A new sensorless vector control method for permanent magnet synchronous motor without velocity estimator

In this paper, a novel vector control method for permanent magnet synchronous motors is presented. In this method, the velocity estimation is completely removed and vector control is accomplished in a new coordinate system. In conventional vector control methods, the control effort is calculated in rotating coordinates with a synchronous speed of /spl omega//sub r/. However, in the proposed method, the control effort is calculated in rotating coordinates with reference speed /spl omega/*. This change of coordinate decreases the calculation effort significantly. In order to verify the applicability of the proposed control law, a Lyapunov-based stability condition is derived and the performance of the controller is verified through simulations and experiments. The obtained results illustrate the effectiveness of the proposed method despite the simplicity of its implementation.