PROJECTS Optimization of Heatsink for Efficient Power Modules Cooling
In Medium Voltage VFDs, forced convection air cooled heatsinks are often used for cooling of the semiconductors power modules. The required dimensional parameters (external dimensions, fins thickness and pitch, baseplate dimensions) of such heatsinks depend on the available flow rate, pressure drop, semiconductors module dimensions and modules layout (for multi-module heatsinks).
Using simple design calculation tools (e.g. Excel spreadsheet calculations), followed by a more detailed and accurate CFD simulations, allows design and optimization of such heatsinks. Optimized heatsink design will provide the lowest junction temperature for the semiconductors for a given available heatsink volume, flow rate and pressure drop.
Usually, more than one semiconductor module is placed on a heatsink. In such cases, the CFD simulations allow consideration of the thermal coupling between adjacent modules and optimization of the modules orientation and layout on the heatsink for maximum utilization of the heatsink surface.
During the optimization process, done by A2Z Consulting ltd., the heatsink parameters were varied and the combination that provides the lowest possible thermal resistance was found.