A study on the DC distribution system for small scale residential buildings

Nowadays, most of electrical load that we use is suitable for DC instead of AC. The portion of DC loads to AC loads is increasing dramatically. Also, environmentally friendly renewable energy sources such as photovoltaics and fuel cells produce DC. It means that energy conversion could be effective with DC distribution compared to AC because much potion of loads and power source are changed to DC from AC. Therefore, DC distribution for home and a building has been attractive issue in research area. This paper deals with the core technologies of DC electrical distribution at small-scale residential building that is composed of converted DC home appliances, a grid-interactive converter for regulating bus voltage, bidirectional converter for battery power interface, and renewable energy simulator. To prove and test DC system, the proposed devices and converters are built up with DC loads. Many important configurations and considerations are explained with test facilities.