基波磁势自平衡谐波抵消式串联有源滤波器

提出一种新型的基于基波磁势自平衡谐波抵消式串联有源电力滤波器.在变流器的二次侧接上一个LC基波串联谐振电路,便可使变流器对基波呈现低电抗,而对谐波呈现高阻抗.同时变流器检测绕组可直接检测出谐波电流波形,并通过变流器的谐波绕组反馈一个与一次侧谐波电流相位相反的电流去抵消系统中剩余的谐波电流.本文阐述了基波磁势自平衡谐波抵消式串联有源滤波器的结构和工作原理,分析了滤波器的谐波放大抑制原理,给出了滤波器的试验方法、结果及分析.试验结果表明此滤波器设计新颖、结构简单、可靠性高,并具有很好的滤波效果,电流畸变率由15.33%降为1.147%.

Series Active Power Filter Based on Fundamental Magnetic Potential Self-Balance and Harmonic Counteraction

A new type series active power filter based on fundamental magnetic potential self-balance and harmonic counteraction is proposed. It is found that if a LC fundamental series-connected resonance branch is connected in the second side of a current converter, the series current converter will present low reactance to fundamental and the high impedance to the harmonics. At the same time, the harmonic current waveform can be measured by the testing winding of the current converter. Thus if a harmonic current proportional and opposite to the phase of the harmonic current of the primary side is injected into the feedback winding, the surplus harmonic current of the power system can be counteracted. The theory of the harmonic magnification restraining is studied. Experiment results show that the design of the filter is novel and the filter possesses the simple structure and the perfect reliability. When the new type series active power filter is used, the current distortion factor in the testing power system is decreased from 15.33% to 1.147%.