Hybrid Renewable Microgrid System Based DC-bus Scheme for Residential Load Applications

Integration of renewable energy sources (RESs) with energy storage systems (ESSs) has become a vital solution to overcome energy shortage in rural areas. In this paper, a small-scale hybrid renewable microgrid (MG) based DC-bus scheme is presented. This kind of configuration eliminates issues related to frequency stability, synchronization and reactive power flow. Both the solar power generating system (SPGS) and the wind power generating system (WPGS) are manipulated to extract their maximum available powers. A battery storage system (BSS) is used to supply the loads during critical periods to certify supplying loads round-the-clock. Operation of the battery is moderated using a battery control unit (BCU) based PI controller which supervises the different modes of operation. Moreover, the BCU ensures a fixed DC-bus voltage at different circumstances such as variable wind speed, variable radiation and loading events. Furthermore, the continuous load feeding at constant voltage amplitude and frequency for balanced loading conditions is accomplished using the prime inverter controller.