摘要
馈入同一交流系统的多回传统直流(LCC-HVDC)存在发生同时换相失败的可能,通过柔性直流(VSC-HVDC)实现交流电网的分区运行是解决该问题的方法之一,而柔性直流接入位置的确定方法是实现分区互联的重要研究内容。首先,基于雅可比转移矩阵搭建了考虑电网换相换流器(LCC)和电压源型换流器(VSC)的全系统微增量模型,计算了VSC的运行阻抗,进而计算出基于阻抗的有效短路比(IESCR)。随后,对分区拓扑进行了理论分析,得到了VSC-HVDC接入位置、传输功率和IESCR的关系。而后,充分考虑正常运行和N-1运行状态,提出了包括IESCR在内的9个评价指标,给出了VSC-HVDC接入位置的评价流程。基于IEEE 39节点模型给出了算例,对3个VSC-HVDC接入位置计算出了各评价指标的值并给出了得分,确定了其中的最优接入位置。
There is the possibility of simultaneous commutation failure when multi-infeed line commutated converter based high voltage DC(LCC-HVDC) transmission connects to the same AC system. One of the methods to solve this problem is to realize the segmented operation of the AC power grid through voltage source converter based high voltage DC(VSC-HVDC) transmission.The method for determining the accessing location of VSC-HVDC is important research content to realize the segmented interconnection. Firstly, based on Jacobian transfer matrix, a small signal model of the AC system is built when considering both line commutated converter(LCC) and voltage source converter(VSC). Therefore, the operation impedance of VSC is calculated,and the impedance based effective short circuit ratio(IESCR) is calculated. Secondly, the segmentation topology is theoretically analyzed, and the relationship among the accessing location of VSC-HVDC, the power transmission of VSC-HVDC and the IESCR is obtained. Thirdly, by fully considering the normal and N-1 operation states, nine evaluation indices including IESCR are proposed, and the evaluation process of VSC-HVDC accessing locations is given. Based on the IEEE 39-bus model, a calculation example is given. The value of each evaluation index is calculated for three VSC-HVDC accessing locations and the scores are given to determine the optimal accessing location.
作者
曹昕
韩民晓
邵红博
于琳琳
周光阳
CAO Xin;HAN Minxiao;SHAO Hongbo;YU Linlin;ZHOU Guangyang(School of Electrical and Electronic Engineering,North China Electric Power University,Beijing 102206,China;Electric Power Research Institute of State Grid Henan Electric Power Company,Zhengzhou 450052,China)
出处
《电力系统自动化》
EI
CSCD
北大核心
2021年第13期20-29,共10页
Automation of Electric Power Systems
基金
国家重点研发计划智能电网技术与装备重点专项资助项目(2016YFB0900600)。
关键词
电网分区
LCC-HVDC
VSC-HVDC
接入位置
运行状态
基于阻抗的有效短路比
评价指标
power grid segmentation
line commutated converter based high voltage DC(LCC-HVDC)
voltage source converter based high voltage DC(VSC-HVDC)
accessing location
operation state
impedance based effective short circuit ratio(IESCR)
evaluation index
