Switched reluctance motor position by resonant signal injection.

摘要

Apparatus for estimating the position of a rotor 17 of a commutated brushless motor 15 operating without a shaft position sensor includes a tank circuit (59a to d) that incorporates a phase winding of the motor. A low-power signal of a frequency F1, much greater than the switching frequency Fs of the phase winding, is injected into the tank circuit. By using variation of the characteristic resonant frequency F0 of the tank circuit, a detection circuit (16a to d) resolves the mechanical angle theta of the rotor and, thereby, controls the timing of the phase firing sequence.