无功动态补偿的光储微电网并网控制

Grid connected control of PV and battery micro-grid with dynamic reactive power compensation

针对由用户侧无功负荷变化导致的光储微电网并网点电能质量变差的问题,同时为降低系统复杂度,提出一种自然坐标系下无功动态补偿的光储微电网并网控制策略。该策略以蓄电池的荷电状态切换变流器的控制方法来维持直流母线电压的稳定。针对不同的工况条件设计了两种具有无功动态补偿功能的并网逆变器功率控制策略,实现并网点电压的稳定,同时,在自然坐标系下实现了并网逆变器有功、无功功率的独立控制,省去了坐标变换和电网相位检测。实验结果表明,所提出的控制策略可以实现光储微电网系统功率的平稳有效流动,达到无功补偿的目的,且具有较好的动态响应。

Due to the changes of reactive load in the user side,the power quality at the grid-connected point of PV and battery micro-grid becomes worse. And in order to reduce the complexity of the control system,a synchronization control strategy under natural coordinate with the capacity of dynamic reactive power compensation for PV and battery generation system is proposed. In order to maintain the stability of the DC bus voltage,the converter control methods are switched according to the state of battery charge. Two different control strategies of inverter connected grid for reactive power compensation are designed according to the different working conditions then the stability of grid-connected point voltage is realized. Under natural coordinate,the active and reactive power of inverter can be controlled independently without coordinate transformation and phase detection of the grid. The experimental results show that the proposed control strategy can realize a good dynamic response and smooth and effective power flow then achieve the purpose of reactive power compensation.