Development of 66 kV/6.9 kV 2 MV A prototype HTS power transformer

Abstract We have developed the technology of the producing a HTS magnet for the power transformer. Three subjects have been mainly studied, high voltage technologies, large current and low AC loss technologies and sub-cooling system technologies to establish the technology of 66 kV/6.9 kV 10 MV A class HTS power transformer. In order to verify the validity of elemental technologies, such as high voltage technologies, large current and low AC loss technologies and sub-cooling system technologies, single-phase 2 MV A class 66 kV/6.9 kV prototype HTS transformer was manufactured and tested. In the load loss (AC loss) measurement, it was obtained that the measured value of 633 W was almost corresponding to the calculated value of 576 W at the rated operation of 2 MV A. Moreover, the breakdown was not found all voltage withstand test. These test results indicate that elemental technologies were established for the development of 66 kV/6.9 kV 10 MV A class HTS power transformer.