一种等效微分环节反馈滤波电容电压实现有源阻尼的方法

Method of achieving active damping by filter capacitor voltage feedback with equivalent differential link

常规的微分实现方法在直接用于反馈滤波电容电压实现有源阻尼时易放大高频噪声,影响进网电流质量以及阻尼效果。为此,提出采用负带通滤波器串联滞后校正环节来实现等效微分环节。该方法在用于反馈滤波电容电压实现有源阻尼时,不仅能够有效地抑制LCL滤波器的谐振尖峰,还对高频噪声具有抑制作用。所提策略解决了常规微分实现方法反馈LCL滤波器状态量实现有源阻尼放大高频噪声的问题。通过搭建一台实验样机,验证了所提策略的有效性。

When the conventional differential implementation method is directly used to feedback the filter capacitor voltage to achieve active damping,it is easy to amplify high-frequency noise,and affect the quality of the grid-in current and the damping effect.Therefore,adopting the negative band-pass filter in series with the lag correction link to achieve the equivalent differential link is proposed.The method can not only effectively suppress the resonance peak of the LCL filter,but also suppress the high-frequency noise when it is applied to feedback the filter capacitor voltage to achieve active damping.The proposed strategy solves the problem of amplifying the high-frequency noise by the conventional differential implementation method on feedback LCL filter status.The effectiveness of the proposed strategy is verified by building an experimental prototype.