The research of thermal design for vehicle controller based on simulation

• A thermal design simulation model for sealed vehicle controller is setup and its accuracy is verified through experimental results. Based on the model, multiple impact factors to the optimal thermal performance from the design perspective could be investigated.
• A four-layer board with two inner layers, 1.6 mm board thickness and more than 50% coverage percentage is recommended for a better thermal design performance.
• Component placement is an important affecting factor for the board's temperature rise. Multiple trials for components location can be performed in order to achieve an optimal thermal design effect.

Thermal design of vehicle controller is an important element in the total design process, because of the impact of temperature on performance and reliability. A thermally well-designed electrical component applied in a thermally poor designed controller, will still result in a poor total design. And it is important that thermal design on controller should be included as early as possible in the overall design process. In this paper, a thermal simulation model of the sealed vehicle controller has been setup. The temperature prediction validity of this model is verified by experiment measurement. Based on this model, multiple influencing factors on the maximum temperature of the print circuit board (PCB) are analyzed. The simulation analysis results illustrate that increased internal layers and copper coverage percentage can significantly reduce the board's temperature, and selecting high heat conductivity PCB substrate material is another method to achieve the same goal, while the height of controller case and thickness of the board has no significant effect. Components placement is another important factor that affects the board's temperature-rise. The temperature of a well component layout board can be reduced dramatically compared to a poor layout board.