具备潮流控制功能的多端口混合式直流断路器

针对多端柔性直流电网的故障保护和潮流控制问题，该文提出一种具备潮流控制功能的多端口混合式直流断路器，由通流支路、主断路器支路两部分构成。当系统正常稳态运行时，该断路器具有潮流控制功能，可用于调节支路潮流；系统发生故障后，相当于混合式直流断路器，用于切断故障电流。建立了具备潮流控制功能的多端口混合式直流断路器拓扑，阐述了稳态和暂态运行机理，并进行经济性分析。最后，在PSCAD仿真平台搭建了四端直流输电系统，验证了所提拓扑在潮流控制和故障切除方面具有良好的性能。

Multi-port Hybrid DC Circuit Breaker With Power Flow Control

Aiming at the fault protection and power flow control problems of the multi-terminal flexible DC grid, this paper proposed a multi-port hybrid DC circuit breaker with power flow control function. The proposed breaker consists of two parts: the through-flow branch and the main breaker branch. When the system is in the steady state operation, it has a power flow control function, which can adjust the branch power flow; when the system fails, the structure is equivalent to a hybrid DC circuit breaker for cutting off the fault current. A multi-port hybrid DC circuit breaker topology with power flow control function was established; the steady-state and transient operation mechanism were elaborated; and the economic characteristicswere analyzed. Finally, a four-terminal DC transmission system was built on the PSCAD simulation platform to verify the proposed topology, which has good performance in power flow control and fault removal.