Performance Of Switched Reluctance Machine Research Articles

Performance Investigation of Switched Reluctance Motor Driven by Quasi-Z-Source Integrated Multiport Converter with Different Switching Algorithms

Switched reluctance machines (SRMs) have received increasing attention for their many potential uses, such as for wind power and electric vehicle (EV) drive systems. The Quasi-Z-source Integrated Multiport Converter (QZIMPC) was recently introduced to improve the reliability of the SRM driver through small capacitance values. It is not possible, however, to simultaneously energize and deenergize two SRM phases in QZIMPC. This phenomenon can significantly increase the commutation period which, in turn, degrades the performance of SRM; in addition, this causes high-voltage ripples on the converter’s capacitors. Two switching algorithms are introduced and applied in this paper, and their performance with SRM is investigated in terms of torque ripple and peak phase current. The algorithms are based on prioritizing the control command in the on-going and off-going phases to fulfill the required load torque, as well as to accelerate the commutation process where possible. This is achieved without the interference of high-level controllers, which include speed controllers and/or torque ripple minimization. Through the simulation results, a comparison between the two switching algorithms is presented to determine their potential to improve the SRM drive system’s performance.

Structural Analysis of Induction Machine and Switched Reluctance Machine

Here we present a comprehensive analysis of structural performance of Induction Machine (IM) and Switched Reluctance Machine (SRM) rotors under different operational conditions. Electric machines are susceptible to forces of diverse origins. In addition to traditionally considered magnetic and centrifugal forces, this article discusses independent and inclusive effects of thermal expansion and shaft attachment techniques on structural integrity of the machines. A comparative analysis of structural performance of IMs and SRMs has also been performed, under a range of scenarios, to facilitate application-specific machine selection from a structural perspective.

Adaptive Feedforward Control Applied in Switched Reluctance Machines Drive Speed Control in Fault Situations

Many industrial and laboratory applications which make use of electric machines require noninterruption operation, even in the presence of faults, such as power generation and electric vehicles. Under fault scenarios, the performance of the system is expected to degrade and control techniques may be helpful to overcome this issue. Within this context, phase faults are obviously undesired, as may lead the machine to stop operating. Switched reluctance machines (SRM), due to its inherit characteristics, are naturally tolerant to phase faults, despite the loss of performance. Most of the techniques used to improve the performance of SRMs in fault situations are related to the switching feed converter. Regarding this issue, instead of presenting an alternative converter topology, this work alternatively proposes a control approach which significantly reduces the phase faults effects on the speed of the motor. Furthermore, the high-frequency noise is attenuated when compared to the classical proportional–integral (PI) controller, commonly applied to control such sort of motors. The proposed SRM-adaptive feedforward control (AFC) controller is able to recover the speed of operation faster than a classical approach, when a feedforward action is not taken into account.

A New Decoupled Analytical Modeling Method for Switched Reluctance Machine

This paper proposes a new decoupled analytical modeling method for switched reluctance machine (SRM). The flux linkage is represented by a second-order Fourier series, and the coefficients of the series are position dependent, which can be further expressed by another second-order Fourier series. The proposed method only needs 21 data points from five rotor positions. Then, the static torque characteristics are analytically obtained based on the expression of the flux linkage. The accuracy of the method is verified by comparing the calculated flux-linkage and static torque characteristics with those from measurements. With the calculated flux-linkage and static torque data, the dynamic performance of SRM is simulated under both motoring and generating mode. The simulation results, such as phase current and mechanical characteristics, agree well with those from the experiment, which further proves the effectiveness of the proposed method.

Modular switched reluctance machine with E-core stators and segmental rotors for high reliability applications

In this paper a novel modular switched reluctance machine (SRM) with E-core stators and segmental rotors is presented. Unlike the conventional SRMs, there are hybrid radial and axial magnetic paths in the E-core stators due to the particular construction. An approximate and simplified 2D finite-element analysis (FEA) model is proposed to calculate its magnetic characteristics and compared with 3D FEA model results. A comparison of the static magnetic characteristic and dynamic performance between the modular SRM and a conventional SRM is made to emphasize the superiority of this novel SRM. Furthermore, the fault tolerant performance of this modular SRM under open-circuit faults is also presented. Finally, a prototype machine is built and tested in the laboratory. The flux linkage characteristics are experimentally obtained by indirect method and are compared with FEA results. Other experimental results such as single-pulse operation, closed-loop control operation, fault-tolerant operation at open-circuits and sudden change in load torque operation are also presented to validate the analytical and simulation results of the modular SRM and its performance.

Control Performance Analysis of SR S/G System Based on FEM

Switched reluctance machine (SRM) has many outstanding advantages, and can be widely used in many electromechanical applications. However, it’s relatively difficult to analyze the control performance of SRM due to strong nonlinearity of the electromagnetic field. In this paper, the performance of SRM is analyzed by finite element method (FEM). Firstly, the simulation model of a 4-phase 8/6 pole SRM is built, and then the steady-state and dynamic simulation are carried out. In steady-state simulation, the magnetization and torque characteristics are obtained by parametric method. In dynamic simulation, the performance, include current and torque curve, under both motoring and generating mode are given. The simulation and analysis results are useful for performance optimization of SRM.

SRM Power Converter for Operation With High Demagnetization Voltage

Torque output of switched reluctance machines (SRMs) can be increased by operating with high demagnetization voltage, especially for high speeds. This is first illustrated using computed results obtained from dynamic simulation. A power converter with the capability of providing increased demagnetization voltage is then presented. The converter operation is analyzed, ratings of various components are derived, and a controller for regulating the additional demagnetization voltage is designed. Experimental results illustrate expected operation of the converter, and improved performance of the overall SRM drive in terms of increased torque and power output.