On Delta-Sigma-Modulation techniques for Permanent-Magnet Synchronous Motors

Due to the availability of efficient three-phase inverters, Permanent Magnet Synchronous Motors (PMSM) have become an interesting drive concept for numerous applications. However, for efficient and smooth operation, the inverter input switching signals have to be modulated in a suitable way in order to obtain an appropriate commutation sequence for operating a PMSM. Besides of the well-known and commonly applied Pulse-Width-Modulation (PWM) techniques, Delta-Modulation and Delta-Sigma-Modulation (DSM) techniques have been proposed in literature for driving inverters. This paper investigates the suitability of such DSM techniques for modulating two-stage and three-stage inverters for PMSM applications.