Power management control for solar photovoltaic based DC system

DC system for solar photovoltaic (PV) application is gaining popularity due to high efficiency and reliability. This system could be interconnected to ac and dc grids. For high availability of power supply to loads, energy storage elements are interconnected using dc-dc converters. Power management control for this system is necessary to ensure high utilization of renewable sources and stable operation of system. DC bus signaling technique, suggested in literature, does not consider extreme system operation, for instance battery fully charged or battery deep discharge conditions. A modified technique based on dc bus voltage signaling considers the above mentioned conditions only for one battery storage unit. Moreover, power sharing among multiple battery units is not discussed. To address these limitations, this paper presents a distributed power management scheme based on dc bus signaling controller. The proposed scheme is capable of controlling multiple storage, solar PV and grid converters. Detailed simulation studies are carried out to verify the effectiveness of the scheme and results are included.