摘要
研究模块化多电平换流站直流侧故障的暂态特性,对直流系统保护配置的设计、系统参数的优化等有重要的工程意义。考虑直流线路对地电容的影响,提出了一种直流侧单极接地故障电流计算方法。首先对直流线路进行π型等效处理,分析了MMC-HVDC系统在三种不同接地方式下的直流侧单极接地故障电流的产生机理。对不同接地方式下的换流站进行数学建模,基于基尔霍夫定律建立系统的微分方程,通过Matlab求解系统的故障电流。基于PSCAD/EMTDC仿真平台,建立MMC-HVDC直流系统模型。仿真结果验证了故障电流算法的精确性。
Studying the transient characteristics of DC side faults of a modular multilevel converter(MMC)has important engineering significance for the design of DC system protection configuration and optimization of system parameters.Considering the influence of DC line capacitance on ground,this paper proposes a DC-side single-pole ground fault current calculation method.First,π-type equivalent processing is applied to the DC line,and the generation mechanism of the DC-side single-pole ground fault current in the MMC-HVDC system under three different grounding modes is analyzed.The mathematical modeling of the converter station under different grounding modes is carried out.Based on Kirchhoff's law,the differential equation of the system is established,and the fault current of the system is solved by Matlab.Based on the PSCAD/EMTDC simulation platform,the MMC-HVDC DC system model is established.The simulation results verify the accuracy of the fault current algorithm.
作者
彭宇锋
张英敏
李俊松
刘天琪
刘麒麟
PENG Yufeng;ZHANG Yingmin;LI Junsong;LIU Tianqi;LIU Qilin(College of Electrical Engineering,Sichuan University,Chengdu 610065,China)
出处
《电力系统保护与控制》
EI
CSCD
北大核心
2020年第23期57-63,共7页
Power System Protection and Control
基金
国家重点研发计划项目资助(2018YFB0904600)。
关键词
高压直流输电
MMC-HVDC
单极接地故障
故障电流计算
线路等效
high voltage direct current transmission
MMC-HVDC
pole-to-ground fault
fault current calculation
line equivalent
