The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Michael A. E. Andersen - One of the best experts on this subject based on the ideXlab platform.
-
Self-oscillating galvanic isolated bidirectional Very High Frequency DC-DC converter
2015 IEEE Applied Power Electronics Conference and Exposition (APEC), 2015Co-Authors: Jeppe A. Pedersen, Arnold Knott, Mickey P. Madsen, Michael A. E. AndersenAbstract:This paper describes a galvanic isolated bidirectional Very High Frequency (VHF = 30 MHz - 300MHz) Class-E converter. The reason for increasing the switching Frequency is to minimize the passive components in the converter. To make the converter topology bidirectional the rectifier has to be synchronous. This increases the complexity of the gate drives, which in this paper is solved by using a self-oscillating gate drive. A bidirectional converter has been implemented and is described in this paper; the converter reaches efficiencies above 80% in forward conduction mode and 73.5% in reverse conduction mode. The designed converter operates at a switching Frequency of 35.6 MHz, which is well within the VHF range. The same converter is also implemented with PCB embedded inductors to minimize cost and the physical volume of the total converter.
-
Outphasing control of gallium nitride based Very High Frequency resonant converters
2015 IEEE 16th Workshop on Control and Modeling for Power Electronics (COMPEL), 2015Co-Authors: Mickey P. Madsen, Arnold Knott, Michael A. E. Andersen, David J PerreaultAbstract:In this paper an outphasing modulation control method suitable for line regulation of Very High Frequency resonant converters is described. The pros and cons of several control methods suitable for Very High Frequency resonant converters are described and compared to outphasing modulation. Then the modulation technique is described and the design equations given. Finally a design example is given for a converter consisting of two class E inverters with a lossless combiner and a common half bridge rectifier. It is shown how outphasing modulation can be used for line regulation while insuring equal and purely resistive loading of the inverters. Combined with a proper design of the inverters that, insures they can achieve zero voltage switching across a wide load range, and gallium nitride FETs for the switching devices, this makes it possible to achieve more than 90% efficiency across most of the input voltage range with good line regulation.
-
Evolution of Very High Frequency Power Supplies
IEEE Journal of Emerging and Selected Topics in Power Electronics, 2014Co-Authors: Arnold Knott, Mickey P. Madsen, Toke Meyer Andersen, Peter Kamby, Jeppe A. Pedersen, Milovan Kovacevic, Michael A. E. AndersenAbstract:The ongoing demand for smaller and lighter power supplies is driving the motivation to increase the switching frequencies of power converters. Drastic increases however, come along with new challenges, namely the increase of switching losses in all components. The application of power circuits used in radio Frequency transmission equipment helps to overcome those. However, those circuits were not designed to meet the same requirements as power converters. This paper summarizes the contributions in the recent years in the application of Very High Frequency (VHF) technologies in power electronics, which show the results of the recent advances and describes the remaining challenges. The presented results include a self-oscillating gate drive, air-core inductor optimizations, an offline LED driver with a power density of 8.9 W/cm 3 , and a 120-MHz, 9-W dc powered LED driver with 89% efficiency as well as a bidirectional VHF converter. The challenges to be solved before VHF converters can be used effectively in industrial products are within those three categories: 1) components; 2) circuit architectures; and 3) reliability testing.
-
Very High Frequency half bridge DC/DC converter
2014 IEEE Applied Power Electronics Conference and Exposition - APEC 2014, 2014Co-Authors: Mickey P. Madsen, Arnold Knott, Michael A. E. AndersenAbstract:This paper presents the first, off chip, class DE (resonant half bridge) converter working in the Very High Frequency (VHF) range. The benefits of using half bridge circuits both in the inverter and rectifier part of a VHF resonant dc/dc converter are analyzed and design equations for all components in the power stage are given. The circuit has been simulated to verify the accuracy of the presented equations and an efficiency of 89% has been shown. A prototype has been implemented with self-oscillating resonant gate drives driving the switches. The prototype has been used to drive an LED string and shows an efficiency of 85% at 29 MHz with 130 V input and 13.4 W output. The efficiency was above 82% in the range 110-150 V input with output power between 10.3 W and 16.5 W.
-
Very High Frequency resonant DC/DC converters for LED lighting
2013 Twenty-Eighth Annual IEEE Applied Power Electronics Conference and Exposition (APEC), 2013Co-Authors: Mickey P. Madsen, Arnold Knott, Michael A. E. AndersenAbstract:This paper presents a Very High Frequency DC/DC converter for LED lighting. Several resonant topologies are compared and their usability discussed. At the end the resonant SEPIC converter is chosen based on the achievable power density and total bill of material. Simulations of a 51 MHz converter with 40 V input and 15 V output are made. The simulation shows possibility of achieving efficiency up to 87 % even with a HEXFET Power MOSFET. Three prototypes of the simulated converter are implemented showing good correlation with simulations. The prototypes have efficiencies up to 84 % and power densities up to 8.9 W/cm3 (146 W/in3).
David J Perreault - One of the best experts on this subject based on the ideXlab platform.
-
Outphasing control of gallium nitride based Very High Frequency resonant converters
2015 IEEE 16th Workshop on Control and Modeling for Power Electronics (COMPEL), 2015Co-Authors: Mickey P. Madsen, Arnold Knott, Michael A. E. Andersen, David J PerreaultAbstract:In this paper an outphasing modulation control method suitable for line regulation of Very High Frequency resonant converters is described. The pros and cons of several control methods suitable for Very High Frequency resonant converters are described and compared to outphasing modulation. Then the modulation technique is described and the design equations given. Finally a design example is given for a converter consisting of two class E inverters with a lossless combiner and a common half bridge rectifier. It is shown how outphasing modulation can be used for line regulation while insuring equal and purely resistive loading of the inverters. Combined with a proper design of the inverters that, insures they can achieve zero voltage switching across a wide load range, and gallium nitride FETs for the switching devices, this makes it possible to achieve more than 90% efficiency across most of the input voltage range with good line regulation.
-
optimization of integrated transistors for Very High Frequency dc dc converters
IEEE Transactions on Power Electronics, 2013Co-Authors: A D Sagneri, David I Anderson, David J PerreaultAbstract:This paper presents a method to optimize integrated lateral double-diffused MOSFET transistors for use in Very High Frequency (VHF, 30-300 MHz) dc-dc converters. A transistor model valid at VHF switching frequencies is developed. Device parameters are related to layout geometry and the resulting layout versus loss tradeoffs are illustrated. A method of finding an optimal layout for a given converter application is developed and experimentally verified in a 50-MHz converter, resulting in a 54% reduction in power loss over a hand-optimized device. It is further demonstrated that hot-carrier limits on device safe operating area may be relaxed under soft switching, yielding significant further loss reduction. A device fabricated with 3-μm gate length in 20-V design rules is validated at 35 V, offering reduced parasitic resistance and capacitance, as compared to the 5.5-μm device. Compared to the original design, loss is up to 75% lower in the example application.
-
Evaluation of Magnetic Materials for Very High Frequency Power Applications
IEEE Transactions on Power Electronics, 2012Co-Authors: Yehui Han, G. Cheung, Charles R. Sullivan, David J PerreaultAbstract:This paper investigates the loss characteristics of RF magnetic materials for power conversion applications in the 10 to 100 MHz range. A measurement method is proposed that provides a direct measurement of an inductor quality factor QL as a function of inductor current at RF frequencies, and enables indirect calculation of core loss as a function of flux density. Possible sources of error in measurement and calculation are evaluated and addressed. The proposed method is used to identify loss characteristics of several commercial RF magnetic-core materials. The loss characteristics of these materials, which have not previously been available, are illustrated and compared in tables and figures. The use of the method and data is demonstrated in the design of a magnetic-core inductor, which is applied in a 30-MHz inverter. The results of this paper are thus useful for the design of magnetic components for Very High Frequency applications.
-
Very High Frequency resonant boost converters
IEEE Transactions on Power Electronics, 2009Co-Authors: Robert C N Pilawapodgurski, A D Sagneri, J M Rivas, David I Anderson, David J PerreaultAbstract:This paper presents a resonant boost topology suitable for Very-High-Frequency (VHF, 30-300 MHz) DC-DC power conversion. The proposed design features low device voltage stress, High efficiency over a wide load range, and excellent transient performance. Two experimental prototypes have been built and evaluated. One is a 110-MHz, 23-W converter that uses a High-performance RF lateral DMOSFET. The converter achieves Higher than 87% efficiency at nominal input and output voltages, and maintains good efficiency down to 5% of full load. The second implementation, aimed toward integration, is a 50-MHz, 17-W converter that uses a transistor from a 50-V integrated power process. In addition, two resonant gate drive schemes suitable for VHF operation are presented, both of which provide rapid startup and low-loss operation. Both converters regulate the output using High-bandwidth, on-off hysteretic control, which enables fast transient response and efficient light-load operation. The low energy storage requirements of the converters allow the use of aircore inductors in both designs, thereby eliminating magnetic core loss and introducing the possibility of easy integration.
-
Optimization of transistors for Very High Frequency dc-dc converters
2009 IEEE Energy Conversion Congress and Exposition, 2009Co-Authors: A D Sagneri, David I Anderson, David J PerreaultAbstract:This document presents a method to optimize integrated LDMOS transistors for use in Very High Frequency (VHF, 30-300 MHz) dc-dc converters. A transistor model valid at VHF switching frequencies is developed. Device parameters are related to layout geometry and the resulting layout vs. loss tradeoffs are illustrated. A method of finding an optimal layout for a given converter application is developed and experimentally verified in a 50 MHz converter, resulting in a 35% reduction in power loss over an un-optimized device. It is further demonstrated that hot-carrier limits on device safe operating area may be relaxed under soft switching, yielding significant further loss reduction. A device fabricated with 20-V design rules is validated at 35-V, offering reduced parasitic resistance and capacitance. Compared to the original design, loss is up to 75% lower in the example application.
Solene Derrien - One of the best experts on this subject based on the ideXlab platform.
-
Radar profileur de vent VHF (Very High Frequency) au Centre de Recherches Atmosphériques de Lannemezan.
2011Co-Authors: Solene DerrienAbstract:Antenne du radar profileur de vent VHF (Very High Frequency). Les boîtiers permettent la formation alternative des 5 faisceaux. L'image montre l'antenne co-co (colinéaire-coaxiale) du radar profileur de vent VHF (Very High Frequency) du Centre de Recherches Atmosphériques de Lannemezan. L'antenne est constituée de 2 réseaux de câbles orthogonaux en hauteur (à 1,63 m de hauteur). Le Centre de Recherches Atmosphériques possède 3 profileurs de vent. Le radar VHF (Very High Frequency) est un radar 5 faisceaux fonctionnant à 45 MHz. Il mesure en continu le vent entre 2 km et 16 km de hauteur. Les 5 faisceaux sont formés par déphasage du signal dans l'antenne. Ce radar est intégré au réseau européen E-PROFILE pour l'alimentation des différents modèles de prévision météorologique européens. Le Centre de Recherches Atmosphériques de Lannemezan mesure en continu, à l'aide de 2 radar profileurs et d'un mât instrumenté, le vent du sol jusqu'à 16 km de hauteur: - le mât instrumenté mesure le vent à 15m, 30m, 45m et 60m de hauteur - le radar UHF mesure le vent de 100m à 4 km - le radar VHF mesure le vent de 2 km à 16 km Ces mesures constituent la base des mesures atmosphériques faites au Centre de Recherches Atmosphériques et sur lesquelles de nombreuses campagnes de terrain viennent s'appuyer.
-
Antenne du radar profileur de vent VHF (Very High Frequency).
2009Co-Authors: Solene DerrienAbstract:Antenne du radar profileur de vent VHF (Very High Frequency). Les boîtiers permettent la formation alternative des 5 faisceaux. En arrière plan, le Pic du Midi de Bigorre où se trouve l'observatoire du Pic du Midi. L'image montre l'antenne co-co (colinéaire-coaxiale) du radar profileur de vent VHF (Very High Frequency) du Centre de Recherches Atmosphériques de Lannemezan. L'image permet la visualisation de l'antenne constituée par 2 réseaux de câbles orthogonaux en hauteur (à 1,63 m de hauteur). Le Centre de Recherches Atmosphériques possède 3 profileurs de vent. Le radar VHF (Very High Frequency) est un radar 5 faisceaux fonctionnant à 45 MHz. Il mesure en continu le vent entre 2 km et 16 km de hauteur. Les 5 faisceaux sont formés par déphasage du signal dans l'antenne. Ce radar est intégré au réseau européen E-WINPROF pour l'alimentation des différents modèles de prévision météorologique européens. Le Centre de Recherches Atmosphériques de Lannemezan mesure en continu, à l'aide de 2 radar profileurs et d'un mât instrumenté, le vent du sol jusqu'à 16 km de hauteur: - le mât instrumenté mesure le vent à 15m, 30m, 45m et 60m de hauteur - le radar UHF mesure le vent de 100m à 4 km - le radar VHF mesure le vent de 2 km à 16 km Ces mesures constituent la base des mesures atmosphériques faites au Centre de Recherches Atmosphériques et sur lesquelles de nombreuses campagnes de terrain viennent s'appuyer.
-
Antenne du radar profileur de vent VHF (Very High Frequency) du Centre de Recherches Atmosphériques de Lannemezan.
2009Co-Authors: Solene DerrienAbstract:Antenne du radar profileur de vent VHF (Very High Frequency). Les boîtiers permettent la formation alternative des 5 faisceaux. En arrière plan, le Pic du Midi de Bigorre où se trouve l'observatoire du Pic du Midi. L'image montre l'antenne co-co (colinéaire-coaxiale) du radar profileur de vent VHF (Very High Frequency) du Centre de Recherches Atmosphériques de Lannemezan. L'image permet la visualisation de l'antenne constituée par 2 réseaux de câbles orthogonaux en hauteur (à 1,63 m de hauteur). Le Centre de Recherches Atmosphériques possède 3 profileurs de vent. Le radar VHF (Very High Frequency) est un radar 5 faisceaux fonctionnant à 45 MHz. Il mesure en continu le vent entre 2 km et 16 km de hauteur. Les 5 faisceaux sont formés par déphasage du signal dans l'antenne. Ce radar est intégré au réseau européen E-PROFILE pour l'alimentation des différents modèles de prévision météorologique européens. Le Centre de Recherches Atmosphériques de Lannemezan mesure en continu, à l'aide de 2 radar profileurs et d'un mât instrumenté, le vent du sol jusqu'à 16 km de hauteur: - le mât instrumenté mesure le vent à 15m, 30m, 45m et 60m de hauteur - le radar UHF mesure le vent de 100m à 4 km - le radar VHF mesure le vent de 2 km à 16 km Ces mesures constituent la base des mesures atmosphériques faites au Centre de Recherches Atmosphériques et sur lesquelles de nombreuses campagnes de terrain viennent s'appuyer.
-
Profileur de vent VHF (Very High Frequency)
2006Co-Authors: Solene DerrienAbstract:Les mesures du radar VHF (Very High Frequency) donnent accès à la dynamique atmosphérique de moyenne et grande échelle, dans la colonne troposphérique située au-dessus du radar. Elles permettent notamment d'étudier les systèmes frontaux, l'effet du relief sur l'écoulement atmosphérique, les profils de vent associés aux orages...
Arnold Knott - One of the best experts on this subject based on the ideXlab platform.
-
Fabrication of 3D air-core MEMS inductors for Very-High-Frequency power conversions
Microsystems & Nanoengineering, 2018Co-Authors: Hoa Thanh Le, Io Mizushima, Yasser Nour, Peter Torben Tang, Arnold Knott, Ziwei Ouyang, Flemming JensenAbstract:We report a fabrication technology for 3D air-core inductors for small footprint and Very-High-Frequency power conversions. Our process is scalable and Highly generic for fabricating inductors with a wide range of geometries and core shapes. We demonstrate spiral, solenoid, and toroidal inductors, a toroidal transformer and inductor with advanced geometries that cannot be produced by wire winding technology. The inductors are embedded in a silicon substrate and consist of through-silicon vias and suspended windings. The inductors fabricated with 20 and 25 turns and 280-350 μm heights on 4-16 mm^2 footprints have an inductance from 34.2 to 44.6 nH and a quality factor from 10 to 13 at frequencies ranging from 30 to 72 MHz. The air-core inductors show threefold lower parasitic capacitance and up to a 140% Higher-quality factor and a 230% Higher-operation Frequency than silicon-core inductors. A 33 MHz boost converter mounted with an air-core toroidal inductor achieves an efficiency of 68.2%, which is better than converters mounted with a Si-core inductor (64.1%). Our inductors show good thermal cycling stability, and they are mechanically stable after vibration and 2-m-drop tests. A flexible and scalable technique for making microinductors with a wide range of geometries leads to better performing power systems. Microinductors are a fundamental component of electronic devices and are used in a variety of applications, including microactuators and biosensors. Their use as energy-storage elements for switched-mode power supplies (SMPS) is an emerging application, and the miniaturization of SMPS — in which all of the necessary components are integrated onto one chip — has become a focus for future power technologies. This led Hoa Thanh Le and colleagues from the Technical University of Denmark to develop a technique for fabricating 3D air-core microinductors with a range of architectures, including spiral, solenoid and toroidal geometries, for use in Very High Frequency power applications. The team's technology can also have applications in the transmitters and receivers of radio-Frequency microelectromechanical systems.
-
Self-oscillating galvanic isolated bidirectional Very High Frequency DC-DC converter
2015 IEEE Applied Power Electronics Conference and Exposition (APEC), 2015Co-Authors: Jeppe A. Pedersen, Arnold Knott, Mickey P. Madsen, Michael A. E. AndersenAbstract:This paper describes a galvanic isolated bidirectional Very High Frequency (VHF = 30 MHz - 300MHz) Class-E converter. The reason for increasing the switching Frequency is to minimize the passive components in the converter. To make the converter topology bidirectional the rectifier has to be synchronous. This increases the complexity of the gate drives, which in this paper is solved by using a self-oscillating gate drive. A bidirectional converter has been implemented and is described in this paper; the converter reaches efficiencies above 80% in forward conduction mode and 73.5% in reverse conduction mode. The designed converter operates at a switching Frequency of 35.6 MHz, which is well within the VHF range. The same converter is also implemented with PCB embedded inductors to minimize cost and the physical volume of the total converter.
-
Outphasing control of gallium nitride based Very High Frequency resonant converters
2015 IEEE 16th Workshop on Control and Modeling for Power Electronics (COMPEL), 2015Co-Authors: Mickey P. Madsen, Arnold Knott, Michael A. E. Andersen, David J PerreaultAbstract:In this paper an outphasing modulation control method suitable for line regulation of Very High Frequency resonant converters is described. The pros and cons of several control methods suitable for Very High Frequency resonant converters are described and compared to outphasing modulation. Then the modulation technique is described and the design equations given. Finally a design example is given for a converter consisting of two class E inverters with a lossless combiner and a common half bridge rectifier. It is shown how outphasing modulation can be used for line regulation while insuring equal and purely resistive loading of the inverters. Combined with a proper design of the inverters that, insures they can achieve zero voltage switching across a wide load range, and gallium nitride FETs for the switching devices, this makes it possible to achieve more than 90% efficiency across most of the input voltage range with good line regulation.
-
Evolution of Very High Frequency Power Supplies
IEEE Journal of Emerging and Selected Topics in Power Electronics, 2014Co-Authors: Arnold Knott, Mickey P. Madsen, Toke Meyer Andersen, Peter Kamby, Jeppe A. Pedersen, Milovan Kovacevic, Michael A. E. AndersenAbstract:The ongoing demand for smaller and lighter power supplies is driving the motivation to increase the switching frequencies of power converters. Drastic increases however, come along with new challenges, namely the increase of switching losses in all components. The application of power circuits used in radio Frequency transmission equipment helps to overcome those. However, those circuits were not designed to meet the same requirements as power converters. This paper summarizes the contributions in the recent years in the application of Very High Frequency (VHF) technologies in power electronics, which show the results of the recent advances and describes the remaining challenges. The presented results include a self-oscillating gate drive, air-core inductor optimizations, an offline LED driver with a power density of 8.9 W/cm 3 , and a 120-MHz, 9-W dc powered LED driver with 89% efficiency as well as a bidirectional VHF converter. The challenges to be solved before VHF converters can be used effectively in industrial products are within those three categories: 1) components; 2) circuit architectures; and 3) reliability testing.
-
Very High Frequency half bridge DC/DC converter
2014 IEEE Applied Power Electronics Conference and Exposition - APEC 2014, 2014Co-Authors: Mickey P. Madsen, Arnold Knott, Michael A. E. AndersenAbstract:This paper presents the first, off chip, class DE (resonant half bridge) converter working in the Very High Frequency (VHF) range. The benefits of using half bridge circuits both in the inverter and rectifier part of a VHF resonant dc/dc converter are analyzed and design equations for all components in the power stage are given. The circuit has been simulated to verify the accuracy of the presented equations and an efficiency of 89% has been shown. A prototype has been implemented with self-oscillating resonant gate drives driving the switches. The prototype has been used to drive an LED string and shows an efficiency of 85% at 29 MHz with 130 V input and 13.4 W output. The efficiency was above 82% in the range 110-150 V input with output power between 10.3 W and 16.5 W.
Mickey P. Madsen - One of the best experts on this subject based on the ideXlab platform.
-
Self-oscillating galvanic isolated bidirectional Very High Frequency DC-DC converter
2015 IEEE Applied Power Electronics Conference and Exposition (APEC), 2015Co-Authors: Jeppe A. Pedersen, Arnold Knott, Mickey P. Madsen, Michael A. E. AndersenAbstract:This paper describes a galvanic isolated bidirectional Very High Frequency (VHF = 30 MHz - 300MHz) Class-E converter. The reason for increasing the switching Frequency is to minimize the passive components in the converter. To make the converter topology bidirectional the rectifier has to be synchronous. This increases the complexity of the gate drives, which in this paper is solved by using a self-oscillating gate drive. A bidirectional converter has been implemented and is described in this paper; the converter reaches efficiencies above 80% in forward conduction mode and 73.5% in reverse conduction mode. The designed converter operates at a switching Frequency of 35.6 MHz, which is well within the VHF range. The same converter is also implemented with PCB embedded inductors to minimize cost and the physical volume of the total converter.
-
Outphasing control of gallium nitride based Very High Frequency resonant converters
2015 IEEE 16th Workshop on Control and Modeling for Power Electronics (COMPEL), 2015Co-Authors: Mickey P. Madsen, Arnold Knott, Michael A. E. Andersen, David J PerreaultAbstract:In this paper an outphasing modulation control method suitable for line regulation of Very High Frequency resonant converters is described. The pros and cons of several control methods suitable for Very High Frequency resonant converters are described and compared to outphasing modulation. Then the modulation technique is described and the design equations given. Finally a design example is given for a converter consisting of two class E inverters with a lossless combiner and a common half bridge rectifier. It is shown how outphasing modulation can be used for line regulation while insuring equal and purely resistive loading of the inverters. Combined with a proper design of the inverters that, insures they can achieve zero voltage switching across a wide load range, and gallium nitride FETs for the switching devices, this makes it possible to achieve more than 90% efficiency across most of the input voltage range with good line regulation.
-
Evolution of Very High Frequency Power Supplies
IEEE Journal of Emerging and Selected Topics in Power Electronics, 2014Co-Authors: Arnold Knott, Mickey P. Madsen, Toke Meyer Andersen, Peter Kamby, Jeppe A. Pedersen, Milovan Kovacevic, Michael A. E. AndersenAbstract:The ongoing demand for smaller and lighter power supplies is driving the motivation to increase the switching frequencies of power converters. Drastic increases however, come along with new challenges, namely the increase of switching losses in all components. The application of power circuits used in radio Frequency transmission equipment helps to overcome those. However, those circuits were not designed to meet the same requirements as power converters. This paper summarizes the contributions in the recent years in the application of Very High Frequency (VHF) technologies in power electronics, which show the results of the recent advances and describes the remaining challenges. The presented results include a self-oscillating gate drive, air-core inductor optimizations, an offline LED driver with a power density of 8.9 W/cm 3 , and a 120-MHz, 9-W dc powered LED driver with 89% efficiency as well as a bidirectional VHF converter. The challenges to be solved before VHF converters can be used effectively in industrial products are within those three categories: 1) components; 2) circuit architectures; and 3) reliability testing.
-
Very High Frequency half bridge DC/DC converter
2014 IEEE Applied Power Electronics Conference and Exposition - APEC 2014, 2014Co-Authors: Mickey P. Madsen, Arnold Knott, Michael A. E. AndersenAbstract:This paper presents the first, off chip, class DE (resonant half bridge) converter working in the Very High Frequency (VHF) range. The benefits of using half bridge circuits both in the inverter and rectifier part of a VHF resonant dc/dc converter are analyzed and design equations for all components in the power stage are given. The circuit has been simulated to verify the accuracy of the presented equations and an efficiency of 89% has been shown. A prototype has been implemented with self-oscillating resonant gate drives driving the switches. The prototype has been used to drive an LED string and shows an efficiency of 85% at 29 MHz with 130 V input and 13.4 W output. The efficiency was above 82% in the range 110-150 V input with output power between 10.3 W and 16.5 W.
-
Very High Frequency resonant DC/DC converters for LED lighting
2013 Twenty-Eighth Annual IEEE Applied Power Electronics Conference and Exposition (APEC), 2013Co-Authors: Mickey P. Madsen, Arnold Knott, Michael A. E. AndersenAbstract:This paper presents a Very High Frequency DC/DC converter for LED lighting. Several resonant topologies are compared and their usability discussed. At the end the resonant SEPIC converter is chosen based on the achievable power density and total bill of material. Simulations of a 51 MHz converter with 40 V input and 15 V output are made. The simulation shows possibility of achieving efficiency up to 87 % even with a HEXFET Power MOSFET. Three prototypes of the simulated converter are implemented showing good correlation with simulations. The prototypes have efficiencies up to 84 % and power densities up to 8.9 W/cm3 (146 W/in3).
