Galvanically Isolated Power Supply for Gate Drivers in High Voltage Applications

Abstract:
This work presents a feasibility study of power supply solutions for isolated gate drivers meant for use in high voltage applications. At high potential differences, maintaining the standard specified creepage and clearances increases the size and volume of the integrated system. Therefore, this becomes a bottleneck in space-constrained applications. In this work, the galvanically isolated power supply for gate drivers designed to drive a modular multilevel converter is realized by using a common primary voltage source to supply multiple gate driver units over individual isolation transformers. Two configurations of isolation have been investigated, and two further power supply arrangements have been constructed and tested in nominal operation. All arrangements have their own advantages and disadvantages, and therefore, a preferred selection is dependent on application, and the available volume to integrate the solution. A comparison of the configurations in terms of their performances, robustness against partial discharges and the associated construction effort concludes this paper.