Power supply thermal analysis

Abstract

The article provides an analysis of heat removal from power elements in a low-power power source. The efficiency of cooling fuel elements using the free convection method without additional inclusion of active cooling is considered due to design limitations of the overall dimensions of the source. Calculation estimates were made using numerical modeling of the temperature regime of the source. The object of the study is an intrinsically safe power supply with size restrictions of 200×160×65 mm with an aluminum housing. The main heat-generating elements are power transistors with a power of 1 to 6 W, mounted on the heat-dissipating parts of the housing through an insulating gasket. For stable operation of semiconductors, a temperature regime is required without exceeding the transistor temperature of 85 ° C under standard environmental conditions at an air temperature of 20 ° C and a relative humidity of 20%. The authors analyzed the heat exchange between the model of the designed power supply housing and the air environment according to the parameter of the limiting temperature of heat-generating semiconductors in a steady state. Conclusions about whether the thermal operating conditions are adequately ensured for this case are made.