Sensorless Speed Control of Salient Rotor PM Synchronous Motor Based on High Frequency Signal Injection and Kalman Filter

The paper presents an approach to sensorless speed control of salient rotor permanent magnet synchronous motor, based on a high frequency signal injection scheme improved by the use of Kalman filtering. The rotor position estimation error signal is extracted from both the d- and q-axis components of the high frequency current in the estimated rotor position reference frame. Then it is processed by a Kalman filter which yields position and speed estimates, based on a parameter independent mechanical model. The problem of carrier recovery is addressed and a simple hut effective solution is presented and analysed. Realistic simulations accounting for the inaccuracy of the digital implementation are presented and discussed.