一种新的三相4桥臂逆变器及其控制策略

三相4桥臂逆变器与传统三相逆变器不同。第4桥臂的引入,加上负载的不确定性,使得空间矢量调制控制变得非常复杂,从分析对称三相逆变器每相能独立工作出发,通过引入一特定结构的三相变压器并视其为负载,通过控制第4桥臂来控制负载中点电压,既实现了三相负载的解耦,又能使输出相电压达到220 V。仿真实验证明,该结构与方法对不同性质负载都有很好的适应性,并且容易实现。

New Topology of Three-phase Four-leg Inverter and Its Control Strategy

A three-phase four-leg inverter is much different from a traditional three-phase inverter.With an additional leg is introduced into the traditional three-phase inverter,the old space vector modulation control is very complex with respect to uncertain loads.This paper designed a new topology of three-phase four-leg inverter by introducing a certain three-phase transformer and view it as loads,by controlling the operation of the forth leg,we can control the voltage of the neutral point,which can output 220 V voltage and achieve the decoupling of three phases.The simulation results proved it adapts to balanced and unbalanced loads.