모의배전계통에 두 트리거 전류레벨을 이용한 초전도한류기의 전류제한 특성 분석

고석철,한태희,Ko, Seok-Cheol,Han, Tae-Hee 한국전기전자재료학회 2013 전기전자재료학회논문지 Vol.26 No.2

When the accident occurred in power distribution system, it needs to control efficiently the fault current according to the fault angle and location. The flux-lock type superconducting fault current limiters (SFCL) can quickly limit when the short circuit accidents occurred and be made the resistance after the fault current. The flux-lock type SFCL has a single triggering element, detects and limits the fault current at the same time regardless of the size of the fault current. However, it has a disadvantage that broken the superconductor element. If the flux-lock type SFCL has separated structure of the triggering element and the limiting element, when large fault current occurs, it can reduce the burden of power and control fault current to adjust impedance. In this paper, this system is composed by triggering element and limiting element to analyze operation of limiting current. When the fault current occurs, we analyzed the limiting and operating current characteristics of the two triggering current level, and the compensation characteristics of bus-voltage sag according to the fault angle and location.

변압기에 적용된 초전도소자의 한류특성과 고장전류 특성

김원배 ( Won Bae Kim ),임인규 ( In Gyu Im ),최혜원 ( Hye Won Choi ) 조선대학교 공학기술연구원 2013 공학기술논문지 Vol.6 No.2

In this paper, in the event of line-to-line of line-to-ground, superconductor device fuse in the transformer to limit the fault current for prevent fault range expansion and characteristics of fault current were analyzed according transformer turn-ratio. second and third winding of 3-phase transformer, each phase superconducting fault current limiter and fault current limiter was applied. in normal operation, current flows in the superconducting element of second winding and in event of the fault, the initial fault current was limited. FCL of third winding was limit the fault current after the initial fault current limited. at this time, characteristics of limiting current followed by Single-phase transformer turn-ratio and characteristics of fault current by voltage characteristics was analyzed in 3-phase transformer. At result, increasing the turn-ratio of the second winding, fault current limiter rate was increased. when 3-phase transformer applied to superconducting element, voltage increases but limit rate was no change. because superconducting fault current limiter of second winding was limited initial fault current.

고장발생 위치에 따른 두 개의 동작전류를 갖는 자속구속형 초전도한류기의 전류제한특성

고석철(Seok-Cheol Ko),임성훈(Sung-Hun Lim) 한국조명·전기설비학회 2016 조명·전기설비학회논문지 Vol.30 No.6

In this paper, we proposed a flux-lock type superconducting fault current limiter (SFCL) with two operational currents, which could detect and limit the fault current according to the amplitude of the fault current. The proposed flux-lock type SFCL is largely composed of two parts. One is two magnetically coupled coils wound in parallel on iron core and the other is two parallel connected high-Tc superconducting (HTSC) modules through an inserting resistance (Rx). The short-circuit tests were performed to analyze the current limiting operation and the power burden characteristics according to the fault location. Through the analysis on the experimental results, the current limiting operation was confirmed to be effectively performed by the quench generation in either two superconducting elements for a higher fault current or one superconducting element for a lower fault current directly after the fault occurrence. The total power burden in the superconducting modules comprising the SFCL was showed to be more reduced in the fault location with the larger fault current than in the fault location with the lower fault current.

이중퀜치를 이용한 삼상변압기형 초전도한류기의 삼상지락 고장 종류에 따른 고장전류 제한 특성 분석

이신원,한태희,임성훈,Shin-Won Lee,Tae-Hee Han,Sung-Hun Lim 한국전기전자재료학회 2023 전기전자재료학회논문지 Vol.36 No.6

The fault current limiting characteristics of three-phase transformer type superconducting fault current limiter (SFCL), which consisted of three-phase primary and secondary windings wound on E-I iron core, one high-TC superconducting (HTSC) element connected with the secondary winding of one phase and another HTSC element connected in parallel with other two secondary windings of two phases, were analyzed. Unlike other three-phase transformer type SFCLs with three HTSC elements, three-phase transformer type SFCL using double quench has the merit to perform fault current limiting operation for three-phase ground faults with two HTSC elements. To verify its proper three-phase ground fault current limiting operation, three-phase ground faults such as single-line ground, double-line ground and triple-line ground faults were generated in three-phase simulated power system installed with three-phase transformer type SFCL using double quench. From analysis of its fault current limiting characteristics based on tested results, three-phase transformer type SFCL using double quench was shown to be effectively operated for all three-phase ground faults.

Operational Characteristics of the FCL Using the Mechanical Contact in the Power System

Byung ?Ik Jung(정병익),Hyo-Sang Choi(최효상) 대한전기학회 2016 전기학회논문지 Vol.65 No.5

These days, SFCLs are being developed in order to limit fault current. However, the superconducting elements that limit the fault current have such problems as capacity increase and require auxiliary devices including cooling device. If devices that comprise the current power network can withstand fault current for at least one cycle, it is possible to limit the fault current with current limiting elements by bypassing it on the fault line. In this study, the fault current limiter was configured with current transformer, vacuum interrupter, and current limiting element. Through the experience, it was confirmed that the fault current was limited within one cycle. The superconducting element, as a current limiting element, limited the fault current by 80 % within one cycle from fault occurrence, and the passive element limited it more than 95 %. Also, through the comparison between resistance curve and power consumption curve, it was confirmed that the current limiting element using a passive element was more stable than the superconducting element that required capacity increase and other auxiliary devices. It was considered that the FCL proposed in this study could limit fault current stably within one cycle from fault occurrence by using the existing power technologies such as fault current detection and solenoid valve operating circuit.

고속 인터럽터를 적용한 한류기의 전류제한요소에 따른 특성

임인규(In-Gyu Im),최효상(Hyo-Sang Choi),정병익(Byung-Ik Jung) 대한전기학회 2012 전기학회논문지 Vol.61 No.11

With the development in industry, power demand has increased rapidly. As consumption of power has increased, Demand for new power line and electric capacity has risen. However, in the event of fault, problems occur in extending the range of fault coverage and increasing fault current. In these reasons, protection devise is recognized as the prevention of an accident and fault current. This paper dealt with minimizing fault propagation and limiting fault current by adjusting fault current limiter (FCL) with fast interrupter. At this point, we compared and analyzed characteristics between non-inductive resistance and fault current which is limited by superconducting units. In normal state of the power system, power was supplied to the load, but when fault occurred, the interrupter was operated as CT which detected the over-current. Its operation made the limitation of fault current through a FCL. We concluded that the limiter using superconducting units was more efficient with the increase of power voltage. Superconducting fault current limiter with the fast interrupter prevented the spread of a fault, and improved reliability of power system.

사고전류 제한형 고온 초전도케이블의 한류부 특성평가

김태민,홍공현,한병성,두호익,Kim, Tae-Min,Hong, Gong-Hyun,Han, Byung-Sung,Du, Ho-Ik 한국전기전자재료학회 2015 전기전자재료학회논문지 Vol.28 No.3

Inside the existing superconducting cables, the superconducting wire carries a loss-free current, and the cable former (the stranded copper wire) bypasses the fault current to prevent damage and loss of the superconducting cable when the fault current is applied. The fault-current-limiting-type superconducting cable proposed in this paper usually carries a steady current; but in a fault state, the cable generates self-resistance that makes the fault current lower than a certain width. That is, the superconducting cable that transmitted only a low voltage and a large capacity power repetitively limits the fault current, as does a superconducting current limiter. To complete this structure, it is essential to investigate the mutual resistance relationship between the superconducting wires after applying a fault current. Therefore, in this paper, one kinds of superconducting wires (a wire without a stabilization layer) were connected parallel 4 tapes, respectively; and after applying a fault current, the current, voltage, resistance and thermal stability of the HTS thin-film wires were examined.

Study on Initial Current-Limiting Performance of the Resistive-Type SFCL Element According to the Electrical Coupling Condition With Cores and Coils

Ho-Ik Du,Byoung-Sung Han,Gong-Hyun Hong Institute of Electrical and Electronics Engineers 2016 IEEE transactions on applied superconductivity Vol.26 No.4

<P>This paper was conducted to widen the use of the YBCO-coated conductor's superconducting current-limiting element under the electrical coupling condition with cores and coils. Using cores and coils, diverse winding directions and turn ratios were available, and the initial operating performance of the superconducting current-limiting element could be improved. In this paper, three kinds of YBCO-coated conductors with stabilization layers that had different specific resistivity values were used to fabricate superconducting current-limiting elements, and an electrical coupling condition, which did not produce resistance in the normal operating condition when it was combined with the superconducting current-limiting elements, was presented. After the superconducting current-limiting elements were combined with the electrical coupling condition, an overcurrent was applied, and the initial operation performance was examined. The initial operation performance indicators were the current-limiting rate, response time, and steep slope of the initial current-limiting curve. The current-limiting rate was excellent when the specific resistivity of the superconducting current-limiting element was high and when it was combined with the electrical coupling condition to increase the equivalent impedance. However, when the specific resistivity of the YBCO-coated conductors to the superconducting current-limiting elements was too low, the electrical coupling condition did not work properly. The response time and steep slope of the current-limiting curve characteristics showed that they did not depend on the specific resistivity of the superconducting current-limiting elements when the equivalent impedance of the electrical coupling condition was higher than the resistance of the superconducting current-limiting elements.</P>

전력 계통 신뢰도 개선을 위한 대표적인 한류기 유형 및 적용 효과 분석

고윤석,이우철 한국전자통신학회 2023 한국전자통신학회 논문지 Vol.18 No.6

A rapid increase in power capacity in a power system can seriously reduce system reliability by causing the fault capacity to exceed the breaking capacity of circuit breaker. Fault current limiter is a practical and effective way to improve reliability by limiting fault capacity to the breaking capacity level. In this study, in order to help develop an application methodology when applying fault current limiters to power systems, first the topology and operating principles of each type of fault current limiters was reviewed, and the main advantages and disadvantages was compared. Next, to verify the effect of applying fault current limiter to the power system, the power system in which the fault current limiter was introduced was modeled. Finally, after simulating a three-phase short-circuit fault using EMTP-RV, the effect of application was verified by comparing the fault current before and after application of the fault current limiter and confirming that the fault current was reduced by the fault current limiter.

Current-limiting and Recovery Characteristics of a Flux-lock-type SFCL with Two Adjustable Operational Currents

고석철,한태희,임성훈 한국물리학회 2014 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.65 No.2

In this research, the current-limiting and recovery characteristics of a flux-lock-type superconductingfault current limiter (SFCL) with two adjustable operational currents were analyzed. Theflux-lock-type SFCL with two adjustable operational currents, which consists of two magneticallycoupledcoils, two high-TC superconducting (HTSC) modules connected in parallel, and an insertingresistance connected in series with one of the two HTSC modules, can limit the fault current withtwo operational currents by quench generation in either one HTSC module for a lower fault currentor two HTSC modules for a higher fault current directly after the fault occurrence. To verify thecurrent-limiting operation of this type SFCL, we constructed the simulated power distribution systemprotected by the SFCL, and we executed the short-circuit tests in the fault locations with boththe lower and the higher fault currents. Through an analysis of the experimental results, effectivecurrent limiting operations of the flux-lock-type SFCL could be confirmed.