Reactor Type Fault Current Limiter Research Articles

LVRT capability enhancement of DFIG-based wind farms by using capacitive DC reactor-type fault current limiter

Low-voltage ride-through (LVRT) is the core of grid code requirements for grid connection of wind farms (WFs). This paper presents a capacitive DC reactor-type fault current limiter (CDRFCL) for LVRT capability enhancement of doubly-fed induction generator (DFIG)-based WFs. The CDRFCL is based on the conventional DC reactor-type fault current limiter (DRFCL), which is modified to overcome its limitations of operation and is adapted with the WF environment. To check the effectiveness of the proposed CDRFCL, its performance is compared with the series dynamic braking resistor (SDBR). The WF is modeled with equivalent aggregated DFIG. The PSCAD/EMTDC simulation results show that the CDRFCL is an effective solution for enhancement of LVRT capability and limitation of fault current contribution (FCC) of WFs.

Novel high performance DC reactor type fault current limiter

This paper presents a novel structure for DC reactor type fault current limiter (DRFCL), which can suppress the fault current in distribution networks. The proposed DRFCL is composed of a DC reactor, a bridge rectifier, and anti-paralleled IGBTs power electronic (PE) switch. The DC reactor contains main and supplementary windings. The main winding has a high inductance and acts as a DC reactor. The supplementary winding is used as a control means for fast FCL operation. The fast response allows the cost, weight and volume of the DC reactor to be reduced. The proposed DRFCL reduces the overvoltages on the devices and it has lower number of components, therefore, it can be economic. Analytical solutions, to describe the performance of the proposed DRFCL are presented and the proposed model is simulated via MATLAB software. Finally, a one-phase prototype structure is built and experimental results are studied to show the capability of the proposed DRFCL.

Single-DC Reactor-Type Transient Limiter for Reducing Three-Phase Power Capacitor Switching Transients

This paper presents a new application of the single-dc reactor-type fault current limiter to suppress the three-phase low-voltage capacitor switching transients. The proposed limiter is composed of a three-phase coupling transformer, a three-phase bridge rectifier, a dc reactor, and a dc-bias voltage source. The dc reactor is connected in the three-phase coupling transformer's secondary winding and can automatically provide high impedance at the instant of energization, thus restraining the energizing transients of the three-phase capacitor. In the steady state, the bias voltage causes all rectifier diodes to conduct simultaneously, and the limiter freewheels. Therefore, the voltage across the coupling transformer's secondary side is nearly zero, and the transformer's primary side acts as a short circuit. The limiter will not result in a voltage rise at the capacitor's terminals or a distortion of the capacitor's current waveform in the steady state. Due to the freewheeling effect in the limiter, no transient overvoltage appears across the switching device at the instant of de-energization. Analytical equations to describe the performance of the system have been developed. Finally, a 2.7-kVAR three-phase capacitor is used for demonstration, and simulation and experimental results are carried out to verify the feasibility of the proposed limiter.

System studies and DC reactor type fault current limiter in distribution grid

System studies and DC reactor type fault current limiter in distribution grid

Non‐superconducting fault current limiters

AbstractThis paper proposes the use of non‐superconducting DC reactor type fault current limiter (NSFCL) instead of superconducting fault current limiters (SFCLs) which has high cost and technology. Proposed FCL consists of three similar sets, each including a diode bridge and a single non‐superconducting DC reactor. The device is connected in series with distribution line and it has almost no effect on the normal system operation. It is not necessary to use a control circuit and it has a simple and cheap power circuit. Design characteristics, analytical analysis and overall transient and steady‐state performance of NSFCL in normal and fault conditions are presented in this paper. The comparison between experimental and simulation results indicate good agreements. The results confirm that the power loss of NSFCL is a very small percentage of distribution line power. Also, the system current and load voltage distortions due to using NSFCL is explained and simulated. Copyright © 2008 John Wiley & Sons, Ltd.

Preliminary experiments on saturated DC reactor type fault current limiter

Preliminary experiments have been performed on our proposed saturated DC reactor type superconducting fault current limiter (SFCL). The proposed SFCL is similar to a DC reactor type but an additional control winding is used. The DC bias current in the control winding saturates the core. The B-H curve of a magnetic circuit shows that low inductance value can be achieved in saturated region and high value in unsaturated region. The inductance of the saturated reactor depends on type of magnetic material, core size, number of turns and biasing conditions. The advantage of this type of SFCL over the existing DC reactor type is that, it shows low inductance value at normal operation and high value during fault time. On the other hand, the present DC reactor type SFCL shows a fixed value of inductance both in normal and fault time. In our experiment, we observed the inductance behavior of the saturated reactor by changing the control current. In order to make the work simple and convenient we have chosen a ferrite core. The experimental results are presented in this paper.

Test of DC reactor type fault current limiter using SMES magnet for optimal design

This paper deals with the operational characteristics of a three-phase DC reactor type fault current limiter (FCL) at a short-circuit test. This type FCL consists of transformers,. diodes, and a superconducting coil. In this paper, a superconducting coil, low-Tc SMES magnet, is made of Nb-Ti and the power system of the experimental circuit is 400 V/7 A class. This is a preliminary step to develop its faculties for applications to high voltage transmission line. As the results of the experiment, the values are referred to the limitation rate about 77% and 90% when the turns ratio of transformer was 1 and 2, respectively.

Single DC reactor type fault current limiter for 6.6 kV power system

We propose a single DC reactor type fault current limiter. This fault current limiter is for a three-phase power system, employing only one superconducting coil that is connected with the secondary windings of transformers through a diode-bridge. In this composition, a DC reactor type fault current limiter using a high temperature superconducting coil takes advantage of coil inductance and does not require a superconducting coil normal transition. This paper presents the most suitable case of a single DC reactor type fault current limiter for a 6.6 kV power system and compares it with a three DC reactors type fault current limiter.

Application of single DC reactor type fault current limiter as a power source

This paper presents an application of single DC reactor type fault current limiter (FCL) with a gate turnoff (GTO) thyristor bridge as an emergency power source. A DC reactor type FCL stores electrical energy in a superconducting coil at a steady state. When a power transmission stops due to line faults, the FCL supplies stored energy to the load. This conception can be realized by operating the GTO thyristor bridge as an inverter. On the other hand, the function of fault current limitation is possible by keeping all GTO thyristors turned-on. The proposed FCL is numerically tested in a three-phase distribution system.

Performance of DC reactor type fault current limiter using high temperature superconducting coil

The purpose of this work is to study a DC reactor type fault current limiter (FCL) using high temperature superconducting (HTS) coil which is connected with the secondary winding of a transformer through a diode bridge. The high temperature superconductors provide the advantages of a higher temperature operation and they are preferably applied to the DC reactor type fault current limiters, where a superconducting coil can be operated at both low voltage and DC current. The authors propose a DC reactor type three-phase FCL incorporating only one HTS coil and present its test result. A three-phase FCL for 6.6 kV-2000 A requires one HTS coil of 2.9 MJ.

Recovery time of superconducting non-inductive reactor type fault current limiter

A superconducting fault current limiting device for electric power systems has been investigated to determine its feasibility. A noninductive reactor type fault current limiter has been constructed using a metal superconductor. Two bifilar wound solenoids were connected in antiparallel or antiseries. On each connection, a fault current limiting test was performed by suddenly short-circuiting a resistive load. The recovery (normal-to-superconductive state transition) time after the current limiting mode has been studied using a small-scale model of a fault current limiter for an LV power distribution line. The results reveal that the current limiter could be operated under a repetitive fault current accident which was removed within a few cycles of the limiting mode. The recovery time is a function of the dissipated energy under current limiting mode. Test results are presented.

Preliminary study on non-inductive reactor type fault current limiter

A superconducting fault current limiting device for electric power systems has been investigatedto find out its feasibility. Non-inductive reactor type fault current limiter has been constructed using metal superconductor. Two wires that have different critical currents were bifilar wound. Two type of connections have been tested. In the first, the pair of trigger and limiter solenoids were connected antiparallel, whereas in the second, they were connected antiseries. On each connection, the fault current limiting test was performed by short-circuiting a resistive load suddenly. After opening the load circuit a few seconds, the reclosing of the circuit was performed successfully. Then recovery time was investigated. The series type NRSFCL is selected for next research and development.

Tests of oxacetylene welded joints in steel plates

A superconducting fault current limiting device for electric power systems has been investigatedto find out its feasibility. Non-inductive reactor type fault current limiter has been constructed using metal superconductor. Two wires that have different critical currents were bifilar wound. Two type of connections have been tested. In the first, the pair of trigger and limiter solenoids were connected antiparallel, whereas in the second, they were connected antiseries. On each connection, the fault current limiting test was performed by short-circuiting a resistive load suddenly. After opening the load circuit a few seconds, the reclosing of the circuit was performed successfully. Then recovery time was investigated. The series type NRSFCL is selected for next research and development.