Calorimetric Characterizations of a High Efficiency GaN Based 30 kW – 1500 V Solar String Inverter

Abstract:
This work presents the calorimetric characterizations of a high efficiency GaN-based 30 kW – 1500 VDC solar string inverter beside the electrical method. Using high voltage GaN devices, this inverter is based on a 3-level flying capacitor topology designed for high power density grid-tied applications with renewable energy sources. In the first part, the electrical characterizations show the efficiency of the inverter, for a GaN based system with input voltage of 1500 VDC and 3-ph 800 VAC on the output, these electrical measurements of the efficiency should be revised. Then, works focus on the development of a suitable calorimeter based on Peltier modules. This calorimeter is fully calibrated with the required thermal capacity measurements of the inverter. Finally, in order to demonstrate the functionality of this Peltier-based calorimeter, the inverter is characterized within several hours inside the calorimeter and results are compared to the electrical measurements.