多直流馈入异步受端电网恢复的分区方法

针对异步联网时受端系统的恢复问题,提出一种综合考虑网络社团结构特性和交直流交互作用的系统恢复分区方法。首先,在分析交直流系统交互作用的基础上,将系统强度指标纳入分区原则和约束条件中,并优化得到多直流系统的最优传输功率,进而提出了适用于异步受端电网恢复的分区模型。然后,以支路对各直流落点短路容量的综合影响为权重定义了加权边介数,以黑启动电源个数和分区约束条件为判据自动确定分区数量,采用改进的GN分裂算法实现了多直流馈入受端电网恢复的合理分区,并基于分区结果计算出分区恢复时间和负荷恢复总量。最后,IEEE 39节点系统和中国南方某省局部电网的分区结果验证了所提方法的可行性和有效性。

Partition Method for Restoration of Asynchronous Receiving End Power Grid with Multi-infeed HVDC

Aiming at the restoration problem of asynchronous receiving end power grid, a partition method for system restoration is proposed, which considers the structure characteristics of network community and the interaction between AC and DC system. Firstly, on the basis of analyzing the interaction, the system strength indices are added to the partition principle and constraints, and the optimal transmission power of each line commutated converter based high voltage direct current(LCC-HVDC)system is obtained by solving the corresponding optimization model. Then, a partition model is proposed for the asynchronous receiving end power system restoration. Secondly, by taking the comprehensive influence on the bus short-circuit capacity of each HVDC dropping location as the weight, the weighted edge betweenness of branch circuit is defined. The partition number can be automatically determined according to the partition constraints and the number of black start sources. An improved GN splitting algorithm is then used to realize the reasonable partition of the multi-infeed HVDC receiving end power grid. Based on the partition results, the restoration time and load restoration capacity are calculated. Finally, the partition results of the IEEE 39-bus system and a local power grid in a southern province of China verify the feasibility and effectiveness of the proposed method.