PCB Embedded Semiconductors for Low-Voltage Power Electronic Applications

Abstract

Power conversion applications in the low voltage (LV) range (≤ 1.2 kV)—such as three-phase inverters—are required to operate at higher efficiencies, higher ambient temperatures, increasingly smaller form factor, and higher power density. Up to now, most research has focused on voltages up to 650 V for printed circuit board (PCB) embedded power electronics. This research evaluates a novel three-phase invertor module based on six insulated gate bipolar transistors and six diodes rated to 1.2 kV and 25 A each. This unique module is compared to the Semikron MiniSKiiP 23AC126V1. This paper considers some key details of the PCB embedding assembly process, a comparative switching performance assessment, measurement of thermal resistance, comparative lifetime, and electric insulation. First, a detailed outline of the package is presented including the top- and bottom-side metallization and the copper interconnect technology. The switching performances of both modules are compared for turn-ON and turn-OFF currents for a waveform at 600 V and 25 A at 150 °C. A finite-element-method thermal simulation demonstrates up to 44% lower thermal resistance for the PCB embedded package than that of the traditional wire-bonded direct bonded copper (DBC) package for an identical applied current and cooling condition. Furthermore, both packages are active power cycled to failure with the PCB embedded package demonstrating superior lifetime to the traditional DBC module. Finally, the maximum breakdown limit and the onset of partial discharge with the embedded PCB module are reported for both aged and non-aged conditions. The overall findings identify the promising application of PCB embedded power electronics for LV power conversion.