Analysis and Implementation of a Switching Bi-Directional BUCK-BOOST Conerter for the HEV Applications by using FLC

Abstract

A switching bi-directional buck-boost converter (SBBBC) has been proposed for integration into a vehicle-to-grid (V2G) system. This topology facilitates bi-directional energy flow between the hybrid energy storage system (HESS), comprising a Li-battery and a supercapacitor (SC), and the grid. The SBBBC offers both buck-boost capability and energy management functionality. Stability analysis of the topology in both boost and buck modes has been conducted using the state-space averaging method. Additionally, a control strategy has been devised based on the state of charge (SOC) of the energy storage system to ensure stable output voltage and current In terms of charging the Li battery, a constant current (CC) and constant voltage (CV) mode are employed. Furthermore, voltage and current controllers have been designed in the frequency domain utilizing bode plots. The overall feasibility of the topology, as well as the adequacy of the designed controller and control strategy, have been assessed to ensure effective operation within the V2G system.