DC Power Metering in Low-Voltage Microgrids: Definitional and Methodological Issues

Renewable energy sources are typically operated in DC. Their interconnection to the AC grid relies on dedicated inverters that pose several challenges in terms of lower inertia and poorer power quality. In order to avoid these challenges, low-voltage DC grids may represent a promising solution for small grid portions with controlled power flows. To fill the standardization gaps, the paper discusses the suitable definition of DC power in distorted conditions and evaluates the possible measurement errors due to real-world disturbances.