Rotor Position Detection of Synchronous Motor Based on High-frequency Signal Injection into the Rotor

In view of the existing problems of synchronous motor vector control system with mechanical sensor, sensor less motor control technology of synchronous motor is studied. A novel rotor position estimation method without mechanical sensor was suggested in this paper based on high-frequency signals injection into the rotor. With the structure of the synchronous motor itself as rotor position sensor, mathematical model for rotor position observer is established according to the principle of rotary transformer. The sensor less vector control model of synchronous motor is established based on the rotor high frequency signal injection. Simulation and experiment results show the reliability and a high level precision of the method.