Distributed control strategy for a grid-connected hybrid system with batteries and renewable sources

The paper deals with a distributed control strategy for a grid-connected hybrid system composed of renewable energy sources and batteries. The energy balance in the hybrid system is obtained by regulating the dc-bus voltage. In this study, all the elements can ensure the stability of the DC-bus voltage and the grid interventions are reduced. The control strategy is a rule-based strategy where a set of rules are defined and implemented using state machines. The novelty in this strategy is that there is no specific communication network between the elements of the system, the value of the DC-bus voltage is the only information that allows the several elements to interact. This condition permits to easily plug or unplug an element in the system without changes in the control scheme. The system configuration, the control method, the simulation results, analysis and future perspectives are all presented.