International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

A methodology for thermal analysis of the operation of transistors in a welding inverter is proposed. The results for heating of the transistors obtained by numerical modelling using the finite element method (FEM) are presented. A thermal problem has been solved taking into account the forced movement of air. Based on the obtained solutions, the maximum temperatures on the surface of the heat sink and in the crystal of the field-effect transistor are presented, depending on the speed of air movement and the temperature of the environment in continuous mode of operation of the power source. The presented analysis is applicable to select appropriate heat sink and fan. Results are useable during design of the power source oriented to wire arc additive manufacturing.

The miniature and low-power devices with long service life in hard operating conditions like the 14C ß-decay energyconverters indeed with eternal resource for integrated MEMS and NEMS are considered. Authors will discuss how to create a power source for MEMS devices, based on SiC/Si porous structure, which are tested to be used as the β-decay energyconverter of radioactive carbon-14 into electrical energy. This is based on the silicon carbide obtaining by self-organizing mono 3C-SiC endotaxi on the Si substrate.