EPE Association: EPE 2007 - Subtopic 02-3 - DS: Passive components and integrated passive components

EPE 2007 - Subtopic 02-3 - DS: Passive components and integrated passive components
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2007 - Conference > EPE 2007 - Topic 02: 'Passive components, system integration & packaging' > EPE 2007 - Subtopic 02-3 - DS: Passive components and integrated passive components

   [return to parent folder]

   A new modeling approach for circular spiral inductors
By ALONSO Corinne; ARTILLAN Philippe; ESTIBALS Bruno [View]
[Download]

Abstract: This work proposes a new modeling approach for spiral inductive components which is based on the Partial Element Equivalent Circuit (PEEC) method extended to rotational symmetry case. In this context, analytic approximations of all integral formulas are proposed in order to reduce computing time for simulations of the partial inductance and capacitance coefficients with satisfying accuracy. Globally, this approach provides an efficient tool for inductive components design. A full modeling method providing the complex impedance frequency response is illustrated through examples on power applications. An illustration is also given on the ability of the model to show the charge and current densities distribution in conductors. The limits of the present model in terms of capacitive effects modeling are discussed and perspectives of evolution are focused on.

   Comparing piezoelectric transformer working with PLL and with non-linear load approaches in DC-DC converter
By MINAZARA Ericka; COSTA Francois; VASIC Dejan [View]
[Download]

Abstract: A current trend in power electronics is the integration of power supplies. In this field, electromagnetic transformers may be replaced by piezoelectric transformers (PT). In a PT, the input electrical energy is transferred to the output through a mechanical wave using the direct and converse effects of piezoelectric materials. It has been proved that PT exhibit suitable characteristic, good integration capability and several advantages (high insulation, gain ), but it also shows the difficulty to work with variable load. It is very difficult to make it functioning at its maximum power point because the resonance frequency, which corresponds to a maximum power, depends strongly on the load. In this paper, two methods of Maximum Power Point Tracking (MPPT) are presented: the first one is the classical method of frequency regulation with a Phase Locked Loop (PLL), and the second one is a new method, it is based on a phase regulation between the output voltage and the mechanical vibration velocity of the PT. This is an innovative non-linear processing technique derived from the so-called synchronized switch damping technique (SSD) that was developed to address the structural damping problem. A comparison of the performances of these two kinds of MPPT is presented. The study and comparisons are carried out with the same transformer in two DC-DC converters.

   Core Losses Measurements in Intercell Transformers for Interleaved Converters
By MEYNARD Thierry; COSTAN Valentin; FOREST FranÃ§ois; LABOURE Eric [View]
[Download]

Abstract: In interleaved converters, the commutation cells can be interconnected by intercell transformers. In this paper we show how a modified sequence of the voltages applied to windings reduces the flux density in the magnetic core branches. Experimental measurements confirm the flux reduction obtained with the modified supply. Thermal measurements were made in order to evaluate the reduction of total core losses when the modified supply is used.

   Integrated design procedure for printed circuit board inductors in DC-to-DC converters
By JACOBS Joep; WAFFENSCHMIDT Eberhard [View]
[Download]

Abstract: A design procedure for a DC-to-DC converter is presented taking the properties of the required inductor type into account. It is applied to a miniaturized 1.4 MHz boost converter with a power range below 1 W using ultra thin printed circuit board integrated inductors. As a result, it is more efficient to operate in the continuous mode, if the used inductor type has an increased AC resistance. The losses could be reduced by 30\% compared to a reference design.

   On the common mode resonant frequency of transformers
By DE HAAN S. W. H.; FERREIRA J. A.; MEURER Evandro [View]
[Download]

Abstract: This paper compare the common mode resonant frequency of different sorts of transformers (planar and E core) using copper foil and Litz wires. These parameters are needed to determine common mode EMI current, where EMI can be reduced at design stage of converters.

   Performance of 3D capacitors integrated on silicon for DC-DC converter applications.
By MAURAN Nicolas; BARY Laurent; BENAZZI Amine; SANCHEZ Jean-Louis; BRUNET Magali; DUBREUIL Pascal [View]
[Download]

Abstract: The integration of passive components on silicon for future DC-DC converters applications is still a challenging area of research. This paper focuses on integrated 3D capacitors with high capacitance density fabricated with microfabrication techniques on silicon and in particular DRIE. The fabricated prototypes were characterised: a capacitance density between 29 and 46 nF/mm was demonstrated up to 800 kHz. An improvement is presented on the equivalent series resistance (ESR), which impedes currently on the component utilisation at higher frequencies.

EPE 2007 - Subtopic 02-3 - DS: Passive components and integrated passive components
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2007 - Conference > EPE 2007 - Topic 02: 'Passive components, system integration & packaging' > EPE 2007 - Subtopic 02-3 - DS: Passive components and integrated passive components
	[return to parent folder]

	A new modeling approach for circular spiral inductors By ALONSO Corinne; ARTILLAN Philippe; ESTIBALS Bruno	[View] [Download]
Abstract: This work proposes a new modeling approach for spiral inductive components which is based on the Partial Element Equivalent Circuit (PEEC) method extended to rotational symmetry case. In this context, analytic approximations of all integral formulas are proposed in order to reduce computing time for simulations of the partial inductance and capacitance coefficients with satisfying accuracy. Globally, this approach provides an efficient tool for inductive components design. A full modeling method providing the complex impedance frequency response is illustrated through examples on power applications. An illustration is also given on the ability of the model to show the charge and current densities distribution in conductors. The limits of the present model in terms of capacitive effects modeling are discussed and perspectives of evolution are focused on.

	Comparing piezoelectric transformer working with PLL and with non-linear load approaches in DC-DC converter By MINAZARA Ericka; COSTA Francois; VASIC Dejan	[View] [Download]
Abstract: A current trend in power electronics is the integration of power supplies. In this field, electromagnetic transformers may be replaced by piezoelectric transformers (PT). In a PT, the input electrical energy is transferred to the output through a mechanical wave using the direct and converse effects of piezoelectric materials. It has been proved that PT exhibit suitable characteristic, good integration capability and several advantages (high insulation, gain ), but it also shows the difficulty to work with variable load. It is very difficult to make it functioning at its maximum power point because the resonance frequency, which corresponds to a maximum power, depends strongly on the load. In this paper, two methods of Maximum Power Point Tracking (MPPT) are presented: the first one is the classical method of frequency regulation with a Phase Locked Loop (PLL), and the second one is a new method, it is based on a phase regulation between the output voltage and the mechanical vibration velocity of the PT. This is an innovative non-linear processing technique derived from the so-called synchronized switch damping technique (SSD) that was developed to address the structural damping problem. A comparison of the performances of these two kinds of MPPT is presented. The study and comparisons are carried out with the same transformer in two DC-DC converters.

	Core Losses Measurements in Intercell Transformers for Interleaved Converters By MEYNARD Thierry; COSTAN Valentin; FOREST FranÃ§ois; LABOURE Eric	[View] [Download]
Abstract: In interleaved converters, the commutation cells can be interconnected by intercell transformers. In this paper we show how a modified sequence of the voltages applied to windings reduces the flux density in the magnetic core branches. Experimental measurements confirm the flux reduction obtained with the modified supply. Thermal measurements were made in order to evaluate the reduction of total core losses when the modified supply is used.

	Integrated design procedure for printed circuit board inductors in DC-to-DC converters By JACOBS Joep; WAFFENSCHMIDT Eberhard	[View] [Download]
Abstract: A design procedure for a DC-to-DC converter is presented taking the properties of the required inductor type into account. It is applied to a miniaturized 1.4 MHz boost converter with a power range below 1 W using ultra thin printed circuit board integrated inductors. As a result, it is more efficient to operate in the continuous mode, if the used inductor type has an increased AC resistance. The losses could be reduced by 30\% compared to a reference design.

	On the common mode resonant frequency of transformers By DE HAAN S. W. H.; FERREIRA J. A.; MEURER Evandro	[View] [Download]
Abstract: This paper compare the common mode resonant frequency of different sorts of transformers (planar and E core) using copper foil and Litz wires. These parameters are needed to determine common mode EMI current, where EMI can be reduced at design stage of converters.

	Performance of 3D capacitors integrated on silicon for DC-DC converter applications. By MAURAN Nicolas; BARY Laurent; BENAZZI Amine; SANCHEZ Jean-Louis; BRUNET Magali; DUBREUIL Pascal	[View] [Download]
Abstract: The integration of passive components on silicon for future DC-DC converters applications is still a challenging area of research. This paper focuses on integrated 3D capacitors with high capacitance density fabricated with microfabrication techniques on silicon and in particular DRIE. The fabricated prototypes were characterised: a capacitance density between 29 and 46 nF/mm was demonstrated up to 800 kHz. An improvement is presented on the equivalent series resistance (ESR), which impedes currently on the component utilisation at higher frequencies.