An enhanced reliability method of initial angle detection on surface mounted permanent magnet synchronous motor

This paper proposes an improved voltage vector method of the rotor initial position angle detection on surface mounted permanent magnet synchronous motor (SPMSM) based on the analysis of inductance saturation effect. The accuracy of permanent magnet synchronous motor (PMSM) initial angle detection is the decisive factor in successful starting. To deal with the problems of low accuracy and unreliability in the traditional detection method of voltage vector, it uses reverse direction inductance to add constraints when the second series of voltage vectors are applied. And the actuation duration of voltage vector is extended to make current amplitude large enough for detection after the second series of voltage vectors. By enhancing the effect of strengthening or weakening magnetic field and enlarging the difference between each vector current, it finally improves the reliability of initial angle detection. The experimental results verify the feasibility and effectiveness of the analysis. It shows that the detection method can not only assure that the rotor is stationary, but also improve reliability greatly and increase the accuracy from 7.5° to 1.8° for initial position detection. So the method has great value in practical engineering.