Analysis Of Magnetic Field And Temperature Field Characteristics Of UHV Oil-immersed Air Core Reactor

Due to its own structural characteristics and high current operating conditions,UHV air-core reactors are often accompanied by local overheating inside the reactor and large external magnetic field strength resulting in electromagnetic pollution.In this paper,a type of UHV oil-immersed air core reactor is studied.The calculation and analysis are carried out from both magnetic and thermal aspects.The magnetic field distribution of the reactor is analyzed firstly,then the hot spot distribution inside the reactor is proposed.Finally,the external space safety range and temperature field improvement are proposed.In the firet the Circuit-magnetic field coupling calculation model is established,calculates the magnetic field distribution of the reactor based on the finite element method,analyzes the internal magnetic field distribution law of the reactor in the first place,then gives the safety range of the external magnetic field of the reactor,and analyzes the effect of the base on the magnetic field distribution in actual constitution.Finally,the magnetothermal process of the reactor and the calculation method of the heat source are analyzed and calculated,which provides the basis for the subsequent temperature field calculation.Then the fluid-temperature field coupling simulation model of the reactor is established,and calculates the internal temperature distribution of the reactor and the flow velocity distribution of the insulating oil based on the finite element method and the experimental correlation method.The transient average temperature and maximum temperature distribution of the reactor coil and the insulating oil are analyzed,and the hot spot distribution of the insulating oil and the coil is analyzed at the maximum temperature.By analyzing the insulation oil shaft and radial flow velocity distribution of the reactor,the causes of the internal temperature unevenness of the reactor are analyzed,which provides the basis for the subsequent temperature field improvement.In the last place the viscosity parameter of the insulating oil is changed firstly to increase the overall flow velocity of the insulating oil and the temperature distribution of the insulating oil.Secondly,the transverse oil channel width between the top 10 layers of coils is increased to further in the purpose of increasing the flow rate of the insulating oil in the transverse oil passage.The maximum internal temperature of the reactor is reduced by 10 °C.And the overall distribution is more uniform.