LCL型有源滤波器混合状态反馈虚拟阻尼控制策略

LCL Active Power Filter Based on Hybird States Feedback Virtual Damping Control Strategy

有源滤波器载波调制产生的高次谐波可通过L或者LCL滤波器滤除。LCL滤波器为三阶系统,高频谐波抑制性能优于L滤波器,但LCL型滤波器会产生谐振峰。提出一种混合状态反馈虚拟阻尼控制策略,能够在不增加有源滤波器电流传感器的情况下,实现有源阻尼控制,起到抑制谐振峰的效果。在实现虚拟阻尼控制策略的基础上,采用相位超前补偿的二阶广义积分器实现非线性负载谐波电流的无静差补偿控制,并通过公共耦合点电流反馈控制策略,实现有源滤波器基波与谐波的独立控制,提高了系统的响应速度与控制精度。最后通过样机实验验证了方法的有效性。

The harmonics generated by the active power filter carrier modulation are filtered by the L filter or the LCL filter. LCL filter is the third-order system, its high frequency harmonics suppression performance is better than the L filter, but the LCL filter will produce resonance peak. A virtual damping control strategy based on hybird states feedback is proposed to realize the virtual damping control and restrain the resonance peak without increasing the current sensor. On the basis of the realization of the virtual damping control strategy, this paper adopts the second-order generalized integrator with phase advance compensation to realize the current control of non-linear load harmonic without static error. The point of common coupling(PCC) current feedback control strategy makes the SAPF fundamental and harmonics current control independently, which improves the system’s response and control accuracy. Finally, the method is proved to be valid by the experiment results.