关键词: 无刷直流电动机, 转矩下降, 提前换相, 低转矩波动, 动态调整

Abstract:

The torque ripple limits the application of brushless DC motors in high precision and stability system. Some problems come out, such as the increasing torque ripple and the descending output torque descending can be caused by high rotated speed. With the analysis of torque ripple in the process of advanced commutation according to the equivalent model, a simple advanced commutation PWM modulation scheme was proposed. This controlling scheme made the current point of intersection ahead to the BEMF’s and leads the angle dynamically adjusted with the changing motor running state. A control method process was provided and the MATLAB/Simulink simulation module was built. The simulation results verified the effect of the controlling method that can suppress torque ripple and descending output torque.

Key words: brushless DC motor, output torque descending, advanced commutation, low torque ripple, adjust dynamically