Thermal CAD of power hybrid devices using light computer means [microcomputer application]

The authors present the practical implementation on microcomputer of a new method of temperature calculation with a view to thermal CAD of power hybrid circuits. This method is based on the notion of a punctual heat source, and of image sources used to represent simple boundary conditions such as adiabatic or isothermal planes. It is implemented on an IBM PC-XT computer and the program written in Pascal. Some practical examples are presented and comparison with experiment performed. The maximum number of temperature points at the surface in an actual version of the program is 100×76. The graphical representation of numerically obtained results is compatible with the infrared thermograph HUGHES TVS-4100. The problems of the speed of computation have been treated with special care. For temperature calculation in hybrid power circuits, this method is a serious contender to the classical finite element method regarding its rapidity, precision and cheapness