Analysis of Battery Lifetime Extension in a Small-Scale Wind-Energy System Using Supercapacitors

TLDR

Renewable power systems experience irregular partial charge/discharge cycles that degrade battery life and raise costs. The study proposes a battery/supercapacitor hybrid system to extend battery life in small remote wind‑power installations. The authors design a supervisory control algorithm and hardware, simulate a dynamic model of wind‑speed and load variations, and build a prototype to validate the hybrid system’s feasibility. Experimental results show that diverting short‑term cycles to a supercapacitor can significantly extend battery life.

Abstract

Due to the variable characteristics of renewable generation, batteries used in renewable-power systems can undergo many irregular, partial charge/discharge cycles. In turn, this can also have a detrimental effect on battery lifetime and can increase project costs. This study presents a method of improving battery lifetime in a small-scale remote-area wind-power system by the use of a battery/supercapacitor hybrid energy storage system. The supervisory control algorithm and hardware implementation are described and projected long-term benefits of the proposed system are assessed by simulation. A representative dynamic model of the overall system, incorporating realistic wind-speed and load-power variations has been developed. An analysis is presented of the potential improvement in battery lifetime that is achievable by diverting short-term charge/discharge cycles to a supercapacitor energy-storage system. This study introduces a method by which supercapacitor energy storage systems and control algorithms can be evaluated and implemented in the application area considered. The composition of a prototype test system is described and experimental results are presented to demonstrate system feasibility.