METHOD FOR CONTROLLING SWITCHED RELUCTANCE MOTOR WITH STEPPED FREEWHEELING AND WITHOUT POSITION SENSOR

摘要

Provided is a method for controlling a switched reluctance motor with stepped freewheeling and without position sensor. The method is for a switched reluctance motor system employing a dual-switches-per-phase power converter. When both an upper transistor (S1) and a lower transistor (S2) of a main switch of a phase of the power converter are shut off, the phase enters a negative-voltage forced freewheeling state, and the current (i) of the phase is measured, either the lower transistor or the upper transistor of the phase is turned on when the current of the phase decreases to a predetermined threshold, the phase enters a zero-voltage natural freewheeling state, and the current of the phase starts to increase; when the current of the phase increases to a peak value, the position of a rotor is the minimal phase inductance leading-end position (b) and directly serves as a turn-on position of the main switch of the phase, and the upper transistor and the lower transistor of the main switch of the phase are turned on. The method obviates the need for additional hardware, obviates the need for a rotor position sensor, obviates the need for storing motor flux linkage data, is not limited in terms of control modes, has great real-time properties, great dynamic response performance, and great stability, and provides improved practicability and versatility.