饱和铁心型超导限流器

饱和铁心型超导限流器具有限流功能可靠、输电稳态损耗小、限流恢复时间短等优异特性。根据其工作原理,一方面,用于直流励磁的超导绕组自身不承受短路电流冲击,这避免了其它类型超导限流器中由于超导绕组失超所带来的诸多技术难题;另一方面,其主体电抗器可以借鉴成熟的铁心电抗器技术。因此,饱和铁心型超导限流器的以其优异的性能特性和成熟的工程实现技术,成为迄今为止人们研究的各类超导限流器中的最具实用价值的一种。在电网容量不断扩大,智能化水平不断提高的今天,饱和铁心型超导限流器有非常广阔的应用前景。文中将叙述饱和铁心型超导限流器的基本原理、结构形式、功能特性,并对已在云南普吉变电站挂网运行的35kV/90MVA超导限流器进行简要介绍。

Saturated iron - core superconducting fault current limiter

Saturated iron-core superconducting fault current limiters have some superior performance features,such as very low operation loss at normal power transmission,high impedance at fault current limiting,immediately reacting,and fast recovering.Thinks to its working mechanism,there is no risk of quench to the superconductor coil on the impact of the fault current,so complex mechanical,electrical and thermal protection measures can be avoided.The complicity to deal with a quench of superconductor might be a severe technical barrier for other types of superconducting fault current limiters.In addition,the reactor of the device is mainly composed by iron cores and copper coils,which can be built with the technology for conventional transformers or reactors.For these reasons,this kind of superconducting fault current limiters is considered the most practically viable device in industrial applications.In this paper,the fundamental principles,the structures and the performance features of saturated iron core SFCLs are introduced.The specifications,testing results,and the operational status of a 35kV/90MVA superconducting fault current limiter that has been running for about 3 years at Puji substation,are also presented.