1 Abstract--One of the viable solutions for handling the fault current levels in power systems is the use of fault current limiters (FCL). Superconducting fault current limiter (SFCL) is widely accepted as the preferable solution for limitation of fault current level.Matrix-type FCLs show almost good performance in practice and therefore it is necessary to work on their theoretical basis and their modeling. Verification of proposed theoretical models can give a basis for extending studies of SFCLs in digital computers.In this paper, at first, theoretical model of Bi2212 SFCL has been introduced, then MFCL concept and the test circuit have been explained and then simulation results have been presented and from its comparison with results of experimental setup, the proposed theoretical model has been verified. It can help researchers to study what is in their mind in digital computers. Index Terms--Bi2212, E-J characteristics,EMTP-RV,fast quenching,fault current level, fault current limiter (FCL), high- temperature superconductor, Matrix-type FCL (MFCL), resistive SFCL I. INTRODUCTION UE to the increased interconnection of networks and the growth in the use of distributed and renewable energy resources and new power plants, fault current levels in power system continue to rise; therefore it is necessary to upgrade existing substation equipment or use fault current limiters so that the existing circuit breakers can still operate without any upgrade. Superconducting fault current limiter (SFCL) is widely accepted as the preferable solution from both the economic and technical points of view [1]-[3]. For SFCL application the superconducting (SC) materials must meet have (1) low AC loss in normal operation (2) high mechanical strength, and (3) good thermal stability. Due to high cooling costs of Low temperature superconductors (LTS), High Temperature Superconductors (HTS) could attract the attentions and commercialize, but some of their weak points must be compensated by changing their architecture, due to ceramic nature of the HTS, conductors with sufficiently low AC losses for arbitrary directions of the Amin Mohseni is with High Voltage Institute of University of Tehran, North Kargar, Amirabad, High Voltage Lab (e- mail:a.mohseni@ece.ut.ac.ir). SaeedMohajerYami is with High Voltage Institute of University of Tehran,North Kargar, Amirabad, High Voltage Lab(e- mail:s.mohajer@ece.ut.ac.ir). Amir Abbas ShayeganiAkmal is with High Voltage Institute of University of Tehran as an assistant Professor, North Kargar, Amirabad, High Voltage Lab(e-mail: shayegani@ut.ac.ir). magnetic field have not been demonstrated. AC losses are usually minimized by decreasing the conductor dimensions transverse to the local magnetic field.Most HTS are fabricated in tapes or plates or tubes.The rather brittle HTS is mechanically stabilized by supporting metallic or insulating substrate. With application of a normal conducting “electrical bypass”, HTS can thermally be stabilized. Theoretical model of current limiting performance of HTS materials are almost well documented [4]. Among HTS there are three major material systems under intensive research for SFCL application: i.e. Bi2223 wires, YBCO films, and Bi2212 bulk. This paper has been focused on bulk Bi2212. The matrix-type SFCL (MFCL), which consists of a trigger part and a current limiting part, has been regarded as one of the best SFCLs in terms of improving quench characteristics of the superconducting elements [5], [6]. MFCLs show almost good performance in practice and therefore it is necessary to work on its theoretical basis and application of theory of physics of superconductor to experimental studies. Verification of theoretical models can give a basis for extending studies of SFCLs in digital computers. In this paper, at first, theoretical model of Bi2212 SFCL has been introduced, then MFCL concept and the test circuit have been explained and after that simulation results have been presented and from its comparison with results of experimental setup, the theoretical model would verify and finally conclusion has been made. II. THEORETICAL MODEL OF BI2212 SFCL A. Basic Principle of SFCL A superconductor resistivity varies in different condition and generally it can be divided into three regions namely, the “superconducting state” (ρ=0), the “flux-flow state” (ρ=ρ(j)), and the “normal conducting state” (ρ=ρ(T)) as shown in Fig. 1,[7]. When superconductor is directly connected in series to the line (resistive SFCL) and at the normal condition, it is practically invisible for the power system; but in case of a fault, increasing of the current above critical current of superconductor, forces the superconductor into the flux-flow state. The rapidly increasing temperature and resistance can drive superconductor into “normal conducting state” and it will limit the fault current to an acceptable value. By varying the architecture of SFCL, different limitation behaviors can be realized [7].The transient behavior of the superconducting device can be described by the E-J characteristic and heating- effect due to the resistive power dissipation in the flux flow and normal state. Modeling of Matrix Fault Current Limiter and Its Verification A. Mohseni, S. MohajerYami, and A.A. ShayeganiAkmal D