Rotor-position Sensing System based on one type of Variable-reluctance Resolver

One new structure of variable reluctance (VR) resolver is presented to provide absolute rotor position signals for inverter-driven permanent-magnet synchronous motors. The new VR resolver is realized through varying rotor-pole shape in certain waveform, which can be determined through solving one inverse electromagnetic field problem. Samples are built and tests show that the position errors mainly comes from the odd-time harmonics and the null-voltage existing in the signals, and the precision of the sensors can meet the general requirements of motor driving