孤岛模式下光储直流微电网变功率控制策略

摘要

由于直流微电网中常用的分层控制方法具有微电网母线电压波动较大、蓄电池控制模式切换的次数较多、微电网的冗余功率较大的缺点,为此提出了变功率控制方法.以光伏电池、蓄电池和负荷构成的孤岛式直流微电网为研究对象,设计以光伏输出和负荷消耗的功率差为基准,调节蓄电池充放电的方向、功率的大小以及微电网的工作模式.MATLAB/Simulink仿真结果验证了所提控制方法的有效性和可行性,且所提控制方法能够实现微电网功率的平衡和电压的稳定,其控制性能明显优于常用的分层控制方法.%Aiming at the larger bus voltage fluctuation,more frequent battery control mode switching and richer redundant power of DC microgrid in normal hierarchical control,a strategy of variable power control is proposed.For the islanded DC microgrid consisting of photovoltaic cells,batteries and loads,it is designed to take the difference between its photovoltaic output power and load power as the reference to regulate the power and direction of battery charge/discharge and its operating mode.The effectiveness and feasibility of the proposed strategy are verified by the simulative results with MATLAB/Simulink,which shows that,the balanced power and stable voltage of microgrid are realized and its control performance is better than that of the hierarchical control.