Careful thermal management is important to ensure reliable operations even with high power losses, and high heat fluxes and ambient temperatures.
- Power modules: good thermal contact with the heat sink while ensuring electrical insulation
- Smart power module: minimising thermal resistance of the moulded packages for operations at elevated ambient temperatures
- LED: good heat dissipation as close as possible to the heat source with good thermal contact to the heat sinks
Material properties such as thermal conductivity and thermal capacity can be characterised if required. This applies in particular for Thermal Interface Materials (TIM); their properties can be measured (dependent on contact force and displacement) at Fraunhofer IZM. The thermal simulation can either be static or transient, in order to analyse the thermal capacity of the materials during rapid switching processes. The power losses in the package can be calculated by electro-thermal simulation.
In addition to calculating the heat transmission in the package, it is also important to take the cooling conditions into account. With Ansys ICEPAK/CFX, water-and air-cooling for individual packages and casings can be simulated and optimised. Using IR thermography, the static and transient behaviour of products and materials can be characterised and the thermal resistance or thermal impedance Rth / Zth directly verified.