Research On Fault Current Limiter Based On Fast Switching Technology And Its Energy Saving Application

With the rapid development of China’s power grid,the scale of the power grid is expanding,the system capacity and load increases,short-circuit current exceeding the standard has become one of the outstanding problems.In some economically developed areas of China,short-circuit current has far exceeded the current breaking capacity of circuit breakers.Short circuit current will seriously endanger the safety of power systems,but also bring down the power quality,voltage drop and other issues,therefore,the problem of short-circuit current exceeded must be addressed and resolved.The fault current limiter(FCL)is very effective to solve the problem of over-current and voltage drop in short-circuit fault,so it is necessary to study the fault current limiter Key technologies.In this paper,a new type of fault current limiter based on fast switching technology is proposed based on the summary of various types of fault current limiters and traditional current limiting reactors at home and abroad,and the related research is also carried out.The working principle and topological structure of the fast-switching fault current limiter are analyzed and analyzed.The current limiting effect of the fast-switching fault current limiter is simulated and analyzed by using MATLAB/Simulink.The position of the fault current limiter is analyzed according to its working principle and characteristics.Analysis and optimization.Secondly,this paper studies the key technology of fast switching fault current limiter.Aiming at the difficulty of vacuum arc extinguishing and the difficulty of rapid current transfer in the process of breaking current limiter,the current zero-crossing scheme is proposed to solve the above problems and improve the breaking capacity and service life of fast switch.In order to meet the demand of fast breaking current,a new kind of electromagnetic repulsion switch structure with fast eddy current is studied,and its working principle and calculation method of electromagnetic force are introduced.The problem of current transfer overvoltage in the current zero-crossing scheme is analyzed by MATLAB/Simulink and the solution is put forward.In this paper,the energy-saving effect of the fast-switching fault current limiter is analyzed in detail and its economic benefit is analyzed,which proves the energy-saving effect and economy of the fast-switching fault current limiter.Finally,this paper analyzes the influence of the fast-switching fault current limiter to the power system.This paper analyzes the influence on the transient stability of the system and the breaking capacity of the high-voltage circuit breaker,and puts forward some suggestions for the negative influence of the fault current limiter.