Design of Sliding-Mode Speed Controller With Active Damping Control for Single-Inverter Dual-PMSM Drive Systems

In this article, a novel sliding mode speed controller is proposed for the parallel operation of dual permanent magnet synchronous motors (PMSMs) with a single inverter. For this operation, the vector control method is applied to the master motor drive and the open-loop control mode is employed for the slave one. If the load torques of two motors are different, oscillations in the speed of the slave motor will occur due to the difference in the rotor positions. Therefore, a damping control that can suppress these oscillations is required for the stable operation. The proposed controller consists of a speed controller for the master PMSM and a damping controller for the stable operation of two motors, designed based on sliding-mode control theory. With this nonlinear controller, robust control performance can be obtained for parameter mismatch of two motors. The feasibility of the proposed control scheme has been verified by simulation and experimental results.