Resonant DC-DC Converter for Photovoltaic Systems
Abstract
This paper describes a step-up DC-DCconverter, which main task is to increase the voltage from a
low level drawn from a photovoltaic (PV) panel, to a high
controlled level for a connected inverter. The converter also
provides an electrical isolation of PV panels from the grid.
In the DC-DC converter a resonant LLC topology is used.
The converter operates at high switching frequency to
achieve small size of the power transformer. The main
benefit of this converter is zero-voltage switching (ZVS) of
primary MOSFETs and zero-current switching (ZCS) of
rectifier diodes over the entire operating range. Advantage
of used topology is that the converter can be controlled by a
simple 8bit microcontroller (MCU). A laboratory model
with maximum 95.5 % efficiency was built to
References
Ya Liu, “High Efficiency Optimization of LLC Resonant
Converter for Wide Load Range”, Blacksburg, Virginia 2007
Bo Yang, “Topology Investigation Front End DC/DC Power Conversion for Distributed System”, Virginia 2003
ST Microelectronics, “LLC resonant half-bridge converter design guideline”, October 2007
Mingping Mao, Dimitar Tchobanov, Dong Li, Martin Maerz, Tobias Gerber, Gerald Deboy, Leo Lorenz, “Analysis and Design of a 1 MHz LLC Resonant Converter with Coreless Transformer Driver”, 2007
Hang-Seok Choi/Ph.D, FPS Application group, “Half-bridge LLC Resonant Converter Design Using FSFR-series Fairchild Power Switch”, 2007
Christophere Basso, “Understanding the LLC Structure in Resonant Applications”, 2008
STMicroelectronics, “Simplified Analysis and Design of Seriesresonant LLC Half-Bridge Converters”, 2006
Fu Keung Wong, B. Eng. and M Phil., “High Frequency
Transformer for Switching Mode Power Supplies”, Griffith
University, Brisbane, Australia, March 2004
Kácsor, G. , Špánik, P., Lokšeninec, I.: Simulation Analysis of a Zero Voltage and Zero Current Switching, DC/DC Converter. In proceedings: Transcom ´03, Žilina, Slovak Republic, 23 – 25 June 2003, pp. 47-50
Hamar, J., Buti, B., Nagy,I.: Dual Channel Resonant DC-DC Converter Family. EPE Journal, Volume 17, Issue 3, Jul-Sep. 2007, pp.5-15.
