Thermal Analysis of Inverters and High Frequency Transformers in the DC-DC Converters

In this paper thermal analysis of the dc-dc converter including high frequency transformer and inverter are investigated. The accurate calculations of the turn on and turn off energy losses of the power switches are necessary in thermal analysis of the inverter. As so, an improved method is presented for estimating turn on and turn off energies. Thermal behavior of the converter indicates that the inverter thermal design is not sufficient and the transformer thermal analysis should be considered. Without this attention, the transformer temperature in the core and the coil regions are raised dramatically, and the winding would be failed and also the core would be saturated at a long time in this condition. This defect leads to perish the whole transformer. Therefore, the temperature rise in the inverter and transformer are studied by the analysis of the power loss of components. The PLECS modeling and Finite Element Analysis (FEA) are carried out for the purposes. These surveys show that the transformer copper loss participates in the whole loss and temperature rise mainly. Therefore, a solution is suggested for solving the problem. FEA results also validated the proposed solutions.