一种多功能模块化直流故障限流器拓扑及控制策略

直流故障限流器(FCL)作为是抑制限制直流短路故障电流的关键重要设备之一,在交直流混合电网输电系统中应用中作用十分重要。得到广泛应用,在故障发生时能有效限制故障电流的激增。针对传统直流限流器仅具备限流功能且故障电流无法被完全限制的问题,本文提出一种多功能模块化直流故障限流器拓扑,在分析其工作机理的基础上,分别针对故障限流、能耗泄放和直流网压支撑三种功能,完成了相应及其控制策略开发。,实现了多种故障情况下采用对应故障限制功能,有效抑制故障电流,稳定直流侧电压。为验证拓扑结构及控制策略的有效性,在Matlab/Simulink中搭建构建交直流混合输电极间短路故障及模块化限流器系统多工况模型,仿真结果表明所提出的模块化直流限流器拓扑及控制策略,满足交直流混合电网多种故障情况下的故障限流需求,可维持直流网压的稳定。能有效限制直流短路故障。

Topology and control strategy of a multifunctional modular DC fault current limiter

Dc fault limiter (FCL) is a key device to suppress dc short circuit fault current and plays an important role in the application of AC/DC hybrid power grid. In this paper, a multifunctional modular DC fault limiter topology is proposed. On the basis of analyzing its working mechanism, three functions of fault current limiter, energy consumption discharge and DC network pressure support are respectively targeted, and corresponding control strategy development is completed. The simulation results show that the proposed modularized DC limiter topology and control strategy can meet the fault current limitation requirements of ac-DC hybrid network under various fault conditions and maintain the stability of DC network voltage.Dc fault limiter (FCL), as one of the important devices to limit DC faults, has been widely used in AC-DC hybrid transmission system, which can effectively limit the surge of fault current when faults occur. The traditional DC current limiter only has the function of current limiter and the fault current cannot be completely limited, a multifunctional modular DC fault limiter and its control strategy are proposed, which can effectively suppress the fault current and stabilize the DC side voltage by adopting the corresponding fault limiter function under various fault situations. In order to verify the effectiveness of topology structure and control strategy, a model of ac-DC hybrid transmission electrode short-circuit fault and modular current limiter was built in Matlab/Simulink. The results show that modular current limiter can effectively limit dc short-circuit fault.