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Wind energy is seen as one of the main pillars of renewable energy. However, the intermittent nature of these sources still poses as a major challenge. Moreover, sensitivity to grid faults and response to load changes are also main concerns.Superconducting devices have been introduced to solve grid faults and energy storage problems associated with renewable energy sources. Nevertheless, the cost of superconducting materials was still a major drawback for their application in power grids.In this paper, a novel power electronics circuit is used to connect the superconducting magnetic energy storage (SMES) to a DC system based on a doubly fed induction generator wind turbine. The proposed system merges energy storage function and the fault current limiting function into one device which is referred to as SMES-FCL in this paper.The role played by the SMES-FCL is studied under various scenarios that may affect the whole system. The study of the system is carried in MATLAB/SIMULINK where the system is simulated in standalone and grid-connected modes. In the end, the proposed SMES-FCL control circuit is tested in a small-scale DC system experimentally.

With the high penetration of Renewable Energy Sources (RES) in power systems, the short-circuit levels have changed, creating the requirement for altering or upgrading the existing switchgear and protection schemes. In addition, the continuous increase in power (accounting both for generation and demand) has imposed, in some cases, the need for the reinforcement of existing power system assets such as feeders, transformers, and other substation equipment. To overcome these challenges, the development of superconducting devices with fault current limiting capabilities in power system applications has been proposed as a promising solution. This paper presents a power system fault analysis exercise in networks integrating Superconducting Cables (SCs). This studies utilized a validated model of SCs with second generation High Temperature Superconducting tapes (2G HTS tapes) and a parallel-connected copper stabilizer layer. The performance of the SCs during fault conditions has been tested in networks integrating both synchronous and converter-connected generation. During fault conditions, the utilization of the stabilizer layer provides an alternative path for transient fault currents, and therefore reduces heat generation and assists with the protection of the cable. The effect of the quenching phenomenon and the fault current limitation is analyzed from the perspective of both steady state and transient fault analysis. This paper also provides meaningful insights into SCs, with respect to fault current limiting features, and presents the challenges associated with the impact of SCs on power systems protection.

The increase in aircraft passengers and airfreight traffic has given rise to concerns about greenhouse gas emissions for traditional aircraft and the resulting damage to the environment. This has led several companies and organizations, including NASA, to set goals to enhance aircraft efficiency as well as reduce fuel burn, pollution, and noise for commercial aircraft. The most notable electric aircraft (EA) concept is the N3-X, which was developed by NASA to achieve environmental goals while maintaining the annual growth of the aviation industry. However, one of the main challenges that EA is facing is their overall weight. This paper proposes and explores an improved power system architecture for use in EA, based on the N3-X concept. The number of superconducting magnetic energy storage (SMES) and fault current limiter (FCL) devices required can be reduced by utilizing multifunctional superconducting devices that combine the functionalities of both a SMES and a FCL, thus reducing the weight and cost of the EA by eliminating a complete device. The proposed control technique offers greater flexibility in determining the appropriate size of coils to function as a FCL, based on the fault type. The proposed EA power system architecture including the SMES-FCL devices is modelled in Simulink/MATLAB to test the system performance under different failure scenarios.

This paper introduces a new scheme, which uses a multifunctional superconducting device that can be used as an energy storage and as a fault current limiter. It is denoted as a superconducting magnetic energy storage - fault current limiter (SMES-FCL) and is modeled as a number of pancakes. It is connected to a wind turbine power system via tertiary transformer and power converters. A complete control scheme is built to achieve effective power transfer between the superconducting coil and the power system during normal operation to smooth the wind turbine output power. The fault current limiting function is implemented using a new technique that inserts a few pancakes from the whole SMES coil into the main electrical system during the fault and isolates the remaining pancakes. The number of pancakes used to limit the fault is quenched and operates as a resistive fault current limiter. The whole system including the wind turbine, the SMES-FCL model, and the interface circuit are implemented using PSCAD/EMTDC computer package. Also, the control scheme of SMES-FCL is built based on a feedback current signal to enable its operation into the two modes.

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 superconducting fault current limiting transformer (SFCLT) as a superior alternative to normal power transformers. The transformer has superconducting windings and also provides fault current limiting capability to reduce high fault currents. The SFCLT is tested in two power system models: A 7 bus wind farm-based model simulated in PSCAD and on the 80 bus simplified Australian power system model simulated in real-Time digital simulator. Various conditions were studied to investigate the effectiveness of the fault current limiting transformer.

As the capacity of all-electric ships (AESs) increases dramatically, the sudden changes in the system load may lead to serious problems, such as voltage fluctuations of the ship power grid, increased fuel consumption, and environmental emissions. In order to reduce the effects of system load fluctuations on system efficiency, and to maintain the bus voltage, we propose a hybrid energy storage system (HESS) for use in AESs. The HESS consists of two elements: a battery for high energy density storage and a superconducting magnetic energy storage (SMES) for high power density storage. A dynamic droop control is used to control charge/discharge prioritization. Maneuvering and pulse loads are the main sources of the sudden changes in AESs. There are several types of pulse loads, including electric weapons. These types of loads need large amounts of energy and high electrical power, which makes the HESS a promising power source. Using Simulink/MATLAB, we built a model of the AES power grid integrated with an SMES/battery to show its effectiveness in improving the quality of the power grid.

Recently, superconducting fault current limiters (SFCLs) were proposed as an advanced device for fault ride through (FRT) capability of DFIG wind turbines without the need for controller and additional power electronic devices. However, for minimizing the cost of SFCL and maximizing the enhancement of FRT capability, it is needed to investigate the effect of SFCL parameters on FRT capability, which is the main goal of this paper. A detailed model of the resistive type SFCL has been implemented and integrated with a model of DFIG wind turbine using PSCAD/EMTDC software. SFCL model took into consideration the complete dynamic behavior of SFCL, including its three different regimes; superconducting regime, normal conducting regime, and recovery regime. The investigated parameters in this study are the limiting resistance, the critical current and the recovery time. To study the effect of each parameter in limiting the fault and enhancing the FRT capability, three phase fault was considered. The effect of each parameter is investigated considering the voltage profile, the active power generated and the current limitation at the generator terminals. Based on the obtained results, it is found that proper parameters of SFCL will achieve enhanced performance of the whole system during faults with minimizing the cost.

With increased penetration of wind energy as a renewable energy source, there is a need to keep wind turbines connected to the grid during different disturbances such as grid faults. In this paper, the use of superconducting fault current limiter (SFCL) is proposed to reduce fault current level at the stator side and improve the fault ride-through (FRT) capability of the system. To highlight the proposed technique, a doubly fed induction generator (DFIG) is considered as a wind-turbine generator, where the whole system is simulated using PSCAD/EMTDC software. Detailed simulation results are obtained with and without SFCL considering stator and rotor currents. In addition, the voltage profile at the generator terminals is analyzed. The effect of limiting resistance value is also investigated. The obtained results ensure that the SFCL is effective in decreasing the fault current. Moreover, both the voltage dip at the generator terminals and the reactive power consumption from the grid are decreased during the fault. The voltage dip characteristics are discussed in accordance with international grid codes for wind turbines.