基于级联式拓扑的消除无刷直流电机传导区转矩脉动方法

A Novel Method to Eliminate the Conduction Torque Ripple in BLDCM Using Cascade Topology Structure

在无刷直流电机的数学模型基础上,详细分析了传统的H_PWM-L_ON调制方式对BLDCM的非导通相引起续流电流的原因,以及由此续流电流导致非换相期间(传导区)的电磁转矩脉动的现象。通过原理分析及数学推导,提出在三相逆变桥入端加上前级直流变换器,利用单一直流母线电流的反馈闭环来控制电机的新策略。该方法在理论上彻底地消除了BLDCM在传导区内的转矩脉动,并且利用试验证明了此方法的有效性和可行性,说明比较适合用高精度要求下的无刷直流电机控制系统。

This paper presents a comprehensive research on torque ripples of brushless dc motor drive in conduction region based on the mathematical models.The phenomenon of torque ripples of conduction exists because of diode freewheeling happened under the conventional PWM schemes.Through theoretical and mathematical analysis, a new method for reducing the torque ripple in brushless dc motors with a single current sensor has been proposed by adding the DC-DC converter that regulates the amplitude of the current. So in such drives, torque ripples are theoretically eliminated in conduction region. Effectiveness and feasibility experiments.So it is preferable for the drive system of the proposed control method is verified by of high accuracy-controlling BLDCM.