EPE Association: EPE 1999 - Topic 01a: Passive Components

EPE 1999 - Topic 01a: Passive Components
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1999 - Conference > EPE 1999 - Topic 01: DEVICES > EPE 1999 - Topic 01a: Passive Components

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   A Simple and Efficient Optimization Routine for Design of High Fr...
By S. Farhangi; A-A. Shayegan Akmal [View]
[Download]

Abstract: An efficient, meanwhile simple optimization routine is presented for design of high frequency power transformers. Minimizing the product of power loss, core cross section and winding area is chosen as the optimization goal. This object function leads to a closed form solution, which reduces the computation time and the number of iterations. A CAD tool has been developed according to this method, which is addressed in this paper. By this tool the optimized core which fulfills the temperature rise constraint is determined. If the area product of the selected core is bigger than the optimum area product, the user can modify his design further by minimizing the power loss. The validation of the method is verified by a sample design example.

   Advanced Guidelines and Optimization Tools for Foil Conductors De...
By F. Robert; P. Mathys; J-P. Schauwens [View]
[Download]

Abstract: This paper deals with 2D ohmic losses calculation in SPMS transformers foil conductors. The effect of each geometrical design parameter on the losses is clearly identified by analyzing the results of a semi-empirical formula which we have developed. More accurate design rules and optimization tools are presented to designers.

   Advanced IGBT Converters with 4.5kV and 6.5kV Semiconductor Devices
By R. Marquardt; G. Papp; J. Teigelkötter [View]
[Download]

Abstract: The IGBT has become the dominating power semiconductor over the whole blocking voltage range from 600 V to 3300V. The "mainstream" of applications in this range is characterized by the following items: a) Hard switching without snubbers, b) Module package with internal insulation, c) Integrated free wheeling diode. Focused on future high voltage (4.5kV and 6.5kV IGBT) devices and the high power requirements of main line locomotives and high speed trains, these typical application conditions have been thorougly studied and compared to other possible converter concepts. The main points of investigation were: a) Semiconductor optimization with respect to minimal losses and high reliability, b) Increased output power without parallel or series connection, c) Weight, volume and cost reduction, d) Compatibility to motor and line side, e) Protection of the equipment under severe fault conditions. In this paper, the results of these investigations are presented. They show that for the aspired high voltage / high power range a superior converter concept - named small snubber concept (SSC) - is feasible. It compares favorable to both GTO-Converters and present IGBT-Converters. The development of the devices and the converters for the 4.5 kV-level has succesfully reached the prototype status. The first high performance 6.4MW-locomotive (No. 190 of the series BR 152 of the German Railways) fully equipped with this IGBT-converter type is running in regular service since December 1998. Converters with 6.5 kV-devices for application in multisystem locomotives are under development.

   Air-Core Transformer for High Frequency Power Conversion
By K.W.E. Cheng; H.L. Chan; D. Sutanto [View]
[Download]

Abstract: This paper presents a concept of air-core transformer using superconducting and self-resonant techniques. Experimental results will be used to verify the theoretical prediction. This transformer is important for future conversion and its advantages includes elimination of the core, reduction the power loss and elimination the danger of core saturation.

   Analysis of AC Resistance in Aluminium Foil Air Cored Inductors
By N. Williams; C. Pollock [View]
[Download]

Abstract: The measurement and analysis of turn to turn potential difference in a typical foil wound inductor is presented. The technique is discussed in relation to the observed rapid increase of ac resistance with frequency in this type of inductor. The distribution of current within the device is also considered.

   Development of a New Technology for Inductive Device Applications
By E. Belloy; O. Dezuari; S. E. Gilbert; M.A.M. Gijs [View]
[Download]

Abstract: We describe the fabrication and characterization of 2-dimensional inductive devices integrated inside printed circuit boards (PCB) and flex-foils. Our devices basically are composed of three layers of which the outer layers bear the printed coil patterns and the inner layer is a high permeability ferromagnetic sheet core. Both magnetic metal and copper layers are patterned using standard lithographic techniques. Electroplated interconnects between the outer layers complete the windings. We have fabricated both transformers and fluxgate magnetic field sensing devices with a thickness of 200 um for the flex-foil devices and 600 um for the PCB-based devices. Materal dimensions are approximately 1 cm. We realise a magnetic field detection limit of 43 uT at 20 kHz for the fluxgate devices relatively and inductances of 1-10 uH at a frequency of 1 kHz for the transformers. Application of our devices is in magnetic field and current sensing and in low power electronics, where miniaturisation is an issue.

   From Modeling of Magnetic Components to Simulation of Converters
By D. Ligot; J-J. Rousseau; B. Allard; H. Morel; D. Renault [View]
[Download]

Abstract: Literature provides few papers about magnetic component models that include the media non linearities and the power losses estimation. Thus we propose a new approach based on bond graphs. The obtained model is suitable for circuit simulation and gives good results. An application to the flyback converter is presented.

   Implementation of a Knowledge-Based System for Inductor Design
By A. R. Sadeghian; J. D. Lavers [View]
[Download]

Abstract: This paper presents the implementation of a Knowledge-Based System that undertakes the design of an inductor. The key issues relating to the implementation of such a system are identified. A recursive design methodology, based om imitating human expert designer and suitable for embedding in the Knowledge-Based System, is employed. A hybrid knowledge base, using both frame-based and rule-based paradigms, together with assertions and procedural attachment, is then created to capture inductor oriented design expertise. Results are presented that illustrate the performance of the developed system, particularly in comparison to the standard design procedure found in the literature.

   Investigation of High Power Bus Bars by Transient Numberical Analysis
By P. Böhm; J. Sigg; G. Wachutka [View]
[Download]

Abstract: The frequency of converters increases steadily due to considerable progress recently made on major power components. Shortening switching times requires steeper current and voltage gradients. Thus the distributed parasitic effects of the wiring are becoming more and more important for the performance of power electronic systems. In order to evaluate the influence of the time-dependent electromagnetic behaviour of bus bar structures in high power modules, a practical methodology for the analysis of distributed parasitic effects has been developed. Its capability is tested by analysing the gate drive unit of hard driven GTOs. It is shown that a comprehensive evaluation can only be done by a full three-dimensional transient simulation of the entire circuit under realistic switching conditions.

   Layer Based Capacitance Model for Magnetic Devices
By T. Duerbaum [View]
[Download]

Abstract: Magnetic components are essential for switched-mode power supplies. The designer has to understand the parasitic behaviour of these non-standard devices. Besides the losses and the leakage inductances a model should include the capacitive behaviour. the flat model describes the electrostatics of magnetics consisting of two layers. This paper demonstrates the extension towards an arbitrary number of layers.

   New Etching - Electroplating Technology for Quality Factor Enhancement of inductive devices
By E. Belloy; M.A.M. Gijs [View]
[Download]

Abstract: We have studied a new technique for the realisation of inductive devices with an enhanced electrical quality factor. the technique consists in the etching and subsequent electroplating of Cu coils with very high Cu filling, typically leading to a doubling of the quality factor, when compared to a non-electroplated sample. We have extensively characterised the geometrical properties of the coil winding patterns as a function of electroplating current and have measured the inductance, Ohmic resistance and quality factor versus frequency. The method works well below frequencies of about 0.1 - 1 MHz; at higher frequencies, both eddy current losses and capacitive coupling lead to a decreasing quality factor for the electroplated devices.

   Three-winding Transformer Suitable for Power Electronics Simulation
By A. Schellmanns; J.L. Schanen; J.P. Keradec [View]
[Download]

Abstract: In most modern power electronic devices, transformers are used to transfer energy and they appear as a key point of switching power supplies. In this paper, the role of transformer in EMI generation is underlined. Owing to a new understanding of magnetic and electrostatic coupling, a successive refinement method is presented. The influence of different transformer models on both power waveform and EMC behaviour is studied. Simulations with these models are compared with measurement acquired on an industrial flyback converter using a three-winding transformer.

EPE 1999 - Topic 01a: Passive Components
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1999 - Conference > EPE 1999 - Topic 01: DEVICES > EPE 1999 - Topic 01a: Passive Components
	[return to parent folder]

	A Simple and Efficient Optimization Routine for Design of High Fr... By S. Farhangi; A-A. Shayegan Akmal	[View] [Download]
Abstract: An efficient, meanwhile simple optimization routine is presented for design of high frequency power transformers. Minimizing the product of power loss, core cross section and winding area is chosen as the optimization goal. This object function leads to a closed form solution, which reduces the computation time and the number of iterations. A CAD tool has been developed according to this method, which is addressed in this paper. By this tool the optimized core which fulfills the temperature rise constraint is determined. If the area product of the selected core is bigger than the optimum area product, the user can modify his design further by minimizing the power loss. The validation of the method is verified by a sample design example.

	Advanced Guidelines and Optimization Tools for Foil Conductors De... By F. Robert; P. Mathys; J-P. Schauwens	[View] [Download]
Abstract: This paper deals with 2D ohmic losses calculation in SPMS transformers foil conductors. The effect of each geometrical design parameter on the losses is clearly identified by analyzing the results of a semi-empirical formula which we have developed. More accurate design rules and optimization tools are presented to designers.

	Advanced IGBT Converters with 4.5kV and 6.5kV Semiconductor Devices By R. Marquardt; G. Papp; J. Teigelkötter	[View] [Download]
Abstract: The IGBT has become the dominating power semiconductor over the whole blocking voltage range from 600 V to 3300V. The "mainstream" of applications in this range is characterized by the following items: a) Hard switching without snubbers, b) Module package with internal insulation, c) Integrated free wheeling diode. Focused on future high voltage (4.5kV and 6.5kV IGBT) devices and the high power requirements of main line locomotives and high speed trains, these typical application conditions have been thorougly studied and compared to other possible converter concepts. The main points of investigation were: a) Semiconductor optimization with respect to minimal losses and high reliability, b) Increased output power without parallel or series connection, c) Weight, volume and cost reduction, d) Compatibility to motor and line side, e) Protection of the equipment under severe fault conditions. In this paper, the results of these investigations are presented. They show that for the aspired high voltage / high power range a superior converter concept - named small snubber concept (SSC) - is feasible. It compares favorable to both GTO-Converters and present IGBT-Converters. The development of the devices and the converters for the 4.5 kV-level has succesfully reached the prototype status. The first high performance 6.4MW-locomotive (No. 190 of the series BR 152 of the German Railways) fully equipped with this IGBT-converter type is running in regular service since December 1998. Converters with 6.5 kV-devices for application in multisystem locomotives are under development.

	Air-Core Transformer for High Frequency Power Conversion By K.W.E. Cheng; H.L. Chan; D. Sutanto	[View] [Download]
Abstract: This paper presents a concept of air-core transformer using superconducting and self-resonant techniques. Experimental results will be used to verify the theoretical prediction. This transformer is important for future conversion and its advantages includes elimination of the core, reduction the power loss and elimination the danger of core saturation.

	Analysis of AC Resistance in Aluminium Foil Air Cored Inductors By N. Williams; C. Pollock	[View] [Download]
Abstract: The measurement and analysis of turn to turn potential difference in a typical foil wound inductor is presented. The technique is discussed in relation to the observed rapid increase of ac resistance with frequency in this type of inductor. The distribution of current within the device is also considered.

	Development of a New Technology for Inductive Device Applications By E. Belloy; O. Dezuari; S. E. Gilbert; M.A.M. Gijs	[View] [Download]
Abstract: We describe the fabrication and characterization of 2-dimensional inductive devices integrated inside printed circuit boards (PCB) and flex-foils. Our devices basically are composed of three layers of which the outer layers bear the printed coil patterns and the inner layer is a high permeability ferromagnetic sheet core. Both magnetic metal and copper layers are patterned using standard lithographic techniques. Electroplated interconnects between the outer layers complete the windings. We have fabricated both transformers and fluxgate magnetic field sensing devices with a thickness of 200 um for the flex-foil devices and 600 um for the PCB-based devices. Materal dimensions are approximately 1 cm. We realise a magnetic field detection limit of 43 uT at 20 kHz for the fluxgate devices relatively and inductances of 1-10 uH at a frequency of 1 kHz for the transformers. Application of our devices is in magnetic field and current sensing and in low power electronics, where miniaturisation is an issue.

	From Modeling of Magnetic Components to Simulation of Converters By D. Ligot; J-J. Rousseau; B. Allard; H. Morel; D. Renault	[View] [Download]
Abstract: Literature provides few papers about magnetic component models that include the media non linearities and the power losses estimation. Thus we propose a new approach based on bond graphs. The obtained model is suitable for circuit simulation and gives good results. An application to the flyback converter is presented.

	Implementation of a Knowledge-Based System for Inductor Design By A. R. Sadeghian; J. D. Lavers	[View] [Download]
Abstract: This paper presents the implementation of a Knowledge-Based System that undertakes the design of an inductor. The key issues relating to the implementation of such a system are identified. A recursive design methodology, based om imitating human expert designer and suitable for embedding in the Knowledge-Based System, is employed. A hybrid knowledge base, using both frame-based and rule-based paradigms, together with assertions and procedural attachment, is then created to capture inductor oriented design expertise. Results are presented that illustrate the performance of the developed system, particularly in comparison to the standard design procedure found in the literature.

	Investigation of High Power Bus Bars by Transient Numberical Analysis By P. Böhm; J. Sigg; G. Wachutka	[View] [Download]
Abstract: The frequency of converters increases steadily due to considerable progress recently made on major power components. Shortening switching times requires steeper current and voltage gradients. Thus the distributed parasitic effects of the wiring are becoming more and more important for the performance of power electronic systems. In order to evaluate the influence of the time-dependent electromagnetic behaviour of bus bar structures in high power modules, a practical methodology for the analysis of distributed parasitic effects has been developed. Its capability is tested by analysing the gate drive unit of hard driven GTOs. It is shown that a comprehensive evaluation can only be done by a full three-dimensional transient simulation of the entire circuit under realistic switching conditions.

	Layer Based Capacitance Model for Magnetic Devices By T. Duerbaum	[View] [Download]
Abstract: Magnetic components are essential for switched-mode power supplies. The designer has to understand the parasitic behaviour of these non-standard devices. Besides the losses and the leakage inductances a model should include the capacitive behaviour. the flat model describes the electrostatics of magnetics consisting of two layers. This paper demonstrates the extension towards an arbitrary number of layers.

	New Etching - Electroplating Technology for Quality Factor Enhancement of inductive devices By E. Belloy; M.A.M. Gijs	[View] [Download]
Abstract: We have studied a new technique for the realisation of inductive devices with an enhanced electrical quality factor. the technique consists in the etching and subsequent electroplating of Cu coils with very high Cu filling, typically leading to a doubling of the quality factor, when compared to a non-electroplated sample. We have extensively characterised the geometrical properties of the coil winding patterns as a function of electroplating current and have measured the inductance, Ohmic resistance and quality factor versus frequency. The method works well below frequencies of about 0.1 - 1 MHz; at higher frequencies, both eddy current losses and capacitive coupling lead to a decreasing quality factor for the electroplated devices.

	Three-winding Transformer Suitable for Power Electronics Simulation By A. Schellmanns; J.L. Schanen; J.P. Keradec	[View] [Download]
Abstract: In most modern power electronic devices, transformers are used to transfer energy and they appear as a key point of switching power supplies. In this paper, the role of transformer in EMI generation is underlined. Owing to a new understanding of magnetic and electrostatic coupling, a successive refinement method is presented. The influence of different transformer models on both power waveform and EMC behaviour is studied. Simulations with these models are compared with measurement acquired on an industrial flyback converter using a three-winding transformer.