THE VIRTUAL OPTICAL ENCODER TECHNIQUE IN AC MOTORS
Qiu Dong-yuan · Proceedings of the CSEE · 2005
Combining the phase-locked loop (PLL) theory with the dynamic model of ac motor, the rotor information (such as velocity and position) are identified from the sensed phase voltage and phase current, and then transferred to three channels (A, B and Z) digital pulses which are similar to the output signals of incremental optical encoder. The virtual optical encoder is realized by software. A permanent magnet synchronous motor (PMSM) is used as an example in this paper. The experimental results prove the feasibility of the proposed technique.