EPE Association: EPE 2005 - Topic 02-3b - DS: Components and integrated subsystems - reliability, modelling, simulation and thermal design

EPE 2005 - Topic 02-3b - DS: Components and integrated subsystems - reliability, modelling, simulation and thermal design
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 02-3b - DS: Components and integrated subsystems - reliability, modelling, simulation and thermal design

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   A universal analytic model for planar coils with circular windings close to conductive-permeable foils
By ALBACH Manfred; KOCH Robert; SCHUH Stephan [View]
[Download]

Abstract: For many applications the dimensions of the circuit are important design parameters especially for consumer electronics. In many cases the height of the whole circuit is fixed by the passive components like capacitors, transformers and inductors. So ultra thin planar coils are one of the possibilities for a height reduction. In this paper a universal analytical model for investigating the influence of conductive, permeable foils on the inductance of ultra thin planar coils for power electronics will be introduced and explained in detail. First of all the equations for the magnetic vector potential in the whole circuit are derived. Based on that the final determination of the inductance is easily possible. Finally the equations are verified by measurements.

   Advanced DBC (Direct Bonded Copper) Substrates for High Power and High Voltage Electronics
By EXEL Karl; SCHUL [View]
[Download]

Abstract: Direct bonded copper substrates have been proven for many years as an excellent solution for electrical isolation and thermal management of high power semiconductor modules. The advantages of DBC-substrates are high current carrying capability due to thick copper metallization and a thermal expansion close to the one of silicon at the copper surface due to high bond strength of copper to ceramic. Increasing requirements for thermal performance and partial discharge free behavior of high power modules were driving research to further improve DBC substrates. This paper will present recent developments of partial discharge free and liquid cooled substrates.

   Comparison of Simulation and Measurement of thermal Resistance of surface mounted power packages for high power density ballasts
By FRANK Wolfgang [View]
[Download]

Abstract: The power density of power systems is often dominated by the package of power electronic components. Using smaller packages results in lower cost but also in poorer thermal performance and higher heat sinking effort. However, if one considers general side conditions, it is possible to reach the same thermalperformance even with a smaller package. This paper discusses two methods of defining the thermal junction-ambient resistance and the commonly used wave solder assembly technology. It also describes the test setup and the results of tests done with various packages and transistors.

   Design Consideration for High Output Power Density (OPD) Converter Based on Power-loss Limit Analysis Method
By TAKAO Kazuto; HAYASHI Yusuke; OHASHI Hiromichi; ADACHI Kazuhiro [View]
[Download]

Abstract: Design consideration for a future high output power density converter has been carried out with a power device loss model. The power device loss model has been established by the power-loss limit analysis method which estimates total power loss of semiconductor power devices accurately taking the correlation between circuit stray parameters and device power losses into consideration. An advantage of the design is highly-detailed volume and an output power density of a converter can be estimated quantitatively by using the power device loss model. Optimal configuration of a power converter constructed by conversion circuit part, passive components and a DC-link capacitor was investigated on the thermal problem by the method. Availability of the method was confirmed by the quantitative design of a 3kVA DC-AC converter constructed by a Si-MOSFET and a SiC-Shottky Barrier Diode (SBD) hybrid pair.

   Electrical Characterizations and evaluation of thermo-mechanical stresses of a power module dedicated to high temperature applications
By BONTEMPS Serge; KHATIR Zoubir; MEURET Regis; DUPONT Laurent; PARMENTIER Bernard; LEFEBVRE Stephane [View]
[Download]

Abstract: In avionic area, the trend is to a growing use of power electronics systems. In this context, we will present results concerning test vehicles (power modules) in order to improve a device assembly technology dedicated to be located “on the engine”, in harsh operating conditions with thermal cycling from -50°C to 200°C in the worst case. The paper focuses on failure modes observed under high operating temperature and high temperature cycles, especially ceramic cracks, conchoidal fracture under the copper lead-frame and solder crack initiation. Numerical thermo-mechanical simulations of the assembly allow to understand the origin of the failures and to improve the assembly lifetime under such severe operating conditions. The objectives of the study are to assess the lifetime behaviour of these modules towards both high temperature and thermal cycling effects.

   Impedance Calculation of Integrated Magnetic Components in a Wide Frequency Range
By LABOURE Eric; ARAB Mohand; COSTA FrançOis [View]
[Download]

Abstract: This paper describes a practical method for calculating —prior to construction— the set of frequency dependent impedances of an integrated magnetic component. This electrical model can also directly be used in an accurate power converter simulation. It is based on a one-dimensional electromagnetic formulation, a geometrical description of the device and on magnetic properties of materials. A comparison between data issued from an integrated magnetic component and electrical simulation of the Pspice model is used to illustrate the accuracy and the limitations of such a method. For this device, the results are accurate up to 100MHz. This method provides the foundation for a flexible approach to design and optimize integrated passive components. Using this model, parametric study becomes convenient so that the optimisation of the integrated passive is greatly facilitated.

   Novel lumped-parameter thermal model for electrical systems
By DAJAKU Gurakuq [View]
[Download]

Abstract: The lumped parameter thermal model has been used for a long time for calculating the temperature rises in electrical systems (e.g electrical machines or power electronic systems). As is known, this method is used to solve thermal problems by applying thermal networks, in analogy to electrical circuits. In spite of being popular, generally this method is not applied correctly for elements with distributed heat generation. It is shown that loading the thermal model with the total power losses leads to wrong results. In this paper, a correct lumped-parameter method will be developed and explained.

   Planar Busbar Optimization Regarding Current sharing and Stray Inductance Minimization
By PASTERCZYK Robert J. [View]
[Download]

Abstract: The design of planar busbars as a must part of any present high power high-frequency converter is particularly fine due to all electromagnetic phenomena which can not be easily predicted with appropriate simulation means. Among the numerous constraints which apply to this component, current sharing between all paralleled components (power IGBT modules and capacitors) and stray inductances responsible of both over-voltages and current unbalance are studied in the paper. Based on a dedicated inductive partial elements modeling the cabling rules are conceived and proposed following an optimization process is presented in order to achieve the optimal busbar design.

   Thermal design of converters using discrete power components incorporating an IGBT and a freewheeling diode
By VAN DEN KEYBUS Jeroen; BELMANS Ronnie; NOBELS Tiene [View]
[Download]

Abstract: This paper presents an extension to the common engineering practice of adding a constant thermal resistance to the manufacturer supplied transient thermal impedance from the semiconductor to the package bottom (Zθ,JC) when mounting power components to a heat sink using electrically insulating pads. It is shown that, when those components contain more than one semiconductor, the proposed extension is necessary to avoid underestimation of the semiconductor junction temperatures, allowing an optimal use of the thermal capabilities of the semiconductors. A new, semi-intrusive measurement technique is used to validate this new design procedure with experimental data.

   Thermal design of integrated motor drives for traction applications
By BAUER Stefan E.; TENCONI Alberto; ROSSI Daniele; FARINA Francesco; PROFUMO Francesco [View]
[Download]

Abstract: The thermal design of a Propulsion Integrated Motor Drive is faced in this paper. The system is constituted by a 25 kW switched reluctance motor, a water cooled “square” housing with pipes positioned in the corners and converter devices directly mounted on the housing. Thermal analysis with Finite Element Method software is performed and simulation results are provided to obtain the main guidelines to design the housing as heatsink for both motor and converter.

EPE 2005 - Topic 02-3b - DS: Components and integrated subsystems - reliability, modelling, simulation and thermal design
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 02-3b - DS: Components and integrated subsystems - reliability, modelling, simulation and thermal design
	[return to parent folder]

	A universal analytic model for planar coils with circular windings close to conductive-permeable foils By ALBACH Manfred; KOCH Robert; SCHUH Stephan	[View] [Download]
Abstract: For many applications the dimensions of the circuit are important design parameters especially for consumer electronics. In many cases the height of the whole circuit is fixed by the passive components like capacitors, transformers and inductors. So ultra thin planar coils are one of the possibilities for a height reduction. In this paper a universal analytical model for investigating the influence of conductive, permeable foils on the inductance of ultra thin planar coils for power electronics will be introduced and explained in detail. First of all the equations for the magnetic vector potential in the whole circuit are derived. Based on that the final determination of the inductance is easily possible. Finally the equations are verified by measurements.

	Advanced DBC (Direct Bonded Copper) Substrates for High Power and High Voltage Electronics By EXEL Karl; SCHUL	[View] [Download]
Abstract: Direct bonded copper substrates have been proven for many years as an excellent solution for electrical isolation and thermal management of high power semiconductor modules. The advantages of DBC-substrates are high current carrying capability due to thick copper metallization and a thermal expansion close to the one of silicon at the copper surface due to high bond strength of copper to ceramic. Increasing requirements for thermal performance and partial discharge free behavior of high power modules were driving research to further improve DBC substrates. This paper will present recent developments of partial discharge free and liquid cooled substrates.

	Comparison of Simulation and Measurement of thermal Resistance of surface mounted power packages for high power density ballasts By FRANK Wolfgang	[View] [Download]
Abstract: The power density of power systems is often dominated by the package of power electronic components. Using smaller packages results in lower cost but also in poorer thermal performance and higher heat sinking effort. However, if one considers general side conditions, it is possible to reach the same thermalperformance even with a smaller package. This paper discusses two methods of defining the thermal junction-ambient resistance and the commonly used wave solder assembly technology. It also describes the test setup and the results of tests done with various packages and transistors.

	Design Consideration for High Output Power Density (OPD) Converter Based on Power-loss Limit Analysis Method By TAKAO Kazuto; HAYASHI Yusuke; OHASHI Hiromichi; ADACHI Kazuhiro	[View] [Download]
Abstract: Design consideration for a future high output power density converter has been carried out with a power device loss model. The power device loss model has been established by the power-loss limit analysis method which estimates total power loss of semiconductor power devices accurately taking the correlation between circuit stray parameters and device power losses into consideration. An advantage of the design is highly-detailed volume and an output power density of a converter can be estimated quantitatively by using the power device loss model. Optimal configuration of a power converter constructed by conversion circuit part, passive components and a DC-link capacitor was investigated on the thermal problem by the method. Availability of the method was confirmed by the quantitative design of a 3kVA DC-AC converter constructed by a Si-MOSFET and a SiC-Shottky Barrier Diode (SBD) hybrid pair.

	Electrical Characterizations and evaluation of thermo-mechanical stresses of a power module dedicated to high temperature applications By BONTEMPS Serge; KHATIR Zoubir; MEURET Regis; DUPONT Laurent; PARMENTIER Bernard; LEFEBVRE Stephane	[View] [Download]
Abstract: In avionic area, the trend is to a growing use of power electronics systems. In this context, we will present results concerning test vehicles (power modules) in order to improve a device assembly technology dedicated to be located “on the engine”, in harsh operating conditions with thermal cycling from -50°C to 200°C in the worst case. The paper focuses on failure modes observed under high operating temperature and high temperature cycles, especially ceramic cracks, conchoidal fracture under the copper lead-frame and solder crack initiation. Numerical thermo-mechanical simulations of the assembly allow to understand the origin of the failures and to improve the assembly lifetime under such severe operating conditions. The objectives of the study are to assess the lifetime behaviour of these modules towards both high temperature and thermal cycling effects.

	Impedance Calculation of Integrated Magnetic Components in a Wide Frequency Range By LABOURE Eric; ARAB Mohand; COSTA FrançOis	[View] [Download]
Abstract: This paper describes a practical method for calculating —prior to construction— the set of frequency dependent impedances of an integrated magnetic component. This electrical model can also directly be used in an accurate power converter simulation. It is based on a one-dimensional electromagnetic formulation, a geometrical description of the device and on magnetic properties of materials. A comparison between data issued from an integrated magnetic component and electrical simulation of the Pspice model is used to illustrate the accuracy and the limitations of such a method. For this device, the results are accurate up to 100MHz. This method provides the foundation for a flexible approach to design and optimize integrated passive components. Using this model, parametric study becomes convenient so that the optimisation of the integrated passive is greatly facilitated.

	Novel lumped-parameter thermal model for electrical systems By DAJAKU Gurakuq	[View] [Download]
Abstract: The lumped parameter thermal model has been used for a long time for calculating the temperature rises in electrical systems (e.g electrical machines or power electronic systems). As is known, this method is used to solve thermal problems by applying thermal networks, in analogy to electrical circuits. In spite of being popular, generally this method is not applied correctly for elements with distributed heat generation. It is shown that loading the thermal model with the total power losses leads to wrong results. In this paper, a correct lumped-parameter method will be developed and explained.

	Planar Busbar Optimization Regarding Current sharing and Stray Inductance Minimization By PASTERCZYK Robert J.	[View] [Download]
Abstract: The design of planar busbars as a must part of any present high power high-frequency converter is particularly fine due to all electromagnetic phenomena which can not be easily predicted with appropriate simulation means. Among the numerous constraints which apply to this component, current sharing between all paralleled components (power IGBT modules and capacitors) and stray inductances responsible of both over-voltages and current unbalance are studied in the paper. Based on a dedicated inductive partial elements modeling the cabling rules are conceived and proposed following an optimization process is presented in order to achieve the optimal busbar design.

	Thermal design of converters using discrete power components incorporating an IGBT and a freewheeling diode By VAN DEN KEYBUS Jeroen; BELMANS Ronnie; NOBELS Tiene	[View] [Download]
Abstract: This paper presents an extension to the common engineering practice of adding a constant thermal resistance to the manufacturer supplied transient thermal impedance from the semiconductor to the package bottom (Zθ,JC) when mounting power components to a heat sink using electrically insulating pads. It is shown that, when those components contain more than one semiconductor, the proposed extension is necessary to avoid underestimation of the semiconductor junction temperatures, allowing an optimal use of the thermal capabilities of the semiconductors. A new, semi-intrusive measurement technique is used to validate this new design procedure with experimental data.

	Thermal design of integrated motor drives for traction applications By BAUER Stefan E.; TENCONI Alberto; ROSSI Daniele; FARINA Francesco; PROFUMO Francesco	[View] [Download]
Abstract: The thermal design of a Propulsion Integrated Motor Drive is faced in this paper. The system is constituted by a 25 kW switched reluctance motor, a water cooled “square” housing with pipes positioned in the corners and converter devices directly mounted on the housing. Thermal analysis with Finite Element Method software is performed and simulation results are provided to obtain the main guidelines to design the housing as heatsink for both motor and converter.