关键词: 无刷直流电机, 无磁链观测, 直接转矩控制, 转矩计算, 零电压矢量

Abstract: In view of the difficulty in torque calculations in the existing direct torque control of the brushless DC motors and the large torque ripples caused by the zero voltage vector defined by the traditional all-zero digital, further studies were made on the motor torque calculation and zero vector selections on the basis of the non-magnetic chain observation direct torque control systems. In the terms of torque calculations, the cumbersome back-electromotive force calculation method was abandoned, and the torque calculation was made combining three-phase current and Hall signals. In the terms of space voltage vector optimization, a two-tube conduction zero vector and space voltage selection table were proposed, and the control effectiveness was compared with the zero voltage vector defined by the traditional all-zero digital theoretically. The simulation model of the torque control systems was built in MATLAB/Simulink for simulation verification. A hardware experimental platform was set up using DSP2812 as the main control board for experimental verification. Both simulation analysis and experimental verification show that the proposed control method may further simplify the torque observation and effectively suppress the electromagnetic torque fluctuations in both of static and dynamic states.

Key words: brushless DC motor, non-magnetic chain observation, direct torque control, torque calculation, zero voltage vector