GIS partial discharging detection system and method

The invention discloses a GIS partial discharging detection system which comprises a partial discharging ultrasonic subsystem and a partial discharging ultrahigh frequency subsystem. The partial discharging ultrasonic subsystem and the partial discharging ultrahigh frequency subsystem are connected with a computer. Further disclosed is a detection method. The detection method comprises the steps of (1) detecting a detected GIS, uploading the detection results to the computer, (2) allowing the computer to carry out data processing and identification on the results detected through the ultrasonic detection method, giving evidences according to the detection results to assign a function value to an elementary probability of a target, namely the assigned probability, (3) calculating evidence space of each GIS fault, and (4) confirming diagnosis results, namely diagnosis types according to diagnosis decisions. According to the GIS partial discharging detection system and method, the partial discharging faults of the GIS can be accurately found, accuracy for identifying the fault types can be improved, maintenance of the GIS is promoted to be developed from periodic maintenance and accident maintenance to state maintenance and reliability maintenance, and detection accuracy is improved.