摘要
针对电压源换流器的高压直流输电(VSC-HVDC)系统,首先分析正常运行情况下电压源换流器两侧交、直流电流之间满足的平衡关系。然后将换流器的5种开关模式按照桥臂导通状态分为两类工作状态,分析不同工作状态下全控型电力电子器件绝缘栅双极晶体管(IGBT)阀短路和阀开路的电流流通路径,研究故障后交流侧电流幅值和直流侧电流的变化及其相互关系。在此基础上,提出一种能够反应IGBT阀短路和阀开路的保护方案,将交流侧三相电流采样值分别与各自导通状态函数相乘并求和,并与直流侧电流采样值构成差动电流,利用该差动电流反应阀短路和阀开路故障,并给出保护的整定原则。最后,基于仿真平台搭建双端VSC-HVDC系统模型,验证了该保护方案的有效性。
For the voltage source converter based high voltage direct current transmission(VSC-HVDC),the balance relationship between the AC and DC currents on both sides of the voltage source converter un-der normal operation was analyzed.Then,according to the conducting state of the bridge arm the five switching modes of the converter were divided into two types of operating states,the current flow paths of the insulated-gate bipolar transistor(IGBT)short circuit and open circuit under different operating states were analyzed,and the changes of AC-side current amplitude and DC-side current after the fault and their interrelationships were studied.On this basis,a protection scheme that can reflect the IGBT valve short circuit and valve open circuit was proposed,which multiplies the AC-side three-phase current sampling value and their on-state functions respectively and then sums them,and a differential current was formed with the DC-side current sampling value.The differential current was used to reflect the valve short cir-cuit and valve open circuit,and the setting principle of the protection was given.Finally,the VSC-HVDC system model was built based on the simulation platform,and effectiveness of the proposed protec-tion scheme was verified by simulation.
作者
张艳霞
杜珊珊
马锦婷
董广浩
ZHANG Yanxia;DU Shanshan;MA Jinting;DONG Guanghao(Key Laboratory of Smart Grid of Ministry of Education,Tianjin University,Tianjin 300072,China)
出处
《电机与控制学报》
EI
CSCD
北大核心
2023年第12期31-40,共10页
Electric Machines and Control
关键词
柔性直流输电
绝缘栅双极晶体管
阀短路
阀开路
阀导通状态函数
差动电流
voltage source converter based high voltage direct current
insulated-gate bipolar transistor
valve short circuit
valve open circuit
valve on-state function
differential current
