基于图论和OBDD的含分布式电源配电网故障恢复算法

Service restoration algorithm for distribution network with distributed generation based on graph theory and OBDD

为快速确定含分布式电源(DG)配电网故障恢复的最优方案,首先,提出了基于改进Bellman-Ford算法的含多DG配电网孤岛划分图论模型,该模型综合考虑DG发电成本、网损及负荷优先级确定孤岛范围,转换为孤岛运行以提高重要负荷的供电可靠性。然后将DG孤岛外故障恢复问题转化为约束满足的布尔型决策问题的三步法:(1)根据节点类型将节点按位编码分区枚举生成初始解空间;(2)定义电源约束、负荷损失约束和辐射状约束的布尔函数,合成为OBDD模型减少解空间中解数量;(3)对解空间中的解逐一进行校验、寻优切负荷及排序,稳定获得系统故障恢复的全局最优解。最后通过IEEE33节点系统和某地区实际配电网验证了该算法的有效性。

In order to quickly determine the optimal solution for service restoration of distribution network with distributed generation,we first propose a graph model based on improved Bellman-Ford algorithm for islanding of multi-DG distribution network,which considers DG costs,network loss and load priority to determine the island range,and then transform it into island running to improve the reliability of power supply for important loads.Then the external service restoration of DG island is converted to the three-step method of constraint satisfaction problem.Firstly,the load buses are partitioned by bit according to the bus type and the initial solution space is generated through enumeration.Secondly,the constraint functions of power source,load loss and radiation are defined as the OBDD model to substantially reduce the scale of the solution space.Thirdly,each service restoration scheme in the space is checked,load shed and prioritized,then,the optimal service restoration scheme is obtained according to the sorting result.Finally,the feasibility and effectiveness of the service restoration algorithm are verified by the calculation results of IEEE33 system and a regional 10kV distribution network.