DESIGN AND PERFORMANCE EVALUATION OF A BATTERY/SUPERCAPACITOR HYBRID STORAGE SYSTEM FOR RENEWABLE ENERGY APPLICATIONS

ABSTRACT

The development of any nation and its economy at large is centred on reliable and efficient power supply. Many developing nations are yet to actualise this feat, and therefore, there is need to strategize to meet the ever-rising demand for energy. Battery-based inverter systems have over the years provided additional power supply to critical loads, in the absence of public power supply. However, high peak charging/discharging power demands results in the degradation of the battery. A hybrid combination of batteries and other technologies such as super-capacitors can help to provide a single power system with both high energy and power densities. The aim of this project is the design and performance evaluation of a battery/supercapacitor hybrid storage system for renewable energy applications as this can provide an energy source with high power density and high energy density. The paralleling of the battery and the super-capacitor to obtain a single source was established using an Automatic Switching System. Results showed that considerable amount of initial transient current was supplied by the super-capacitor. The peak current drawn from the battery is reduced, which increases the lifetime and performance of the battery. This results in high-cost saving as well as improved reliability, which has become increasingly necessary in the alternative power technology.