微电网并网系统中谐波传播抑制策略

摘要

在微电网并网系统中,对于公共耦合点(PCC)处谐波电压源而言,传输线路上电感与电容之间的谐振可能造成严重的谐波传播放大问题.为抑制该系统中的谐波传播放大,通过分析谐波传播规律,提出一种分频调节阻性有源电力滤波器(RAPF)的位置选择新策略.分析不同传输线长度时分频调节RAPF的电导增益取值对谐波抑制效果的影响,确定了电导增益的取值要求.通过合理选择电导增益,该位置选择策略可在任意传输线长度下有效抑制谐波传播放大.仿真和实验结果均验证了所提策略的正确性和有效性.%For the harmonic voltage sources on the point of common coupling(PCC)of a grid-connected microgrid,the series and parallel resonances between line inductance and capacitance may cause the serious harmonic propagation amplification.In order to damp out harmonic propagation amplification in the system,this paper proposes a novel site selection strategy of discrete frequency tuning resistive active power filter(RAPF)according to the harmonic propagation law.On the basis of the site selection strategy,the conductance gain of the discrete frequency tuning RAPF is limited with the variation of transmission line length due to its influence on the harmonic suppression performance.However long the transmission line is,the proposed site selection strategy could suppress the harmonic propagation amplification effectively by choosing the conductance gain reasonably.Simulation and experimental results validate the effectiveness of the proposed strategy.