Future Home DC-based Renewable Energy nanoGrid System
In the “High Energy Efficient House”, solar arrays, wind and batteries are used to feed the main DC bus, as well as grid and plug-in hybrid electric vehicles forming the so-called nanoGrid system. nanoGrid can island, work in the stand-alone mode and reconnect to the utility grid performing smooth transitions between the different modes of operation.
The concept accepted for the voltage regulation in the nanoGrid system is the adaptive droop control based on the DC-bus signaling technique as shown in the Fig. 2. Having this, communication between the system converters in a sense of control is avoided and converters work in the mode of operation determined by the voltage levels on their terminals.
The nanoGrid has Supervisory Control and Data Acquisition system (nanoSCADA), hybrid DSP and FPGA platform that communicate with all the converters, as well as with all the appliances in the system, through the wireless network channel in order to fully utilize power management algorithms. The nanoSCADA is able to connect to the internet and check the weather forecast for the future period in order to fully utilize energy storage.