Decentralized generator scheduling in a nanogrid using DC bus signaling

A nanogrid is a small isolated DC power system that uses distributed renewable energy sources in conjunction with storage to supply continuous power to small local loads. Power electronic converters interface the sources and loads to the nanogrid. Power balance in a nanogrid is achieved by scheduling the sources in a decentralized fashion to maintain the modularity and reliability inherent in its distributed structure. This paper presents DC bus signaling as a means of generator scheduling and power sharing in a nanogrid under steady-state conditions. DC bus signaling is a novel control strategy that is a hybrid of the voltage level signaling and voltage droop schemes. Discrete voltage levels on the nanogrid bus indicate the state of the system and determine the behaviour of each source. A case study and simulation results demonstrate the application of DC bus signaling.