвертору створювати більш високу вихідну напругу. Мета. У цій статті представлена методика просторової векторної модуляції (SVM) для нейронечітких систем типу 2. Продуктивність інвертора порівнюється з продуктивністю нейронечіткої системи типу 1, нейронечіткої системи типу 2 та класичної SVM з використанням моделювання MATLAB та експериментальної перевірки. Методологія. Навчається шаблон даних введення-виводу, використовуючи алгоритм гібридного навчання, який поєднує у собі методи зворотного поширення помилки та методу найменших квадратів. Вхідні та вихідні дані для запропонованої методики включають інформацію про кут повороту і зміну кута повороту як отримані вхідні і вихідні коефіцієнти заповнення. Динамічні характеристики приводу асинхронного двигуна з нейронечітким управлінням порівнюються з характеристиками звичайного SVM. При використанні нейронечіткого SVM типу 2 асинхронний двигун, показники продуктивності по струму обертаючого моменту і швидкості порівнюються з показниками приводу асинхронного двигуна з нейронечітким управлінням типу 1 та традиційного SVM. Практична цінність. Продуктивність асинхронного двигуна, створеного за результатами моделювання, досліджується з використанням експериментальної перевірки dSPACE DS-1104. Для різних частот перемикання розраховуються загальні гармонічні спотворення лінійної напруги з використанням нейронечіткого управління  типу 2, нейронечіткого управління типу 1 і традиційного SVM. Асинхронний двигун потужністю 3 л.с. у лабораторії враховується під час експериментальних перевірок

Nova shema za izravno upravljanje momentom asinkronih motora napajanih iz trofaznog izmjenjivača

This paper presents a novel controller based on Direct Torque Control (DTC) strategy. This controller is designed to be applied in the control of Induction Motors (IM) fed with a three-level Voltage Source Inverter (VSI). This type of inverter has several advantages over the standard two-level VSI, such as a greater number of levels in the output voltage waveforms, lower dV/dt, less harmonic distortion in voltage and current waveforms and lower switching frequencies. In the new controller, torque and stator flux errors are used together with the stator flux angular frequency to generate a reference voltage vector. Experimental results of the novel system are presented and compared with those obtained for Classical DTC system employing a two-level VSI. The new controller is shown to reduce the ripple in the torque and flux responses. Lower current distortion and switching frequency of the semiconductor devices are also obtained in the new system presented.U ovome se članku opisuje novi regulator zasnovan na strategiji izravnog upravljanja momentom i razvijen za primjenu u upravljanju asinkronim motorima napajanim iz trorazinskih izmjenjivača napona. Taj tip izmjenjivača ima nekoliko prednosti u odnosu na standardne dvorazinske izmjenjivače napona, kao što je veći broj razina u izlaznom valnom obliku napona, niži du/dt, manja distorzija harmonika u valnim oblicima napona i struje i niže frekvencije komutacije. U novom regulatoru moment i pogreške u statorskom toku koriste se zajedno s kutnom frekvencijom statora za tvorbu referentne vrijednosti vektora napona. Eksperimentalni su rezultati novog sustava prikazani i uspoređeni s rezultatima klasičnog sustava koji koristi dvorazinski pretvarač napona. Novi regulator pokazuje smanjeni šum u odzivima momenta i toka motora. U predloženom je sustavu također postignuta i manja distorzija struje i manja frekvencija komutacije poluvodičkih sklopova

Development and Implementation of Some Controllers for Performance Enhancement and Effective Utilization of Induction Motor Drive

The technological development in the field of power electronics and DSP technology is rapidly changing the aspect of drive technology. Implementations of advanced control strategies like field oriented control, linearization control, etc. to AC drives with variable voltage, and variable frequency source is possible because of the advent of high modulating frequency PWM inverters. The modeling complexity in the drive system and the subsequent requirement for modern control algorithms are being easily taken care by high computational power, low-cost DSP controllers. The present work is directed to study, design, development, and implementation of various controllers and their comparative evaluations to identify the proper controller for high-performance induction motor (IM) drives. The dynamic modeling for decoupling control of IM is developed by making the flux and torque decoupled. The simulation is carried out in the stationary reference frame with linearized control based on state-space linearization technique. Further, comprehensive and systematic design procedures are derived to tune the PI controllers for both electrical and mechanical subsystems. However, the PI-controller performance is not satisfactory under various disturbances and system uncertainties. Also, precise mathematical model, gain values, and continuous tuning are required for the controller design to obtain high performance. Thus, to overcome these drawbacks, an adapted control strategy based on Adaptive Neuro-Fuzzy Inference System (ANFIS) based controller is developed and implemented in real-time to validate different control strategies. The superiority of the proposed controller is analyzed and is contrasted with the conventional PI controller-based linearized IM drive. The simplified neuro-fuzzy control (NFC) integrates the concept of fuzzy logic and neural network structure like conventional NFC, but it has the advantages of simplicity and improved computational efficiency over conventional NFC as the single input introduced here is an error instead of two inputs error and change in error as in conventional NFC. This structure makes the proposed NFC robust and simple as compared to conventional NFC and thus, can be easily applied to real-time industrial applications. The proposed system incorporated with different control methods is also validated with extensive experimental results using DSP2812. The effectiveness of the proposed method using feedback linearization of IM drive is investigated in simulation as well as in experiment with different working modes. It is evident from the comparative results that the system performance is not deteriorated using proposed simplified NFC as compared to the conventional NFC, rather it shows superior performance over PI-controller-based drive. A hybrid fuel cell (FC) supply system to deliver the power demanded by the feedback linearization (FBL) based IM drive is designed and implemented. The modified simple hybrid neuro-fuzzy sliding-mode control (NFSMC) incorporated with the intuitive FBL substantially reduces torque chattering and improves speed response, giving optimal drive performance under system uncertainties and disturbances. This novel technique also has the benefit of reduced computational burden over conventional NFSMC and thus, suitable for real-time industrial applications. The parameters of the modified NFC is tuned by an adaptive mechanism based on sliding-mode control (SMC). A FC stack with a dc/dc boost converter is considered here as a separate external source during interruption of main supply for maintaining the supply to the motor drive control through the inverter, thereby reducing the burden and average rating of the inverter. A rechargeable battery used as an energy storage supplements the FC during different operating conditions of the drive system. The effectiveness of the proposed method using FC-based linearized IM drive is investigated in simulation, and the efficacy of the proposed controller is validated in real-time. It is evident from the results that the system provides optimal dynamic performance in terms of ripples, overshoot, and settling time responses and is robust in terms of parameters variation and external load

Nova shema za izravno upravljanje momentom asinkronih motora napajanih iz trofaznog izmjenjivača

This paper presents a novel controller based on Direct Torque Control (DTC) strategy. This controller is designed to be applied in the control of Induction Motors (IM) fed with a three-level Voltage Source Inverter (VSI). This type of inverter has several advantages over the standard two-level VSI, such as a greater number of levels in the output voltage waveforms, lower dV/dt, less harmonic distortion in voltage and current waveforms and lower switching frequencies. In the new controller, torque and stator flux errors are used together with the stator flux angular frequency to generate a reference voltage vector. Experimental results of the novel system are presented and compared with those obtained for Classical DTC system employing a two-level VSI. The new controller is shown to reduce the ripple in the torque and flux responses. Lower current distortion and switching frequency of the semiconductor devices are also obtained in the new system presented.U ovome se članku opisuje novi regulator zasnovan na strategiji izravnog upravljanja momentom i razvijen za primjenu u upravljanju asinkronim motorima napajanim iz trorazinskih izmjenjivača napona. Taj tip izmjenjivača ima nekoliko prednosti u odnosu na standardne dvorazinske izmjenjivače napona, kao što je veći broj razina u izlaznom valnom obliku napona, niži du/dt, manja distorzija harmonika u valnim oblicima napona i struje i niže frekvencije komutacije. U novom regulatoru moment i pogreške u statorskom toku koriste se zajedno s kutnom frekvencijom statora za tvorbu referentne vrijednosti vektora napona. Eksperimentalni su rezultati novog sustava prikazani i uspoređeni s rezultatima klasičnog sustava koji koristi dvorazinski pretvarač napona. Novi regulator pokazuje smanjeni šum u odzivima momenta i toka motora. U predloženom je sustavu također postignuta i manja distorzija struje i manja frekvencija komutacije poluvodičkih sklopova

Performance enhancement of direct torque control induction motor drive using space vector modulation strategy

Purpose. The main objective of this work is to demonstrate the advantages brought by the use of space vector modulation technique in the direct torque control of the induction motor. To achieve this purpose, two different direct torque control approaches (with space vector modulation) are proposed and studied from a comparative aspect with each other and with the conventional direct torque control. The novelty of this work consists in the employment of an Integral-Proportional (IP) speed controller in the two proposed direct torque control approaches and a more in-depth evaluation for their performance mainly the switching frequency of inverter semiconductor components and motor torque ripples. Methods. Two different direct torque control approaches that use the space vector modulation strategy and/or fuzzy-logic control, are described in detail and simulated with IP speed controller. The simulation experiments are carried out using Matlab/Simulink software and/or fuzzy-logic tools. Results. Practical value. Comparison results show that the two proposed direct torque control structures (with space vector modulation) exhibit a large reduction in torque ripples and can also avoid random variation problem of switching frequency (over a wide range of speed or torque control). On the other hand, the use of IP speed regulator ensured good dynamic performance for the drive system as well as considerably minimized peak overshoot in the speed response. Practically all of these benefits are achieved while retaining the simplicity and the best dynamic characteristics of the classical direct torque control, especially with the modified direct torque control approach in which the design or implementation requires minimal computational effort.Мета. Основна мета даної роботи – продемонструвати переваги використання методу модуляції просторового вектора при прямому регулюванні крутного моменту асинхронного двигуна. Для досягнення цієї мети запропоновано два різних підходи до прямого управління крутним моментом (з модуляцією просторового вектора), які досліджуються з порівняльної точки зору  одного з іншим, а також зі звичайним прямим керуванням крутним моментом. Новизна роботи полягає у використанні інтегрально-пропорційного (IП) регулятора швидкості в двох запропонованих підходах до прямого регулювання крутного моменту та більш поглибленій оцінці їх ефективності, головним чином, частоти перемикань напівпровідникових компонентів інвертора та пульсації крутного моменту двигуна. Методи. Два різних підходи до прямого керування крутним моментом, які використовують стратегію модуляції просторового вектора та/або керування нечіткою логікою, детально описані та змодельовані за допомогою ІП-регулятора швидкості. Обчислювальні експерименти проводяться з використанням програмного забезпечення Matlab/Simulink та/або інструментів нечіткої логіки. Результати. Практична цінність. Результати порівняння показують, що дві запропоновані структури прямого керування крутним моментом (з модуляцією просторового вектора) демонструють значне зниження пульсації крутного моменту, а також можуть уникнути проблеми випадкових змін частоти перемикання (у широкому діапазоні регулювання швидкості або крутного моменту). З іншого боку, використання ІП-регулятора швидкості забезпечило хороші динамічні характеристики для приводної системи, а також значно знизило пікове перевищення швидкості. Практично всі ці переваги досягаються при збереженні простоти та найкращих динамічних характеристик класичного прямого керування крутним моментом, особливо з модифікованим підходом прямого керування крутним моментом, при якому проектування або впровадження вимагає мінімальних обчислювальних витрат

Optimal Control Technique of an Induction Motor

The squirrel cage induction motor (IM) has many advantages over other types of electric technique (FOC), classical direct torque control (DTC), and direct torque control with space vector modulation (DTC-SVM) is carried out. The objective of this paper is to decouple the mechanical quantities such as torque and flux in a way similar to the DC motor control. And also to minimize the torque and flux modulation of the IM. Torque oscillations can cause mechanical resonances and consequently acoustic noise, hence damaging the machine. Reducing the switching frequency significantly minimizes switching losses. The DTC-SVM control technique improves the performance of conventional DTC, which is characterized by low torque and flux modulation as well as a fixed switching frequency. Simulation results in MATLAB show that torque and current ripples are reduced with the improved DTC. DTC-SVM used for the traction control system is easy to implement in digital systems and also allows to move the photovoltaic panels according to the position of maximum sunshine to extract the maximum energy with high efficiency from the system

Speed Control of Parallel Connected DSIM Fed by Six Phase Inverter with IFOC Strategy Using ANFIS

This paper describe the presentation of an IM for high load and high-power applications, this kind of applications the motor have a complex coupling between the field and torque. This can be achieve with assist of Indirect Field Oriented Control (IFOC) and parallel connection of two motors. The benefit is that parallel connection can provide the decoupled control of flux and torque for each motor and their concert in different operating environments. The Speed control of two Double Star Induction Motors working in parallel configuration with IFOC using a Fuzzy Logic Controller (FLC) and Adaptive Neuro Fuzzy Inference (ANFIS) controller is investigate in different operating environments. The two motors are connected in parallel at the output of a single six-phase PWM based inverter fed from a DC source. Performance of the projected method under load disturbances is studied through simulation using a MATLAB and evaluation of speed response of two controllers is analyzed. &nbsp

High-performance motor drives

This article reviews the present state and trends in the development of key parts of controlled induction motor drive systems: converter topologies, modulation methods, as well as control and estimation techniques. Two- and multilevel voltage-source converters, current-source converters, and direct converters are described. The main part of all the produced electric energy is used to feed electric motors, and the conversion of electrical power into mechanical power involves motors ranges from less than 1 W up to several dozen megawatts

To develop an efficient variable speed compressor motor system

This research presents a proposed new method of improving the energy efficiency of a Variable Speed Drive (VSD) for induction motors. The principles of VSD are reviewed with emphasis on the efficiency and power losses associated with the operation of the variable speed compressor motor drive, particularly at low speed operation.The efficiency of induction motor when operated at rated speed and load torque is high. However at low load operation, application of the induction motor at rated flux will cause the iron losses to increase excessively, hence its efficiency will reduce dramatically. To improve this efficiency, it is essential to obtain the flux level that minimizes the total motor losses. This technique is known as an efficiency or energy optimization control method. In practice, typical of the compressor load does not require high dynamic response, therefore improvement of the efficiency optimization control that is proposed in this research is based on scalar control model.In this research, development of a new neural network controller for efficiency optimization control is proposed. The controller is designed to generate both voltage and frequency reference signals imultaneously. To achieve a robust controller from variation of motor parameters, a real-time or on-line learning algorithm based on a second order optimization Levenberg-Marquardt is employed. The simulation of the proposed controller for variable speed compressor is presented. The results obtained clearly show that the efficiency at low speed is significant increased. Besides that the speed of the motor can be maintained. Furthermore, the controller is also robust to the motor parameters variation. The simulation results are also verified by experiment