전류각제어에 의한 스위치드 릴럭턴스 전동기의 성능최적화

Abstract

The inherent simple construction, low manufacturing cost, low inertia, high speed, and fault tolerance of a SRM(Switched Reluctance Motor) makes it a strong candidate over other motors in variable speed drive applications. On the contrary, the higher torque ripple compared with conventional machines is the primary drawback the causes vibrations and acoustic noise. Additionally, the analysis of a SRM is quite cumbersome due to double saliency and the non-linearity introduced by the intense magnetic saturation of the corner of partially overlapping stator and rotor poles. Hence, the numerical methods are largely employed for analyzing and evaluating their performance. A high performance SRM drive is mainly characterized by torque ripple minimization and energy efficiency optimization. The average torque control is based on time-averaged analysis of machine operation and control is developed on per stroke basis. There is a need for an easily implemented and cost-effective control method that provides SRM drive performance over wide speed range. The optimal turn-off angle, commutation angle is defined at the critical rotor position that the flux-linkage of two neighboring phases are equal to half of the flux-linkage peak value. The mathematical description of the SRM is very complicated, hence SRM performance optimization can be analytically approached through motor running waveforms. Specifically, the overlapping region of the flux-linkage profiles of two neighboring phases that produce positive torque is considered. In this paper, the problem of performance optimization in current controlled SRM drives is investigated. and represent average torque control schemes for switched reluctance motors based on current control. For the purpose of finding the optimal switching commutation point or angle with proposed controller, It is utilized online turn on and turn off position calculation with voltage and current controller. The goal of proposed paper is the maximization of the energy conversion per stroke for maximizing efficiency and low torque dip control with approximately flat-topped current waveform. The proposed control scheme is on 8/6 SRM drives, four phases SRM drives demonstrated simulation results and on a prototype experimental system. The optimized performance can be reached with the correct balance of the energy efficiency and torque ripple criteria. The Proposed controller are very simple and easily implemented since the knowledge of the exact SRM model is not required. Finally, proposed system will respect to apply traction system, automobile, electric fan, pump and so on.