无刷直流电机反电势过零点检测转子位置研究

Research on the Detection of BLDCM Rotor Position by Checking Zero-crossing of Back-EMF

电动车无刷直流电动机无位置传感器控制技术是近年来的一个研究热点。从理论上对反电势法检测转子位置进行了研究,提出了在PWM"ON"时刻检测反电势过零点信息的方案,并给出了具体的软硬件实现方法。试验结果表明,该方案可较好地实现无刷直流电机转子位置的检测和电流换相控制,工作稳定可靠,具有一定的实用价值。

Position sensorless control is often required in brushless DC motor （BLDCM） when electric bikes run without position sensors.After in-depth research on the ＂Back-EMF＂ method theoretically,this paper proposes a solution based on checking the zero-crossing of the back electromotive force （Back-EMF） during PW ＂ON＂ period.A practical implementation of this solution in both software and hardware is given.The experimental results show that the solution provided not only precise detection of the rotor position and better control of current commutation, but also practical value for its stability and reliability in use.