摘要
高压内置型高阻抗变压器空载合闸中会产生幅值较高的零序涌流,其可能会经相邻变压器渗透至经小电阻接地的20 kV配电网络中,引发配网线路零序过流保护误动,进而导致用户失电。针对这一问题,首先结合零序涌流的半解析表达式,对高压内置型高阻抗变压器的零序涌流幅值特征进行量化分析;然后依托PSCAD/EMTDC平台验证了模型的有效性和保护误动的可能性;最后基于Matlab编写配网线路零序过流保护的误动风险评估程序,结合变压器和保护的实际参数,量化高压内置型高阻抗变压器空载合闸工况下相邻配网线路零序过流保护的误动概率。计算结果明确零序过流保护在高压内置型高阻抗变压器空载合闸期间的动作情况,在此基础上,提出一种借助5G通信技术的零序过流保护涌流闭锁策略,并分析该策略的可行性。
The high zero-sequence inrush will be caused when the high-voltage built-in high-impedance transformer performs no-load closing,which may penetrate into the 20 kV distribution network with a grounding small resistance through the adjacent transformers,leading to the maloperation of zero-sequence overcurrent protection of distribution lines.This will result in the power loss of users.To solve this,the amplitude characteristics of high-voltage built-in high-impedance transformers are analyzed based on zero-sequence inrush formula.Then,the validity of the model and the possibility of protection maloperation are studied based on PSCAD/EMTDC simulation platform.At last,the calculation procedure for assessing risks of zero-sequence over-current protection in distribution networks is produced by MATLAB,where the actual parameter is used to quantitatively analyze the maloperation probability of zero-sequence overcurrent protection when a high-voltage built-in high-impedance transformer performs no-load energize.The experienmental results indicate protection operation situations.A protection blocking strategy based on 5G wireless communication technology is proposed and its feasibility is analyzed.
作者
彭业
金震
陈宏山
徐舒
罗长兵
侯炜
何进锋
陈俊
PENG Ye;JIN Zhen;CHEN Hongshan;XU Shu;LUO Changbing;HOU Wei;HE Jinfeng;CHEN Jun(China Southern Power Grid Co.,Ltd.,Guangzhou 510080,China;Nari-relay Engineering and Technique Co.,Ltd.,Nanjing 211102,China)
出处
《电力科学与技术学报》
CAS
北大核心
2022年第5期100-108,132,共10页
Journal of Electric Power Science And Technology
基金
中国南方电网有限责任公司科技项目(0000002020030103XT00046)。
关键词
配电网
零序涌流
零序电流保护
风险分析
5G无线通信技术
distribution network
zero-sequence inrush
zero-sequence current protection
risk analysis
5G wireless communication technology
