Design and Control of Three-phase Smart Inverter Using Gate-drive Integrated Gallium Nitride (GaN) Devices for Solar Energy Integration

With
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major increase in the integration of renew-able energy sources, along with the use of solar inverters, the need for smart inverter technology is higher than ever. It is desirable for these smart inverters to have high power density, operate with maximum efficiency, and provide grid services such as voltage and frequency regulation. The power delivery of these grid-supporting inverters can be regulated through output current control, which is varied based on sensed grid conditions. This paper details the analysis, design, and hardware testing of a 3-ϕ smart inverter that monitors grid conditions and dynamically alters the active and reactive power fed to the grid as needed, thus providing grid services through voltage and frequency regulation. Controller design calculations are presented, and simulation results of transient conditions are provided. Experiments on a 1 kVA hardware prototype using a grid emulator show proof-of-concept for a highly efficient 3-ϕ smart solar microgrid inverter.