基于混合储能的并网光伏发电系统功率控制研究

针对并网光伏发电系统输出功率的波动,提出利用混合储能系统对功率进行平抑.介绍了光伏最大功率跟踪和并网逆变的控制,为实现发电和并网功率的匹配,考虑蓄电池和超级电容器各自特性的优势,对混合储能系统提出了三级式功率分配策略;通过设计相应的控制方法和以功率分配单元的输出功率作为参考值,混合储能系统控制变换器进行合理充放电.混合储能系统不仅保证了并网功率按计划运行,而且稳定了直流母线电压、满足了随机负荷供电.通过仿真验证,三级式功率分配策略有效,控制方法可行.

Power Control of Grid-connected Photovoltaic Power Generation System Based on Hybrid Energy Storage

In view of the fluctuant power of grid-connected photovoltaic power generation system, the hybrid energy storage system is used to overcome it. First, Maximum Power Point Tracking and grid-connected DC/ AC conversion are introduced. For matching power of generation and grid-connection and considering respec- tive characteristic of battery and super capacitor, three levels of power allocation strategy is provided for the hybrid energy storage system. Then through designing the corresponding control method and using output power of power distribution unit as the reference value, hybrid energy storage system reasonab!y controls converters to charge and discharge. Hybrid energy storage system not only ensures the grid-connected power according to plan, but also stabilizes the DC bus voltage and meets the power supply of the random loads. The simulation results show, the three levels of power allocation strategy is effective, the control method is feasible.