具有电压补偿功能的微网逆变器控制研究

摘要

The characteristics of microgrid inverter to compensate the voltage sags are theoretically analyzed. Microgrid inverter is influenced by system voltage distortions and harmonics when it is connected into the grid normally. In order to solve the problems, based on an analysis of the performance of the VPI controller, a PVPI control method is proposed which adds an independent proportional term and then applies it in energy storage grid-connected inverter control. Furthermore, a double mode control strategy is presented which makes the inverter realize grid-connected generation control and based on the practical situation converts to PCC voltage sag compensation. Positive sequence and negative sequence PVPI controllers are used to make closed-loop feedback control on positive sequence components and negative ones respectively. Simulation results verify the validity of the proposed control strategy.%　　对微网逆变器用于补偿微网电压暂降进行了理论分析。针对并网逆变器正常并网发电时，微网内电压不平衡、谐波对微网逆变器控制影响，在推导分析 VPI 控制在微电网并网逆变器中应用性能的基础上，提出了一种加入独立比例项的 PVPI控制，并将其应用在基于储能并网逆变器控制中。进一步提出双模式控制方法，使储能并网逆变器既可以实现并网发电控制又可以根据实际情况的需要，将功能切换到补偿PCC电压不平衡暂降，采用正序和负序PVPI控制器分别对正序分量和负序分量进行闭环反馈控制。最后进行了仿真验证，理论分析及仿真结果表明所提方法的正确性和有效性。