Development of smart diagnosis system for 800 kV gas -insulated switchgear

In this paper, we roughly describe the principles and structures for the sensor applications and diagnostic algorithm with together networking and monitoring system for 800 kV GIS. Firstly, we describe the detailed specifications and the results of research, and then present the experimental results of the diagnostic algorithm for 800 kV GIS. For the diagnosis of mechanical operation, we used auxiliary CT (current transformer) and auxiliary contacts as a sensor. It was performed experiments in general and extreme conditions to establish the standard values that can be evaluated the condition of mechanical operation, and then was obtained the standard values to prevent the faults. The technique that monitors the leakage current of a zinc-oxide lightning arrester is described with the results of field test. Methods are also described to detect partial discharge and ground fault location, as well as to monitor gas pressure.