Detection of Partial Discharges Occurring in Propulsion Coils of Superconducting Maglev Systems from a Test Bogie Running at High Speed Using a Radio Interferometer System with a Vector-Antenna

Abstract

A large number of ground coils are used in superconducting magnetic levitation (Maglev) systems; therefore, it has been considered that condition monitoring systems for the ground coils are mounted on Maglev trains. We have been studying radio sensing techniques to detect partial discharges (PD) occurring in propulsion coils. In this study, a radio interferometer system with a vector-antenna was mounted on a test bogie, which can be run at the speed of 200 km/h by remote control. The vector-antenna composed of vertical and horizontal dipole-antennas was set to the center of the antenna-array of the radio interferometer system. A set of mock-ups of the propulsion coil and the levitation-guidance coil was set on the side of the test track of which length is 500 m. The propulsion coil has multiple holes penetrating through insulation to the inner conductor for attaching a needle-electrode; one or some of the holes can be voluntarily chosen to generate PDs. Experimental results showed that the propulsion coil with a PD source set behind the levitation-guidance coil could be located from the test bogie running at the speeds of 198.5 km/h and 212.3 km/h.