One SPMSM Speed Vector Control System Design Method Based on the Incremental Encoder

Aimed at the rotor angle information problem used for the surface-mounted permanent magnet synchronous motor (SPMSM) speed control system by vector control method, one rotor angle information gaining method based on the incremental encoder is given. The relationship between the constant voltage vector and the torque is analyzed. The zeroposition signal can be gained by applying the different voltage vectors in sequence to make the rotor rotate. On the basis of gaining the zero-position signal, the rotor angle information used for the SPMSM speed control is computed by the number of pole pairs and the pulse number outputted by the incremental encoder. The above method is used in SPMSM speed control system. And the experiment result shows that this method can achieve the precise speed control purpose.