Study On Partial Discharge Characteristics Of High Voltage Switchgear

With the rapid development of urban power grid, power supply mode and structure are becoming more and more complex, the security and reliability of power supply have increasingly been concerned. As one of the main power supply equipments in urban power grid,high voltage swithgear has the special function to the normal operation of power grids that cannot be substituted. The ring network is the common power supply mode in urban power grid, ring network refers to the ring distribution network,that is, the main-supply form a closed loop, power supply provid power to the ring main.,then distribute the power though high voltage swithgear. With the increasing demand for electricity in cities, ring network is becoming more and more complex, outgoing lines of ring network are increasing,sice outgoing lines are led out from the high voltage swithgear,so that one of the most important measures to ensure the safety and reliability of urban power is to ensure the safe and stable operation of high voltage switchgear.It is found that the partial discharge(Discharge Partial) is an electrical discharge in the insulation system, which occurs in the vicinity of the conductor(electrode), and can also be found in other parts. Due to the influence of electric, heat, water vapor, chemical and other factors in the operating environment,high voltage switch prone to insulation degradation, and thus lead to partial discharge. So the research on the characteristics of the high voltage switchgear is the necessary theoretical mean and method to protect the high voltage switchgear from the failure.In this paper,We focus on the research of the 10 kV high voltage switchgear(switch cabinet), emphatically and theoretically analyse the reasons of partial discharge in the switchgear, and the mechanism of partial discharge of the switchgear is comprehensive described in this paper;At the same time, Combined the practical experience, the types of partial discharge, the cause of the fault, the transmission characteristics, detection methods of the signal are explained in detail; In order to fully demonstrate that the phenomenon of partial discharge in the switchgear can improve the power supply reliability in power system, this paper introduces the methods and techniques used in the partial discharge monitoring of Shenzhen power grid, and analyzes the results of monitoring in recent years;In the end,We summarize the experience of partial discharge detection of switchgear and put forward the suggestions and attainment about improvement of partial discharge monitoring methods.