A Multi-Objective Adaptive Control Framework in Autonomous DC Microgrid

This paper presents a multi-objective adaptive power management scheme for an autonomous de microgrid which consists of a novel adaptive gain-based proportionate charging/discharging strategy in order to provide energy balancing between battery energy storage systems (BESSs) of different capacities. As BESSs are a key component to maintain reliability and stability in an autonomous microgrid, control measures for longevity of these units should be properly investigated. Following the recommended way of charging for BESSs, i.e., constant current/constant voltage (CV) charging, the conventional methods undergo mode switching using a floating reference value to control CV charging which does not guarantee zero current when the battery is fully charged. To account for this issue, a novel progressive de-rating control scheme for PV in a seamless fashion to carry out CV charging of BESSs is done using the adaptive mechanism introduced by model reference adaptive control scheme for optimized power management between sources and loads. Furthermore, emergency events such as load shedding and load following operation of PV have also been discussed in detail. The proposed control strategy is simulated in MATLAB/SIMULINK environment and tested on a 1 kVA FPGA-based experimental prototype to validate the control approach under different scenarios.