An improved dynamic performance of bidirectional SEPIC-Zeta converter based battery energy storage system using adaptive sliding mode control technique

An improved dynamic performance of DC-DC bidirectional SEPIC-Zeta converter based battery energy storage system (BESS) has been achieved using adaptive sliding mode control (SMC) technique. The micro-grid concept is gaining importance for integrating various nonconventional energy sources throughout the world. Nowadays, both DC and AC micro-grid systems are employing BESS for getting various advantages such as minimization of power fluctuations, excess or emergency power support etc. In this application, controlled charging and discharging operation of the concerned battery bank is extremely needed. In this scenario, DC to DC bidirectional converter such as combined SEPIC-Zeta converter is considered to facilitate dynamic charging and discharging operation of the concerned battery. Conventional proportional-integral-derivative (PID) controller based control strategy for the bidirectional converter can not always meet the dynamic performance requirements under charging and discharging operation cycles of the battery. Therefore, adaptive SMC action has been proposed to improve both transient and steady state behavior of the BESS. In addition to this, the proposed model can be operated satisfactorily under changed operating condition. The proposed concept is validated via various simulation studies using MATLAB-SIMULINK software. The experimental study is also performed on a prototype of the BESS to validate adaptive SMC case.