Service background:
In the process of GIS operation, there will be external mechanical faults such as the infirmness of contact of the isolation switch, the infirmness of the conductor and the plug insulator, the loosening of the shield, and the loosening of the GIS grounding bolt.
System principle:
The basic principle: GIS conductor flows through periodic current, generates electromotive force, and electromotive force acts on GIS device. Once the mechanical state is in trouble, the mechanical vibration signal will be abnormal.
Abnormal performance: signal amplitude increases, spectrum complexity increases, and the percentage of fundamental frequency increases.
Detection method: mechanical vibration signal detection to achieve mechanical state detection.
The contact defects were made on a 252kV entity GIS by the isolation switch. A large current test was carried out on the contact of the contact, and the vibration test was carried out, and the test results were analyzed.
