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To meet the requirement of grid codes about low voltage ride through (LVRT) of wind turbine generators (WTGs), a cooperative control scheme of resistor-type superconducting fault current limiter (SFCL) and superconducting magnetic energy storage (SMES) for improving the LVRT capability and transient stability of permanent magnetic synchronous generator (PMSG) based WTGs is investigated in this paper. In the proposed scheme, the SFCL is utilized to increase the output active power from grid side converter (GSC) to half of the pre-fault value, and the other half is absorbed by SMES so as to reduce its maximum energy storage capacity. In addition, a SFCL's resistance estimation method is introduced by using the grid-side voltage phasor relation that is established based on the grid voltage vector oriented control of GSC. Finally, a PMSG-based WTG integrated with the SMES and SFCL is built in PSCAD/EMTDC. Performance evaluations and comparisons demonstrate the advantages of the proposed scheme in improving the transient stability of PMSG and reducing the capital cost for superconducting devices. [ABSTRACT FROM AUTHOR]

• A cost-effective SFCL-based low-voltage ride-through (LVRT) scheme is proposed for wind turbine. • Cooperative operation of SFCL device and modified converters controls is presented for improving SFCL performance. • Provide a cost-effective solution to eliminatiing impact of grid voltage magnitude on LVRT enhancement of resistive-SFCL device. • Superconducting tape usage and capital cost of SFCL can be visibly reduced. • Preferable comprehensive performance with wider adaptability and better cost-effectiveness than traditional control-based scheme and SFCL device-based scheme. Series single-resistor based scheme (SSRBS) can achieve a favorable low-voltage ride-through (LVRT) enhancement, also has the advantages of low costs and complexity. Its basic idea is to increase the terminal voltage of wind turbine generator (WTG) during grid faults by inserting a series single-resistor into the grid-side circuit. However, traditional SSRBSs cannot tackle different grid voltage sag events due to the constant resistance of the inserted resistor. Besides, as a device-based scheme, the SSRBSs have weak cost-effectiveness especially, utilizing the superconducting fault current limiter (SFCL). To solve these problems, this paper proposes a cost-effective LVRT scheme by cooperating a resistive-type SFCL and two modified controls. In the cooperative scheme, a surplus power dissipating mechanism based on SFCL is designed, which provides a novel way for SFCL to improve LVRT capability. Moreover, modified reactive power control for WTG is proposed to ensure that SFCL can dissipate constant surplus power irrespective of grid voltage magnitude and to provide reactive power support. Additionally, another modified WTG control is proposed for assisting with the SFCL to dissipate surplus power, which reduces the tape usage and energy-loss of SFCL, thus improving cost-effectiveness. Several cases demonstrate the feasibility and superiority of this scheme. [ABSTRACT FROM AUTHOR]