含电阻型超导限流器的南澳柔性直流系统故障特性分析

Fault Characteristics Analysis of Nan’ao Flexible DC System with Resistance Superconducting Current Limiter

多端柔性直流输电系统直流侧发生故障时故障电流较大,需要在直流侧配置限流装置。文中以南澳多端柔性直流输电工程为例,首先在PSCAD/EMTDC平台上搭建了含电阻型超导限流器的南澳多端柔直工程仿真模型;其次,在模拟系统直流侧发生极间短路故障工况下,对比分析最大阻值不同的电阻型超导限流器的限流能力,从而确定了限流器的最大阻值;进而,模拟系统直流侧发生负极接地故障,对比分析了未接入限流器和接入限流器两种运行工况下的线路电流电压仿真曲线;仿真结果表明,电阻型超导限流器能有效抑制短路故障电流,可降低系统对直流断路器开断能力的要求,提高系统运行的安全性。

The multi-terminal flexible DC transmission system will emerge a large fault current,when the DC side fault occurs.Thus,a fault current limiting device needs to be installed on the DC side.This paper takes the Nan’ao multi-terminal flexible DC transmission project as an example.First,the simulation model of Nan’ao multi-terminal flexible DC project with resistance superconducting current limiter is built on the PSCAD/EMTDC;Secondly,in the case of an inter-electrode short-circuit fault condition on the DC side of the simulation system,the fault current limiting effects of the resistance-type superconducting current limiters(RSFCL)with different maximum resistance values are compared and analyzed,thereby the maximum resistance value of the RSFCL can be determined;Furthermore,A comparative analysis by simulation was conducted to determine whether a resistive current limiter was used,for an the negative ground fault occurred on the DC side of the simulation system.The simulation results show that the RSFCL can effectively suppress the short-circuit fault current,which can reduce the system’s requirements for the DC circuit breaker and improve the safety of system operation.