Modular Multilevel Converter (MMC) attracts greatly increasing interests in medical pulse generators. This digest introduces a novel design of parallel-connectivity-enabled submodules based on GaN HEMT. The GaN HEMT features in the module design because of their excellent switching speed. Different from conventional power electronic use, this digest adapts the submodule design with extra consideration to its pulse generating application. The thermal design emphasizes more on the dynamic performance. FAE simulation is performed to verify the thermal improvement. Meanwhile, the heads and tails of the pulses are optimized to relieve the stress on modules. The individual submodule can deal with 50 V / 50 A power with switching speed up to MHz.
