The DC to DC applications are used in many industrial, medical and electronic converters, because of their high efficiency, small size and light weight. In spite of these features, they suffer from several disadvantages such as unregulated output voltage and lack of stability due to the change in input voltage and sudden change in load or system parameters.
This paper presents the mathematical model of the SEPIC converter circuit operating in the continuous conduction mode (CCM) in state-space form and the converter circuit output is investigated. Fuzzy Logic controller with manual tuning is designed for controlling the converter circuit. Fuzzy Logic based Bacteria Foraging Algorithm (FLC&BFA) Controller is proposed to design controller for controlling the switch operation of the SEPIC converter circuit for regulation of its output voltage and getting good performance.
Simulation results were analyzed and compared the response performance of system for different resistive loads and reference voltages, it was noticed that there was a significant performance improvement for the controller states used the bacteria foraging algorithm, compared with the state of fuzzy logic controller with manual tuning and also compared with the open loop system. also the unregulated output voltage issue was overcome in the present of external disturbance and it need a negligible time for tuning.