Method and apparatus for sensing the rotor position of a switched reluctance motor without a shaft position sensor

摘要

Apparatus and method for detecting rotor (12) position in a switched reluctance motor (18) having multiple stator phases (A-A', B-B', and C-C'). A multiplexer (48) intermittently connects a known resistor (54) to a non-conducting stator phase. Circuitry (62 and 68) detects the amplitude of the current passing through the resistor (54) and the phase difference between the varying voltage and the current passing through resistor (54). The resulting signal is proportional to the position of rotor (12).