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An Isolated Soft-switching Buck-Boost Converter
Utilizing Two Transformers and Embedded
Bidirectional Switches on Secondary-side For Wide
Voltage Applications
Abstract:
A dual-phase-shift controlled isolated buck-boost converter is presented for wide
input or output voltage range applications. Two transformers and a voltage-doubler
rectifier with embedded bidirectional switch are employed. The primary windings
of the two transformers are in series and the secondary windings are in parallel.
With optimized dual-phase-shift modulation strategies, zero voltage switching
(ZVS) is achieved for both the primary- and secondary-side power MOSFETs in a
wide load range. The reverse recovery problem of rectifying diodes is eliminated
as well. Leakage inductances of the transformers are utilized for power
transferring. The voltage stresses of primary-side and secondary-side power
MOSFETs are clamped to the input voltage and half of the output voltage,
respectively. Besides, the converter can operate in the buck, balance and boost
modes to achieve a wide voltage range. The operational principles are analyzed
and experimental results of a 1-kW 100-kHz prototype are provided to verify the
effectiveness of the presented converter.
Existing system:
Isolated DC-DC converters with wide input/output voltage ranges have been
widely used in the applications of renewable energy, storage and electric vehicles
power systems.
Proposed system:
A dual-phase-shift controlled soft-switching DC/DC converter for high-efficiency,
wide voltage range and galvanic isolation application is proposed. With optimized
control scheme, soft switching is achieved for all MOSFETs and diodes within a
wide load range. Leakage inductance of transformers is used to for power
transferring and the voltage spike problem is overcome.
Circuit diagram:
Application:
Isolated DC-DC converters with wide input/output voltage
ranges have been widely used in the applications of renewable
energy, storage and electric vehicles’ power systems.
Reference:
[1] D. S. Gautam, F. Musavi, W. Eberle, and W. G. Dunford, “A zero voltage
switching full-bridge DC-DC converter with capacitive output
filter for plug-in hybrid electric vehicle battery charging,” IEEE Trans.
Power Electronics, vol. 28, no. 12, pp. 5728-5735, Dec. 2013.
[2] H. Wu, Y. Xing, “Families of forward converters suitable for wide input
voltage range applications,” IEEE Trans. Power Electronics, vol. 29, no.
11, pp. 6006-6017, Nov. 2014.
[3] Y. Zhao, W. Li, Y. Deng, and X. He, “Analysis, design, and
experimentation of an isolated ZVT boost converter with coupled
inductors,” IEEE Trans. Power Electronics, vol. 26, no. 2, pp. 541-550,
Feb. 2011.
[4] Y. Wang, W. Liu, H. Ma, L. Chen, “Resonance analysis and soft switching
design of isolated boost converter with coupled inductors for
vehicle inverter application,” IEEE Trans. Power Electronics, vol. 30, no.
3, pp. 1383-1392, Mar. 2015.