【摘要】 分析了无刷直流电机数学模型,对无刷直流电机无传感器控制的三段式起动与反电动势过零点换相技术做出研究。利用电机三相端电压与反电动势间关系来确定电机反电动势过零点与换相点,提出了基于三相反电动势的改进型反电动势过零点换相方法。设计了基于DSP_F2812的无刷直流电机控制平台。通过实验验证表明,基于三段式起动与改进型反电动势过零点换相方法的BLDCM无位置传感器控制达到了带霍尔传感器换相控制的精度与效果。更多还原

【Abstract】 A mathematical model of the permanent magnet brushless DC motor has been analyzed while three-step starting technology and commutation has been studied in this paper. Then an improvement method of back EMF zero-crossing detection base on the mathematical model of BLDC motor has been proposed. Commutating was guided by using the corresponding relation between motor ’ s terminal voltages and back EMF. A hardware system based on DSP_F2812 had been put up. Experimental result verify the reliability and utility of the sensorless control system by using three-step starting technology and back EMF zero-crossing detecting commutation comparison with HALL-sensor control.更多还原