Study on Reliability Evaluation Technology for Isolation Switch Operation in GIS

At present, the research method based on the reliability of the isolating switch inside the GIS mainly includes using SF6 gas density relay for monitoring SF6 pressure in the preventive test, infrared imaging temperature for measurement, using the signal collection for determining its position indicator and isolating switch state, using the high voltage and circuit resistance for testing its insulation performance and the contact of conductive circuit. Yet, pressure test and the loop resistance can be used for insulation test only in offline mode, especially the above monitoring method cannot fully reflect comprehensive objective status inside the isolating switch. When the interior of the isolating switch does not reach the designated position, or poor contact, the above methods cannot effectively detect the reliability of the internal isolation switch. This paper starts from the current problems in GIS isolation switch state monitoring, expounds the current situation of GIS isolation switch state, and conducts research from the following aspects: 1, Analysis on GIS isolating switch equipment failure. Analysis of the current grid GIS isolating switch fault type and the cause of the problem. According to the aspect of design, installation process and installation environment, operation condition analysis isolating switch does not reach the designated position defects existing in the development and fault formation, from the perspectives of movement mechanism and physics mechanics analysis with isolating switch does not reach the designated position fault instance. 2. Research on GIS isolation switch reliability diagnosis method. According to the testing principle of disconnecting switch, the testing software and sensor are improved. Through programming to modify the test software parameters for isolating switch test software platform, research and development is suitable for various turn arm bracket and fix connection transition device. And by means of experimental debugging and measuring the GIS isolating switch, isolating switch points, closing time,, contact stroke and secondary points from feed motion transmitting time. 3. Application of GIS isolation switch action characteristic state monitoring. This paper analyzes the function of GIS isolation switch action characteristic test in establishing GIS equipment new characteristic database, power failure condition monitoring and fault diagnosis, and analyzes the application of state monitoring and fault diagnosis method through testing data volume.