AN ANALYTICAL APPROACH TO CHARGING CHARACTERISTICS OF SUPER CAPACITORS FOR DIFFERENT EQUIVALENT CIRCUITS USING DC AND PHOTOVOLTAIC SOURCES

Abstract: Super capacitors have recently emerged as efficient energy storage devices. Unlike batteries these devices can be charged and discharged continuously without appreciable degradation in the devices. In this paper, the charging characteristics of a super capacitor have been studied and analysed using the different types of equivalent circuits of the super capacitor and the best-fit equivalent circuit has been identified by simulation results using DC source. This identified equivalent circuit is then applied for charging super capacitors by solar photovoltaic module. On comparison, the simulated results of the charging characteristics using photovoltaic module is seen to tally closely with the experimental ones. The paper also describes the charging characteristics of the conventional capacitor and super capacitor using mathematical expressions of the solar photovoltaic cell and again compares the characteristics using the experimental results. These charging characteristics as derived mathematically are also found to closely follow the same.

Keywords: Supercapacitor, Transmission branch model, RC branch model, Energy storage system, Solar photovoltaic equation