Comparative Study of Q-PLL and DSOGI with SMO Based Sensorless Control of PMSM Drive

This paper presents the comparative analysis of two different methods of Phased locked loop (PLL) with Sliding Mode Observer (SMO) for position estimation in a Permanent Magnet Synchronous Motor (PMSM) drive. The objective of PLL is to improve the position estimation in drive and the conventional Quadrature PLL (QPLL) unable to track accurate position and shows double frequency oscillations. In order to overcome this, and to remove the harmonics, Dual second order generalized integrator (DSOGI) is proposed with SMO and its performance is analyzed and compared with conventional QPLL at various speed and torque operating conditions. Simulation results shows the better harmonics rejection capability of DSOGI.