适用于中压柔直配电网的电容辅助型断路器  

CAPACITOR-ASSISTED CIRCUIT BREAKER FOR MEDIUM-VOLTAGE FLEXIBLE DC DISTRIBUTION NETWORKS

作　　者：戴志辉 刘珊珊 李毅然 Dai Zhihui;Liu Shanshan;Li Yiran(State Key Laboratory Alternate Electrical Power System with Renewable Energy Sources(NCEPU),Baoding 071003,China)

机构地区：[1]新能源电力系统国家重点实验室(华北电力大学),保定071003

出　　处：《太阳能学报》2024年第9期179-187,共9页Acta Energiae Solaris Sinica

基　　金：国家自然科学基金(51877084)。

摘　　要：针对柔直配电网短路故障电流大且无电流自然过零点导致故障隔离困难的问题,提出一种基于电容辅助关断的混合式断路器。该断路器设置了两级限流结构,低阻限流模块用以故障初期快速限流、实现故障电流转移,高阻限流模块用以保证断路器的可靠关断,在保护启动过程及保护识别过程中均能起到限流作用。相比传统方法,电容辅助关断模块可以限制故障初期电流的发展,大大降低故障电流峰值与主断开关的关断电流,且其在正常工作时对主电路影响较小。最后,通过PSCAD/EMTDC建立六端直流配电网进行仿真分析,结果表明,所提断路器能够较大幅度限制故障电流,且同时满足经济性和实用性。Aiming at the difficulty of fault isolation caused by large short-circuit fault current and no natural zero crossing of current in flexible direct distribution network,a hybrid capacitor-assisted circuit breaker is proposed.The circuit breaker possesses a two-stage current limiting structure.The low-resistance current limiting module is used to quickly limit the fault current in the initial stage and achieve the fault-current transfer.The high-resistance current limiting module is used to ensure the effective isolation.It can play a current limiting role before the fault line is identified.Compared with the typical method,the capacitor-assisted module can limit the development of the initial fault current and greatly reduce the peak current value of the main-breaker branch,and it has minimum impact on the main branch during the normal operation.Finally,a six-terminal DC distribution network is established by PSCAD/EMTDC for simulation analysis,and results show that the proposed scheme can significantly limit the fault current and meet both the economy and practicality.

关 键 词：故障限流器 电容 短路电流 柔性直流配电网 直流断路器 

分 类 号：TM773[电气工程—电力系统及自动化]