Three-dimension Finite Element Method Of Switched Reluctance Motor And Non-linear Study

Switched reluctance motor (SR motor) has become a strong competitor of DC motor and AC asynchronous motor, because switched reluctance motor has simple and firm structure, and wide speed-adjusting range, and excellent speed-adjusting performance and lower cost, but local saturation and severely non-linear character of two protruding-poles restrict some application field. The study of switched reluctance motor has mainly two aspects:magnetic field calculation of motor and speed controlling of motor. At present, magnetic field calculation adopts two-dimension finite element method (FEM) mainly, and the result of magnetic field calculation has much error because of ignoring two-terminal effect. It should adopt three-dimension finite element method. In switched reluctance drive, inductance and flux-linkage have severely non-linear character, so the research of non-linear character is also the key point.This paper is based on the research of the electromagnetism field of switched reluctance motor, and analyzes and calculates the electromagnetism field. Using two-dimension FEM and three-dimension FEM analyzes a 3kW, four-phase 8/6 switched reluctance prototype motor by ANSYS, and gets magnetic distribution and character curve of magnetic parameter, containing with curves of magnetization, and inductance character curves and torque character curves, which can provide theory basis for optimization of motor and the study for speed-adjusting system. According to the result of FEM and the math equation, the simulation models of switched reluctance motor non-linear speed-adjusting system can be founded. The character of system can be studied by an improved model of one-phase, and it is using angle position control for high speed and using current chopper control for low speed. The result of simulation shows that the controlling method of this system is reasonable and it can realize wide-range speed-adjustment. And it proved that the system has excellent start character and has excellent stability. So this paper validates the feasibility of FEM and validity of non-linear simulation models. The results of FEM of electromagnetic field and simulation of speed-adjusting system can use the extending study of switched reluctance motor, containing with the design and development of switched reluctance motor, and optimization of performance, and real-time control.