| Being one of the most widely using high-voltage electrical equipment in power grid, the high-voltage disconnector’s operational reliability and operation life will influence the stable operation of power grid. Along with the fast development of technology, the demand of better performance of disconnector is higher because of the improving voltage classes, therefore the insulating problem and overheating are becoming more and more intractable. As a result, the most attention should be paid to electromagnetic environment control, anticorona structure design and the solving of overheating problem. The costly and inefficient traditional methods like empirical design and experimental method are hard to meet the fierce market competition and development needs of the grid, hence the using of finite element method(FEM) could provides the product design and optimization with new thinking and mean. The electric field analysis and temperature calculation of disconnector based on FEM can reduce the design cost, optimize the performance of the product, also put forward an effectively universal analysis mode.The paper was mainly divided in two parts which are electric field analysis with anticorona structure design and transient temperature analysis of GW16-550 outdoor high-voltage AC disconnector, offering reliable references and technical mean to disconnector design and optimization, exerting a positive effect on the performance improving of disconnector.The paper elaborated the background, significance and research status firstly, then discussed electromagnetism, heat transfer, mathematical theories which were used in electric field calculation and temperature calculation. To improve the efficiency of 3-D large-scale finite element calculation and lessen calculative burden, the paper simplified the model according to some principles by Solidworks and then used ANSYS APDL to iteratively solve the problems based on domain decomposition. The result of electric field calculation showed that, the fixed contact, the middle conductive part and the conductive base have to be controlled on account of high electric field intensity. In consequence, the paper designed anticorona structure respectively, first, the paper confirmed the shape of grading rings according to the geometric characteristics of each parts, and then calculated how the parameters of grading rings influence the electric field distribution, and found the optimal design which could controlled the electric field of disconnector surfaces to a ideal state. In temperature analysis, the paper firstly calculated the vortex field of disconnector to obtain the electric current density and heat generation which were the loads of next temperature calculation based on indirect coupling method. Subsequently, in consideration of the effects of contact resistance, the paper applied electrical contact theory and elastic mechanics principle synthetically to calculate the heat generation and heat flux of contact resistance of primary contact regions on by one, and make them to be boundary conditions in the final calculation. And the paper also analyzed the heat loss in natural convection environment. The consequence of temperature analysis demonstrated that the temperature rise of disconnector was in good condition, compared it with the actual test data, the result proved that this analysis was accurate. Aiming to analyze the performance of disconnector further, the paper calculated the heat stability of the contact region between moving contact and fixed contact where the temperature were highest. The result showed that the disconnector had a strong heat stability. After the discussing of how different clamping force of contact and contact area effect the temperature, the paper draw a conclusion that the increasing of clamping force of contact and contact area can effectively reduce the temperature rise in a certain range. The consequences of this paper have engineering practical value and guiding significance. |
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