Power Modules for inverter applications need to switch high power levels smoothly with as low an EMI as possible. Besides, they are supposed to be small and lightweight – a balancing act
in analogue and power electronics, but still a rather difficult one.
At a weight of 55 g and a volume of 49 cm3 (59 mm x 52 mm x 16mm), the »intelligent« power module (IPM) »MiniSKiiP« from Semikron with its power density of 1200V is quite small and light. It has been developed for inverter applications of up to 15 kW.
In order to achieve this power density, the power semiconductor chips and the DCB are thermally connected to the heat sink by way of an efficient pressure contact system. Since the module does not contain a base plate, the thermal resistance is rather lower than usual. The integrated SOI driver is mounted directly onto the DCB and connected to the gate terminals of the power transistors by short conductor lines via optimised gate resistors. These short connections are supposed to ensure harmonious switching behaviour and to reduce electromagnetic interference. As a result, less complex protection measures are needed to comply with the electromagnetic compatibility requirements. The short paths result in low parasitic inductances, which in turn mean lower over-voltages in the module, allowing for higher DC link voltages.
The MiniSKiiP module and the power circuit board are mounted to the heat sink using a single standard screw. The entire power, gate and auxiliary connections are made by way of pressure contacts to the PCB rather than soldered contacts. This allows for quick and cost-reduced assembly. Plus, the lack of solders further improves the quality of the entire construction and can raise the reliability.
The 1200 V 6-pack IPM has a high-voltage driver IC and Trench-Field-Stop IGBTs optimised for low switching losses and high current densities. At a rated current of 61 A, an output power of up to 15 kW is possible. 600 V Converter-Inverter-Brake versions are also available.