Optimized Power Factor Correction for High Speed Switched Reluctance Motor

The Power Factor Correction(PFC)in Switched Reluctance(SR)motor is discussed in this article.The SR motors are applicable for multiple applications like electric vehicles,wind mills,machineries etc.The doubly salient structure of SR motor causes the occurrence of torque ripples,which affects the power factor of the motor.To improve the power quality,the power factor has to be corrected and the ripples have to be minimized.In order to achieve these objectives,a novel power factor correction(PFC)method is proposed in this work.Here,the conventional Diode Bridge Rectifier(DBR)is replaced by a Bridgeless Hybrid Resonant(HR)converter,which assists in improvising the output in a wider range.The converter is chosen because of having variety of beneficial measures including high gain.The converter’s output is fed to the SR motor by means of an asymmetric Bridge Resonant(BR)converter.The proposed converter operates in continuous mode of conduction with the switching frequency of 10 KHz.A hysteresis current controller and Proportional Integral(PI)controller are utilized for reducing the harmonics in the source current along with the regulation of output voltage.In addition,the speed control of SR motor is accomplished by means of the Whale Optimization Algorithm(WOA)assisted PI controller.The proposed methodology is effective for the control of unity power factor,torque and current ripples.The Total Harmonic Distortion(THD)of the source current is also minimized,which suits the standard of International Electrotechnical Comission IEC 61000-3-2.By this methodology,the power factor of 0.99 is achieved with 97%efficiency and 3.92%THD.The proposed methodology is validated in simulation by MATLAB and in hardware by FPGA Spartan 6E.

An Analytic Method of Segmented PWM Duty Cycle for Switched Reluctance Motor

In view of the large current peak and torque ripple in the actual current chopping control of switched reluctance motor,a segmented PWM duty cycle analysis method of switched reluctance motor based on current chopping control is proposed in this paper.The method realizes the control of the winding current by adjusting the average voltage of the two ends of the winding in one cycle through the PWM duty cycle.At the same time,according to the inductance linear model,the conduction phase is divided into a small inductance region and an inductance rising region,and the analytical formulas of PWM duty cycle in the two regions are deduced respectively.Finally,through matlab/simulink simulation and motor platform experiment,the current chopping control is compared with the segmented PWM duty cycle analysis method in this paper.Simulation and experimental results show that the segmented PWM duty cycle analysis method can effectively reduce the current peak and torque ripple,and has high practical application value.

Research on Switched Reluctance Motor for Automobile Starter/Generator System

A self-designed and developed 12/10 switched reluctance motor(SRM)is chosen as the object of study and a prototype of 2.5?kW switched reluctance starter/generator with fly-wheel is designed based on the requirements of the selected engine (Changan Aotooc three-cylinder engine wagon) for the starter, generator and drive. The 36?V/42 V DC source system is applied to establishing the simulation-analyzing model of the motor. A finite-element (FE) analysis of its two-dimensional electromagnetic field is conducted to obtain the exact model of the motor. Systematic simulation is carried out combining with its power conversion circuit and control element. Meanwhile the starting process and performance of the system are studied and analyzed with special efforts. Satisfactory result is derived from the testing of the prototype: theoretical analysis is basically matched with the tested data, which proves the rationality and feasibility of the design procedures, systematic modeling and control strategies. Therefore, the new 12/10-structure scheme is put forward based on the development and analysis of various SRM and it meets the requirements of the researched motor in terms of the structural parameters.

Research of Reinforced Excitation Scheme for the Switched Reluctance Generator

This paper focuses on the reinforced excitation scheme for the switched reluctance generator (SRG) operating in a low voltage and wide speed range system. From the operational principle of SRG discussed, it can be seen that the key element to SRG generating is the reasonable and sufficient excitation. So the reinforced excitation scheme is addressed and proved by the tests of an SRG system.

RESEARCH OF THE SWITCHED RELUCTANCE STARTER/GENERATOR SYSTEMS

This paper focuses on the simulation and test of the switched reluctance starter/generator systems. Through the emulational analysis of the initial starting torque, the optimal turn-on section of the power switches is discovered. The fundamental theory of the generating operation is analyzed with the linearity model, and a new method is presented based on voltage pulse width modulation for the generating mode control. Through the steady-state and optimized emulation of the output power and system efficiency, the optimizational control approach for the generating mode over a wide speed range is introduced. At last, the test of the 3KW prototype system shows that the dynamic and static performance of this system is fine.

Optimal design of linear switched reluctance motor for sea wave power generation

The switchless reluctance motor’s non-permanent magnet structure design ensures its high reliability in the marine environment;thus,it is a feasible solution for the generator of a sea wave power generation system.However,the corresponding thrust density and efficiency remain insufficient.This study focused on a new type of flat linear switched reluctance motor(LSRM),using the finite element software to establish a structural model,and optimized the design with the goal of improving the efficiency and energy density.The entropy method was adopted for sensitivity stratification to objectively select weights to avoid the influence of subjectively selected different proportional weights on the optimization results.Based on the entropy method,the sensitivity of different structural parameters was stratified,and the simulated annealing algorithm,response surface method,and single parameter scanning method were combined for optimization.Finally,the optimal structural size parameters of the motor were determined.Based on the two-dimensional finite element method,to simulate the electromagnetic performance of the reluctance motor under different operating conditions,such as thrust,loss,and efficiency,changes in motor performance before and after optimization were compared to verify the high power generation efficiency and energy density of the optimized linear motor.

Voltage Control of a 12/8 Pole Switched Reluctance Generator Using Fuzzy Logic

This paper presents a voltage controller for a 12/8 switched reluctance generator (SRG). SR machines have a robust with simple structure because they have no windings or permanent magnets on the rotor, so they are capable of working at high speed application and at rough condition. However, due to nonlinear nature, doubly salient poles, time variant parameters, and non-ideal current waveform, The SRG output voltage inherently contains ripples. The proposed voltage controller is based on fuzzy logic that is very efficient over uncertainty and parameter variations. The effectiveness of the proposed control method is verified by comparing the obtained result with that of a PI-controller.

Switched Reluctance Generator for Variable Speed Wind Energy Applications

The aim of this paper is to analyze the potential of switched reluctance generator (SRG) in wind energy application. The machine comprises of switched reluctance generator, power converter and controller. In this paper the main ele-ments that form the generator system is discussed. It also highlights the common type of converter and structure used for SRG in wind energy application and types of control strategy available. Using power converter for switching the generator can operate over a wide speed range. Its applications in high speed area such as starter/generator for air-craft and gas turbine has been established, however the low/medium speed operation is still at an early stage of re-search. In order to subject the machine to various parameters, offline modeling is being investigated to produce the best optimum design.

Performance Prediction of Switched Reluctance Motor using Improved Generalized Regression Neural Networks for Design Optimization

Since practical mathematical model for the design optimization of switched reluctance motor(SRM)is difficult to derive because of the strong nonlinearity,precise prediction of electromagnetic characteristics is of great importance during the optimization procedure.In this paper,an improved generalized regression neural network(GRNN)optimized by fruit fly optimization algorithm(FOA)is proposed for the modeling of SRM that represent the relationship of torque ripple and efficiency with the optimization variables,stator pole arc,rotor pole arc and rotor yoke height.Finite element parametric analysis technology is used to obtain the sample data for GRNN training and verification.Comprehensive comparisons and analysis among back propagation neural network(BPNN),radial basis function neural network(RBFNN),extreme learning machine(ELM)and GRNN is made to test the effectiveness and superiority of FOA-GRNN.

Electromagnetic Design of a Switched Reluctance Motor With Segmental Rotors and Full-pitch Windings

整距绕组分块转子开关磁阻电机具有高速运行时低风（油）阻和低铁心损耗等优点，特别适合用于航天航空驱动系统。根据整距绕组分块转子开关磁阻电机的基本工作原理，结合输出功率与平均转矩的关系，将绕组电流等效为方波，推导出了整距绕组分块转子开关磁阻电机的主体尺寸计算公式；基于电机定转子未对齐位置和对齐位置的电磁特性，以及整距绕组分块转子开关磁阻电机的电磁特点，确定了定、转子极弧系数选取的规则；同时分析了绕组匝数等主要尺寸的选取的规则；最后，基于上述方法优化设计了一台实验样机，并通过有限元仿真及实验验证了整距绕组分块转子开关磁阻电机的电磁设计方法的正确性。

State of the Art of Switched Reluctance Generator

This paper provides a comprehensive review of the recent development on the switched reluctance machine operating in generating mode in both the low and high speed operations. The machine consists of a salient rotor and stator poles and controlled via switching of the power electronic devices. There is a steady development of the machine operating in the motoring mode;however, its generating operation is still under study. This paper gives an overview of the machine, followed by the principle of operation in generating mode and briefly discusses the structure and types of control methods which involve the switched reluctance generator (SRG). Due to its geometry simplicity and advantages such as robust, ability to operate over a wide speed range and absence of permanent magnet and windings on the rotor, the SRG promises to be a good candidate for variable speed application.

Design and Initial Testing of An Integrated Switched Reluctance Starter/Generator System for Unmanned Aerial Vehicle

According to specific performance requirements,an integrated switched reluctance starter/generator system,which can start the engine and supply electrical energy to the loads,is designed and manufactured for the unmanned aerial vehicle.Considering the required starting torque and speed range,the geometrical dimensions of the switched reluctance machine are calculated based on the output equation and further optimized with finite element analysis,and the flux-linkage,inductance and static torque characteristics are illustrated.To verify the performances of the designed system,detailed simulation with the model considering piston engine and experiment using the test bench are carried out.

An Integrated Wind and Hydro Power System Using Switched Reluctance Generator

This research work seeks to make renewable energy more reliable, cost effective, and accessible by exploring a different energy combination system to that currently applied to wind and hydro power. Instead of the usual electrical combination of wind and hydro generators, this work involved combining a water and wind turbine mechanically, before driving an electrical generator. This new combination system was modeled and optimized in MATLAB, using a direct combination system commonly found in multi-engine helicopters. The system was found to operate satisfactorily, however it is mechanically more complex than current electrical combining systems. Research was undertaken regarding wind and water resource availability, and the turbines were chosen with these taken into consideration. Various combination systems were explored, including torque and speed split mechanical combinations, conventional electrical combination, and using a modified switched reluctance generator as a method of electro-mechanical combination. The generator selected for this work is a three phase 12/8 Switched Reluctance (SR) machine. A detailed winding polarity having four poles per phase and their effect on the performance of the machine is

Optimal Output Power Control of Switched Reluctance Generator at a Constant Speed

In order to control the output power of a switched reluctance generator(SRG)at a constant speed,the output power of SRG is theoretically analyzed by using freewheeling control.First,through a theoretical analysis,a finite element simulation and an experiment,it was verified that the output power of SRG cannot be improved by using freewheeling control with a single pulse control method(SPCM).Then,the maximum output power can be obtained by optimizing the turn off angles of SPCM at a constant speed,and at the same time,the formula of the optimal turn-off angle was presented,which meets the criterion for the output power maximization.Finally,numerical simulation and experimental results demonstrated the validity of the theoretical analysis.

A CONTROL STRATEGY OF SWITCHED RELUCTANCE MOTOR FOR ELECTRIC VEHICLE APPLICATION

A control strategy of switched reluctance motor (SRM)for electric vehicle applications is proposed. In electric vehicle application, the switched reluctance motor is a good choice with its flexible control method, compactness, robustness, high efficiency and high starting torque. In this paper, the control strategy of motoring and regenerative braking for electric vehicle application is presented. Computer simulations are employed to analyze the steady state behavior of SRM propulsion system. Experimental results in electric motorcycle are provided to demonstrate the validity of SRM propulsion system.

High Frequency Charging Techniques—Grid Connected Power Generation Using Switched Reluctance Generator

Power generation becomes the need of developed, developing and under developed countries to meet their increasing power requirements. When affordability increases their requirement of power increases, this happens when increased per capita consumption. The existing power scenario states that highest power is produced using firing of coals called thermal energy. A high efficiency Switched Reluctance Generator (SRG) based high frequency switching scheme to enhance the output for grid connectivity is designed, fabricated and evaluated. This proposed method generates the output for the low wind speed. It provides output at low speed because of multi-level DC-DC converter and storage system. It is an efficient solution for low wind power generation. The real time readings and results are discussed.

Analysis and Control of a Three-Phase Switched Reluctance Wind Generator

This paper deals with various aspects of modeling, simulation, analysis, and control ofa SRG （switched reluctance generator） in different modes of operation. Excitation method of such a generator is shortly described. The output power of the SRG is controlled so that it can track the maximum output power of a wind turbine drive applications. Also, the output generator voltage is stabilized under either load or wind speed variations. Basic operational characteristics of a three-phase 6/4 SRG are developed through experimental observation. Meanwhile, the real-time operation was implemented in a DSP （digital signal processor） environment. The simulation of the complete system model has been obtained using the Matlab/Simulink software. A good agreement between experimental and simulation results has been observed which supports the validity of the proposed analysis.

Accurate Torque Modeling With PSO-Based Recursive Robust LSSVR for a Segmented-Rotor Switched Reluctance Motor

In order to improve the reliability in torque calculation of SRM,an accurate nonlinear torque model regresses by recursive robust least squares support vector regression(RR-LSSVR)is proposed in this paper.The model is in terms of a segmented-rotor switched reluctance motor(SSRM).The characteristics of the SSRM is introduced to show its nonlinear characteristics both in magnetic and torque.Then,its mathematic model is established,and an accurate inductance measurement method and a torque calculation method are presented.After this,the principle of the RR-LSSVR and why it can adjust weights according to errors are described.The model used the RR-LSSVR algorithm shows an outstanding capability in accuracy and quickness compared with other algorithms.Finally,to further validate the accuracy of the proposed model in practical application,simulation and experiment are designed based on a 16/10 SSRM.

Design andtwo-objective simultaneous optimization of torque controller for switched reluctance motor in electric vehicle

In order to reduce the torque ripple,increase the average torque and optimize the drive performance of the switched reluctance motor (SRM),the nonlinear dynamic model of SRM is established in the MATLAB /Simulink environment.The effects of the turn-on and turn-off angles are investigated by the simulation results of the dynamic model,and the function is made among the rotor speed,turn-on angle and turn-off angle.To optimize the torque dynamic performance,the two-objective simultaneous optimization function is proposed by two weight factors.And the optimized turn-on and turn-off angles as functions of rotor speed are developed by using the simultaneous optimization method.Then the optimized torque controller is designed based on the optimized turn-on and turn-off angles.The simulation results show that the optimized torque controller designed in this paper can effectively reduce the torque ripple and increase the average torque,and optimize the torque dynamic performance of the SRM.

Winding Inductance and Performance Prediction of a Switched Reluctance Motor with an Exterior-rotor Considering the Magnetic Saturation

This paper deals with an analytical method to effectively calculate the inductance of an exterior-rotor switched reluctance motor(SRM),which evaluates the winding inductance of both the active section and the end section,accounting for the influence of core saturation.According to the inductance calculated by the analytical model,the flux linkage table and torque table can be established,and the steady state performance such as phase current,flux linkage,copper loss and core loss can be predicted.Effectiveness of this method is verified by the finite element method as well as by experimental results of a 12/8 SRM prototype.