Locating partial discharge generated in PLG type-ground coil for superconducting Maglev using radio interferometer system

Superconducting Magnetically Levitated Vehicle (Maglev) system needs a number of ground coils installed on the guideway, which corresponds to the rails of a conventional railway. In order to reduce the construction cost by reducing the number of ground coils, a combined propulsion, levitation and guidance (PLG) type-ground coil (PLG coil) has been developed. Because the main insulating material of PLG coil is epoxy resin, it is required to develop the insulation diagnosis technique for the ground coils installed along the entire length of the guideway. We apply the radio interferometer system, which has been originally designed, to locate partial discharge (PD) generated in the PLG-coil. The radio interferometer system can locate PD by calculating the time difference of arrival of EM waves emitted from PD. This paper describes the results of PD location by using the radio interferometer system set at three positions in turn and the effect of position.