Design And High-Temperature Insulation Characteristics Analysis Of Wall Bushing For High-Temperature Solid Electrical Heat Storage Devices

With the rapid development of China's new energy industry,the participation of hightemperature solid electrical heat storage devices in new energy consumption can not only absorb excess new energy power generation,solve the "three wastes" dilemma,but also replace coalfired boilers for heating with new energy power generation,effectively reducing greenhouse gas emissions.Therefore,research on the electrical insulation and thermal insulation principle of high temperature solid electrical heat storage devices wall bushings is necessary to ensure the high temperature insulation safety of the bushings,further improve the voltage level and heat storage capacity of high-temperature solid electrical heat storage devices,and improve the consumption of new energy such as wind energy.The wall bushing technology of the high-temperature solid electrical heat storage devices is relatively new,and the bushing's use environment is harsh.Although there are design schemes for commercial use in China,the existing wall bushing of the high-temperature solid electrical heat storage device has a simple insulation structure and a single type,it is difficult to adapt to higher voltages.Therefore,in this thesis,the wall bushings that can withstand high voltages above 66 kV and high temperatures above 800 ? are taken as the research object to carry out theoretical research and structural design of electrical insulation and thermal insulation.The high-temperature insulation characteristics of wall bushing of high-temperature solid electrical heat storage devices are analyzed through multi-physics coupling field simulation of temperature field,force field and electric field.This thesis designs a new type of high-temperature solid electrical heat storage devices wall bushing,and focuses on the design principle and calculation method of the electrical insulation and thermal insulation structure of the bushing according to the use environment of the wall bushing of the high-temperature solid electrical heat storage device.In the design of the electrical insulation structure,the dry capacitor structure is used to improve the insulation performance.The equal insulation design method is used to calculate the internal insulation parameters.In the design of thermal insulation structure,the vacuum layer and the heat blocking ring are used to achieve thermal insulation.The RC thermal network is used to calculate the thermal insulation structural parameters.Based on the calculation of the bushing design,the electrical insulation and thermal insulation performance analysis indexes of the bushing are proposed according to the bushing design principles.Then through COMSOL finite element calculation,the safety of the designed bushing is verified,and the effects of temperature distribution,deformation and relative permittivity on the high-temperature insulation performance of the bushing were studied based on the results of multi-physics simulations.Through examples and simulation verification,it proves that the structure of the wall bushing of the high-temperature solid electrical heat storage device described in this thesis is reasonable and effective.Through the analysis of high-temperature insulation characteristics,the optimization direction of the bushing structure is proposed,which can provide a basis for the standard design and optimization of similar products.