After understanding the basic concepts of partial discharge detection in high-voltage switchgear, the following is an inventory of the discharge detection methods of high-voltage switchgear.

1. Ultrasonic testing method

Ultrasonic detection method is to judge the position and distance of partial discharge by listening to the sound, and realize the monitoring of electrical partial discharge. It is one of the methods in the field of preventive maintenance. Ultrasonic detection method suffers little electrical interference, and it is widely used in partial discharge positioning.

Two, chemical detection method

The chemical detection method means that when a partial discharge occurs in a transformer, various insulating materials will be decomposed and destroyed, and new products will be produced. By detecting the composition and concentration of the products, the state of the partial discharge can be judged. At present, chemical detection methods have been widely used in online fault diagnosis of transformers. The type of fault is different, the degree of the fault is also different, and the composition and concentration of the gas are also different. The pattern recognition system established by this can realize the automatic recognition of the fault. But until now, there is still no unified judgment standard. Because it is more sensitive to early detection of latent failures, but it cannot reflect sudden failures.

3. UHF partial discharge detection

There are deficiencies or defects in traditional detection methods, and then a new detection method-ultra-high frequency detection has emerged. The ultra-high frequency (300-3000MHZ) electrical signal generated by the partial discharge of the transformer realizes the detection and positioning of the partial insulation discharge of the power transformer, and realizes the anti-interference.