电阻型超导限流器电阻特性测试及其建模方法研究

Research on Resistance Characteristics Test and Modeling Method of Resistance Superconducting Fault Current Limiter

电阻型超导限流器的限流能力取决于其电阻特性,因此需精确掌握电阻型超导限流器电阻变化特性及其在系统中工作特性。针对多端柔性直流输电工程用电阻型超导限流器,首先开展了电流冲击试验,获得其电阻值热积累量变化曲线;其次,提出了一种基于双指数函数的拟合方法拟合出电阻值与热积累量的数学表达式;进而,在PSCAD/EMTCD仿真软件中,基于电阻值与热积累量的数学表达式,建立了电阻型超导限流器的仿真模型;最后,对多端柔性直流输电系统开展短路故障仿真分析,仿真验证了电阻型超导限流器模型的正确性及其限流的有效性,达到了预期的限流水平。

The current limiting ability of a resistance superconducting current limiter depends on its resistance characteristics,so it is necessary to accurately grasp the resistance change characteristics of a resistance superconducting current limiter and its operating characteristics in the system.In this paper,a current impulse test is first carried out for the resistance superconducting current limiter for multi-terminal flexible DC transmission project to obtain its resistance-heating accumulation curve.Secondly,this paper proposes a fitting method based on the double exponential function to fit the mathematical expressions of the resistance value and the heat accumulation value.Furthermore,a simulation model of the resistance superconducting fault current limiter based on the mathematical expressions of resistance value and heat generation software is established in PSCAD/EMTCD.Finally,the short-circuit fault simulation analysis of the multi-terminal flexible DC transmission system was carried out.The simulation verifies the correctness of the resistance superconducting current limiter model and the effectiveness of its current limit,and reaches the expected current limit level.