四桥臂三相逆变器的控制策略

提出了一种新型的三相四线逆变器，它有四个桥臂，第四个桥臂用来构成中点，从而省去了三相三桥臂逆变器中的中点形成变压器，减小了逆变器的体积和重量。针对这种逆变器，本文提出了一种电流调节器，它根据三相滤波电感电流和给定电流的误差值最大的那相选择逆变器的开关模态。为了消除输出相电压的静态误差，本文讨论了一种基于ＰＩ调节器改进的电压调节方案。仿真结果表明，本文的思路是可行的。本文为构造大功率、高效率的三相四线逆变器提供了可靠的理论基础。

The Control Strategy for Three-Phase Inverter with Four Bridge Legs

A novel three-phase inverter with four bridge legs is presented in this paper. The inverter e liminates the neutral forming transformer by adding a bridge leg to form neutral point to provide balanced volt ages to any kinds of three phase loads. The principle of the inverter is analyzed, and a new current regulator, which chooses switching modes according to the maximum current error of filter inductance current and the ref erence current is proposed. The modified voltage regulator on the basis of PI regulator is proposed to eliminate output voltage static error under any load conditions.