The existing CSC-HVDC system must compensate for reactive power because of the using thyristors as power conversion switching elements. It is impossible to control active power and reactive power independently. The VSC-HVDC system is receiving attention for solving such a problem. In VSC-HVDC, the study of fault current interruption is necessary to improve the stability and reliability. In...
Recently, the research and development of superconducting cables have been actively advanced all over the world. Particularly in RTRI, the research of superconducting cables for the railway electrification system (DC) is advancing. If the superconducting cables are used as a feeder of the railway system, the voltage decay could be significantly reduced. Therefore, DC High Temperature...
This paper presents a superconductivity fault current limiter(SFCL) DC interrupting system in wind power generation gird. SFCL DC interrupting system is comprised of SFCL and DC circuit breaker. When faults occurs, SFCL operates firstly to limit the maximum fault current and the residual fault current will be vanished by opening operation of dc circuit breaker secondly. To ensure the correct...
This paper presents a superconducting coil-type DC Fault Current Limiter(FCL). It has a combination structure of superconducting coils and DC circuit breaker in series. The superconducting coils operate as current limiting element. It was quenched when the fault is generated and limits the maximum fault current. Mechanical DC circuit breaker operates as interrupting element. It cut-offs the...
In this paper, the transformer type superconducting fault current limiters (SFCLs) with common connection point between two secondary windings, which was similar structure to the previously suggested transformer type SFCL with two triggering levels, were proposed and their current limiting characteristics were compared. The suggested transformer type SFCLs consist of the primary winding and...
For the flux-coupling-type superconducting fault current limiter (SFCL) which is composed of coupling transformer (CT), superconducting component (SC) and controlled switch, it can be regarded as a typical application of magnet technology. As the flux-coupling-type SFCL offers many technical advantages, such as higher flexibility, better controllability and lower operation loss, this paper...
The current limiting and recovery characteristics of a trigger type superconducting fault current limiter (SFCL) using double quench, which consists of a power switch, two separated current limiting reactors and two superconducting (SC) elements, were analyzed. The suggested trigger type SFCL can perform two fault current limiting operations (single quench operation and double quench...
In this paper, the transformer type superconducting fault current limiter (SFCL) with additional secondary winding, which could limit the fault current through twice quench operations, was suggested. The suggested SFCL includes one primary winding, two non-isolated secondary windings wound on the same iron core, and two high-TC superconducting (HTSC) elements connected with each secondary...
Saturated iron-core superconducting fault current limiter is a kind of promising device for short-circuit current limiting. During normal operation, large ampere-turns created with DC in the secondary superconducting HTS coil drive the core into saturation. This lowers impedance of the copper coil in the primary AC side near to that of an air - core coil. During a fault, a large fault current...
The flux-coupling type superconducting fault current limiter (FC-SFCL) is suggested to suppress the short-circuit current in the dc line of VSC-HVDC system. The FC-SFCL could generate larger inductance and smaller resistance at the beginning of current limiting process, but show smaller reactance and very large resistance at the end. One FC-SFCL module with two branches is designed and tested....
Superconducting fault current limiters (SFCLs) are considered as one of the most technical potentials to limit fault current levels, for that they can suppress fault currents without adding impedance to the circuit during normal operation. In this paper, a small-scale test prototype of the flux-coupling type SFCL (FC-SFCL) is designed and fabricated, and a series of experimental tests are...
Next generation electric power systems require higher capacity, efficiency, and stability to meet the demands of increasingly complicated grid systems. High-temperature superconductors (HTS) provide unique solutions to stringent operating requirements, including the ability to protect electric power apparatus and systems from large currents that can develop during a fault. The extensive...
Superconducting devices have emerged in many applications during the last few decades. They offer many advantages including high efficiency, compact size, and superior performance. However, the main drawback of these devices is the high cost. An option to reduce the high cost and improve the cost-benefit ratio is to integrate two functions into one device. This paper presents the...
High Voltage Direct Current (HVDC) transmission systems using Voltage-Source Converters (VSC) are widely recognized as having significant potential for long distance high power delivery, particularly for offshore wind farm connections. The US Navy has also proposed a Medium Voltage DC (MVDC) distribution architecture for the all-electric shipboard power systems. NASA is also evaluating...
With the development of DC power supply systems, breaking capacity of circuit breakers has been increasingly unable to meet the growing requirements for DC system short-circuit current level. To ensure the safety of the systems, a fault current limiter must be used in series with circuit breakers. The properties of superconducting fault current limiters such as fast reaction rate, simple...
Superconducting fault current limiter (SFCL) is an efficient way to solve the short-circuit problems in modern power system. A novel Flux-coupling type SFCL (FC-SFCL) based on disconnecting coupling windings for current-limiting has been proposed.For its low steady impedance at normal state and high limiting one after fault, FC-SFCL is considered as a potential scheme to limit short-current....
Superconducting fault current limiter (SFCL) can not only reduce the capacity of the circuit breaker but also lower the cost of line construction, it become more and more popular for the application in a high-voltage transmission line. A novel superconducting fault current limiter with bias magnetic flux is proposed by using a reactor with two symmetrical split copper windings and a...
No-insulation (NI) coil made of 2G HTS tape has many advantages over insulated coil that it has higher engineering current density and self-protection characteristic. While there are few researches of NI coil in AC power application due the charging/discharging delay of NI coil. In this paper, we apply NI coil into inductive superconducting fault current limiter (iSFCL) as the secondary...
The development of 500 kV saturated iron core superconductive fault current limiter(SFCL) is in progress. The magnet consists of 88 high temperature superconducting(HTS) double pancake coils with an inner diameter of 1940 mm and outer diameter of 2040 mm. Double pancake coil plays an important role in 500 kV SFCL, the structure and winding process have great influence on current carrying...
