Electrical Insulation Design of 13.2 kV/630 A Bifilar Winding Type HTS Fault Current Limiter

In this study, electrical insulation design for the development of 13.2 kV/630 A bifilar winding type high temperature superconducting (HTS) fault current limiter (FCL) with YBCO coated conductor (CC) wire was conducted. At first, operating conditions of the temperature and the pressure were determined considering the effects of bubble suppression and breakdown withstand voltage in quench state. The electrical insulation design for HTS coil was performed based on electric field calculation under normal and quench states. Furthermore, new concept of cryostat which is beneficial to the sub-cooling and the electrical insulation was proposed. Finally, two high voltage lead designs were evaluated taking into account the insulation environment of the HTS FCL and the new cryostat design.