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The resistivetype superconducting fault current limiter (R-SFCL) is simple in structure, near zero impedance at normal state and can be quickly triggered by the fault current. Thus, it is a possible solution to limit the fault current in the power grid. In this paper, we report the fabrication and test for an R-SFCL module The R-SFCL module consists of seven bifilar coils connected in parallel, which were wound with two parallel 2G tapes. A 5mm spacer was co-wound between adjacent turns to act as the highvoltage insulation. In the tests, we test the current distribution among the bifilar coils, and then simulated short-circuit tests were conducted on the module to obtain its performance under fault current surge. [ABSTRACT FROM AUTHOR]

Weak low voltage ride‐through (LVRT) ability and unstable output power are two major problems faced by the doubly‐fed induction generator (DFIG). To solve these two problems simultaneously, a commercially available fault current limiter‐battery energy storage system (FCL–BESS), which is suitable to be applied in a microgrid, is proposed in this study. During normal operation, the FCL–BESS stabilises the output power of DFIG by compensating the fluctuating component of DFIG output power with energy buffering capability provided by the battery energy storage system (BESS). On occurrence of a grid fault, the FCL–BESS enhances the LVRT ability of DFIG by inserting the fault current limiting inductor into the stator, which weakens the rotor back electromagnetic force voltage and limits the rotor overcurrent. The FCL–BESS also stabilises the DC‐link voltage by the BESS, which further strengthens the controllability of grid‐side converter and rotor‐side converter. Moreover, the FCL–BESS is able to help grid voltage recover fast and smoothly by providing power support to the grid. Experiments under different conditions have been carried out with a 2 kW prototype to evaluate the performance of the proposed FCL–BESS. Experimental results show that the FCL–BESS have much better performance than using single fault current limiter or BESS and can solve the two problems faced by the DFIG simultaneously and effectively. [ABSTRACT FROM AUTHOR]

A low-voltage ride-through (LVRT) strategy for a doubly fed induction generator (DFIG) with a switch-type fault current limiter (STFCL) is presented in this paper. The STFCL is composed of fault-current-limiting inductors, isolation transformers, a diode bridge, a semiconductor switch, a snubber capacitor, and a fault energy absorption bypass. The presented STFCL can insert fault-current-limiting inductors in series with the stator branches on occurrence of a grid fault, which can limit the rotor overcurrent and weaken the rotor back electromagnetic force voltage simultaneously. The safety and controllability of the rotor side converter can thus be guaranteed. The STFCL can also absorb the excessive energy stored in the stator during LVRT with the fault energy absorption bypass so as to prevent the semiconductor devices from overvoltage. The feasibility of the proposed approach is validated by simulation studies on a typical 1.5-MW wind-turbine-driven DFIG system. The validity of the proposed approach is further verified by the experimental results on a 2-kW DFIG prototype. [ABSTRACT FROM PUBLISHER]