摘要
提出了基于虚拟中性点的转子位置检测策略,以实现无刷直流电机的无位置传感器控制。通过三个阻值相同的电阻引入三相端电压,将这三个电阻星形连接构造虚拟中性点,分析了无刷直流电机虚拟中性点电压与换相时刻的对应关系,得出虚拟中性点电压通过直流母线中点的时刻即为反电动势过零时刻的结论,并进一步分析了电机运行中,各个状态下,反电动势过零信号的有效性问题。通过实验进一步验证了这一方案,以比较器实现了过零信号的输出。相比于常规的端电压检测方法,系统减少了两路比较检测电路,并且无相移。实验表明,采用这种策略可以准确地确定过零信号的位置,同时避免了传统反电动势法在检测过程中带来的相位误差。
A rotor position detection strategy based on virtual neutral point was proposed to realize position sensorless control of BLDC motor.Through the three-phase terminal voltage with the same value of three resistances star connection to construct a virtual neutral point,the relationship between the virtual neutral point voltage and commutation time of BLDC motor was analyzed.A conclusion was drawed that the moment when the virtual neutral point voltage through the DC bus midpoint is the zero-crossing time of the back electromotive force(BEMF),and the operation of the motor in each state,the effectiveness of zero-crossing signal of BEMF was further analyzed.The scheme was further verified by experiments,and the output of zero-crossing signal was realized by comparator.Compared with the conventional terminal voltage detection method,the system reduced two comparison detection circuits and has no phase shift.Experimental results show that the position of zero-crossing signal can be accurately determined by using this strategy,and the phase error caused by traditional BEMF method can be avoided.
作者
万筱剑
万子博
WAN Xiaojian;WAN Zibo(Shenzhen Vishan Technology Co.,Ltd.,Shenzhen 518108,Guangdong,China;School of Electrical and Electronic Engineering,Harbin University of Science and Technology,Harbin 150006,Heilongjiang,China)
出处
《电气传动》
2024年第8期4-9,共6页
Electric Drive
