A new control approach for PV system with hybrid energy storage system

In this paper, a new control approach is proposed for PV system with hybrid energy storage system (HESS) in isolated DC grid application. The proposed control approach solves the current controller conflict problem in HESS and provides faster DC link voltage restoration. In the proposed control approach a predictive term is used to control the battery current and the supercapacitor (SC) current. In the proposed control approach the voltage error term and the uncompensated power from the battery is added to the supercapacitor current reference to achieve faster DC link voltage restoration and less stress in the battery system. The system parameters design and closed loop system stability analysis of the proposed control approach are discussed in detail in the paper. The effectiveness of the proposed control approach is verified by simulation studies.