Performance Comparison of Typical Built-In UHF Sensors Used for GIS PD Detection

The UHF method is one of the most important partial discharge (PD) detection means for GIS, while sensor technique is the key factor of the UHF method. In comparison with external sensors, built-in sensors can achieve higher sensitivity. In this paper, two parameters were quoted to evaluate the performance of the sensor, which are He and S11. He refers to the PD detection sensitivity of sensor; S11 refers to the impedance matching property of the sensor. The paper firstly designed a simulation model of sensor performance evaluation, and then studied the performance differences of four typically used or researched built-in UHF sensors (i.e., disc-type, dipole-type, spiral-type and logarithmic-type) by simulation tools of CST. The conclusions of the paper can provide a reference for performance evaluation and type selection of UHF built-in sensor. Keywords: Gas Insulated Switchgear (GIS), Partial Discharge (PD), UHF, Sensor, Sensitivity