一种新的采用低自感串联变压器的串联混合型有源电力滤波器

A New Series Hybrid Active Power Filter With Small Self-inductance Series Transformer

为降低逆变器容量和提高系统可靠性,该文提出一种新的采用低自感(或自阻抗)串联变压器的串联混合型有源电力滤波器。不同于传统结构,该混合滤波系统中的串联变压器自感很小,其标幺值仅为0.01～0.10,且串联有源滤波器不再控制为谐波电压源或基波电流源,而是控制为谐波电流源。在该方案中,逆变器和串联变压器二次侧绕组均无须承受很大的系统基波电流,而只承受一定倍数的滤波后系统谐波电流,其代价是逆变器在原来承受谐波电压的基础上叠加承受1～10%的系统基波电压。另外,该拓扑无须谐振于基波频率的LC旁路,降低了整个滤波装置的成本、损耗。仿真和实验结果表明,该新型滤波器具有良好的滤波效果。

In order to reduce inverter capacity and enhance system reliability, a new series hybrid active power filter with small self-inductance series transformer （ST） is proposed in this paper. Different from conventional scheme, the self-inductance of the ST in this filtering system is very small about 0.01-0.10 in per unit, and the series active filter is controlled as a harmonic current source instead of a harmonic voltage source or a fundamental current source. In this scheme, both the inverter and the secondary of the ST needn＇t endure the source fundamental current but only endures a certain times of the filtered source harmonic currents, and no LC fundamental tuned circuit is needed, so the cost and dissipation of the whole filtering system can be cut down a 10t. The excellent filtering effects of the filter are verified by both the simulation and experiment results.