The so-called “partial discharge” refers to a discharge in which only a part of the insulation system discharges without forming a penetrating discharge channel under the action of an electric field. The main reason for partial discharge is that when the dielectric is not uniform, the electric field strength of each area of ??the insulator is not uniform. In some areas, the electric field strength reaches the breakdown field strength and discharge occurs, while other areas still maintain the characteristics of insulation. The insulation structure of large-scale electrical equipment is relatively complex, the materials used are various, and the electric field distribution of the entire insulation system is very uneven. Due to imperfect design or manufacturing process, there are air gaps in the insulation system, or the insulation is damp during long-term operation, and moisture is decomposed under the action of an electric field to generate gas and form bubbles. Because the dielectric constant of air is smaller than that of insulating materials, even if the insulating material is under the action of an electric field that is not too high, the field strength of the air gap bubbles will be very high, and partial discharge will occur when the field strength reaches a certain value. . In addition, there are defects in the insulation or various impurities mixed in, or there are some poor electrical connections in the insulation structure, which will cause the local electric field to concentrate, and the solid insulation surface discharge and floating potential may occur in the place where the electric field is concentrated.

? ? ? ? ? ? ? ? ? ? ? ? ? ?? ?HV Hipot GD-610C?Remote?Ultrasonic?Partial?Discharge?Detector

The partial discharge inspection instrument independently developed and produced by HV Hipot adopts precision high-frequency ultrasonic sensors to collect and select the characteristic sound waves emitted by the partial discharge of power equipment of 110kV and below, and realize the positioning and judgment of defects through filtering and comparison. And the collected real-time data can be synchronized to the cloud, which can truly realize front-end detection and rear-view analysis.

It is suitable for detecting partial discharge of various types of knife switches, switch cabinets, insulators, transformers, arresters, cable joints, hardware and other non-sealed electrical equipment in substations or on transmission and distribution lines.