无电解电容永磁同步电机驱动系统网侧电流谐波抑制策略

Input current harmonics suppression strategy for electrolytic capacitor-less IPMSM drive system

电机驱动系统的母线使用大电解电容会降低寿命和可靠性,使用小容值薄膜电容来替代大电解电容,可以提高系统可靠性,除去功率因数纠正(PFC)电路以降低成本,但要求在网侧具有高功率因数以及足够低的电流谐波,因此需要准确地控制逆变器输出功率以实现这种诉求。提出一种修正指令电流的方法控制逆变器输出功率。选择PIR控制器,以无静差跟随两倍工频波动的理想输出功率。另外,针对电流环响应频率以上的噪声,通过电压前馈的方式补偿,能够弥补电流环响应频率的不足。通过仿真以及实验验证有效性,使网侧功率因数达到0.9888,网侧电流谐波畸变率0.1489,网侧电流各次谐波均控制在EN 61000-3-2标准以下。

DC-link electrolytic capacitor critically reduces the life span and reliability of the motor drive system.Replacing the DC-link electrolytic capacitor with a small film capacitor improves the reliability of the system,as well as removes power factor correction(PFC)circuits to save costs.Hence the inverter power should be controlled to achieve high input power factor and low grid current harmonics.This paper proposes an inverter power control strategy based on modifying the instruction current.The inverter power controller is based on PIR controller in order to track the ideal output power which fluctuates at double of the source frequency.In addition,the response frequency of the current loop was limited,and voltage feedforward was used to compensate the high frequency noise.The effectiveness of the proposed methods was verified through simulation and experiments.The input power factor increases to 0.9888,the thd of input current decreases to 0.1489 and the input current harmonics satisfy EN 61000-3-2.