EPE Association: EPE 1999 - Topic 01f: Thermal Design

EPE 1999 - Topic 01f: Thermal Design
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1999 - Conference > EPE 1999 - Topic 01: DEVICES > EPE 1999 - Topic 01f: Thermal Design

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   A Long Term Test Set-Up for Evaluation of High Power IGBT-Modules
By G. Zaiser; R. Sommer; T. Franke [View]
[Download]

Abstract: This paper describes a new long term test set-up for high power IGBTs. The IGBTs are operating under realistic conditions. The test set-up not only controls the power circuit, but also measures the characteristic parameters of the IGBT modules, including switching losses, saturation voltages, leakage currents and thermal resistances. Results from a long term test of six months of operation under full load are presented. The results show an excellent long-term stability of the high voltage IGBT modules showing that the IGBT is suitable for high reliability drives in traction and industrial applications.

   Analytic Modelling of the Thermal Behaviour of an Air-cored Coil ...
By C.Coillot; Y.Patin; F.Forest; P. Chantrenne [View]
[Download]

Abstract: The studied component, rather simple on electromagnetic viewpoints, is a single layer air cored coil. We lead the calculation of an analytical thermal model based on the physical phenomenon description. Such a model enables us to predict a temperature cartography. Calculation of free convection and radiation are presented under their local and global effects. In fact, the concavity of the internal surface induces a radiation on itself. The radiation model is obtained by using the calculation of radiation exchanges and view factor. Finally, results of the numerical resolution for the analytical model and measures are compared.

   Comparison of Extruded and Bonded Fins Profiles for Optimised Heatsinks
By F. Profumo; S. Facelli; A. Tenconi; B. Passerini [View]
[Download]

Abstract: In this paper the effect of the heatsink profile parameters on the heat transfer efficiency is analysed by means of thermal modelling and of finite element simulations. The proposed analysis evaluates the posibility of optimising the heatsink profile (bounded fin heatsinks) and provides quantified data to help the designers to properly choose the optimum heatsink for a variety of applications, cooling systems and conditions, and other overall design constarints.

   Current and Temperature Distribution in Multi-Chip Modules under Inverter Operation
By T. Franke; G. Zaiser; J. Otto; M. Honsberg-Riedl; R. Sommer [View]
[Download]

Abstract: The paper contains the results of investigations on high voltage IGBT modules actual working in an inverter for traction applications and presents a new approach for the thermal analysis of multichip assemblies. For this, electrical parameters of the system as well as module currents, chip temperatures and their transient behaviour have been monitored under different driving and cooling conditions of the inverter. A specially prepared IGBT-module has been used to investigate the module-inverter interplay. The measured data have been analyzed in detail to separate the different effects which cause a varying temperature distribution. It is pointed out that the well-known temperature redistribution by varying current sharing is dominated significantly by the mutual thermal influence between the IGBT and diode chips. For this purpose a model which is based on the principle of superposition has been built up describing the thermal interference inside the module. Finally, the results are discussed under aspects of reliability pointing out that the mutual thermal influence between several chips of a multichip module can be used as a sensitive measure for the quality of the interface between the module and the heatsink.

   Electrothermal Investigation on Large Power Components and Multichip Power Modules
By P. Tounsi; K. Bellil; J.-M. Dorkel [View]
[Download]

Abstract: A simple on-state electrical model is associated with a true transient 3D heat equation solver (LAASTHERM_T), intended to predict the transient temperature and current distributions in large power components, when the waveform of the load current is known. LAASTHERM_T computes transient temperature distributions over the whole active area of the module, taking into account 3D heat diffusion effects in chips and their common package, using power dissipation given by the electrical model.

   On-Line Calculation of the Chip Temperature of Power Modules in Voltage Source Converters Using the Microcontroller
By R. Krümmer; T. Reimann; G. Berger; J. Petzoldt; L. Lorenz [View]
[Download]

Abstract: This paper shows results of investigation of the static and transient chip temperature of IGBT power modules in voltage source converters. An electrical and thermal model is presented for the implementation in a microcontroller. The calculation of the chip temperature and power losses occurs on-line. The goal is to check these parameters dependent on both, the fundamental frequency of the converter output currents (fout(1)=0...50Hz) and load cycles of the output current. First practical results achieved in a step down converter are shown at different load cycles. The model was verified by measurements with an infrared camera using "open" modules.

   Power Losses Distribution in Inductors for Induction Cooking Appliances
By P. Hernández; F. Monterde; J. M. Burdío; J. R. García; A. Martinez [View]
[Download]

Abstract: Nowadays induction heating is a growing technique in domestic cooking appliances. An important point of these appliances is the high temperature the inductor can reach, due to its own self-heating and the heat transferred from the pot. This work deals with the power losses distribution in the inductor, which can be useful for the designer in order to locate the hot spots inside the inductor and therefore to improve the inductor performance.

   Real-time Thermal Management of Power MOSFETs in a Motor Drive
By C.D. French; P.P.Acarnley; C.M.Johnson [View]
[Download]

Abstract: This paper introduces a closed-loop observer for the real-time estimation of the active junction temperature in a power MOSFET, using measurements of the device electrical terminal quantities: current and on-state voltage. The observer has been implemented using a TMS 320C31 40MHz digital signal processor, which is capable of performing the dual tasks of current control and temperature estimation at the modulation frequency of 8.3kHz. Experimental results verify that the instantaneous temperature of a power device can be monitored throughout the range of operating conditions (conduction and freewheeling) encountered in a variable-frequency variable-voltage converter controlled by pulse width modulation. The effect of modelling errors on the quality of temperature estimates is illustrated. Because modelling errors result in current estimation errors, a measure of modelling error is readily available.

   Standards for Thermal Interface Materials
By H. J. Fick; K. Hanson; L. Ng; B. Schuhbauer [View]
[Download]

Abstract: Electronics assemblies generate waste heat. Emphasis on size, cost, and manufacturing technique leads design engineers to use elegant thermal interface solutions between waste heat generating components and heat sinks. Our industry needs to describe alternate thermal interface materials in a more complete and standardized way. Suppliers have cooperated in development of standard test methods for interface materials. The United States Defense General Supply Center, Richmond Virginia, invited ASTM (American Society for Testing and Materials) and domestic United States thermal interface materials suppliers to participate in development of industrial standards to replace Military standards for thermal interface materials and parts. Existing standards were Mil I 49456A and Mil I 49466. ASTM committee D-09-19 formed two separate task groups. The intent was to generate thermal conductivity test methods and a composite set of property test methods within the supervision and control of the Committee on Electrical and Electronic Insulating Materials. One task group developed standard test methods to measure the thermal resistance and thermal conductivity of thin, conformal thermal interface materials. A second task group agreed to a composite set of test methods for the characterization of most properties of thin, flexible thermal interface materials. The first ASTM task group prepared test method ASTM D 5470-95. Method A of this standard borrows from ASTM E 1225. It is appropriate to measure thin, conformable materials. ASTM D 5470 has demonstrated good laboratory to laboratory correlation in a round robin test demonstration. The second task group prepared ASTM D 6343-98 to collect test methods appropriate for characterization of thermal interface materials. A common set of test methods to measure the characteristics of competing materials has been established.

   Temperature Estimation and Modelling of Power Modules
By D. Bergogne; H. Morel [View]
[Download]

Abstract: A method to characterise the IGBT (Insulated Gate Bipolar Transistor) from a power module to obtain an internal temperature estimator that is used to make a comparison with the electro-thermal model that have been developed. The technique is used to estimate the temperature of an IGBT during normal operation in a power converter and can be applied to validate electro-thermal models.

   Thermal Analysis of Packaged Power Devices
By P.E. Bagnoli; C. Casarosa; E. Dallago; G. Venchi [View]
[Download]

Abstract: An application of the Thermal Resistance Analysis by Induced Transient (TRAIT) method to simulated and real power device packages with a plastic covering is presented. The TRAIT method allows the exact and physically consistent equivalent electrical circuit to be obtained if the thermal system shows an unidirectional heat transfer. In the present case, because of the plastic layer, this hypothesis had not been verified and improvements to the TRAIT analysis were necessary. Analysis of simulated and experimental thermal transients are reported and discussed.

EPE 1999 - Topic 01f: Thermal Design
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1999 - Conference > EPE 1999 - Topic 01: DEVICES > EPE 1999 - Topic 01f: Thermal Design
	[return to parent folder]

	A Long Term Test Set-Up for Evaluation of High Power IGBT-Modules By G. Zaiser; R. Sommer; T. Franke	[View] [Download]
Abstract: This paper describes a new long term test set-up for high power IGBTs. The IGBTs are operating under realistic conditions. The test set-up not only controls the power circuit, but also measures the characteristic parameters of the IGBT modules, including switching losses, saturation voltages, leakage currents and thermal resistances. Results from a long term test of six months of operation under full load are presented. The results show an excellent long-term stability of the high voltage IGBT modules showing that the IGBT is suitable for high reliability drives in traction and industrial applications.

	Analytic Modelling of the Thermal Behaviour of an Air-cored Coil ... By C.Coillot; Y.Patin; F.Forest; P. Chantrenne	[View] [Download]
Abstract: The studied component, rather simple on electromagnetic viewpoints, is a single layer air cored coil. We lead the calculation of an analytical thermal model based on the physical phenomenon description. Such a model enables us to predict a temperature cartography. Calculation of free convection and radiation are presented under their local and global effects. In fact, the concavity of the internal surface induces a radiation on itself. The radiation model is obtained by using the calculation of radiation exchanges and view factor. Finally, results of the numerical resolution for the analytical model and measures are compared.

	Comparison of Extruded and Bonded Fins Profiles for Optimised Heatsinks By F. Profumo; S. Facelli; A. Tenconi; B. Passerini	[View] [Download]
Abstract: In this paper the effect of the heatsink profile parameters on the heat transfer efficiency is analysed by means of thermal modelling and of finite element simulations. The proposed analysis evaluates the posibility of optimising the heatsink profile (bounded fin heatsinks) and provides quantified data to help the designers to properly choose the optimum heatsink for a variety of applications, cooling systems and conditions, and other overall design constarints.

	Current and Temperature Distribution in Multi-Chip Modules under Inverter Operation By T. Franke; G. Zaiser; J. Otto; M. Honsberg-Riedl; R. Sommer	[View] [Download]
Abstract: The paper contains the results of investigations on high voltage IGBT modules actual working in an inverter for traction applications and presents a new approach for the thermal analysis of multichip assemblies. For this, electrical parameters of the system as well as module currents, chip temperatures and their transient behaviour have been monitored under different driving and cooling conditions of the inverter. A specially prepared IGBT-module has been used to investigate the module-inverter interplay. The measured data have been analyzed in detail to separate the different effects which cause a varying temperature distribution. It is pointed out that the well-known temperature redistribution by varying current sharing is dominated significantly by the mutual thermal influence between the IGBT and diode chips. For this purpose a model which is based on the principle of superposition has been built up describing the thermal interference inside the module. Finally, the results are discussed under aspects of reliability pointing out that the mutual thermal influence between several chips of a multichip module can be used as a sensitive measure for the quality of the interface between the module and the heatsink.

	Electrothermal Investigation on Large Power Components and Multichip Power Modules By P. Tounsi; K. Bellil; J.-M. Dorkel	[View] [Download]
Abstract: A simple on-state electrical model is associated with a true transient 3D heat equation solver (LAASTHERM_T), intended to predict the transient temperature and current distributions in large power components, when the waveform of the load current is known. LAASTHERM_T computes transient temperature distributions over the whole active area of the module, taking into account 3D heat diffusion effects in chips and their common package, using power dissipation given by the electrical model.

	On-Line Calculation of the Chip Temperature of Power Modules in Voltage Source Converters Using the Microcontroller By R. Krümmer; T. Reimann; G. Berger; J. Petzoldt; L. Lorenz	[View] [Download]
Abstract: This paper shows results of investigation of the static and transient chip temperature of IGBT power modules in voltage source converters. An electrical and thermal model is presented for the implementation in a microcontroller. The calculation of the chip temperature and power losses occurs on-line. The goal is to check these parameters dependent on both, the fundamental frequency of the converter output currents (fout(1)=0...50Hz) and load cycles of the output current. First practical results achieved in a step down converter are shown at different load cycles. The model was verified by measurements with an infrared camera using "open" modules.

	Power Losses Distribution in Inductors for Induction Cooking Appliances By P. Hernández; F. Monterde; J. M. Burdío; J. R. García; A. Martinez	[View] [Download]
Abstract: Nowadays induction heating is a growing technique in domestic cooking appliances. An important point of these appliances is the high temperature the inductor can reach, due to its own self-heating and the heat transferred from the pot. This work deals with the power losses distribution in the inductor, which can be useful for the designer in order to locate the hot spots inside the inductor and therefore to improve the inductor performance.

	Real-time Thermal Management of Power MOSFETs in a Motor Drive By C.D. French; P.P.Acarnley; C.M.Johnson	[View] [Download]
Abstract: This paper introduces a closed-loop observer for the real-time estimation of the active junction temperature in a power MOSFET, using measurements of the device electrical terminal quantities: current and on-state voltage. The observer has been implemented using a TMS 320C31 40MHz digital signal processor, which is capable of performing the dual tasks of current control and temperature estimation at the modulation frequency of 8.3kHz. Experimental results verify that the instantaneous temperature of a power device can be monitored throughout the range of operating conditions (conduction and freewheeling) encountered in a variable-frequency variable-voltage converter controlled by pulse width modulation. The effect of modelling errors on the quality of temperature estimates is illustrated. Because modelling errors result in current estimation errors, a measure of modelling error is readily available.

	Standards for Thermal Interface Materials By H. J. Fick; K. Hanson; L. Ng; B. Schuhbauer	[View] [Download]
Abstract: Electronics assemblies generate waste heat. Emphasis on size, cost, and manufacturing technique leads design engineers to use elegant thermal interface solutions between waste heat generating components and heat sinks. Our industry needs to describe alternate thermal interface materials in a more complete and standardized way. Suppliers have cooperated in development of standard test methods for interface materials. The United States Defense General Supply Center, Richmond Virginia, invited ASTM (American Society for Testing and Materials) and domestic United States thermal interface materials suppliers to participate in development of industrial standards to replace Military standards for thermal interface materials and parts. Existing standards were Mil I 49456A and Mil I 49466. ASTM committee D-09-19 formed two separate task groups. The intent was to generate thermal conductivity test methods and a composite set of property test methods within the supervision and control of the Committee on Electrical and Electronic Insulating Materials. One task group developed standard test methods to measure the thermal resistance and thermal conductivity of thin, conformal thermal interface materials. A second task group agreed to a composite set of test methods for the characterization of most properties of thin, flexible thermal interface materials. The first ASTM task group prepared test method ASTM D 5470-95. Method A of this standard borrows from ASTM E 1225. It is appropriate to measure thin, conformable materials. ASTM D 5470 has demonstrated good laboratory to laboratory correlation in a round robin test demonstration. The second task group prepared ASTM D 6343-98 to collect test methods appropriate for characterization of thermal interface materials. A common set of test methods to measure the characteristics of competing materials has been established.

	Temperature Estimation and Modelling of Power Modules By D. Bergogne; H. Morel	[View] [Download]
Abstract: A method to characterise the IGBT (Insulated Gate Bipolar Transistor) from a power module to obtain an internal temperature estimator that is used to make a comparison with the electro-thermal model that have been developed. The technique is used to estimate the temperature of an IGBT during normal operation in a power converter and can be applied to validate electro-thermal models.

	Thermal Analysis of Packaged Power Devices By P.E. Bagnoli; C. Casarosa; E. Dallago; G. Venchi	[View] [Download]
Abstract: An application of the Thermal Resistance Analysis by Induced Transient (TRAIT) method to simulated and real power device packages with a plastic covering is presented. The TRAIT method allows the exact and physically consistent equivalent electrical circuit to be obtained if the thermal system shows an unidirectional heat transfer. In the present case, because of the plastic layer, this hypothesis had not been verified and improvements to the TRAIT analysis were necessary. Analysis of simulated and experimental thermal transients are reported and discussed.