一种基于直流侧有源注入的12脉波之字形自耦变压整流器

为提高多脉波整流器的谐波抑制能力,提出了一种基于直流侧有源补偿策略的之字形自耦变压整流器.通过控制小容量电流逆变器产生补偿电流,并将补偿电流直接注入到系统的直流侧使整流器输入电流近似为正弦波.使用之字形自耦变压器作为移相变压器以阻断零序电流成分,降低整流系统的等效容量.研究网侧电流谐波畸变率随负载的变化规律表明,在各种负载条件下,补偿后的整流系统谐波含量显著降低.所提出的有源注入整流系统的网侧电流谐波含量仅为1.17％,且具有较低的等效容量.

A low harmonic 12-pulse rectifier based on zigzag autotransformer by current injection at DC side

To improve the harmonic suppression ability of multi-pulse rectifier,a 12-pulse rectifier based on zigzag autotransformer by DC side active compensation strategy is proposed.By controlling the small capacity current inverter to generate compensating currents and injecting the currents directly into the DC side of the system,the grid-side currents of the rectifier can be approximated to sine wave.Using zigzag autotransformer as phase-shifting transformer can block the zero sequence current components and reduce the equivalent capacity of the rectifying system.The study on harmonic distortion rate of grid-side currents with the variation of the load shows that the harmonic content of the compensated rectifier decreases significantly under various load conditions.The harmonic content of the grid-side currents of the proposed active injection rectifier is only 1.17％,and the equivalent capacity of the rectifier is calculated.The results show that the rectifier can not only suppress the harmonic currents,but also have a lower equivalent capacity.