基于载波相位调节的SPWM逆变器并联系统环流电流抑制方法

Suppression method of circulating current in SPWM inverters parallel system based on adjustment of phases of triangular carrier waves

针对交流电动机驱动用SPWM逆变器并联系统中的环流问题,根据环流电流与载波相位差的关系,提出了一种基于三角载波相位调节的环流抑制方法。基于载波相位调节最小原则,根据环流电流特性确定载波相位差方向,并根据环流电流直流分量与载波相位差的关系确定载波相位差大小来调节相位超前的三角载波相位以达到抑制环流电流的目的。仿真结果表明:该环流电流抑制方法具有可行性。

Aiming at the circulating current in the SPWM inverters parallel system for AC motor drive, this paper proposes a suppression method of circulating current based on the relationship be- tween the circulating current and phase difference of carrier waves. The direction of the phase diffe- rence of carrier waves is determined according to the principle of the minimal accommodation, and then the value of the phase difference is computed according to the relationship between the DC circu- lating current and the phase difference of carrier waves. The adjustment of the lagging phase of the anterior triangular carrier wave according to the phase difference and the direction of triangular carrier wave can suppress the circulating current effectively. The simulation result proves the proposed method to be effective and feasible.