基于局部拓展理论的直流多馈入系统分区方法  

Segmentation method of a multi-infeed LCC system based on local fitness measure

作　　者：曹昕 韩民晓[1] 马立民 郭知非 蔡万通 张夏辉 文俊[1] CAO Xin;HAN Min-xiao;MA Li-min;GUO Zhi-fei;CAI Wan-tong;ZHANG Xia-hui;WEN Jun(School of Electrical and Electronic Engineering,North China Electric Power University, Beijing 102206, China;Electric Power Research Institute of CSG, Guangzhou 510663, China)

机构地区：[1]华北电力大学电气与电子工程学院,北京102206 [2]南方电网科学研究院,广东广州510663

出　　处：《电工电能新技术》2021年第6期32-42,共11页Advanced Technology of Electrical Engineering and Energy

基　　金：直流输电技术国家重点实验室开放基金项目(SKLHVDC-2020-KF-19)。

摘　　要：针对多回电网换相型高压直流输电(LCC-HVDC)馈入的交流系统容易发生同时换相失败的问题,本文采用了对多馈入系统进行电网分区的方案,以隔断多回直流之间的耦合,减少发生同时换相失败概率。首先,对多馈入系统进行N-1故障扫描,找出三永交流故障能够引起多回直流发生同时换相失败的线路集合,并将线路负载率较高的线路从线路集合中剔除。随后,基于局部拓展理论对系统中的节点进行自下而上的聚合,形成初始分区。在此过程中,首先给出了考虑PV节点和传统直流的电压/无功灵敏度矩阵的计算方法,随后采用节点聚合度函数和分区适应度函数分别计算节点聚合度和分区适应度。最后,综合考虑线路集合和分区短路比对分区结果进行修正,并给出了分区方案的流程。以IEEE 39节点系统为参考给出了算例,对整个分区过程进行验证。并结合某实际电网给出了分区方案。There is a great possibility of simultaneous commutation failure for LCC-HVDC when there exists multi-infeed into one AC system.To tackle this issue,one segmentation approach to the AC system is proposed in this paper.By dividing the multi-infeed AC system into several parts,the coupling between the LCC-HVDCs will be eliminated,thereby reduce the probability of simultaneous commutation failure of LCCs.Firstly,lines whose three-phase permanent fault will cause simultaneous commutation failure are selected by N-1 fault scanning on the multi-infeed system,among which lines with high load rate are removed.After that,based on the local fitness measure theory,nodes in the system are aggregated from bottom to top to form the initial partition.In this process,the calculation method of voltage/reactive power sensitivity matrix considering PV node and LCC-HVDC is firstly presented.Then the node aggregation function and partition fitness function are applied to calculate the node aggregation and partition fitness,respectively.Finally,considering the line collection and short-circuit ratio,the partition result is modified,and establishes the segmentation process.The effectiveness of the whole segmentation process is verified on IEEE 39 nodes system,and a segmentation scheme is proposed on an actual power grid.

关 键 词：多馈入系统 传统直流 电网分区 N-1预想事故集 局部拓展理论 

分 类 号：TM7[电气工程—电力系统及自动化]