摘要
机械式直流断路器(DCCB)是直流开断的主流方案之一。然而,远海风电构网型柔性直流系统对机械式DCCB提出轻型化、紧凑化的要求。性能分析表明,目前的机械式DCCB存在预充电系统耐压要求高、预充电容的容量高、预充能量损失率高、换流时间长、小电流熄弧不稳定等问题。为此,提出一种谐振型机械式DCCB(RM-DCCB),通过控制晶闸管的导通时刻并利用其过零自关断特性,逐次在换流支路注入能量,产生了幅值递增的谐振电流。研究了RM-DCCB的换流特性、数学模型和参数设计方法。通过PSCAD/EMTDC仿真验证了RM-DCCB的开断可行性和参数设计的正确性。研究表明,RM-DCCB是一种具备综合技术优势的换流新方法。
Mechanical DC circuit breaker(DCCB)is one of the mainstream solutions for DC interruption.However,the flexible DC system constructed by the offshore wind power puts forward the requirements of lightness and compactness for the mechanical DCCB.The performance analysis shows that current mechanical DCCB has some problems,such as high withstand voltage requirements of precharging system,high capacitance of pre-charging capacitor,high loss rate of pre-charging energy,long commutation time,unstable arc extinguishing at small current and so on.Therefore,a resonant mechanical DC circuit breaker(RM-DCCB)is proposed.By controlling the turn-on time of thyristor and using its zero-crossing self-turn-off characteristics,energy is successively injected into the commutation path,and the resonant current with increasing amplitude is generated.The commutation characteristics,mathematical model and parameter design method of RM-DCCB are studied.Through PSCAD/EMTDC simulation,the interruption feasibility of RM-DCCB and the correctness of parameter design are verified.The research shows that RM-DCCB is a new commutation method with comprehensive technical advantages.
作者
李斌
李鹏宇
温伟杰
刘海金
Li Bin;Li Pengyu;Wen Weijie;Liu Haijin(Key Laboratory of the Ministry of Education on Smart Power Grids Tianjin University,Tianjin 300072 China;Electric Power Research Institute of State Grid Shanxi Electric Power Company,Taiyuan 030000 China)
出处
《电工技术学报》
EI
CSCD
北大核心
2022年第9期2139-2149,共11页
Transactions of China Electrotechnical Society
基金
国家自然科学基金(52025071,51907141)
天津市自然科学基金(20JCQNJC01300)资助项目。
关键词
机械式直流断路器
注入能量
谐振电流
换流特性
参数设计方法
Mechanical DC circuit breaker
injected energy
resonant current
commutation characteristics
parameter design method
