![[Funakingdom]](image/pukiwiki.png "[Funakingdom]")
#author("2023-02-18T10:45:54+09:00","default:funaki","funaki") #author("2023-02-20T12:32:09+09:00","default:funaki","funaki") Power modules combine multiple power devices in a single package to perform switching operations in a power conversion circuit. In order to arrange multiple power devices with different operating reference potentials in a single package, wiring patterns of copper, aluminum, or other materials are formed on a ceramic insulating substrate or insulating sheet. Since multiple power devices in a module generate heat respectively, thermal interference is caused by the loss of neighboring power devices, resulting in a larger temperature rise compared to the loss of a single power device. Increasing the spacing between power devices can reduce the thermal interference problem, but on the other hand, the parasitic inductance of the wiring becomes larger due to the longer wiring length. The larger the parasitic inductance, the larger the surge voltage generated by the current change rate di/dt in the switching operation of the power device. The surge voltage can be reduced by shortening the wiring length or by reducing the di/dt to lower the switching speed, but the former causes greater thermal interference and the latter increases switching losses. Thus, there is a tradeoff between thermal interference and surge voltage of power devices in power modules. In optimal structural design of power modules, multi-objective optimization for thermal and electrical performance is performed to achieve higher performance of power modules. #ref(./OptimalDesign.png,50%); #ref(./OptimalDesign_eng.png,50%); [[Research work]]
