采用滑模变结构直接功率控制的回馈级联型逆变器设计与验证

Design and Verification of Feedback Cascaded Inverter Using Sliding-mode Variable-structure Direct Power Control

回馈逆变器因可实现能量的双向流动而广泛运用于负载需要4象限运行的场合。为此,对回馈级联型逆变器(EFCI)进行了深入研究。对回馈级联型逆变器H桥整流部分,实现了滑模变结构直接功率控制(SMVR-DPC),除了可实现H桥有功、无功和直流电压控制外,还可减小逆变器输入电流中的谐波,该方法控制简单,具有很好的动态品质和鲁棒性以及小的总谐波畸变率(THD)。对回馈级联型逆变器H桥逆变部分,为了提高直流电压利用率并减小逆变器输出电流中的谐波,对其在60°坐标系中基于3电平逆变器的简化空间矢量调制进行了研究,该简化空间矢量调制的矢量选取与作用时间计算非常简单。最后,仿真与实验结果验证了所提方法的正确性。

Feedback inverters are widely used in four-quadrant operation load situations because of the two-way tlow of energy. We focused on feedback cascade inverter{EFCI}. The active power, reactive power and DC voltage of H bridge could be controlled with sliding mode variable-structure direct power control（SMVR DPC）for the H bridge＇ rectifier of EFCI, and SMVR-DPC could reduce the input current harmonic content of inverter. The control was simple and had a good dynamic quality, robustness, and small total harmonic distortion （THD）. In order to improve efficiency of DC voltage and to reduce the output current harmonics, simplified space vector modulation was realized in a 60~ coordinate system for the inverter part of EFCI, in which it was very simple to select space vector and to calculate vector time. Finally, simulation and experimental results verify the correctness of the proposed method.