PMSM's new sensor-less control with PLL for parallel drive

Abstract

The permanent magnet synchronous motor is a highly efficient motor because the loss such as copper loss and iron loss is about half that of the induction motor. For this reason, it is used in various scenes such as electric vehicles, hybrid vehicles, electric railway vehicles, and industrial machinery. However, since PMSM requires synchronous rotation speed information, a sensor is required, and a separate inverter is required for each motor. The authors have already proposed a new control method in which two units are driven in parallel using one inverter. This method used load angle estimation and V/F control, not vector control. Therefore, there was a problem that the control performance did not improve. In order to solve this problem, this paper aims to replace it with vector control and proposes sensor-less vector control using a new PLL. Since the proposed system is driven in parallel with one inverter, it is characterized by vector control by a coordinate system based on the inverter voltage. In this paper, we first verify the actual machine by driving it alone, and report that we obtained good results.