In order to solve the problem of insufficient economy and practicability of traditional flexible current limiting device in DC grid,a modular current limiting inductance structure and input scheme are proposed in this study as a novel form of DC flexible current limiting device.A corresponding control design strategy is suggested based on this structure.The proposed structure enhances the fault tolerance rate of the flexible current limiting device,improves its economy,and increases the speed and efficacy of fault current suppression.It achieves quick isolation of permanent faults in the DC line and enables self-healing of transient faults without the need for circuit breaker activation.To further confirm the efficacy of the proposed device,a software platform is used to build a multi-terminal flexible DC simulation system.This system investigates both permanent and transient faults in the DC line.
关键词
限流器/电力系统保护/直流电网/经济性/控制层设计/暂态分析
Key words
current limiter/power system protection/DC grid/economy/control layer design/transient analysis