预防暂态低频减载的储能容量配置多目标动态优化方法

Multi-objective Dynamic Optimization Method for Capacity Configuration of Energy Storage System to Mitigate Transient Under-Frequency Load Shedding

在系统受到扰动而引起频率下降的暂态过程中,如果瞬时频率过低,将会触发不必要的低频减载,导致系统的供电可靠性降低。储能由于其具有快速功率调节能力,可以避免不必要的暂态低频减载。首先,基于电力系统等值频率响应模型提出了适合储能容量配置的具有分段函数约束的多目标动态优化模型,旨在同时考虑储能配置成本和暂态频率调节性能2个相互冲突的目标。然后,采用大M法和隐式梯形积分法将多目标动态优化模型转化为多目标混合整数二次规划模型。采用规格化法平面约束法和CPLEX求解器获得其帕累托最优解。最后,基于IEEE 24节点系统的仿真计算验证了所提多目标储能配置模型的有效性。

During the frequency decline process of a power system subject to a disturbance,unnecessary under-frequency load shedding will be triggered if the instantaneous frequency is too low. This will reduce the power system reliability.Energy storage can be used to mitigate the unnecessary transient under-frequency load shedding due to its fast power regulation ability. According to the equivalent frequency response model of power systems,this paper proposes a multiobjective dynamic optimization model with piecewise function constraints which is suitable for the configuration of energy storage capacity. This model aims to consider two conflict objectives at the same time,such as the cost of energy storage configuration and the performance of transient frequency regulation. The big-Mmethod and implicit trapezoid integration method are used to transform the multi-objective dynamic optimization model into a multi-objective mixed integer quadratic programming model. Then the normalized normal constraint method and CPLEX solver are used to obtain the Pareto optimal solution. Finally, the effectiveness of the proposed multi-objective optimization model of energy storage capacity configuration is validated with the simulation result on the IEEE 24-bus system.