Research On Condensation Mechanism And Protective Measures Of 10kV Ring Main Unit

As an important device used to switch,control and protect electrical equipment,Ring Main Unit(RMU)plays an important role in the power generation,transmission,distribution and conversion process of the power system.In recent years,the outdoor equipment safety accidents caused by the condensation phenomenon have occurred constantly in different regions of China,which seriously threaten the safe operation of outdoor electrical equipment.Especially in the circumstances of high temperature and humidity or low temperature and high humidity,the internal RMU is prone to condensation,resulting in corrosion of parts and degradation of electrical equipment insulation property,and even leading to insulation surface discharge and accident.Therefore,the research on condensation mechanism and protective measures of 10 kV RMU is conducted,the main works are as follows:Firstly,the condensation mechanism of RMU is researched.A condensation test system of RMU is set up in artificial climate chamber,and the condensation images at different time are shot,based on the improved morphological method,the water droplets are extracted by MATLAB software,and the condensation development process is analyzed;the condensation formation time under different temperature and humidity inside the cabinet and the temperature difference between inside and outside the cabinet is recorded,and the temperature of the inner wall of the cabinet is measured when condensation is unformed to research the effects of temperature,humidity and dew point temperature on condensation phenomenon;the influencing factors of condensation time are analyzed in theory;Secondly,the experimental research on ventilation effect of RMU is studied.Based on the reformed RMU,bubble wrap with good air tightness is used to seal the RMU,and the condensation test is conducted under cable duct stiffness or ventilation and RMU's shell stiffness,half ventilation or full ventilation conditions,and the condensation development law and anti-condensation effect under ventilation condition are studied;Finally,the anti-condensation experimental research on secondary chamber is carried out.Secondary chamber anti-condensation measures comparison test under ventilation,installing heat insulation,DC fan and heater conditions are conducted to verify the anti-condensation effect of different common measures,and the inner surface roughness of the second chamber is changed by using the method of spraying quartz to analysis the influence of different roughness on condensation.