多功能并网逆变器及其在微电网中的应用

提出了一种能同时补偿无功、谐波和不平衡电流的多功能并网逆变器拓扑,并研究了其在微电网中的应用。同时,基于加权电流反馈的思想,给出了一种多功能并网逆变器的滞环电流控制策略。此外,基于同步旋转坐标系的无锁相环电流检测方法,给出了一种多功能并网逆变器参考电流的生成算法。最后,利用PSCAD/EMTDC验证了所提出方法的有效性和正确性。仿真结果表明,所提出多功能并网逆变器在改善微电网电能质量的同时,还能控制微电网与配电网之间的潮流,在必要时可为配电网提供一定的有功和无功支撑。

Multi-functional Grid-connected Inverter and Its Application in Microgrid

A topology of multi-functional grid-connected inverter is proposed and applied to a microgrid.It can compensate harmonic,unbalance and reactive currents of microgrid at the same time.A corresponding controller based on weighted current feedback and hysteresis current loop is also given.Furthermore,an approach to detect compensative current and calculate reference current is given with synchronous rotating frame,which can remove phase lock loop.Finally,PSCAD/EMTDC is used to verify and confirm the proposed methods.The simulation results validate its good performance.It can not only enhance the power quality of microgrid,but also can regulate the power flow between microgrid and utility grid,which can aid the utility grid with necessary active or reactive power.