Patent ID: 7301333

Claim:
An angle position detection apparatus, for detecting the rotor position of a PM motor, comprising: a plurality of incorporated VR resolvers for changing reluctance in synchronization with the rotation of a rotary shaft; a resolver rotor fixed to the rotary shaft; a resolver stator opposite to the resolver rotor in a radial direction; stator poles protruding in a plurality of radial direction; a stator coil being supplied with an excitation signal and outputting an output signal; a transmitter for outputting an excitation signal; a switching unit for changing a supply path for the excitation signal so that the excitation signal output by the transmitter is transmitted to one of the alternately selected VR resolvers; and a detector for detecting an angle position for the rotary shaft based on a signal output by the VR resolver, wherein only one of the VR resolvers selected by the switching unit is excited, wherein the VR resolvers includes a first resolver and a second resolver, the first resolver includes the same number of polar teeth as that of the PM motor, and the second resolver is a high resolution position detection resolver.