Compensation of amplitude imbalance and imperfect quadrature in resolver signals for PMSM drives

This paper proposes a compensation algorithm to reduce position errors due to nonideal resolver signals in vector control drive system of permanent magnet synchronous motor (PMSM). Resolvers are commonly used to obtain an absolute rotor position information in severe environments. However, resolver generates periodic position errors because of amplitude imbalance and imperfect quadrature between resolver output signals. As a result, the d- and q-axis currents of the synchronous reference frame have ripples of twice the stator fundamental frequency in PMSM drives. In this paper, the compensation algorithm is proposed to reduce the position errors caused by the amplitude imbalance and imperfect quadrature, respectively. Moreover, this is implemented in the vector control drive system of PMSM. The proposed algorithm does not require any additional hardware and needs a few computation times to implement it. Experimental results verify the effectiveness of the proposed algorithm.