三相并网/独立双模式逆变器控制策略研究

摘要

提出了一种使三相并网/独立双模式逆变器（TDMI）在复杂电网故障情况下能够平滑切换和电网正常时具有很好并网性能的控制策略。针对采用LC型滤波器的三相并网/独立双模式逆变器,提出了一种新的基于abc坐标系控制的切换方法,有效减小了基于dq坐标系控制的切换过程易产生电压电流冲击的问题,对于严重电网故障也具有良好的切换性能,实现了双模式运行的平滑切换;采用了并网模式下引入电容电流补偿的电感电流闭环控制和独立模式下采用电容电压外环电感电流内环的控制方案,保证了逆变器在并网模式和独立模式下都具有很好的控制性能。仿真结果证明了该控制方案的有效性和切换方法的可行性。%This paper proposes a control strategy which makes three-phase double mode inverter（TDMI）transfer seamlessly in complicated grid fault conditions and has a good performance in grid-tied condition when grid is normal.This paper studies the problem of TDMI which uses a LC filter,proposes a new transfer method based on controller in abc coordinates which reduce transient problem caused by controller based on dq coordinate and make transfer seamlessly.It chooses a close loop control of inductire current compensated by capacitor current in grid-tied mode and double feedback loop of capacitor voltage and current in stand-alone mode for inverter with a good property in these two modes.The simulation results show the validity of propose control strategy.