Increasing discrete IGBTs power density performance by improv-ing thermal design in welding machines

This paper presents an improved solution for welding machine power supplies typically using IGBT modules. The solution is based on a well-known thermal design concept for increasing heat dissipation, in which discrete IGBTs are directly mounted on the heatsink without electrical isolation. This unconventional thermal design approach increases power density and enables higher output current with lower current rate devices. Hence, it allows an extension of the application range of discrete IGBTs to power levels typically achieved by IGBT modules, reducing the cost of welding machines.