计及移相角的多边形自耦变压器12脉波整流系统分析

多边形自耦变压器一定程度上减小了整流系统的体积,节约了变压器制造成本。为使多边形自耦变压器输出较大的二次侧电压值,优化多边形自耦变压器移相角,分析多边形自耦变压器移相角对12脉波整流系统输入侧电流谐波总畸变率,输出侧电压纹波系数,变压器、平衡电抗器、零序电流抑制器等效容量的影响;对比移相角在π/6、π/2时各个参数的值;提出适用于升压场合的多边形自耦变压器升压移相角;仿真实验验证了理论分析的正确性。同匝比时,多边形自耦变压器采用新移相角其输出电压幅值约为输入电压幅值1.4142倍,等效容量约为62.8%,较传统隔离式变压器等效容量小约37.2%。

Phase-shift Angle Analysis on 12-pulse Rectifier with Polygon-connected Autotransformer

Polygon-connected autotransformer can reduce the volume of the rectifier system and save the manufacturing cost.To obtain a larger secondary side output voltage value of the autotransformer,this paper optimized the phase-shift angle of the Polygon-connected autotransformer.The influence of the phase shift angle on the total harmonic distortion of the input current,output voltage ripple coefficient,Polygon-connected autotransformer equivalent capacity,interphase reactor equivalent capacity and zero sequence blocking transformer equivalent capacity was analyzed.The value of every parameter under phase-shift angle ofπ/6 andπ/2 was compared.The step-up phase-shift angle applicable to the Polygon-connected autotransformer was proposed.Some simulations were done to verify the correctness of the analyses.Under the same turn ratio,the equivalent capacity of the Polygon-connected autotransformer is about 37.2%less than the traditional isolating transformer and the output voltage of the Polygon-connected autotransformer using the new phase-shift angle is 1.4142 greater than the input voltage.