NON RESONANT INDUCTIVE LINK DC-DC CONVERTERS FOR INDUSTRIAL APPLICATIONS

Abstract

High switching-frequency DC-DC converters with galvanic isolation are industry workhorse for wide range of applications. Power converter topologies are generally classified into resonant and non-resonant. The non-resonant converters are controlled by simple fixed switching frequency PWM control and their performance is immune to manufacturing variations. Non-resonant converters suffer from drastic efficiency reduction at mid and light loads due to loss of inherent soft-switching of semiconductor devices and fail to meet Energy Star efficiency standards. Resonant converters utilize an intermediate resonant tank and are controlled by variable frequency control. Resonant converters enjoy a wide range of natural soft switching but suffer from dynamic oscillations due to presence of resonant tank for which complicated trajectory control methods are necessary and exhibit a poor stability. This thesis proposes a novel inductive link non-resonant DC-DC converter with extended natural soft switching range for meeting energy star efficiency standards, controllable by simple frequency control and possess global asymptotic stability. Its forms in both isolated half-bridge and full-bridge configurations are investigated in this thesis and developed for application in LED lighting, data-center power supply and grid-integration of Solar-Photovoltaics.