Closed Loop Current Mode Controlled SEPIC Re-Lift Converter System Using Time Response

  • T. Ezhilan, J. Ravikumar, B. Baskaran, S. Subramanian


The abysmal performance of a classical converter at high conduction duty due to an increase in power loss necessitates the power supply designers to use voltage-lift (VL) techniques. Ripple content present in output of power converter largely affects the performance of load. Hence soft-switched single ended primary inductor converter (SSSEPIC) is proposed between solar system and load to decrease the ripple content. This research work deals with the simulation of SEPIC re-lift converter system (SEPIC-RLCS) in closed loop mode of operation. The ripple content in output voltage is filtered with the help of a T-filter. Besides achieving a good regulated dc output, the prime objective of this work is to obtain an enhancement in dynamic response of SEPIC-RLCS. Simulation studies are performed for dual loop proportional integral (PI), proportional integral derivative (PID), fractional order proportional integral derivative (FOPID), hysteretic controller (HC) and fuzzy controlled (FC) closed loop SEPIC-RLCS by developing Matlab Simulink models. Time domain parameters are compared and comparative results demonstrate the superior performance of fuzzy controlled system. Therefore fuzzy controlled SEPIC-RLCS can be used as a good replacement for the existing dc-dc converters.