Modular multilevel converters (MMCs) have become increasingly interesting in dc-dc applications, as there is a growing demand for dc-dc converters in high voltage applications. Power electronics transformers (PETs) are commonly used for high step-down ratio dc-dc power conversion, with high power rating and efficiency achieved. However, this arrangement requires a large number of high isolation...

High step-up ratio DC-DC converters with megawatt ratings are of interest in wind turbine interfaces and high-voltage direct-current systems. The modular multilevel DC-DC converter based on the standard boost converter topology but with the normal single switches replaced by a number of capacitor-clamped sub-modules. The converter is operated in resonant mode with resonance between sub-module c...

In this paper, the design of a class E2 resonant DC/DC converter, operating at UHF band, is proposed. Combining the use of GaN HEMT devices, both for the inverter and the synchronous rectifier, with high Q lumped-element multiharmonic matching networks, a peak efficiency value of 72% has been obtained at 780 MHz with a 10.3 W output power. By means of a Pulse Width Modulation (PWM) over the gat...

-In this paper, comparative evaluation of different techniques for harmonic reduction in input current of ac-dc converter is presented. Converters employing ac side switching, resonant converter, active clamped boost converter are simulated in PSIM and their performance under varying load condition with load voltage regulation is evaluated. The results revealed that active clamped boost convert...

This paper presents a high efficiency asymmetrical pulse width modulated dc-dc converter for photovoltaic application. The proposed dc-dc converter reduces the switching losses and current loss by zero voltage switching techniques. Moreover, the resonant circuit composed of the leakage inductance of the transformer and the blocking capacitor provides the zero-current switching (ZCS) turn-off fo...

The multi-phase implementation in the QR (quasi resonant) ZCS (zero current switching) SC (switched capacitor) bidirectional DC-DC converter structure has been proposed to reduce current ripple, switching loss and significantly increase the converter efficiency and power density. This approach provides a more precise output voltage to obtain voltage conversion ratios from the double-mode versus...

A novel soft switching PWM converter for high frequency ACIDC andlor DCIAC power conversion is presented by using a new parallel resonant dc-link(PRDCL) and by adopting single phase soft switching(SPSS) technique. The new PRDCL provides variable link pulse position as well as variable link pulse ,width. which is quite different feature from the other resonant dc-links and thus the PWM capabilit...

the aim of this paper is to design a fractional order sliding mode controllers (fosmc)for a class of dc-dc converters such as boost and buck converters. firstly, the control lawis designed with respect to the properties of fractional calculus, the design yields an equiv-alent control term with an addition of discontinuous (attractive) control law. secondly, themathematical proof of the stabilit...