电流型两象限斩波器控制无刷直流电动机的制动原理分析

Study on Brake Operation for Brushless DC Motor Based on Control of Two Quadrant Current Chopper

采用电流型两象限斩波器控制是稀土永磁无刷直流电动机减小电枢电流脉动的一个重要措施。虽然该系统在许多方面可采用一般无刷直流电动机的控制方法，但在制动控制上若仍沿用常规控制方法，将造成电机电流失控现象，损坏逆变器。本文对这种电流失控现象的机理进行了详细的分析，并在此基础上提出了有效的解决方法。最后对采用降压型斩波器和电流型两象限斩波器控制的无刷直流电动机的制动性能作了仿真比较，并对电流型两象限斩波器控制的稀土永磁无刷直流电动机进行了系统实验。数字仿真与系统实验表明，该电流型两象限斩波器控制的稀土永磁无刷直流电动机能可靠。

In order to decrease the current ripple of the rare earth permanent magnetic brushless DC motor, a two quadrant current chopper is used to control the voltage and current of the motor. If the conventional control method of brake is applied, the motor current will be out of control, which will result in failing in brake operation and damaging the inverter. The principles of the brake failure are analyzed and an effective measure is developed. Digital simulations are carried out to compare the brake performances between a brushless DC motor based on the two quadrant current chopper and that based on Buck chopper. The system experiment is done to investigate the dynamic response of the motor. The results of digital simulation and system experiment confirm that the system based on the two quadrant current chopper has attractive performances in the brake operation.