Thermal Characteristics Analysis Of The Steering Gear Control Circuit Board Under Electric-thermal Conditions

With the continuous development of electronic packaging technology,the power density of electronic packaging structural components have continued to increase,and the operating temperature of the chip has also increased,resulting in a sharp increase in the internal structural heat flow density during the operation of the packaging circuit.The thermal and mechanical performance requirements of the structure,especially the solder joints,continue to rise,so the thermal stress of the structure has also become one of the important factors affecting the stability and reliability of electronic packaging devices.In this paper,the control circuit of a missile-mounted servo is taken as the research object.The research is based on the analysis of the response of the control circuit under different operating conditions under electric-thermal conditions.The heat transfer theory and finite element analysis method are used to carry out the research.The effect of self-heating of the control circuit under different operating conditions is studied,and then the control circuit and transmission components are assembled in the box.Based on the self-heating of the control circuit,the response of the control circuit is analyzed in combination with the ambient temperature,which lays the theoretical and analytical basis for further temperature control experiments.The specific research content is as follows:(1)The domestic and foreign research statuses of the thermal characteristics of electronic components,board-level structures,and box structures are introduced,and the corresponding theories of electricity and heat and the finite element analysis methods are described.Combined with the corresponding literature,taking the insulated gate bipolar transistor(IGBT)model as an example,the thermal characteristics of different operating conditions are simulated and calculated.The response results of the cloud diagram and numerical values are compared with the literature results.Structural analysis provides theoretical support and technical support;(2)A three-dimensional finite element model of the servo control circuit board is established,and a constant power load is loaded.The dangerous position is studied from the response angles of temperature,stress,strain,and displacement.At the same time,the Joule generated by the chip pin current is compared and analyzed The influence of heat on the overall research results;loading cyclic power loads,exploring and researching dangerous locations from response angles such as temperature,stress strain,displacement,etc.,and comparing and analyzing the effects of different powers on response results;(3)An overall three-dimensional finite element model is established that integrates the control board of the steering gear and the ball screw of the transmission component in a box with a thermal insulation layer.The influence of the steering gear control circuit;simulate the harsh environment in which the steering gear is in service,and simulate whether the two box models with heat insulation layer are placed under the gradient temperature load and compare and analyze the effect of heat insulation layer.Response to explore the effect of the insulation layer on the control circuit inside the protective box;(4)By comparing and analyzing the responses of different materials with thermal insulation layers,and selecting appropriate insulation materials by comprehensively considering various factors;by comparing and analyzing the responses of different thickness insulation layers,choosing appropriate thermal insulations by comprehensively considering various factors Layer thickness.