使用六绕组隔离变压器的大电流整流器研究

Large current rectifier based on six windings isolated transformer

为提高整流器的电流输出能力,设计了一种基于六绕组隔离变压器的大电流整流器。该整流器使用六绕组隔离变压器作为移相变压器,隔离变压器的原边绕组采用三角形联结,副边绕组相互独立,输出3组相位依次相差120°的单相电压,分别为3组单相整流桥供电,可有效增大电流输出能力。理论分析、仿真及实验结果表明,该大电流整流器的输入侧和负载侧的电能质量与传统的双反星形整流器相同,但电流输出能力为双反星形整流器的1.5倍;另外,该大电流整流器所用隔离变压器的容量要小于双反星形整流器所用变压器的容量,这在一定程度上可以提高该整流器的功率密度。

In order to enlarge the output current of the rectifier, a large current rectifier based on six wind- ings isolated transformer was proposed. In the rectifier, six windings isolated transformer were used to be the phase-shift transformer, and the primary windings of the transformer were connected in delta, the secondary windings are independent and provide three groups of single phase voltage with 120° phase shift in turn to feed three single-phase rectifiers; the three windings of the inter phase reactor connect the output positive electrode of the three single-phase rectifiers, respectively, which can increase the ability of output current. Theoretical analysis, simulation and experimental results indicate that the power quality on the input side and load side of the large current rectifier is the same as the double-star rectifier, and the output current is 1.5 times of the double-star rectifier. In addition, the kVA rating of the isolated transformer is smaller than that of the transformer in the double-star rectifier, which improves the power density of the proposed rectifier to some degree.