EPE Association: EPE 1993 - 16 - Lecture Session L6a: POWER SUPPLIES: ZERO AND SOFT SWITCHING, MAGNETICS

EPE 1993 - 16 - Lecture Session L6a: POWER SUPPLIES: ZERO AND SOFT SWITCHING, MAGNETICS
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1993 - Conference > EPE 1993 - 16 - Lecture Session L6a: POWER SUPPLIES: ZERO AND SOFT SWITCHING, MAGNETICS

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   ANALYSIS OF A CONSTANT FREQUENCY SERIES PARALLEL MULTIRESONANT CONVERTER FOR HIGH POWER AND INCREASED OUTPUT VOLTAGES
By U. Kirchenberger; K. Fischer; D. Schröder [View]
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Abstract: For increased output voltages only resonant switching and capacitive output filters reduce the reverse recovery effect of the rectifier diodes significantly. In high power applications less switching losses of the active switches like IGBTs result in desired higher switching frequencies. The proposed constant frequency series-parallel multiresonant converter CSPRC combines the advantages of resonant switching, capacitive output filter and constant switching frequency. The converter characteristics are obtained with the unified state space analysis. The influence of the ZVS snubber capacitances on the converter operation region is important and therefore considered in the analysis. The analysis presented can also be used for the frequency variable series and series-parallel converters in over- and underresonant regime. The mixed Zero current (ZCS) and Zero Voltage Switching (ZVS) operation of the converter is shown to be the most favourable operation for minimum component stress. Experimental verification of the analysis is given.

   A NEW APPLICATION FOR ZERO-CURRENT-SWITCHED FULL-WAVE RESONANT CONVERTERS
By M. A. E. Andersen [View]
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Abstract: An entirely new application for high-frequency resonant converters is presented. It is for use in digital audio power amplifiers and could be called a 1-bit power D/A converter. lt involves the amplification of the 1-bit moderately oversampled and highly noise shaped digital input signal to a level equal to that of an audio power amplifier. The amplification makes use of high frequency zero-current-switched full-wave buck and boost resonant converters followed by an analogue low pass filter before the loudspeaker.

   SOFT-SWITCHING PWM TECHNIQUES AND THEIR APPLICATIONS
By Guichao Hua; Fred C. Lee [View]
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Abstract: Recently, a number of soft-switching pulse-width-modulated (PWM) converter techniques have been proposed, aimed at combining the desirable features of both the conventional PWM and resonant converters while avoiding their respective limitations. In this paper, four classes of soft-switching PWM converters are reviewed, including the zero-voltage-switched (ZVS) quasi-square-wave converters (QSCs), ZVS-PWM converters, zero-current-switched (ZCS) PWM converters, and zero-voltage-transition (ZVT) PWM converters: their merits and limitations are assessed. Experimental results of several prototype of converters are presented to illustrate each class of converters.

   LOW PROFILE HIGH FREQUENCY POWER SUPPLIES USING THICK FILM PLANAR TRANSFORMERS
By P. G. Barnwell; T. J. Jackson [View]
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Abstract: A programme of work investigating transformers for use in high switching speed power supply units is described. The transformers are of a planar structure, allowing a low profile. The use of thick film on ceramic technology allows efficient heat transfer from the transformer, combined with low resistivity conductor tracks. An advanced form of planar transformer, intended for operation at 2 MHz, has been researched, and is shown to allow a particularly compact structure. Finite element modelling techniques with a three dimensional (3D) model are used to predict transformer performance and hence allow optimisation of the design. Resulting from this work a test transformer has been designed and fabricated. This transformer achieves efficiencies of 93%, in excellent agreement with the theoretical predictions.

EPE 1993 - 16 - Lecture Session L6a: POWER SUPPLIES: ZERO AND SOFT SWITCHING, MAGNETICS
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1993 - Conference > EPE 1993 - 16 - Lecture Session L6a: POWER SUPPLIES: ZERO AND SOFT SWITCHING, MAGNETICS
	[return to parent folder]

	ANALYSIS OF A CONSTANT FREQUENCY SERIES PARALLEL MULTIRESONANT CONVERTER FOR HIGH POWER AND INCREASED OUTPUT VOLTAGES By U. Kirchenberger; K. Fischer; D. Schröder	[View] [Download]
Abstract: For increased output voltages only resonant switching and capacitive output filters reduce the reverse recovery effect of the rectifier diodes significantly. In high power applications less switching losses of the active switches like IGBTs result in desired higher switching frequencies. The proposed constant frequency series-parallel multiresonant converter CSPRC combines the advantages of resonant switching, capacitive output filter and constant switching frequency. The converter characteristics are obtained with the unified state space analysis. The influence of the ZVS snubber capacitances on the converter operation region is important and therefore considered in the analysis. The analysis presented can also be used for the frequency variable series and series-parallel converters in over- and underresonant regime. The mixed Zero current (ZCS) and Zero Voltage Switching (ZVS) operation of the converter is shown to be the most favourable operation for minimum component stress. Experimental verification of the analysis is given.

	A NEW APPLICATION FOR ZERO-CURRENT-SWITCHED FULL-WAVE RESONANT CONVERTERS By M. A. E. Andersen	[View] [Download]
Abstract: An entirely new application for high-frequency resonant converters is presented. It is for use in digital audio power amplifiers and could be called a 1-bit power D/A converter. lt involves the amplification of the 1-bit moderately oversampled and highly noise shaped digital input signal to a level equal to that of an audio power amplifier. The amplification makes use of high frequency zero-current-switched full-wave buck and boost resonant converters followed by an analogue low pass filter before the loudspeaker.

	SOFT-SWITCHING PWM TECHNIQUES AND THEIR APPLICATIONS By Guichao Hua; Fred C. Lee	[View] [Download]
Abstract: Recently, a number of soft-switching pulse-width-modulated (PWM) converter techniques have been proposed, aimed at combining the desirable features of both the conventional PWM and resonant converters while avoiding their respective limitations. In this paper, four classes of soft-switching PWM converters are reviewed, including the zero-voltage-switched (ZVS) quasi-square-wave converters (QSCs), ZVS-PWM converters, zero-current-switched (ZCS) PWM converters, and zero-voltage-transition (ZVT) PWM converters: their merits and limitations are assessed. Experimental results of several prototype of converters are presented to illustrate each class of converters.

	LOW PROFILE HIGH FREQUENCY POWER SUPPLIES USING THICK FILM PLANAR TRANSFORMERS By P. G. Barnwell; T. J. Jackson	[View] [Download]
Abstract: A programme of work investigating transformers for use in high switching speed power supply units is described. The transformers are of a planar structure, allowing a low profile. The use of thick film on ceramic technology allows efficient heat transfer from the transformer, combined with low resistivity conductor tracks. An advanced form of planar transformer, intended for operation at 2 MHz, has been researched, and is shown to allow a particularly compact structure. Finite element modelling techniques with a three dimensional (3D) model are used to predict transformer performance and hence allow optimisation of the design. Resulting from this work a test transformer has been designed and fabricated. This transformer achieves efficiencies of 93%, in excellent agreement with the theoretical predictions.