微电网混合储能系统充放电控制策略研究

Research on Charge and Discharge Control Strategy of Micro-Grid Hybrid Energy Storage System

考虑到由蓄电池和超级电容组成的混合储能系统有利于稳定微电网直流母线电压和优化充放电过程,提出了一种基于直流母线电压稳定的混合储能系统充放电控制策略。该控制策略以直流母线电压稳定为控制目标,实现混合储能系统外部功率平衡,结合超级电容的快充能力和蓄电池的续充能力,以超级电容电压和蓄电池的荷电状态为判断条件,实现混合储能系统内部功率平衡。在Matlab/Simulink环境构建孤岛模式下微电网混合储能系统模型,分析了微电网混合储能系统在负荷功率波动时的运行特性,仿真结果验证了该控制策略在稳定直流母线电压同时降低了蓄电池的充放电次数。

Considering hybrid energy storage system composed with the battery and super capacitor , this system has positive effects on stabilizing the micro？grid DC bus voltage and optimizating charging and discharging process. A charge and discharge control strategy for hybrid energy storage system based on DC bus voltage stability is proposed. The control strategy regarded the stability of DC bus voltage as the control target to realize external power balance of energy storage system. Combined with the fast charge capacity of super capacitor and recharge capacity of battery, as well as the super capacitor voltage and battery charge state （state of charge, SOC） the determined conditions to achieve external power balance of energy storage system. Finally, the model of micro？grid hybrid energy storage system is established in Matlab/ Simulink environment and then analyzed the operation characteristics of micro？grid hybrid energy storage system with load power fluctuation. The simulation results verified that the proposed control strategy not only stabilized DC bus voltage but also reduced the times of battery charge and discharge.