抑制无刷直流电机电感效应的换相控制策略  

A Commutation Control Strategy to Suppress Inductance Effect on Brushless DC Motor

作　　者：郗珂庆 汪宸泽 刘云涛 XI Keqing;WANG Chenze;LIU Yuntao(Xi’an Aerospace Propulsion Testing Technology Research Institute,Xi’an 710025,China)

机构地区：[1]西安航天动力测控技术研究所,西安710025

出　　处：《微电机》2020年第5期85-90,共6页Micromotors

摘　　要：由于电感的存在,电感值较大的高速无刷直流电机换相时电流相位相对反电动势相位滞后明显,电流轴线偏离反电动势轴线严重。为改善此类电机的轴线偏移现象,文章提出一种改进的超前换相控制策略,通过保证两个轴线相互重合来提高电机的输出效率。该策略是在基于换相时间计算的基础上进行提前换相,并在换相过程中对三相电流同时进行PWM调制实现的。该策略没有将电机各参数做近似处理,对不同电阻、电感量级的电机均适用;采用使换相时间最小化的特定占空比,可实现电机效率的最大化。通过有限元仿真得到了在不同负载下应用本策略时的电流、转速和转矩波形图,将其与传统的换相方式作对比,比较二者的差异。仿真结果表明文章提出的换相控制策略在抑制轴线偏离方面效果明显,电机效率得到有效的提高。Due to the existence of inductance,when the high speed brushless DC motor with large inductance is commutating,not only the current phase lags behind the back EMF phase seriously,but also the current axis deviates from the back EMF axis seriously.In order to reduce the axis deviation of this kind of motor,an improved advanced commutation control strategy was proposed to improve the efficiency of the motor by ensuring that the two axes coincide with each other.This method impelled the motor to commutate in advance,based on the calculation of commutation time.Meanwhile,during commutation interval,the three-phase corporative modulation was used.This strategy did not approximate the parameters and was applicable to the control of motors with different resistance and inductance.The motor efficiency could be maximized by using a specific duty cycle,which could minimize commutation time.The waveforms of current,speed and torque were given under different loads in the simulation.The differences were analysed by comparing the waveforms of the proposed method and the conventional method.The simulation result shows that the proposed commutation control strategy is effective in restraining axis deviation and improving the motor efficiency.

关 键 词：无刷直流电机 电流滞后 轴线偏移 换相控制策略 

分 类 号：TM361[电气工程—电机] TP272[自动化与计算机技术—检测技术与自动化装置]