Electric And Temperature Field Simulation And Optimization Based On The Finite Element 252kV GIS Bus Bar

The electric field distribution of 252 kV GIS bus bar is calculated firstly using finite element method. The results show that, when input 1050 kV power lighting impulse voltage, the maximum electric field strength of GIS bus bar is 31kV/mm, it exceeds the industry standard’s value 24 kV /mm. Then the surface response method is introduced and integrated with finite element method, the 252 kV GIS bus electric field is optimized. The results show that, the electric field distribution of 252 kV GIS bus is more uniform, 1050 kV lighting impulse voltage withstand test reach the national standard, satisfy the design requirements and improve the reliability of the product operation.In order to research the heat dissipation of three-phase GIS bus box, indirect coupling method is used to calculate the temperature in the flow field. According the theory of fluid mechanics, the three-dimensional model of electromagnetic, flow and temperature field is established using the finite element method for three-phase GIS bus box. Various influence factors are analyzed which include the fluid velocity, the acceleration of gravity, conductivity temperature effect, eddy current loss, convection and radiation heat dissipation,and the temperature distribution of the bus tube is given. When the GIS bus is horizontal, the results show that the temperature distribution of cross-section is that, the temperature of Bus conductor and aluminum housing casing increases with the height decreasing and bilateral symmetry, the isothermal of SF6 gas present distributed. The temperature of middle bus bushing are higher than the both sides, the bus conductor temperature inside tube is the highest. The three-dimensional isothermal distribution calculated by Fluent is intuitively and has a strong engineering application value for miniaturization of bus tube design.The three-phase alternating input current of experiment is same with the finite element method simulation model, which has the effective value of 4000 A. Through the experiment and simulation numerical comparison, test temperature distribution is identical to the simulation of temperature rise distribution. The calculate bus temperature in the flow field causes error, but error in the permitted range. Combining the surface response method and finite element method, the bus bar is optimized. Then the optimized bus bar parameters are used in finite element method model, the obtained maximum temperature of bus accord with national standard.In order to test the allowable current of optimized three-phase 252 kV GIS bus, the three-phase alternating current of 4400 A effective value is input, and the experiment method is same as 4000 A. The temperature rising results show that, the maximum temperature of the bus exceeds the national standards when inputting 4400 A three-phase alternating current, temperature rise test is not passed. So the surface response method and finite element method are combined to optimize the structure of the bus. With the optimized bus bar structure parameters in finite element simulation, the results show that, the temperature of bus is reduced significantly with optimization method, bus withstand current is increased. By 252 kV GIS bus electric field and temperature field simulation analysis and structure optimization, the reliability of the product capacity is improved.