PV Powered DC Microgrid with Plug-in Energy Support

This paper presents the establishment of a photovoltaic (PV) powered DC microgrid with plug-in energy support. The DC microgrid common DC-bus voltage is established by the PV panel through a 3-cell interleaved boost converter. The grid-connected isolated bidirectional load inverter consists of a single-phase three-wire (1P3W) 220V/110V inverter and a CLLC resonant converter. To enhance the microgrid powering quality, a hybrid energy storage system including a battery bank and a flywheel, is equipped. Moreover, a plug-in energy support mechanism is developed to let the possible harvested sources be inputted to the microgrid through the same PV interface interleaved boost converter. As the PV output energy is insufficient to support demanded power, the converter cell in the interleaved converter is switched to accept the harvested sources. The single-phase switch-mode rectifier (SMR) is formed as the basic schematic. Some measured results are presented to evaluate the established microgrid.