| During the operation of the switchgear,insulation breakdown and overheating will directly affect the normal use of the mechanical system,endanger the safety of the national grid,and even cause accidents,which can endanger people’s lives in severe cases.The problems of insulation strength,heat dissipation and temperature rise control of vacuum switchgear have become important research topics in this field.Therefore,research on the insulation and temperature rise control of the vacuum switchgear is of great practical significance for improving the safety and reliability of the operation of the switchgear.The main contents of the paper include:Taking the armored mobile 20 kV vacuum switchgear as the research object,the 3D modeling of the switchgear is carried out using Solid Works software.In order to study the insulation characteristics of the vacuum switchgear,the three-dimensional model diagram was imported into the ANSYS simulation software,and the electric field simulation study was carried out on the busbar room and the circuit breaker room of the switchgear.The three-dimensional model of the busbar chamber and the circuit breaker chamber is simplified,and boundary conditions are set.Through simulation calculation,the maximum electric field strength of the busbar chamber and the circuit breaker chamber is greater than the critical breakdown electric field strength of air.Therefore,this article discusses the structure of the busbar,mainly by optimizing the thickness of the busbar and the radius of curvature at the corners.The optimized results satisfy that the maximum electric field strength is less than the critical breakdown field strength of air insulation.Based on ANSYS simulation software,this paper conducts a temperature field simulation study on the switchgear busbar room and the circuit breaker room according to the totally enclosed situation and the forced ventilation cooling system scheme,in order to solve the temperature rise and heat dissipation problems of the switchgear in the application.In the closed condition,when the loading current is 3150 A,the maximum temperature rise value meets the basic requirements of the temperature rise of the switchgear;when the load current is 4000 A,the room temperature rise of the bus room and the circuit breaker rises substantially,and the temperature rise of the bus bar is slightly close The temperature rise limit is 50 K,and the circuit breaker’s room temperature rise far exceeds the temperature rise limit of 35 K.After adopting forced ventilation and heat dissipation measures,when the 4000 A high current is loaded,the busbar room and the circuit breaker room both meet the temperature rise limit requirements of the switchgear equipment.Finally,this paper analyzes and compares the influence of different currents and different wind speeds on the maximum temperature rise of the switchgear.Through the simulation study of the temperature field of the high-current vacuum switchgear,the relationship between the temperature rise of the high-current switchgear and different currents and different wind speeds is analyzed. |
