Improvement Torque ripple characteristics of Dual-Winding Square wave Brushless DC Motor with phase difference drive

Dual winding machine is known as having fault tolerant characteristics, so it is got much attention especially for application which needs failure tolerance like aircraft including Electro Mechanic Actuators (EMAs). Controlling each winding by independent inverters leads not only fault tolerance but also improvement drive characteristics, so it is widely considered nowadays. Moreover, Square Wave Excitation BLDCM is more simple control method than FOC, so it makes EMAs reliability increase. In this paper, we use 2 inverters controlled by 1 microcontroller for driving 10poles-12slots dual winding PMSM, operate the motor with current phase difference under square-wave excitation. Then we examine improving the BLDCM torque characteristics experimentally.Finally, it is confirmed that dual-winding BLDCM used in this paper with driving by 2 inverters found that it is possible to reduce torque ripple by current phase differential drive. In this test motor, it is found that the torque ripple and RMS current can reduce by exciting current having 30degree lead of phase difference to the motor.