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CG Global R&D is developing a resistive-type superconducting fault current limiter (SFCL) under the Ministry of Power, National Perspective Plan for R&D in Indian Power Sector. A resistive-type 440-V 800-A single-phase SFCL is developed using YBCO tape in stage I of the project, and an 11-kV 1250-A three-phase SFCL will be developed in stage II. The 440-V 800-A SFCL is assembled with seven parallel modules. Each module has series-connected YBCO tapes to accommodate the design length. The SFCL is tested at 77 K for continuous current of few hours, fault currents at low voltage, and fault currents at 440 V up to 100 ms (5 cycles). The evaluated data will be used to develop an 11-kV 1250-A three-phase SFCL in stage II. [ABSTRACT FROM PUBLISHER]

This paper describes thermal modeling, using computational fluid dynamics (CFD), to predict the temperature rise of a high-voltage SF6 gas circuit breaker during a heat-run test. In electrical equipment, maximum temperature rise in various components is limited by their material properties and, hence, the heat-run test forms part of type test. A methodology to predict the temperature rise at the design stage is developed using ANSYS-CFX and found to be beneficial to reduce the number of heat-run tests during the product development process. The developed methodology has been implemented on a 72.5-kV SF6 gas circuit breaker and validated with the experimental temperature rise results of the existing design at two current ratings: 1000 A and 2000 A. The methodology was further used to predict thermal performance of the breaker at a higher current rating of 3150 A. The prediction helped to understand temperature rise in various components and hot-spot locations. Various design modifications were then tested virtually to evaluate the temperature rise. Thereafter, the final modified design where the temperature rise of all the components was within the permissible limits and which also satisfied other constraints of manufacturing feasibility and cost was fabricated and physically tested. Good agreement is found between the CFD and experimental results. [ABSTRACT FROM PUBLISHER]