基于快速储能的风电潮流优化控制系统

风电功率的间歇与波动致使电场容量可信度低、可调度性差;同时易引起局部电网的电压不稳、频率波动,影响了系统的电能质量及稳定性。针对此现象,将超级电容器与蓄电池组成快速储能装置,用于风电的潮流优化控制。采用三重双向直流变换电路控制储能元件间的功率流动;采用四象限交直流变换电路控制储能与电网间的能量交换。提出基于超级电容器电压低频波动抑制的功率分配方法,可显著减少蓄电池的充放次数;提出基于储能元件荷电状态的储能能量调整规则,可避免储能元件的过充和频繁深度放电,以优化其功率调节能力。实验结果表明,系统可实现2种储能元件的优势互补,能有效平滑调节风电注入电网的有功功率,并实时补偿控制风电接入点的无功功率。

Wind Power Flow Optimization and Control System Based on Rapid Energy Storage

Intermittency and fluctuation of wind power lead to low capacity credit and poor schedulability of wind power plant,and give rise to voltage instability as well as frequency fluctuation in the grid,which negatively affects power quality and stability of power system.To solve this problem,the paper set up rapid energy storage device based on the supercapacitor and the battery,which was used for wind power flow optimization.A triple two-way DC-DC converter was applied to distribute power between two energy storage components,and a four-quadrant DC-AC converter was applied to adjust the energy exchange between the energy storage and the grid.Power distribution method based on low-frequency fluctuation elimination of supercapacitor voltage can significantly reduce the times of charge and discharge of the battery;Storage energy regulation rule based on state-of-charge(SOC) of the energy storage components can avoid overcharge and deep discharge,and optimize power adjustment capability.The experimental results show that the system can realize advantage complementation of both energy storage components,effectively smooth and regulate the active power injected in the grid,and compensate the reactive power at the access point of wind power in real-time.