Analysis of grid-connection of water wheels using photovoltaic microinverters

Abstract

To reduce the social and environmental impacts generated by energy production, the use of renewable sources has grown significantly in recent years. Small-scale pico-hydro systems have great potential and are following environmental requirements. These systems can be integrated with microgrids and are very promising for presenting production 24 hours a day. Within the scope of the SilkHouse project, a water wheel was built for the production of energy and injection into the electrical microgrid, with powers of the order of 300 W. The main objective of this thesis is to analyze the integration of pico-hydro systems with microgrids using photovoltaic microinverters. This approach allows the generators to work with variable speed. For this, two different approaches were used, the first uses a protection circuit and a DC/DC boost converter as an interface, and the other only the protection circuit. The experimental validation was implemented on a test workbench in the laboratory, and real context with the water wheel implemented at House of Silk. The data collected during the tests were from three generators, a passive load, and a microinverter. With both approaches validation, the main objective of the thesis was reached. The connection to the grid proved to be stable and the results are encouraging for the exploration of the energetic potential of pico-hydro systems.