Numerical Study on Transient State of Inductive Fault Current Limiter Based on Field-Circuit Coupling Method.

Wenrong Li,Derong Qiu,Jie Sheng,Junbo Cheng,Zhiyong Hong,Haosheng Ye

doi:10.3390/ma12172805

Abstract

As the capacity of the power grid continues to expand, high-level fault currents might be caused during a contingency, and the problem of short-circuit current over-limitation is imminent. The high-temperature superconducting (HTS) fault current limiter (FCL) is an effective method to solve this problem. In this paper, a transient numerical model for the process of limiting current in the inductive FCL is proposed. The model is based on the coupling of multiphysics finite element simulation and a circuit model. The voltage source is used as input, which can simulate the macroscopic characteristics in the process of limiting current, such as the voltage and current waveforms, and can also simulate microscopic characteristics, such as temperature, magnetic field, and electrodynamic force distribution. The short-circuit experimental data of an air core inductive superconducting fault current limiter (SFCL) prototype was compared with the simulation results to verify the reliability of the simulation.

Highlights

With the increasing power load and increased short-circuit capacity, the short-circuit current of the grid will continue to rise and will gradually approach the limits of the breaking capacity, which will greatly affect the stability of the power system and equipment
Among the current-limiting equipment, the superconducting fault current limiter (SFCL) is considered as one of the most effective methods to solve the problem of exceeding short-circuit current
In SFCL design, more attention should be paid to the large outward force acting on the primary winding, and it is necessary to enhance the structure; the heat dissipation problem should be considered, while ensuring that the support strength and the contact area between the winding and the liquid nitrogen are increased as much as possible

Summary

Introduction

With the increasing power load and increased short-circuit capacity, the short-circuit current of the grid will continue to rise and will gradually approach the limits of the breaking capacity, which will greatly affect the stability of the power system and equipment. Among the current-limiting equipment, the superconducting fault current limiter (SFCL) is considered as one of the most effective methods to solve the problem of exceeding short-circuit current. SFCLs can be divided into resistive, inductive, three-phase reactor, saturated iron core, and bridge types. The principle of resistive SFCL is the transition of the superconductor from superconducting to normal state. They are relatively simple in structure, but continuous losses during rated operation is unavoidable. The inductive SFCL omit the current leads, but in general use an iron core, which makes this SFCL relatively heavy and costly. The inductive SFCL has received more attention [2,3,4,5]

Methods

Discussion

Conclusion