一种不需要电容电流传感器的LCL滤波电路有源阻尼控制方法

An Active Damping Control Method for LCL Filter Circuit with no Need of Capacitor Current Sensor

针对LCL滤波电路中电力电子变流器的谐振问题,提出了一种反馈虚拟电容电流的有源阻尼控制方法。根据LCL滤波电路的拓扑结构,建立系统状态方程,再结合网侧电压推导出电容基波电流的幅值和相位,将产生的虚拟电容电流反馈到控制环,从而实现电力电子变流器LCL滤波拓扑的有源阻尼控制,抑制系统振荡,提高系统的稳定度。通过500kW光伏发电系统实验验证了这一控制方法的有效性。

In view of the resonance of power electronic converters with LCL filter circuit,proposed an active damping control method for virtual feedback capacitance current.The system state equation was created depending on the topology of LCL filter circuit,and then,amplitude value and phase of fundamental current of the capacitor were derived in combination with the voltage at the side of the network,thus the created virtual capacitor current would feed back to the control loop,thereby LCL filter topology of the power electronic converter could achieve active damping control,suppression of system disturbance,and improvement of system stability.By the experiment in 500 kW PV generating system it demonstrated the validity of this control method.