考虑分布式储能功率四象限输出的主动配电网鲁棒优化调度模型

Robust Optimal Scheduling Model of Active Distribution Network Considering Four-Quadrant Output of Distributed Energy Storage Power

大量分布式电源接入可能会出现配电网电压偏移和网损增加等问题。以考虑配置分布式储能为解决方式,结合储能系统功率四象限输出运行策略,构建了以购电成本、网损成本、电压偏差惩罚的总运行成本最小化为目标函数的主动配电网优化调度模型,并应用区间鲁棒优化模型对风电机组出力和负荷需求的不确定性进行处理。采用二阶锥松弛技术对配电网交流最优潮流进行凸优化松弛,使原优化调度模型转换为可有效求解的二阶锥规划模型,解决了潮流双向流动配电网网络中难以考虑电压的问题。采用Big-M法处理目标函数中含有绝对值的非线性项。整个配电网优化调度模型可转换成一个混合整数二阶锥规划问题,并采用列与约束生成算法对配电网鲁棒优化调度模型进行求解。最后,在IEEE33节点系统中仿真验证了本文所提模型的有效性。

An increasing number of distribution generations(DGs)are being integrated in distribution network(DN),which may cause voltage deviation(VD)and network loss.By considering the distributed energy storage system(DESS)as an effective solution,this paper proposes an optimal scheduling model,the objectives include main network electricity purchasing cost,network loss cost,and voltage deviation penalty combined with the power four-quadrant output control strategy of the battery energy storage system(BESS).Besides,interval robust optimization(RO)model is applied to deal with the uncertainties of wind power output and load demand.The second-order cone relaxation(SOC)technique is used to convexify the power flow equations in the optimization model.Consequently,the original optimal scheduling model is converted to a second-order cone programming(SOCP)problem.It solves the problem which is difficult to consider the voltage in DN.Meanwhile,Big-M method is used to deal with the nonlinear terms with absolute value in the objective function.Therefore,the entire DES optimal scheduling model of the DN is transformed into a mixed integer second-order cone programming problem(MISOCP);and a mature CPLEX solver is invoked to solve the optimal scheduling model.Finally,comparative studies based on IEEE 33 are performed to validate the effectiveness of the proposed methods.