Control of A Switched Reluctance Motor Based on Asymmetric Converter and Digital Signal Controller for Forward and Reverse Mode

The Switched Reluctance Motor (SRM) is one of the best choices for industrial and electric vehicle applications, selected for its optimal performance. This is due to the advantages of SRM, including the use of permanent magnet-free technology and a simple construction consisting of an iron core on the rotor and stator windings. A rotary encoder is utilized to detect the rotor position due to its high precision. However, synchronization with the rotor position is required during installation to achieve optimal SRM performance. The rotor position obtained from the rotary encoder is processed by the digital signal controller to determine the firing angle on the rotor. The research objective is to control the SRM to rotate in both directions. To support this study, laboratory tests were conducted for validation by changing the phase sequence in the asymmetric converter, causing differences in the three-phase current waveforms for forward and reverse rotations. The results of this research show that the SRM can rotate bidirectionally

Control of A Switched Reluctance Motor Based on Asymmetric Converter and Digital Signal Controller for Forward and Reverse Mode

The Switched Reluctance Motor (SRM) is one of the best choices for industrial and electric vehicle applications, selected for its optimal performance. This is due to the advantages of SRM, including the use of permanent magnet-free technology and a simple construction consisting of an iron core on the rotor and stator windings. A rotary encoder is utilized to detect the rotor position due to its high precision. However, synchronization with the rotor position is required during installation to achieve optimal SRM performance. The rotor position obtained from the rotary encoder is processed by the digital signal controller to determine the firing angle on the rotor. The research objective is to control the SRM to rotate in both directions. To support this study, laboratory tests were conducted for validation by changing the phase sequence in the asymmetric converter, causing differences in the three-phase current waveforms for forward and reverse rotations. The results of this research show that the SRM can rotate bidirectionally

A Simple Method to Control The Excitation Angle for Switched Reluctance Motor

A switched reluctance motor (SRM) has been an alternative solution for electric drives because of its benefit features. The use of such a motor in electric vehicles (EVs) or hybrid electric vehicles (HEVs) requires a control strategy that is capable to develop high torque. SRMs are commonly available in the market with rotor position detectors embedded inside. Problems will appear when such detectors are not symmetrically installed because most of SRM control strategies are commonly based on them. Inaccurate pulses will be generated by the control circuit which finally takes effect on phase current commutation or the beginning of the excitation which is not on proper angle. The use of such detectors is just capable to give information of rotor position in common angles. Improvement for such problems can be done by generating pulses related to the rotor position in smooth angles. In this paper, a control strategy to produce excitation signals with proper angles for SRM stator winding is proposed. By using input capture facility that is commonly available in embedded system, excitation angles can be controlled precisely because a large number of pulses can be produced by the system. Accuracy level of this strategy is determined by TIMER period of embedded system and speed of SRM. To verify the analysis, laboratory experiments were done. They show that the proposed control strategy is capable to rotate the motor with better performance

Optimal Tracking Current Control of Switched Reluctance Motor Drives Using Reinforcement Q-learning Scheduling

In this paper, a novel Q-learning scheduling method for the current controller of switched reluctance motor (SRM) drive is investigated. Q-learning algorithm is a class of reinforcement learning approaches that can find the best forward-in-time solution of a linear control problem. This paper will introduce a new scheduled-Q-learning algorithm that utilizes a table of Q-cores that lies on the nonlinear surface of a SRM model without involving any information about the model parameters to track the reference current trajectory by scheduling infinite horizon linear quadratic trackers (LQT) handled by Q-learning algorithms. Additionally, a linear interpolation algorithm is proposed to guide the transition of the LQT between trained Q-cores to ensure a smooth response as state variables evolve on the nonlinear surface of the model. Lastly, simulation and experimental results are provided to validate the effectiveness of the proposed control scheme.Comment: 8 pages, 10 figure

Непряме полеорієнтоване керування двошнековим електромеханічним гідролізером

Goal. Development of a mathematical model of indirect field-oriented control of a twin-screw electromechanical hydrolyzer. Methodology. The paper presents a mathematical model of Indirect field-oriented control of twin-screw electromechanical hydrolyzer. The mathematical model was developed in the MATLAB / Simulink software environment. The determination of the main parameters of a twin-screw electromechanical hydrolyzer was carried out by developing a finite element model in the Comsol Multiphysics software environment. Results. Based on the results of a mathematical study, graphical dependences of the distribution of magnetic induction in the air gap of a ferromagnetic rotor, a spatial representation of the distribution of magnetic induction on a 3D model of a ferromagnetic rotor of a twin-screw electromechanical hydrolyzer were obtained. The results of finite element modeling were confirmed by a practical study of a mock-up of a ferromagnetic rotor of a twin-screw electromechanical hydrolyzer. By implementing the MATLAB / Simulink model, graphical dependences of the parameters of the ferromagnetic rotor of a twin-screw electromechanical hydrolyzer are obtained under the condition of a stepwise change in the torque and a cyclic change in the angular velocity. Originality. The paper presents an implementation of the method of indirect field-oriented control for controlling the ferromagnetic rotor of a twin-screw electromechanical hydrolyzer. The work takes into account the complex design of the ferromagnetic rotor of a twin-screw electromechanical hydrolyzer. Practical significance. The practical implementation of the results of mathematical modeling makes it possible to achieve effective control of a complex electromechanical system, allows further research to maintain the necessary parameters of the technological process and to develop more complex intelligent control systems in the future.У статті детально розглянуто конструктивні і електромагнітні особливості нестандартного електромеханічного перетворювача енергії – двошнекового електромеханічного гідролізера. Це технічний пристрій з поліфункціональними властивостями, здатний одночасно нагрівати, диспергувати, транспортувати, перемішувати та піддавати впливу магнітним полем в одному пристрої робочу сировину. Розроблено коло-польові та математичні моделі електромагнітних перехідних процесів цього пристрою. Основні параметри електромеханічної системи визначено шляхом кінцево-елементного моделювання та практичного дослідження феромагнітного ротора. В роботі представлено керування обертовим моментом та кутовою швидкістю феромагнітного ротора двошнекового електромеханічного гідролізера шляхом непрямого полеорієнтованого керування. Шляхом реалізації MATLAB / Simulink моделі отримано графічні залежності основних параметрів феромагнітного ротора за умов ступінчатої зміни обертового моменту та циклічної зміни кутової швидкості. За результатами моделювання помітно доцільність застосування методу непрямого керування з орієнтацією на поле для ефективного керування технологічним процесом двошнекового електромеханічного гідролізера. В порівнянні з розглянутими методами керування, непряме керування з орієнтацією на поле більш просте в проектуванні та реалізації, дозволяє досягнути бажаних характеристик та відкриває подальші можливості для дослідження двошнекового електромеханічного гідролізера

An Improved Direct Torque Control for a Single-Winding Bearingless Switched Reluctance Motor

The direct torque control (DTC) and direct force control (DFC) method were introduced to reduce the torque and levitation force ripple in single-winding bearingless switched reluctance motors (SWBSRMs). However, it still has some disadvantages. Firstly, the flux-linkage control is not suitable for the DTC method in SWBSRMs. On the one hand, it can increase the torque ripple. On the other hand, the RMS current can be increased and then the torque-ampere ratio is decreased. Secondly, the vectors selection is also unreasonable, which can increase the torque ripple further. In order to solve these problems, an improved control method based on DTC and DFC method for SWBSRMs is proposed in this paper, which can obtain high torque-ampere ratio and low torque ripple simultaneously. In the proposed method, the flux-linkage loop control is not needed and the space voltage vector table is improved. The experimental results show that the torque ripple is reduced by 66.7%, the torque-ampere ratio is increased by 200% and the switching times in one electrical period are reduced by 47.3%

A novel switching table for a modified three-level inverter-fed DTC drive with torque and flux ripple minimization

The use of a direct torque control (DTC) drive is a well-known control strategy that is applied frequently to induction motors. Although torque and stator flux ripples are major disadvantages of this approach, using a higher-level inverter helps to overcome these issues. In this paper, we propose a novel switching table with a modified control strategy for a three-level inverter to achieve ripple minimization, as well as smooth switching and neutral point balance; the latter features are generally ignored in many works. The proposed model is compared with a conventional DTC and an improved three-level inverter-fed voltage vector synthesis model in the Matlab/Simulink® environment with low, normal, and high-speed operation under load torque disturbances. The performance indexes and the comparative results confirm the effectiveness of the proposed model in reducing the torque and stator flux ripples by up to 70% and 78%, respectively, generating a lower total harmonic distortion (THD%) in all scenarios, in addition to maintaining the neutral point balance and preventing voltage jumps across the switches of the inverter

Torque Ripple Reduction of SRM Drive Using Improved Direct Torque Control with Sliding Mode Controller and Observer

The industrial application of the switched reluctance motor (SRM) is limited by its high torque ripples caused by the doubly salient structure. In this article, an improved direct torque control (DTC) with sliding mode controller and observer is developed to reduce the torque ripples of a four-phase SRM. First, a sliding mode controller based on a new reaching law is developed for designing a sliding mode speed controller (SMSC) for the DTC system. An antidisturbance sliding mode observer (ADSMO) is then proposed and combined with the SMSC to build a composite antidisturbance speed control strategy. Moreover, detailed simulation validations are carried out to reveal the effectiveness of the new reaching law, SMSC and ADSMO. Finally, experiments are conducted to verify the performance of the proposed SMSC-ADSMO in a DTC system with a four-phase SRM prototype

A new torque control approach for torque ripple minimisation in switched reluctance drives

The switched reluctance motor (SRM) has many merits, such as robustness, a simple construction, low cost, and no permanent magnets. However, its deployment in servo applications is restrained due to acoustic noise and torque ripple (TR). This paper presents a new torque control approach for TR reduction in switched reluctance drives. The approach is based on the maximum utilisation of the available dc-link voltage, hence extending the zero torque-ripple speed range. The approach is suitable for an SRM with any number of phases and stator/rotor poles. Soft switching control is deployed, which reduces switching losses. At any instant (regardless of the number of phases being conducted simultaneously), only one phase current is controlled. The well-established torque-sharing function concept is adapted and generalised to cater for more than two phases conducting simultaneously. MATLAB/Simulink confirmation simulations are based on the widely studied four-phase 8/6, 4 kW, 1500 rpm SRM.</p