EPE Association: EPE 1997 – 78: Dialogue Session DS2a: MULTILEVEL AND MATRIX CONVERTERS

EPE 1997 – 78: Dialogue Session DS2a: MULTILEVEL AND MATRIX CONVERTERS
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1997 - Conference > EPE 1997 – 78: Dialogue Session DS2a: MULTILEVEL AND MATRIX CONVERTERS

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   THREE-PHASE THREE-LEVEL VOLTAGE-SOURCE CONVERTERS COUPLED WITH HARMONIC CANCELING INTERPHASE REACTORS
By K. Oguchi; N. Nakajima; T. Sano [View]
[Download]

Abstract: For high power applications, double three-level voltage-source converters coupled with harmonic canceling interphase reactors are proposed. A voltage wave notching method is applied to control fundamental voltages and eliminate two or four lower harmonic components. The increased harmonic components due to the notching can be canceled by the harmonic canceling reactors. Thus, the proposed system can produce relatively less distorted m put current waveforms at lower switching frequencies.

   STABILITY ANALYSIS OF MULTILEVEL CONVERTERS WITH IMBRICATED CELLS
By J.L. Duarte; P.J.M. Julicher; L.J.J. Offringa; W.D.H. van Groningen [View]
[Download]

Abstract: By taking the influence of parasitic components explicitly into account, a small signal sampled-data description of a multilevel converter with imbricated cells is derived. Instead of stressing numerical solutions, the derivations are worked out following an analytical formulation. Although attention is paid to a three-level chopper, the modelling approach is appropriate to other multilevel converters as well. Simulation results and experimental measurements confirm the validity of the proposed model.

   FIVE LEVEL LABORATORY VAR COMPENSATOR WITH SEPARATED FLOATING DC VOLTAGES
By T. W. Rasmussen [View]
[Download]

Abstract: The paper discusses an IGBT model of a 10 kvar five level nonclamped compensator built to investigate multilevel system principles. Pulse wide modulation with selective harmonic elimination for multilevel converters is described where one of the solutions is made in the laboratory model. Also the d.c. voltage sharing between the capacitors from the model is shown and methods for this regulation is given.

   CONTROL STRATEGY FOR MULTILEVEL CONVERTER APPLIED FOR ELECTRIC POWER SYSTEM
By Noriyuki Kimura; Akira Matsumoto; Toshimitsu Morizane; Katsunori Taniguchi [View]
[Download]

Abstract: Multilevel converter using GTO thyristor can reduce higher harmonics without increasing switching frequency and loss. However, keeping dc capacitance voltage is difficult for fundamental frequency switching single converter. This paper discusses the cause of unbalance of dc capacitor voltage and propose double converter configuration for the solution.

   SERIAL CONNECTION : SOFT SWITCHING, A WAY TO REDUCE PARASITIC OVERCURRENTS
By N. LAPASSAT; D. CHATROUX; D. LAFORE [View]
[Download]

Abstract: This paper describes how soft switching can be used in serial connection of power components in order to reduce overcurrents due to parasitic capacitances to ground during turn on. In hard switching, this phenomenon become crucial when the number of serial connected switches increases. Indeed, the parasitic current in the lowest potential devices increases losses and can even exceed their pulse current rating. Particular attention is given to the way resonant inductors can be placed in series with devices in order to reduce these overcurrents. This makes the achievement of an over 50kV switch easier for the use in high voltage static converter.

   SWITCH-EFFECTIVE MODULATION STRATEGY FOR MATRIX CONVERTERS
By Ake Christensson [View]
[Download]

Abstract: This paper describes a modulation strategy for the matrix converter. The proposed method minimises the number of required switchings for each power pulse, while achieving sinusoidal output voltage and sinusoidal input current. The method uses the complex vector approach. A mathematical description of the matrix converter is given. Simulation results as well as measurements from an IGBT-based, 30 kVA experimental prototype are presented.

   A MATRIX CONVERTER SWITCHING CONTROLLER FOR LOW LOSSES OPERATION WITHOUT SNUBBER CIRCUITS
By R. Cittadini; J-J. Huselstein; C. Glaize [View]
[Download]

Abstract: A Matrix Converter can reproduce many functions in power electronics. However, this converter is only composed of wholly controlled switches. The resulting specific forced commutation must be cleverly managed. In this paper, we show how to obtain optimal forced commutation in a Matrix Converter without additional stress on power semiconductors and without snubbers. Experimental results of a 3 kVA direct AC/AC single phase converter are reported.

   A 3kW UNIT-POWER-FACTOR MULTILEVEL RECTIFIER BASED ON A DOUBLE-BOOST CONVERTER
By P. Bartholoméüs; P. Le Moigne [View]
[Download]

Abstract: This paper presents the study and the tests of a double-boost rectifier working in multilevel operation. The particular working of this new converter is described. Its control process is defined in order to obtain a sinusoidal input current and to balance the DC output voltages. Finally, test comparisons of a 3 kW conventional boost rectifier with a 3-level one present several advantages of the latter and show that this converter is well adapted to high power factor applications.

   SINGLE- AND THREE-PHASE MULTILEVEL CONVERTERS FOR TRACTION SYSTEMS 50Hz / 16 2/3 Hz
By N. Schibli; A. Rufer [View]
[Download]

Abstract: For high power applications, multilevel topologies provide a number of advantages. In this paper, the single- and three-phased multilevel converter is presented. Modulation methods and control schemes have been developed and tested on low-power prototypes. Further development has been made on the key components like the DC/DC converter for the power supplies of each level and on the medium-frequency transformer for the DC/DC converter.

   A NEW APPROACH IN MULTILEVEL POWER CONVERSION
By A. Damiano; M. Fracchia; M. Marchesoni; I. Marongiu [View]
[Download]

Abstract: A novel approach in multilevel power conversion is proposed, that permits the improvement of the voltage/current waveforms if compared to those obtained from conventional multi level converters. This approach is based on the use of power semiconductor devices with different voltage ratings and allows the optimization of their switching stresses. Both the approaches, that derive from the Multi Point Clamped (MPC) concept and from the series connection of H-bridge inverters, are here presented. The modulation strategies that have been developed and the results which have been obtained are presented and discussed.

EPE 1997 – 78: Dialogue Session DS2a: MULTILEVEL AND MATRIX CONVERTERS
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1997 - Conference > EPE 1997 – 78: Dialogue Session DS2a: MULTILEVEL AND MATRIX CONVERTERS
	[return to parent folder]

	THREE-PHASE THREE-LEVEL VOLTAGE-SOURCE CONVERTERS COUPLED WITH HARMONIC CANCELING INTERPHASE REACTORS By K. Oguchi; N. Nakajima; T. Sano	[View] [Download]
Abstract: For high power applications, double three-level voltage-source converters coupled with harmonic canceling interphase reactors are proposed. A voltage wave notching method is applied to control fundamental voltages and eliminate two or four lower harmonic components. The increased harmonic components due to the notching can be canceled by the harmonic canceling reactors. Thus, the proposed system can produce relatively less distorted m put current waveforms at lower switching frequencies.

	STABILITY ANALYSIS OF MULTILEVEL CONVERTERS WITH IMBRICATED CELLS By J.L. Duarte; P.J.M. Julicher; L.J.J. Offringa; W.D.H. van Groningen	[View] [Download]
Abstract: By taking the influence of parasitic components explicitly into account, a small signal sampled-data description of a multilevel converter with imbricated cells is derived. Instead of stressing numerical solutions, the derivations are worked out following an analytical formulation. Although attention is paid to a three-level chopper, the modelling approach is appropriate to other multilevel converters as well. Simulation results and experimental measurements confirm the validity of the proposed model.

	FIVE LEVEL LABORATORY VAR COMPENSATOR WITH SEPARATED FLOATING DC VOLTAGES By T. W. Rasmussen	[View] [Download]
Abstract: The paper discusses an IGBT model of a 10 kvar five level nonclamped compensator built to investigate multilevel system principles. Pulse wide modulation with selective harmonic elimination for multilevel converters is described where one of the solutions is made in the laboratory model. Also the d.c. voltage sharing between the capacitors from the model is shown and methods for this regulation is given.

	CONTROL STRATEGY FOR MULTILEVEL CONVERTER APPLIED FOR ELECTRIC POWER SYSTEM By Noriyuki Kimura; Akira Matsumoto; Toshimitsu Morizane; Katsunori Taniguchi	[View] [Download]
Abstract: Multilevel converter using GTO thyristor can reduce higher harmonics without increasing switching frequency and loss. However, keeping dc capacitance voltage is difficult for fundamental frequency switching single converter. This paper discusses the cause of unbalance of dc capacitor voltage and propose double converter configuration for the solution.

	SERIAL CONNECTION : SOFT SWITCHING, A WAY TO REDUCE PARASITIC OVERCURRENTS By N. LAPASSAT; D. CHATROUX; D. LAFORE	[View] [Download]
Abstract: This paper describes how soft switching can be used in serial connection of power components in order to reduce overcurrents due to parasitic capacitances to ground during turn on. In hard switching, this phenomenon become crucial when the number of serial connected switches increases. Indeed, the parasitic current in the lowest potential devices increases losses and can even exceed their pulse current rating. Particular attention is given to the way resonant inductors can be placed in series with devices in order to reduce these overcurrents. This makes the achievement of an over 50kV switch easier for the use in high voltage static converter.

	SWITCH-EFFECTIVE MODULATION STRATEGY FOR MATRIX CONVERTERS By Ake Christensson	[View] [Download]
Abstract: This paper describes a modulation strategy for the matrix converter. The proposed method minimises the number of required switchings for each power pulse, while achieving sinusoidal output voltage and sinusoidal input current. The method uses the complex vector approach. A mathematical description of the matrix converter is given. Simulation results as well as measurements from an IGBT-based, 30 kVA experimental prototype are presented.

	A MATRIX CONVERTER SWITCHING CONTROLLER FOR LOW LOSSES OPERATION WITHOUT SNUBBER CIRCUITS By R. Cittadini; J-J. Huselstein; C. Glaize	[View] [Download]
Abstract: A Matrix Converter can reproduce many functions in power electronics. However, this converter is only composed of wholly controlled switches. The resulting specific forced commutation must be cleverly managed. In this paper, we show how to obtain optimal forced commutation in a Matrix Converter without additional stress on power semiconductors and without snubbers. Experimental results of a 3 kVA direct AC/AC single phase converter are reported.

	A 3kW UNIT-POWER-FACTOR MULTILEVEL RECTIFIER BASED ON A DOUBLE-BOOST CONVERTER By P. Bartholoméüs; P. Le Moigne	[View] [Download]
Abstract: This paper presents the study and the tests of a double-boost rectifier working in multilevel operation. The particular working of this new converter is described. Its control process is defined in order to obtain a sinusoidal input current and to balance the DC output voltages. Finally, test comparisons of a 3 kW conventional boost rectifier with a 3-level one present several advantages of the latter and show that this converter is well adapted to high power factor applications.

	SINGLE- AND THREE-PHASE MULTILEVEL CONVERTERS FOR TRACTION SYSTEMS 50Hz / 16 2/3 Hz By N. Schibli; A. Rufer	[View] [Download]
Abstract: For high power applications, multilevel topologies provide a number of advantages. In this paper, the single- and three-phased multilevel converter is presented. Modulation methods and control schemes have been developed and tested on low-power prototypes. Further development has been made on the key components like the DC/DC converter for the power supplies of each level and on the medium-frequency transformer for the DC/DC converter.

	A NEW APPROACH IN MULTILEVEL POWER CONVERSION By A. Damiano; M. Fracchia; M. Marchesoni; I. Marongiu	[View] [Download]
Abstract: A novel approach in multilevel power conversion is proposed, that permits the improvement of the voltage/current waveforms if compared to those obtained from conventional multi level converters. This approach is based on the use of power semiconductor devices with different voltage ratings and allows the optimization of their switching stresses. Both the approaches, that derive from the Multi Point Clamped (MPC) concept and from the series connection of H-bridge inverters, are here presented. The modulation strategies that have been developed and the results which have been obtained are presented and discussed.