A 20 kW, 3-level flying capacitor 1500 V inverter with characterized GaN devices for grid-tie applications

This work presents the static and dynamic characterizations of high voltage GaN power devices (GaN FET 900 V and GaN HEMT 1200 V) in order to implement a 3-level flying capacitor 1500 VDC inverter for high power density grid-tie applications with renewable energy sources such as solar and hydrogen energy. In the first part, the static characterizations are shown for two selected GaN power devices. Then these GaN devices were placed in a double-pulse-test-bench dedicated to the dynamic characterizations intended to observe the switching behaviors of the devices under the nominal voltage and current. Finally, in order to demonstrate the compactness of the converter, these GaN devices were implemented in a 20 kW, 3-level flying capacitor 1500 VDC inverter with the full-custom suitable passive elements of the output filters connected to the 800 VAC 3-phase grid.