Dynamic AC Power Cycling with Coupled Inverters Operating Under Application-Oriented Conditions

In order to determine the reliability of power semiconductor devices, power cycling tests are applied. Most commonly the necessary heat is generated by conduction losses in the die. As this does not reflect the loss generation in the application, this paper presents a new approach. The heat is generated by a combination of switching and conduction losses exactly as in the application. The inputs and outputs of two three-phase inverters are coupled in order to achieve circular energy flow and therefore high efficiency of the power cycling test. Furthermore, a novel 3D-printed aluminum module heat sink is designed and utilized to achieve the highest possible temperature dynamic.