EPE Association: EPE 2005 - Topic 02-3a - DS: Passive components, Materials and interconnection methods

EPE 2005 - Topic 02-3a - DS: Passive components, Materials and interconnection methods
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2005 - Conference > EPE 2005 - Topic 02: PASSIVE COMPONENTS, SYSTEM INTEGRATION & PACKAGING > EPE 2005 - Topic 02-3a - DS: Passive components, Materials and interconnection methods

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   A new silicon resistor technology for very high power snubbers
By COVA Paolo; ZANI Pier Enrico; MENOZZI Roberto; PORTESINE Marco; SOZZI Giovanna; PAMPILI Pietro [View]
[Download]

Abstract: In this work we developed press-pack silicon resistors for current ratings of thousands of amperes. Many prototypes were fabricated (with various resistance values) and characterized, using low-voltage (< 100 V) fast-pulsed (i.e., isothermal) measurements to tune a two-dimensional electro-thermal numerical model. The simulations then provided us with a description of the resistor behavior under high-voltage and highcurrent conditions that were unattainable by our measurement set-up. The decrease of carrier mobility with electric field causes a non-linear I-V relationship whereby the resistance is lower at low fields and higher at high fields. This feature is useful in snubber applications, where the resistor is used as a currentlimiting element during the discharge of the capacitor: the resistance is maximum at the onset of the discharge phase, when current must be limited, then its value decreases with the voltage drop, thus speeding up the transient. The simulations also allowed us to study the temperature dependence of the resistance. We observed a non-monotonic behavior, with an increase of the resistance with temperature due to carrier scattering, followed by a rapid decrease due to thermal generation of excess carriers. These press-packed resistors represent a promising solution for snubber application in stacks with high-power diodes or GTOs, very large currents being allowed by the outstanding heat-sinking capabilities of the press-pack.

   A Novel Iron Loss Calculation Method on Power Converters Based on Dynamic Minor Loop
By SHIMIZU Toshihisa; IYASU Seiji; ISHII Kenichiro [View]
[Download]

Abstract: The authors have reported a novel iron loss calculation method based on a loss-map of the magnetic materials. A distinctive feature of this method is that the iron loss on the inductors can easily be calculated in many kinds of converters dynamically. The dynamic measuring method of the dynamic minor-magnetic loop by using the buck-chopper circuit is presented. Next, some typical characteristics of the loss map derived from the dynamic minor loop measurement is discussed. Also, a novel iron loss calculation method of the ac filter inductor on the PWM inverter by using the loss-map method is described.Some experimental results shows that the iron loss obtained from this calculation method coincides well with the actual one.

   ANALYTICAL MODELLING DEDICATED TO INTEGRATED PLANAR PASSIVE COMPONENT
By DAVEAU Guillaume; FAUCHER SeBastien; JOUBERT Charles; FOREST FrançOis [View]
[Download]

Abstract: A method for predicting the stray capacitance of planar inductors with a single layer is presented. The method is based on an analytical approach. First, the model is done for only two conductors and is then extended to a physical structure with several conductors. The modeling results are confronted with finite element method (FEM) simulations as well as with experimental results.

   Assessment of electrothermal model of supercapacitors for railway applications
By ABDERRAHMANE Hammar [View]
[Download]

Abstract: The aim of the SNCF research division program in collaboration with LTN-INRETS laboratory is to respond to the high demand to more environmentally friendly transportation.We have investigated general behaviours of supercapacitors for railway application with two powerful methods of analysis. The first is constant charge/discharge current at high level value (300, 500 A), the second is impedance spectroscopy method.An electrothermal circuit model of supercapacitors based on activated carbon and organic electrolyte is defined for a given railway application. Matlab/Simulink simulations are shown to assess the model under railway specifications.

   Design methodology of very large scale integration fully digital controller for power control
By SAADATE Shahrokh; BRAUN Francis; POURE Philippe [View]
[Download]

Abstract: This paper presents a methodology to design Very Large Scale Integration fully digital controller for Intelli-gent Power control. Step by step, Top-down methodology for virtual prototyping based on Very high speed inte-grated circuits Hardware Description Language-Analog-mixed Signal (VHDL-AMS) with associated mixed simulation tools was used to study digital adaptation and architecture implementation of the control algorithm. Modeling, mixed simulation and virtual prototyping are achieved in an unique design environment. An application using the proposed methodology was studied: a digital controller for a single-phase parallel active power filter. The controller is described and virtual prototyping examined. Analog and digital models were used to de-fine the algorithm implementation, specific binary format and architecture. The Register Transfer Level model for this digital controller was finally validated by mixed simulation.

   Eddy current losses in SMPS transformers round wire windings: a semi-analytical closed-form formula
By ROBERT FreDeRic; MATHYS Pierre; SCHAUWERS Jea; SPROOTEN Jonathan; VELAERTS Bruno [View]
[Download]

Abstract: We provide a new closed-form formula that instantly calculates the 2D high-frequency ohmic losses (skin and proximity effects) in round wire windings. It has been obtained by overwriting the classical definition (shown to be erroneous) of the layer copper factor introduced in 1D analytical theories. Compared to similar previous formulas, the average error is divided by a factor of thousand. Experimental validation is provided.

   Fabrication of an integrated spiral-type inductor dedicated to DC-DC microconverters
By LAUR Jea [View]
[Download]

Abstract: This paper describes the fabrication steps of a spiral-type inductor designed for power electronics conversion. Realized on silicon wafer and using photolithography and electroplating techniques, this microinductor is composed of a copper spiral conductor sandwiched between two iron-nickel laminated magnetic layers. Furthermore, specific devices have been realized in order to characterize the magnetic material.

   Inductors combining ring cores and I cores
By GAO Yuang Feng; VAN DE SYPE David [View]
[Download]

Abstract: Inductors are usually realized with E, I cores and C core types. Some other construction types are also possible, using a combination of I cores and ring cores and cut ring cores. We designate them as OI, CIC, 4I and 6I (hexagonal) cores. We compare their weight for a given copper loss and a given reactive power. Although ring cores with multiple air gap seem the best solution, the optimal inner/outer diameter ratio is much lower than usual, and high copper filling factors are not realistic. The CIC-inductor has also a good performance and uses oriented steel more efficient than in EI-cores, but has no improved heat transfer compared to EI-shapes. The hexagonal inductor type combines a high peak induction, a high filling factor and a good heat transfer to ambient and reduces weight and losses for inductors. To check the design a hexagonal core was constructed. However a drawback might be the tendency to mechanical vibration. Some of the core types may also be useful in ferrite cores.

   Integral design of a high power density DC/DC converter for harsh environments
By HOFSAJER Ivan; SELIGER Norbert; FERREIRA J.; GERBER Mark [View]
[Download]

Abstract: Power electronic systems are finding applications in increasingly demanding environments. This coupled together with demanding converter specifications requires an integral electrical, thermal and spatial design of these power electronic systems. This paper investigates and implements an integral design that identifies the interdependencies between the electrical, thermal and spatial designs of a power electronic converter and considers how the interdependencies can be manipulated to meet all the converter specifications simultaneously in a single volume. The integral design procedure is used to design a 2kW power converter for implementation in the automotive environment. The power converter utilizes the automotive liquid coolant system where the coolant has a maximum temperature of 125°C for heat removal. Under these conditions, the design achieves a power density of 120W/in3 (7.3kW/liter). Practical results confirming the design are presented.

   Integration Methodology for Current Sensing in Inverter Bus Bars using Ultra Compact GMR – Based Point Field Detection
By OLSON Erik [View]
[Download]

Abstract: The latest developments in point field detection for integrated current sensing are discussed. The effects that the skin-effect has on bandwidth and accuracy are explored. Numerical calculations and experimental measurements are performed on conductors with rectangular cross-sections. Point field measurements are made using giant magnetoresistive (GMR) field detectors, and are compared with results from numerical analyses. Two-dimensional finite element models demonstrate the tradeoff between flat measurement bandwidth and field strength as a function of frequency. Optimization functions are used to determine the best placement of the field detector for use as a current sensor.

   PCB embedded DC/DC 42V/14V converter for automotive applications
By FERREIRA Jan Abraham; WAFFENSCHMIDT Eberhard; POPOVIC Jelena [View]
[Download]

Abstract: A DC/DC 42V/14V converter for automotive applications is constructed in an integrated PCB technology. By using integration technologies such as embedded passives into PCB, heat spreading and thermal vias thermal management technologies, the number of construction parts and processes can be reduced thus reducing the cost and size of power electronic converters. Since this technology is limited in power level, a modular arrangement can be employed to achieve desired power levels. Furthermore, the converter is designed in an integral manner, combining electrical, thermal and spatial design in order to satisfy the stringent requirements of the automotive market, in particular those related to the volume and high operating temperature.

   Technological study of a module IGBT for an aeronautical application in zone engine
By LHOMMEAU Tony; MEURET ReGis; KARAMA Moussa [View]
[Download]

Abstract: The non pressurised zones of aeroplanes raise the problem of the choice of power components. The motor nacelle is a non pressurised zone and the IGBT modules are therefore subjected to strong combined constraints: thermal, mechanical (vibrations, shocks), pressure/depression/damp.The power IGBTs are located inside a closed but not airtight box containing the complete inverter (IGBT modules, busbar, capacity, drivers and electronics control). The components are subjected to severe aeronautic constraints. There is wide experience as regards the reinforcements to be added to theelectronic cards in order to meet reliability demands; the choice of the structure and the IGBT module technology has still to be solved.

   The experimental coaxial transformer – technology and characteristics
By MACIAK Erwin; STEPIEN Mariusz; KACZMARCZYK Zbigniew; GRZESIK Boguslaw; ZYGMANOWSKI Marcin [View]
[Download]

Abstract: The experimental coaxial transformer, its idea, novel technology of fabrication and its characteristics are given in the paper. The experimental results are compared with the results obtained from FEM analysis. The described transformer has high efficiency (98\%), high power density (75 kW/kg) and good coupling and small leakage inductances.

   The Minimization of Copper Losses in Core-less Inductors: Application to Foil- and PCB-based Planar Windings
By ALBACH Manfred; STADLER Alexander; MACARY Florence [View]
[Download]

Abstract: Core-less magnetic components have only winding losses and show a much more pronounced size reduction with increasing frequency. Therefore air coils have a size advantage in the MHz range used for energy-storage in switch-mode power supplies. The use of high switching frequencies causes eddy currents in the windings with the consequence of significantly increasing copper losses. The paper describes how to calculate the copper losses of foil-windings using a simple state space model and based on the results, it outlines the possibilities to reduce the winding losses by proper component design.

   The optimization of high frequency operated transformers for resonant converters
By STADLER Alexander; CHROMY Simon; ALBACH Manfred [View]
[Download]

Abstract: In this paper the influence of the winding layout of high frequency operated transformers on the core losses and also on the leakage inductance is investigated and verified by measurements. A method of summation is used which is based on an integral equation for the magnetization and based on these results, some design guidelines are derived in order to optimize these components.

EPE 2005 - Topic 02-3a - DS: Passive components, Materials and interconnection methods
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2005 - Conference > EPE 2005 - Topic 02: PASSIVE COMPONENTS, SYSTEM INTEGRATION & PACKAGING > EPE 2005 - Topic 02-3a - DS: Passive components, Materials and interconnection methods
	[return to parent folder]

	A new silicon resistor technology for very high power snubbers By COVA Paolo; ZANI Pier Enrico; MENOZZI Roberto; PORTESINE Marco; SOZZI Giovanna; PAMPILI Pietro	[View] [Download]
Abstract: In this work we developed press-pack silicon resistors for current ratings of thousands of amperes. Many prototypes were fabricated (with various resistance values) and characterized, using low-voltage (< 100 V) fast-pulsed (i.e., isothermal) measurements to tune a two-dimensional electro-thermal numerical model. The simulations then provided us with a description of the resistor behavior under high-voltage and highcurrent conditions that were unattainable by our measurement set-up. The decrease of carrier mobility with electric field causes a non-linear I-V relationship whereby the resistance is lower at low fields and higher at high fields. This feature is useful in snubber applications, where the resistor is used as a currentlimiting element during the discharge of the capacitor: the resistance is maximum at the onset of the discharge phase, when current must be limited, then its value decreases with the voltage drop, thus speeding up the transient. The simulations also allowed us to study the temperature dependence of the resistance. We observed a non-monotonic behavior, with an increase of the resistance with temperature due to carrier scattering, followed by a rapid decrease due to thermal generation of excess carriers. These press-packed resistors represent a promising solution for snubber application in stacks with high-power diodes or GTOs, very large currents being allowed by the outstanding heat-sinking capabilities of the press-pack.

	A Novel Iron Loss Calculation Method on Power Converters Based on Dynamic Minor Loop By SHIMIZU Toshihisa; IYASU Seiji; ISHII Kenichiro	[View] [Download]
Abstract: The authors have reported a novel iron loss calculation method based on a loss-map of the magnetic materials. A distinctive feature of this method is that the iron loss on the inductors can easily be calculated in many kinds of converters dynamically. The dynamic measuring method of the dynamic minor-magnetic loop by using the buck-chopper circuit is presented. Next, some typical characteristics of the loss map derived from the dynamic minor loop measurement is discussed. Also, a novel iron loss calculation method of the ac filter inductor on the PWM inverter by using the loss-map method is described.Some experimental results shows that the iron loss obtained from this calculation method coincides well with the actual one.

	ANALYTICAL MODELLING DEDICATED TO INTEGRATED PLANAR PASSIVE COMPONENT By DAVEAU Guillaume; FAUCHER SeBastien; JOUBERT Charles; FOREST FrançOis	[View] [Download]
Abstract: A method for predicting the stray capacitance of planar inductors with a single layer is presented. The method is based on an analytical approach. First, the model is done for only two conductors and is then extended to a physical structure with several conductors. The modeling results are confronted with finite element method (FEM) simulations as well as with experimental results.

	Assessment of electrothermal model of supercapacitors for railway applications By ABDERRAHMANE Hammar	[View] [Download]
Abstract: The aim of the SNCF research division program in collaboration with LTN-INRETS laboratory is to respond to the high demand to more environmentally friendly transportation.We have investigated general behaviours of supercapacitors for railway application with two powerful methods of analysis. The first is constant charge/discharge current at high level value (300, 500 A), the second is impedance spectroscopy method.An electrothermal circuit model of supercapacitors based on activated carbon and organic electrolyte is defined for a given railway application. Matlab/Simulink simulations are shown to assess the model under railway specifications.

	Design methodology of very large scale integration fully digital controller for power control By SAADATE Shahrokh; BRAUN Francis; POURE Philippe	[View] [Download]
Abstract: This paper presents a methodology to design Very Large Scale Integration fully digital controller for Intelli-gent Power control. Step by step, Top-down methodology for virtual prototyping based on Very high speed inte-grated circuits Hardware Description Language-Analog-mixed Signal (VHDL-AMS) with associated mixed simulation tools was used to study digital adaptation and architecture implementation of the control algorithm. Modeling, mixed simulation and virtual prototyping are achieved in an unique design environment. An application using the proposed methodology was studied: a digital controller for a single-phase parallel active power filter. The controller is described and virtual prototyping examined. Analog and digital models were used to de-fine the algorithm implementation, specific binary format and architecture. The Register Transfer Level model for this digital controller was finally validated by mixed simulation.

	Eddy current losses in SMPS transformers round wire windings: a semi-analytical closed-form formula By ROBERT FreDeRic; MATHYS Pierre; SCHAUWERS Jea; SPROOTEN Jonathan; VELAERTS Bruno	[View] [Download]
Abstract: We provide a new closed-form formula that instantly calculates the 2D high-frequency ohmic losses (skin and proximity effects) in round wire windings. It has been obtained by overwriting the classical definition (shown to be erroneous) of the layer copper factor introduced in 1D analytical theories. Compared to similar previous formulas, the average error is divided by a factor of thousand. Experimental validation is provided.

	Fabrication of an integrated spiral-type inductor dedicated to DC-DC microconverters By LAUR Jea	[View] [Download]
Abstract: This paper describes the fabrication steps of a spiral-type inductor designed for power electronics conversion. Realized on silicon wafer and using photolithography and electroplating techniques, this microinductor is composed of a copper spiral conductor sandwiched between two iron-nickel laminated magnetic layers. Furthermore, specific devices have been realized in order to characterize the magnetic material.

	Inductors combining ring cores and I cores By GAO Yuang Feng; VAN DE SYPE David	[View] [Download]
Abstract: Inductors are usually realized with E, I cores and C core types. Some other construction types are also possible, using a combination of I cores and ring cores and cut ring cores. We designate them as OI, CIC, 4I and 6I (hexagonal) cores. We compare their weight for a given copper loss and a given reactive power. Although ring cores with multiple air gap seem the best solution, the optimal inner/outer diameter ratio is much lower than usual, and high copper filling factors are not realistic. The CIC-inductor has also a good performance and uses oriented steel more efficient than in EI-cores, but has no improved heat transfer compared to EI-shapes. The hexagonal inductor type combines a high peak induction, a high filling factor and a good heat transfer to ambient and reduces weight and losses for inductors. To check the design a hexagonal core was constructed. However a drawback might be the tendency to mechanical vibration. Some of the core types may also be useful in ferrite cores.

	Integral design of a high power density DC/DC converter for harsh environments By HOFSAJER Ivan; SELIGER Norbert; FERREIRA J.; GERBER Mark	[View] [Download]
Abstract: Power electronic systems are finding applications in increasingly demanding environments. This coupled together with demanding converter specifications requires an integral electrical, thermal and spatial design of these power electronic systems. This paper investigates and implements an integral design that identifies the interdependencies between the electrical, thermal and spatial designs of a power electronic converter and considers how the interdependencies can be manipulated to meet all the converter specifications simultaneously in a single volume. The integral design procedure is used to design a 2kW power converter for implementation in the automotive environment. The power converter utilizes the automotive liquid coolant system where the coolant has a maximum temperature of 125°C for heat removal. Under these conditions, the design achieves a power density of 120W/in3 (7.3kW/liter). Practical results confirming the design are presented.

	Integration Methodology for Current Sensing in Inverter Bus Bars using Ultra Compact GMR – Based Point Field Detection By OLSON Erik	[View] [Download]
Abstract: The latest developments in point field detection for integrated current sensing are discussed. The effects that the skin-effect has on bandwidth and accuracy are explored. Numerical calculations and experimental measurements are performed on conductors with rectangular cross-sections. Point field measurements are made using giant magnetoresistive (GMR) field detectors, and are compared with results from numerical analyses. Two-dimensional finite element models demonstrate the tradeoff between flat measurement bandwidth and field strength as a function of frequency. Optimization functions are used to determine the best placement of the field detector for use as a current sensor.

	PCB embedded DC/DC 42V/14V converter for automotive applications By FERREIRA Jan Abraham; WAFFENSCHMIDT Eberhard; POPOVIC Jelena	[View] [Download]
Abstract: A DC/DC 42V/14V converter for automotive applications is constructed in an integrated PCB technology. By using integration technologies such as embedded passives into PCB, heat spreading and thermal vias thermal management technologies, the number of construction parts and processes can be reduced thus reducing the cost and size of power electronic converters. Since this technology is limited in power level, a modular arrangement can be employed to achieve desired power levels. Furthermore, the converter is designed in an integral manner, combining electrical, thermal and spatial design in order to satisfy the stringent requirements of the automotive market, in particular those related to the volume and high operating temperature.

	Technological study of a module IGBT for an aeronautical application in zone engine By LHOMMEAU Tony; MEURET ReGis; KARAMA Moussa	[View] [Download]
Abstract: The non pressurised zones of aeroplanes raise the problem of the choice of power components. The motor nacelle is a non pressurised zone and the IGBT modules are therefore subjected to strong combined constraints: thermal, mechanical (vibrations, shocks), pressure/depression/damp.The power IGBTs are located inside a closed but not airtight box containing the complete inverter (IGBT modules, busbar, capacity, drivers and electronics control). The components are subjected to severe aeronautic constraints. There is wide experience as regards the reinforcements to be added to theelectronic cards in order to meet reliability demands; the choice of the structure and the IGBT module technology has still to be solved.

	The experimental coaxial transformer – technology and characteristics By MACIAK Erwin; STEPIEN Mariusz; KACZMARCZYK Zbigniew; GRZESIK Boguslaw; ZYGMANOWSKI Marcin	[View] [Download]
Abstract: The experimental coaxial transformer, its idea, novel technology of fabrication and its characteristics are given in the paper. The experimental results are compared with the results obtained from FEM analysis. The described transformer has high efficiency (98\%), high power density (75 kW/kg) and good coupling and small leakage inductances.

	The Minimization of Copper Losses in Core-less Inductors: Application to Foil- and PCB-based Planar Windings By ALBACH Manfred; STADLER Alexander; MACARY Florence	[View] [Download]
Abstract: Core-less magnetic components have only winding losses and show a much more pronounced size reduction with increasing frequency. Therefore air coils have a size advantage in the MHz range used for energy-storage in switch-mode power supplies. The use of high switching frequencies causes eddy currents in the windings with the consequence of significantly increasing copper losses. The paper describes how to calculate the copper losses of foil-windings using a simple state space model and based on the results, it outlines the possibilities to reduce the winding losses by proper component design.

	The optimization of high frequency operated transformers for resonant converters By STADLER Alexander; CHROMY Simon; ALBACH Manfred	[View] [Download]
Abstract: In this paper the influence of the winding layout of high frequency operated transformers on the core losses and also on the leakage inductance is investigated and verified by measurements. A method of summation is used which is based on an integral equation for the magnetization and based on these results, some design guidelines are derived in order to optimize these components.