Coordination of Energy Storage Systems and Closed Loop Converter for Regulating Voltage of PV System

Intermittency is the major concern associated with Renewable Energy Sources (RES). These sources alone cannot guarantee the regulated load voltage and power requirements, hence they are used in conjunction with storage systems. However, storage system design proves more effective when multiple storage systems like battery and super capacitors with different capacities are included. Battery serves as main back up where as supercapacitor serves as secondary back up to improve voltage profile. Super capacitor relieves the over stress on the converter and avoids unnecessary switching on of battery in response to transient voltage fluctuations. The main objective of this paper is to propose a control scheme which can switch either super capacitor or battery, depending upon the severity of voltage fluctuation to obtain regulated voltage. This helps system to operate at maximum efficiency, reduced converter losses and importantly increased storage lifetime.