Performance Analysis and Control of Dual-stator Motor in Cooperative Robots

Due to its high efficiency and energy savings, permanent magnet synchronous motors are frequently utilized in the joints of cooperative robots. Most of these motors are single-stator motors. The predominant issues of the single-stator motor are low torque density and giant torque ripple, which result in inadequate load capability and chattering in the course of operation. This paper proposes a dual-stator motor with a 70 mm outer diameter to solve this problem. The physical model of the dual-stator motor is established for performance analysis and control simulation. The performance analysis of the dual-stator motor, which mainly focuses on the electromagnetic field, is conducted in Ansys Electronics. Simulation of magnetic field oriented control using mathematical model is conducted in Simulink. Under the conditions of 200 rpm (revolutions per minute) and 5 A effective current, the average torque of the motor reaches 4.74 N m, and the torque ripple is only 2.3%. The result proves that the proposed dual-stator motor has larger torque density and smaller torque ripple than the traditional single-stator motor with the same specification. The magnetic field oriented control is used when the motor tracks 200 rpm. The control simulation analysis shows that the overshoot is less than 1%, and the rise time is 0.015 s.