Accurate Measurement and Detailed Evaluation of Static Electromagnetic Characteristics of Switched Reluctance Machines

Abstract

Accurate static electromagnetic characteristics are essential basic data in the modeling of switched reluctance machine (SRM) for performance analysis and advanced control purposes. Because of the doubly salient structure and deep magnetic saturation, the electromagnetic characteristics of SRM have highly nonlinear relations with phase current and rotor position, which make the determination of these characteristics a difficult task. This paper proposes a digital signal processor-based method to accurately measure the flux-linkage and static torque characteristics of SRM. First, theoretical derivation and practical realization of the proposed method are presented in detail, and its accuracy is preliminarily verified by three ways: coenergy method, finite element method, and inductance-capacitance-resistance meter. Then, the errors in measurements are analyzed and corresponding methods to reduce them are given. Finally, with the improved neural network, the nonlinear simulation model of a SRM prototype is built in MATLAB with the measured characteristics, and the simulation results have good agreements with those from experiments, which further verify the accuracy of the proposed method.