Abstract:
DC-DC Converter plays an important role in power electronic systems for renewable energy applications. Numerous literatures have been dedicated to improving the voltage gain of DC-DC power converters that employs various voltage boosting techniques such as using voltage multiplier cell, switched capacitor (SC), switched inductor (SL) and magnetic coupling to name a few. The objective of this work is to present and analyze two new hybrid structure that is a simultaneous combination of SC and SL structures working together to provide superior gain compared to any existing voltage up and down structure alone. The proposed structure for step up voltage conversion is applied to Zeta converter to produce a hybrid high step up Zeta converter and the proposed structure for step down voltage conversion is applied to a Ćuk converter which resulted in a hybrid high step down Ćuk converter. Both of the designed converter circuits were able to provide a theoretical and simulated voltage gain ratio up to 35 times using only one active switch and without exceeding the pulse-width modulation (PWM) duty cycle ratio of 0.9 for step up conversion and without going below 0.1 for step down conversion. Working principles of the proposed converters were described in detail and their steady state analysis in continuous conduction mode (CCM) was done to derive expressions for voltage gain, current flow through individual components, voltage and current stress on the switch and diodes. Efficiency analysis was made to derive expressions for power loss in diodes, capacitors, inductors and switch which in turn provided the total power loss and conversion efficiency of the proposed converter circuits.
Description:
Supervised by
Dr. Golam Sarowar
Associate Professor,
Department of Electrical and Electronic
Engineering,
Islamic University of Technology (IUT)
Board Bazar, Gazipur- 1704
