High Voltage Discharge Causes And Prevention Research Of Substation Equipment

With the rapid development of China’s UHV power grid and construction projects, a large number of new large-capacity substations are put into use. And power users to supply reliability and power quality requirements increase, especially as more and more large capacity transformers and new GIS equipment put into operation. Once the failure happens is bound affect the safe operation of the grid, causing accident and major national economic losses. The demand of reliable operation of the power system in China, also contributed the development of the analysis and prevention technology in substations. Before a device fails, the equipment operating status remotely assess, latent failures of equipment at the beginning discover, routine maintenance of the equipment in the substation process can be targeted, rapid troubleshooting, providing strong support for the reliable operation of the substation.Based on an actual operation of the substation equipment process analysis found that the main fault occurs once type equipment is insulated substation failure, but under normal circumstances, causes insulation failure is partial discharge, therefore we are in accordance with the principle of equipment line detection. First, as a transformer substation primary equipment main line detection method is the pulse detection, but its drawback is obvious that detection susceptible to interference, detection efficiency is not high, a need to explore the use of detection methods and equipment without electrical contact. Now the transformer primary means of online testing is UHF and ultrasonic detection assay, these two detection methods can detect joint, improve the effectiveness of detection accuracy and detection, fault type judging and fault location.Intelligent Substation on-line monitoring technology mainly includes the following aspects:inductive sensor to collect a fault signal device, a sensor device truly reflect the current operating situation is the basis for on-line monitoring; research substation electromagnetic interference inside the complex environment of communications also new demands. Equipment manufacturers processing equipment during operation and quality of the process of moisture, aging and so may affect normal operation and insulation of equipment, partial discharge is one of multiple problems. Thus, expand the substation primary equipment partial discharge line detection is of great significance, for control equipment, insulation status, as soon as possible accidents in the bud with outstanding results.This paper discusses the type and characteristics of common fault of primary electric equipment, fault causes and hazards produced by the faults, pointing out the necessity and urgency of online monitoring for substations.In this paper, discharge failure types of primary electric equipment such as power transformers, GIS, switchgear, surge arresters are classified to identify law of faults, causes and avoidance measures, and seek appropriate technologies for substation environment in many on-line monitoring technologies.Then, for power transformers, GIS, switchgear and other various devices of different types of partial discharge, developed the corresponding partial discharge diagnosis, type of analysis, fault location and a series of comprehensive technology for the development of modern substation online monitoring.