Efficiency-Driven Control of Dispatchable Sources and Storage Units in Hybrid Energy Systems

To operate as a stand-alone power system during grid power outages or peak price periods, local energy systems are equipped with storage devices and different distributed generations (DGs) such as diesel generators and renewable energy sources (RES). Power management of these hybrid systems will be challenging due to the intermittent and uncontrollable nature of many types of RES, load variations in time, availability of different energy source options with different cost function characteristics to balance the electric supply and demand, and other parameters. To operate the hybrid energy systems efficiently, a comprehensive power management method is proposed in this paper which includes two control layers. Proof of concept for the proposed power management policy was demonstrated on an experimental energy system composed of lead-acid batteries, diesel generator simulator, PV system, 3kW peak load and a utility connection.