Research On Precise Finite Element Modeling Method Of Electronic Equipment Structure

Electronic equipment will subjected to vibration and shock load during transportation、assemblyand work. If the response magnitude is too large, it will result in pin fracture、solder joints fracture、vibration of reed relay and components fracture. In order to ensure high reliability of the structure, wehave to analyze the dynamic response using finite element method.In this article, we used sensitivity analysis method and response surface method to identify thephysic parameters. In order to estimate the range of the physic parameters, we introduced themodeling of uncertainty into the modeling of PCB to estimate the range of the physic parameters.Then we used local composite modeling method to model the PCB which is attached withcomponents like resistance、capacitance、relay. The screw used to connect the PCB and frame, thecontact of the PCB and frame was non-linear. In order to simplify the model, we had to use the linearmethod instead of non-linear. We used four modeling method and compared them with each other, thebush element method was good. The components had six rigid modes due to the headers, we usedbush element to model it and identify the spring stiffness based on modal tests result. Electronicequipment often subjected to identification of random vibration level load and work load, we took aelectronic equipment used in aerospace as an example to analyze the transient response and randomvibration response of the structure. Then we used static strength reliability and fatigue reliability toevaluate it.It shows that, the modeling methods introduced above fit the accuracy requirements well. Theresult of static strength reliability and fatigue reliability analysis shows that the structure is safe.