为了改善变电站的220 kV供电网的电能质量，提出一种四绕组感应滤波变压器(FW-IFT)组合无源滤波装置的IF方法来屏蔽电网负荷侧的特定次谐波，使其无法窜入供电网。阐述了新型IF方案，详细分析了FW-IFT的IF机理。然后，基于辐射型电路建立基波与谐波下FW-IFT的电压方程，并分析了滤波性能。最后，通过MATLAB仿真和样机试验，验证了所提方法是有效可行的。

In order to enhance the power quality of the 220 kV supply grid of a distribution substation, a novel inductive filtering (IF) method with a four-winding inductive filtering transformer (FW-IFT) connected to passive filters is proposed to prevent the main load harmonic current from flowing into the supply grid. A new IF scheme is introduced and the IF mechanism of the FW-IFT is analyzed in detail. Then, the voltage equations of the FW-IFT under fundamental and harmonic frequencies are established based on the radial circuit, and the filtering performance is analyzed. Finally, the effectiveness and feasibility of the proposed method is verified by MATLAB simulation and prototype experiment.

湖南省教育厅一般项目（19C1674）;邵阳市科技计划项目(2019RC53)