计及柔性负荷的高比例风光渗透下配电网孤岛划分策略

Islanding strategy for distribution network with high proportion ofwind /photovoltaic penetration considering flexible load

含分布式电源(DG)的配电网孤岛运行时存在电源出力不确定及负荷波动等问题,为确保孤岛能稳定可靠地供电,文中提出计及孤岛备用需求并充分发挥柔性负荷调控能力的动态孤岛划分策略。首先,建立考虑风电、光伏不确定性的预测误差模型,使用深度优先搜索算法得到各时段最大供电范围,采用机会约束规划来处理模型中的随机变量并根据最大供电范围得到各时段的孤岛备用需求。然后,通过改进的粒子群优化(PSO)算法充分发挥柔性负荷的调控能力,以故障恢复期间等效恢复价值最大为目标,得到在各置信水平下满足备用需求的最优孤岛划分结果。最后,以修改后的IEEE 33节点系统为例,验证了所提策略在确保孤岛可靠性的同时可有效增加孤岛价值。

There are problems such as uncertain power output and load fluctuation when the distribution network with distributed generator(DG)operates on an island.In order to ensure stable and reliable power supply for islands,a dynamic island partition strategy is proposed which takes into account the standby demand of islands and gives full play to the flexible load regulation ability.Considering the uncertainty of wind power and photovoltaics,a prediction error model is established at first.The depthfirst search algorithm is used to obtain the maximum power supply range for each time period,and chance constrained programming is used to deal with the random variables in the model,the island standby demands for each time period is obtained by the maximum power supply range.Then,modified particle swarm optimization(PSO)algorithm is used to give full play to the control ability of flexible load,and the optimal islanding results that meets the standby demand under each confidence levels is obtained with the objective of maximizing the comprehensive recovery value during the failure recovery period.Finally,a modified IEEE 33 node power distribution system is taken as an example to verify that the proposed strategy can effectively increase the value of islands while ensuring the reliability of islands.