Gotowe bibliografie tematyczne / Planar transformers

Gotowa bibliografia na temat „Planar transformers”

Autor: Grafiati
Data publikacji: 4 czerwca 2021
Data aktualizacji: 20 lutego 2023

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Artykuły w czasopismach na temat "Planar transformers"

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Shen, Zhan, Bingxin Xu, Chenglei Liu, Cungang Hu, Bi Liu, Zhike Xu, Long Jin i Wu Chen. "The Modeling and Simplification of a Thermal Model of a Planar Transformer Based on Internal Power Loss". Sustainability 14, nr 19 (21.09.2022): 11915. http://dx.doi.org/10.3390/su141911915.

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With the development of high-performance wide-band-gap devices and increasing converter frequency, planar transformers are widely used in high-frequency and high-power-density power conversions. Due to the skin effect and proximity effect, accurate thermal analysis and a simplified thermal model of planar transformers are needed for quick thermal verification as well as system design. This paper proposes two thermal simplification models based on the planar transformer’s thermal impedance network. The internal power loss and thermal coupling between each component are first analyzed. Then, based on thermal radiation theory, the simplified thermal model of the planar transformer is presented. It only requires the input of the total power loss of the planar transformer to calculate the temperature rise, and it does not need the power loss of each component. Finally, the simulation and experimental verification are carried out on a MHz prototype.
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Zhao, Bin, i Gang Wang. "Equivalent Circuit of a Planar Transformer Used for TWTA". Applied Mechanics and Materials 644-650 (wrzesień 2014): 3564–67. http://dx.doi.org/10.4028/www.scientific.net/amm.644-650.3564.

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In this paper, application of planar transformers in TWTA (Travelling-wave Tube Amplifier) is investigated and a method of equivalent circuit is used to study performance of planar transformers. The lumped parameters of planar transformers are extracted by FEM (Finite Element Method).
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Dezuari, O., S. E. Gilbert, E. Belloy i M. A. M. Gijs. "High inductance planar transformers". Sensors and Actuators A: Physical 81, nr 1-3 (kwiecień 2000): 355–58. http://dx.doi.org/10.1016/s0924-4247(99)00110-7.

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Morrill, M. A., V. A. Caliskan i C. Q. Lee. "High-frequency planar power transformers". IEEE Transactions on Power Electronics 7, nr 3 (lipiec 1992): 607–13. http://dx.doi.org/10.1109/63.145149.

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Makki, Loreine, Marc Anthony Mannah, Christophe Batard, Nicolas Ginot i Julien Weckbrodt. "Investigating the Shielding Effect of Pulse Transformer Operation in Isolated Gate Drivers for SiC MOSFETs". Energies 14, nr 13 (27.06.2021): 3866. http://dx.doi.org/10.3390/en14133866.

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Wide-bandgap technology evolution compels the advancement of efficient pulse-width gate-driver devices. Integrated enhanced gate-driver planar transformers are a source of electromagnetic disturbances due to inter-winding capacitances, which serve as a route to common-mode(CM) currents. This paper will simulate, via ANSYS Q3D Extractor, the unforeseen parasitic effects of a pulse planar transformer integrated in a SiC MOSFET gate-driver card. Moreover, the pulse transformer will be ameliorated by adding distinctive shielding layers aiming to suppress CM noise effects and endure high dv/dt occurrences intending to validate experimental tests. The correlation between stray capacitance and dv/dt immunity results after shielding insertion will be reported.
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Górecki, Krzysztof, Kalina Detka i Krzysztof Górski. "Compact Thermal Model of the Pulse Transformer Taking into Account Nonlinearity of Heat Transfer". Energies 13, nr 11 (1.06.2020): 2766. http://dx.doi.org/10.3390/en13112766.

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This paper presents a compact nonlinear thermal model of pulse transformers. The proposed model takes into account differentiation in values of the temperatures of a ferromagnetic core and each winding. The model is formulated in the form of an electric network realising electrothermal analogy. It consists of current sources representing power dissipated in the core and in each of the windings, capacitors representing thermal capacitances and controlled current sources modelling the influence of dissipated power on the thermal resistances in the proposed model. Both self-heating phenomena in each component of the transformer and mutual thermal couplings between each pair of these components are taken into account. A description of the elaborated model is presented, and the process to estimate the model parameters is proposed. The proposed model was verified experimentally for different transformers. Good agreement between the calculated and measured waveforms of each component temperature of the tested pulse transformers was obtained. Differences between the results of measurements and calculations did not exceed 9% for transformers with a toroidal core and 13% for planar transformers.
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Costa, Eduard Montgomery Meira. "PLANAR TRANSFORMERS EXCITED BY SQUARE WAVES". Progress In Electromagnetics Research 100 (2010): 55–68. http://dx.doi.org/10.2528/pier09110103.

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Oshiro, O., H. Tsujimoto i K. Shirae. "Structures and characteristics of planar transformers." Journal of the Magnetics Society of Japan 12, nr 2 (1988): 385–88. http://dx.doi.org/10.3379/jmsjmag.12.385.

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Oshiro, O., H. Tsujimoto i K. Shirae. "Structures and Characteristics of Planar Transformers". IEEE Translation Journal on Magnetics in Japan 4, nr 5 (maj 1989): 332–38. http://dx.doi.org/10.1109/tjmj.1989.4564431.

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GÓRSKI, Krzysztof. "Modelling thermal properties of planar transformers". PRZEGLĄD ELEKTROTECHNICZNY 1, nr 2 (5.02.2017): 208–11. http://dx.doi.org/10.15199/48.2017.02.45.

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Rozprawy doktorskie na temat "Planar transformers"

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Ambatipudi, Radhika. "High Frequency (MHz) Planar Transformers for Next Generation Switch Mode Power Supplies". Doctoral thesis, Mittuniversitetet, Avdelningen för elektronikkonstruktion, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-20270.

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Increasing the power density of power electronic converters while reducing or maintaining the same cost, offers a higher potential to meet the current trend inrelation to various power electronic applications. High power density converters can be achieved by increasing the switching frequency, due to which the bulkiest parts, such as transformer, inductors and the capacitor's size in the convertercircuit can be drastically reduced. In this regard, highly integrated planar magnetics are considered as an effective approach compared to the conventional wire wound transformers in modern switch mode power supplies (SMPS). However, as the operating frequency of the transformers increase from several hundred kHz to MHz, numerous problems arise such as skin and proximity effects due to the induced eddy currents in the windings, leakage inductance and unbalanced magnetic flux distribution. In addition to this, the core losses whichare functional dependent on frequency gets elevated as the operating frequency increases. Therefore, this thesis provides an insight towards the problems related to the high frequency magnetics and proposes a solution with regards to different aspects in relation to designing high power density, energy efficient transformers.The first part of the thesis concentrates on the investigation of high power density and highly energy efficient coreless printed circuit board (PCB) step-down transformers useful for stringent height DC-DC converter applications, where the core losses are being completely eliminated. These transformers also maintain the advantages offered by existing core based transformers such as, high coupling coefficient, sufficient input impedance, high energy efficiency and wide frequencyband width with the assistance of a resonant technique. In this regard, several coreless PCB step down transformers of different turn’s ratio for power transfer applications have been designed and evaluated. The designed multilayered coreless PCB transformers for telecom and PoE applications of 8,15 and 30W show that the volume reduction of approximately 40 - 90% is possible when compared to its existing core based counterparts while maintaining the energy efficiency of the transformers in the range of 90 - 97%. The estimation of EMI emissions from the designed transformers for the given power transfer application proves that the amount of radiated EMI from a multilayered transformer is lessthan that of the two layered transformer because of the decreased radius for thesame amount of inductance.The design guidelines for the multilayered coreless PCB step-down transformer for the given power transfer application has been proposed. The designed transformer of 10mm radius has been characterized up to the power level of 50Wand possesses a record power density of 107W/cm3 with a peak energy efficiency of 96%. In addition to this, the design guidelines of the signal transformer fordriving the high side MOSFET in double ended converter topologies have been proposed. The measured power consumption of the high side gate drive circuitvitogether with the designed signal transformer is 0.37W. Both these signal andpower transformers have been successfully implemented in a resonant converter topology in the switching frequency range of 2.4 – 2.75MHz for the maximum load power of 34.5W resulting in the peak energy efficiency of converter as 86.5%.This thesis also investigates the indirect effect of the dielectric laminate on the magnetic field intensity and current density distribution in the planar power transformers with the assistance of finite element analysis (FEA). The significanceof the high frequency dielectric laminate compared to FR-4 laminate in terms of energy efficiency of planar power transformers in MHz frequency region is also explored.The investigations were also conducted on different winding strategies such as conventional solid winding and the parallel winding strategies, which play an important role in the design and development of a high frequency transformer and suggested a better choice in the case of transformers operating in the MHz frequency region.In the second part of the thesis, a novel planar power transformer with hybrid core structure has been designed and evaluated in the MHz frequency region. The design guidelines of the energy efficient high frequency planar power transformerfor the given power transfer application have been proposed. The designed corebased planar transformer has been characterized up to the power level of 50W and possess a power density of 47W/cm3 with maximum energy efficiency of 97%. This transformer has been evaluated successfully in the resonant converter topology within the switching frequency range of 3 – 4.5MHz. The peak energy efficiency ofthe converter is reported to be 92% and the converter has been tested for the maximum power level of 45W, which is suitable for consumer applications such as laptop adapters. In addition to this, a record power density transformer has been designed with a custom made pot core and has been characterized in thefrequency range of 1 - 10MHz. The power density of this custom core transformer operating at 6.78MHz frequency is 67W/cm3 and with the peak energy efficiency of 98%.In conclusion, the research in this dissertation proposed a solution for obtaining high power density converters by designing the highly integrated, high frequency(1 - 10MHz) coreless and core based planar magnetics with energy efficiencies inthe range of 92 - 97%. This solution together with the latest semiconductor GaN/SiC switching devices provides an excellent choice to meet the requirements of the next generation ultra flat low profile switch mode power supplies (SMPS).
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Mui, Andrew K. "A 20 dBm 5-14 GHz power amplifier with integrated planar transformers in SiGe". Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/43071.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.
Includes bibliographical references (leaves 73-74).
The integration of radar systems has taken a long journey into the modern world. Advances in signal processing technology and integrated circuit technology have lead the way for smaller, more integrated radar systems. Specific to the hardware side of a radar, the RF generation and detection once done in one location in the radar is now being replaced by small sub-elements which combine RF generation and detection at the element level. This work describes a power amplifier that can be used at the element level. The design methodology for a single stage amplifier in a Silicon Germanium Bipolar process covering 5-14 GHz is discussed. Simulation results and measurement results closely match and show peak power outputs of 25 dBm and peak power-added efficiencies (PAE) of approximately 32 %.
by Andrew K. Mui.
S.M.
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Rocha, Fabio Dalla Vecchia. "Carregador de baterias bidirecional com tranformador planar". Universidade Tecnológica Federal do Paraná, 2013. http://repositorio.utfpr.edu.br/jspui/handle/1/653.

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CAPES
Este trabalho traz um estudo da aplicação do conversor Full-Bridge bidirecional como um carregador de banco de baterias em um barramento CC de fontes de energia renováveis. O problema principal destas fontes é que são sazonais e não oferecem uma continuidade de fornecimento de potência. Assim, o uso de banco de baterias, conectado a um barramento CC compartilhado com outras fontes renováveis traz contribuições na continuidade do fornecimento de energia. O conversor proposto neste trabalho visa conectar o banco de baterias ao barramento CC e ao mesmo tempo que faz a integração dos modos de carga e descarga em um único conversor. Adicionalmente, para reduzir volume, é utilizado um transformador planar que oferece alta eficiência (máximo de 99,5%) e uma reduzida relação volume/potência. O conversor foi desenvolvido para carregar um banco de baterias de 192V. No modo de descarga, ele é suado para alimentar um barramento CC de 400V com uma potência máxima de 1,34kW. Apesar do uso do conversor full-bridge não ser novidade nestes tipos de aplicação, dois fatores serviram de motivação para este trabalho: o uso do transformador planar e a tendência mundial de integração de fontes renováveis.
This work presents a study of the application of the Full-bridge bidirectional DC converter as a battery bank charger in a DC bus of renewable energy sources. The main problem is that these sources are seasonal and do not offer a continuously power supply. Thus, the use of a battery bank connected to a DC bus shared with other renewable sources brings contributions in the continuity of power supply. The converter proposed in this work aims to connect the battery bank to the DC bus at the same time it integrates the charging and discharging modes into a single converter. Additionally, to reduce the volume, it is used a planar transformer that provides high efficiency (up to 99.5%) and a reduced volume/power ratio. The converter is designed to charge a bank of batteries of 192V. At the discharge mode, it is designed to feed a 400V DC bus with maximum power of 1.34 kW. Despite the use of the full-bridge converter is not new in these types of application, two factors served as motivation for this work: the use of planar transformer and the global trend of integration of renewable sources.
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Wong, Fu Keung, i n/a. "High Frequency Transformer for Switching Mode Power Supplies". Griffith University. School of Microelectronic Engineering, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050211.110915.

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A power supply is an essential part of all electronic devices. A switching mode power supply is a light weight power solution for most modern electronic equipment. The high frequency transformer is the backbone of modern switched mode power supplies. The skin effect and proximity effects are major problems in high frequency transformer design, because of induced eddy currents. These effects can result in transformers being destroyed and losing their power transferring function at high frequencies. Therefore, eddy currents are unwanted currents in high frequency transformers. Leakage inductance and the unbalanced magnetic flux distribution are two further obstacles for the development of high frequency transformers. Winding structures of power transformers are also a critical part of transformer design and manufacture, especially for high frequency applications. A new planar transformer with a helical winding structure has been designed and can maintain the advantages of existing planar transformers and significantly reduce the eddy currents in the windings. The maximum eddy current density can be reduced to 27% of the density of the planar transformer with meander type winding structure and 33% of the density of the transformer with circular spiral winding structure at an operating frequency of 1MHz. The voltage ratio of the transformer with helical winding structure is effectively improved to 150% of the voltage ratio of the planar transformer with circular spiral coils. With the evenly distributed magnetic flux around the winding, the planar transformer with helical winding structure is excellent for high frequency switching mode power supplies in the 21st Century.
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Wong, Fu Keung. "High Frequency Transformer for Switching Mode Power Supplies". Thesis, Griffith University, 2004. http://hdl.handle.net/10072/367650.

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A power supply is an essential part of all electronic devices. A switching mode power supply is a light weight power solution for most modern electronic equipment. The high frequency transformer is the backbone of modern switched mode power supplies. The skin effect and proximity effects are major problems in high frequency transformer design, because of induced eddy currents. These effects can result in transformers being destroyed and losing their power transferring function at high frequencies. Therefore, eddy currents are unwanted currents in high frequency transformers. Leakage inductance and the unbalanced magnetic flux distribution are two further obstacles for the development of high frequency transformers. Winding structures of power transformers are also a critical part of transformer design and manufacture, especially for high frequency applications. A new planar transformer with a helical winding structure has been designed and can maintain the advantages of existing planar transformers and significantly reduce the eddy currents in the windings. The maximum eddy current density can be reduced to 27% of the density of the planar transformer with meander type winding structure and 33% of the density of the transformer with circular spiral winding structure at an operating frequency of 1MHz. The voltage ratio of the transformer with helical winding structure is effectively improved to 150% of the voltage ratio of the planar transformer with circular spiral coils. With the evenly distributed magnetic flux around the winding, the planar transformer with helical winding structure is excellent for high frequency switching mode power supplies in the 21st Century.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Microelectronic Engineering
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Kavimandan, Mandar Dilip. "Integrated Inductors". Wright State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=wright1229637343.

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Panchal, Chirag. "Investigations of High Efficiency Wireless Power Transfer Systems (WPTS) for Electric Vehicles (EVs)". Thesis, Griffith University, 2018. http://hdl.handle.net/10072/380677.

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Over the last decade, fossil fuel prices have significantly increased due to the dependency on hydrocarbon energy sources for transportation and electricity generation. In order to solve power generation issues, most governments in the world have heavily promoted the installation of roof top solar photovoltaic (PV) in domestic low voltage and commercial high voltage distribution networks. In addition, Electric Vehicles (EVs) have been introduced to substitute the hydrocarbon fuelled transportation which is required to provide high mileage and affordable prices. Currently, EVs have been charged with the utilisation of plug-in AC and DC chargers to charge their battery bank. To expand their range, EVs are required to have larger energy storage batteries, which leads to higher costs and limits their adoption in society. Furthermore, plug-in chargers require manual operation to connect to EVs, which may create health and safety issues such as electric shock and fire. Wireless Charging Systems (WCS) have the potential to minimise both these major concerns by offering frequent charge while the EV is in stationary or dynamic modes. Frequent charge to the EVs at the car park, traffic signal and on the roads brings indefinite charging options which can dramatically reduce the battery bank size. However, improvements in some of the challenging factors such as health and safety, power levels and power efficiency requires further investigation to create a user-friendliness of the WCS for EVs. This thesis deals with the investigation of concerning issues which are limiting the development of Wireless Electric Vehicle Charging Systems (WEVCS) from becoming a part of the electrified transportation system. Currently available wireless power transfer technology for the EVs has been studied including wireless transformer structures with a variety of ferrite shapes. WEVCS are associated with many health and safety issues, which have been discussed with the current developments in international standards. Two major applications; static and dynamic WEVCS, have been explained with up-to-date progress from research laboratories, universities and industries. A variety of laboratory prototypes have been developed with the help of calculation and simulation methods, and verified with experimental techniques. Firstly, High Frequency Wireless Planar Transformers (HFWPT) are used to investigate the flux leakages and other electromagnetic compatibility (EMC) problems which are associated with the wireless charging system’s efficiency. The HFWPT was designed using the bifilar winding concept on a PCB. An LLC resonant converter has been designed to improve the conversion efficiency with a maximized air gap. Assisted by a near-field scanner, the magnetic field has been analysed with and without a magnetic ferrite core at resonant frequency. The magnetic ferrite core in this arrangement is used to minimize flux leakages and to increase the magnetizing impedance. In addition, EMC computer modeling and simulation techniques are employed to investigate the magnetic flux distribution and associated EMC problems such as stray fluxes and hot spots. A finite element method (FEM) has been used to calculate the magnetic field. The effect of the planar magnetic ferrite cores on magnetic flux distribution has been investigated by using three designs. The first design has the ferrite core only at the primary side, the second draft has a planar core on the primary and secondary side, and the third design has a U-shape magnetic core for the primary and secondary side. A new proposed design is introduced to minimize flux leakages and reduce hot spots, in order to improve the flux distribution and to increase the magnetizing impedance. Poor considerations of leakage flux between the primary and secondary coils may cause complications for persons with a pacemaker or any other life supporting electronic devices. Two scenarios are investigated via computational simulation. Firstly, a simulation of a person with an electronic biomedical implant device standing beside a car during the charging process through the WCS is investigated. Secondly, a person is walking or standing over the primary coil area of the WCS when the system is not in charging mode. Both of these scenarios include an investigation of four different versions of magnetic core configurations, to examine the outer magnetic flux distribution as well as the power distribution of the WCS by using a FEM simulation. Another concerning issue is the lower power transfer efficiency of WCS for EVs in comparison to the plug-in due to the poor coupling between the transmitter and receiver charging pads. In order to solve the problem, in-wheel WCS for EVs have been introduced with a concept proven laboratory prototype, which can operate in static and dynamic applications. The coupling coefficient is dependent on the thickness of the tire rubber and the transmitter installation height underneath the road surface. A variety of scenarios have been applied to study the in-build steel belt (IBSB) tire effect on the wireless power transfer for the static and dynamic cases. FEM simulation has been performed to investigate the magnetic flux distribution and leakage fluxes due to IBSB in the vehicle’s tire. Finally, the Wireless Vehicle to Grid (W-V2G) concept has been presented to solve future instability issues on the distribution networks created by unscheduled feedback power from renewable energy sources (RES). In addition, W-V2G can provide a platform to transfer power wirelessly in both directions: grid to vehicle and vehicle to grid where the EV’s battery can be a back-up of additional energy storage to reduce the peak demand energy requirements. A 3.7 kW wireless transformer for a single phase W-V2G prototype, and a high efficiency compact filter inductor for a D-StatCom inverter in the three phase 30 kVA W-V2G have been built with the utilisation of calculation and simulation methods. Both prototypes have been constructed and validated with experimental methods. Currently, a 3.7 kW W-V2G prototype is under development, and will be finished in future with complete systems analysis and results.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Eng & Built Env
Science, Environment, Engineering and Technology
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Ickitidze, L. P., i A. N. Mironyuk. "Planar Superconducting Magnetic Flux Transformer with Micro- and Nanosized Branches". Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35455.

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The object of the study is a superconducting film magnetic flux transformer comprising two square shaped loops with the tapering active strips and a magnetosensitive film element between them. It is shown that splitting of the active strips into parallel micro- and nanosized superconducting branches and slits increases the gain factor of the transformer, i. е., the concentration of an external magnetic field on the magnetosensitive element, by a factor of more than six. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35455
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Bodegård, Andreas. "Design of a planar transformer for a series loaded resonant converter". Thesis, Uppsala universitet, Elektricitetslära, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-414921.

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This report presents a project that has been made to present the design of a planar transformer as a part of a series loaded resonant DC/DC converter in a power unit. The design is based on an existing transformer that is not planar and so the characteristics of the transformer is translated into a planar version. A multilayer printed circuit board (PCB) design was made to fit a chosen magnetic ferrite core that was chosen based on the magnetic characteristics of the old core. Calculations were made for the loss of both core and windings and the final results show that it is possible to design a planar transformer from a traditional transformer.
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Kotte, Hari Babu. "High Frequency (MHz) Resonant Converters using GaN HEMTs and Novel Planar Transformer Technology". Doctoral thesis, Mittuniversitetet, Avdelningen för elektronikkonstruktion, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-20894.

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The increased power consumption and power density demands of modern technologies have increased the technical requirements of DC/DC and AC/DC power supplies. In this regard, the primary objective of the power supply researcher/engineer is to build energy efficient, high power density converters by reducing the losses and increasing the switching frequency of converters respectively. Operating the converter circuits at higher switching frequencies reduces the size of the passive components such as transformers, inductors, and capacitors, which results in a compact size, weight, and increased power density of the converter. Therefore, the thesis work is focussed on the design, analysis and evaluation of isolated converters operating in the 1 - 5MHz frequency region with the assistance of the latest semi conductor devices, both coreless and core based planar power transformers designed in Mid Sweden University and which are suitable for consumer applications of varying power levels ranging from 1 – 60W. In high frequency converter circuits, since the MOSFET gate driver plays a prominent role, different commercially available MOSFET gate drivers were evaluated in the frequency range of 1 - 5MHz in terms of gate drive power consumption, rise/fall times and electromagnetic interference (EMI) and a suitable driver was proposed. Initially, the research was focused on the design and evaluation of a quasi resonant flyback converter using a multilayered coreless PCB step down transformer in the frequency range of 2.7 – 4MHz up to the power level of 10W. The energy efficiency of this converter is found to be 72 - 84% under zero voltage switching conditions (ZVS). In order to further improve the energy efficiency of the converter in the MHz frequency region, the new material device GaN HEMT was considered. The comparisons were made on a quasi resonant flyback DC-DC converter using both the Si and GaN technology and it was found that an energy efficiency improvement of 8 – 10% was obtained with the GaN device in the frequency range of 3.2 – 5MHz. In order to minimize the gate drive power consumption, switching losses and to increase the frequency of the converter in some applications such as laptop adapters, set top box (STB) etc., a cascode flyback converter using a low voltage GaN HEMT and a high voltage Si MOSFET was designed and evaluated using a multi-layered coreless PCB transformer in the MHz frequency region. Both the simulation and experimental results have shown that, with the assistance of the cascode flyback converter, the switching speeds of the converter can be increased with the benefit of obtaining a significant improvement in the energy efficiency as compared to that for the single switch flyback converter. In order to further maximize the utilization of the transformer, to reduce the voltage stress on MOSFETs and to obtain the maximum power density from the converter circuit, double ended topologies were considered. Due to the lack of high voltage high side gate drivers in the MHz frequency region, a gate drive circuitry utilizing the multi-layered coreless PCB signal transformer was designed and evaluated in both a half-bridge and series resonant converter (SRC). It was found that the gate drive power consumption using this transformer was around 0.66W for the frequency range of 1.5 - v 3.75 MHz. In addition, by using this gate drive circuitry, the maximum energy efficiency of the SRC using multilayered coreless PCB power transformer was found to be 86.5% with an output power of 36.5W in the switching frequency range of 2 – 3MHz. In order to further enhance the energy efficiency of the converter to more than 90%, investigations were carried out by using the multiresonant converter topology (LCC and LLC), novel hybrid core high frequency planar power transformer and the GaN HEMTs. The simulated and experimental results of the designed LCC resonant converter show that it is feasible to obtain higher energy efficiency isolated DC/DC converters in the MHz frequency region. The peak energy efficiency of the LCC converter at 3.5MHz is reported to be 92% using synchronous rectification. Different modulation techniques were implemented to regulate the converter for both line and load variations using a digital controller. In order to realize an AC/DC converter suitable for a laptop adapter application, consideration was given to the low line of the universal input voltage range due to the GaN switch limitation. The energy efficiency of the regulated converter operating in the frequency range of 2.8 – 3.5MHz is reported to be more than 90% with a load power of 45W and an output voltage of 22V dc. In order to determine an efficient power processing method on the secondary side of the converter, a comparison was made between diode rectification and synchronous rectification and optimal rectification was proposed for the converters operating in the MHz frequency range for a given power transfer application. In order to maintain high energy efficiency for a wide load range and to maintain the narrow switching frequency range for the given input voltage specifications, the LLC resonant converter has been designed and evaluated for the adapter application. From the observed results, the energy efficiency of the LLC resonant converter is maintained at a high level for a wide load range as compared to that for the LCC resonant converter. Investigations were also carried out on isolated class E resonant DC-DC converter with the assistance of GaN HEMT and a high performance planar power transformer at the switching frequency of 5MHz. The simulated energy efficiency of the converter for the output power level of 16W is obtained as 88.5% which makes it feasible to utilize the designed isolated converter for various applications that require light weight and low profile converters. In conclusion, the research in this dissertation has addressed various issues related to high frequency isolated converters and has proposed solution by designing highly energy efficient converters to meet the current industrial trends by using coreless and core based planar transformer technologies along with the assistance of GaN HEMTs. With the provided solution, in the near future, it is feasible to realize low profile, high power density DC/DC and AC/DC converters operating in MHz frequency region suitable for various applications.
High Frequency Switch Mode Power Supplies
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Książki na temat "Planar transformers"

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Banerjee, Amal. Planar Spiral Inductors, Planar Antennas and Embedded Planar Transformers. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-08778-3.

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Hobhouse, Henry. Seeds of change: Six plants that transformed mankind. London: Pan, 2002.

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Hobhouse, Henry. Seeds of change: Fire plants that transformed mankind. London: Sidgwick, 1985.

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Seeds of change: Five plants that transformed mankind. London: Papermac, 1992.

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Seeds of change: Six plants that transformed mankind. Emeryville, CA: Shoemaker & Hoard, 2006.

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Seeds of change: Five plants that transformed mankind. New York: Harper & Row, 1986.

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Hobhouse, Henry. Seeds of change: Five plants that transformed mankind. New York: Perennial Library, 1987.

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W, Roberts E. Aging of safety class 1E transformers in safety systems of nuclear power plants. Washington, DC: Division of Engineering Technology, Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory Commission, 1996.

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Kirkpatrick, J. B. A continent transformed: Human impact on the natural vegetation of Australia. Wyd. 2. Melbourne: Oxford University Press, 1999.

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Borzyh, Stanislav. Urban evolution. ru: INFRA-M Academic Publishing LLC., 2022. http://dx.doi.org/10.12737/1841828.

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The monograph is devoted to evolution, but in the form that man gave it. It is assumed that unnatural conditions of its flow were created in cities and near them, which changed the logic of its functioning, but this has become especially noticeable over the past hundred years, during which the entire planet was included in the orbit of our influence. This made it possible to unite the Earth into one whole, but at the same time it transformed the work of natural selection, turning it into an artificial one that concerns everyone and everything, without any exceptions. Accordingly, three planes of its unfolding are considered, namely: geography, the biosphere and our species, in each of which the same dynamics of its implementation can be traced. From all this, it is concluded that today there is no wild and inherent in the whole history of his version, but the one that prevails is that we, consciously and not, planted on this space object with all its inhabitants. This new version of it is proposed to be called urban revolution - by the name of the site of its unfolding and everything that is associated with it, but it is repeatedly emphasized that the essence of the process has remained the same, the scene where it is carried out has simply been transformed. It is intended for both specialists and the general public.
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Części książek na temat "Planar transformers"

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Banerjee, Amal. "Fundamental Physics of Planar Inductors, Embedded Planar Transformers, and Planar (Patch) Antennas". W Planar Spiral Inductors, Planar Antennas and Embedded Planar Transformers, 9–88. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-08778-3_2.

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Banerjee, Amal. "SPICE Based Design and Analysis of Planar Spiral Inductors and Embedded|Integrated Planar Spiral Inductor Transformers and Planar Antennas". W Planar Spiral Inductors, Planar Antennas and Embedded Planar Transformers, 89–185. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-08778-3_3.

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Banerjee, Amal. "Introduction and Problem Statement". W Planar Spiral Inductors, Planar Antennas and Embedded Planar Transformers, 1–8. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-08778-3_1.

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Xu, Dianguo, Yueshi Guan, Yijie Wang i Xiangjun Zhang. "Air-Core Planar Inductors and Transformers on PCB". W CPSS Power Electronics Series, 91–109. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-7424-5_7.

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Tepfer, D. "Agrobacterium rhizogenes-Mediated Transformation: Transformed Roots to Transformed Plants". W Gene Transfer to Plants, 45–52. Berlin, Heidelberg: Springer Berlin Heidelberg, 1995. http://dx.doi.org/10.1007/978-3-642-79247-2_6.

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Zainal Abidin, M. Firdaus, Mohd Nadzri Mamat i Mohd Fadzil Bin Ain. "Modelling of High Frequency Coreless Planar Transformer with TWR Hexagonal Winding". W Lecture Notes in Electrical Engineering, 66–71. Singapore: Springer Singapore, 2022. http://dx.doi.org/10.1007/978-981-16-8129-5_11.

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Topping, J. F., i K. Lindsey. "Molecular Characterization of Transformed Plants". W Plant Molecular Biology — A Laboratory Manual, 427–42. Berlin, Heidelberg: Springer Berlin Heidelberg, 1997. http://dx.doi.org/10.1007/978-3-642-87873-2_9.

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Schmid, Katherine M. "Dihydrosterculate in Tobacco Transformed with Bacterial Cyclopropane Fatty Acid Synthase". W Plant Lipid Metabolism, 108–10. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-015-8394-7_31.

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Mounlinier, J., i G. Hahne. "Use of Green Fluorescent Protein to Detect Transformed Shoots". W Testing for Genetic Manipulation in Plants, 19–30. Berlin, Heidelberg: Springer Berlin Heidelberg, 2002. http://dx.doi.org/10.1007/978-3-662-04904-4_2.

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Noctor, Graham, Lise Jouanin i Christine H. Foyer. "The Biosynthesis of Glutathione Explored in Transformed Plants". W Regulation of Enzymatic Systems Detoxifying Xenobiotics in Plants, 109–24. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-015-8927-7_9.

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Streszczenia konferencji na temat "Planar transformers"

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Koizumi, M. T., R. R. Teixeira, J. B. Chiocca, I. Rede i F. C. Castaldo. "Electroplated planar transformers". W 2011 Brazilian Power Electronics Conference (COBEP 2011). IEEE, 2011. http://dx.doi.org/10.1109/cobep.2011.6085246.

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Gorecki, Krzysztof, i Krzysztof Gorski. "Compact thermal model of planar transformers". W 2017 MIXDES - 24th International Conference "Mixed Design of Integrated Circuits and Systems". IEEE, 2017. http://dx.doi.org/10.23919/mixdes.2017.8005229.

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Ammouri, Aymen, Hamed Belloumi, Tarek Ben Salah i Ferid Kourda. "High-frequency investigation of planar transformers". W 2014 International Conference on Electrical Sciences and Technologies in Maghreb (CISTEM). IEEE, 2014. http://dx.doi.org/10.1109/cistem.2014.7076927.

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Gorecki, Krzysztof, i Krzysztof Gorski. "Non-linear thermal model of planar transformers". W 2017 21st European Microelectronics and Packaging Conference (EMPC) & Exhibition. IEEE, 2017. http://dx.doi.org/10.23919/empc.2017.8346913.

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Shen, Zhan, Yanfeng Shen, Bochen Liu i Huai Wang. "Thermal Coupling and Network Modeling for Planar Transformers". W 2018 IEEE Energy Conversion Congress and Exposition (ECCE). IEEE, 2018. http://dx.doi.org/10.1109/ecce.2018.8558235.

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Aime, Jeremie, Bruno Cogitore, Gerard Meunier, Edith Clavel i Yves Marechal. "Numerical methods for eddy currents modeling of planar transformers". W 2010 14th Biennial IEEE Conference on Electromagnetic Field Computation (CEFC 2010). IEEE, 2010. http://dx.doi.org/10.1109/cefc.2010.5481285.

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Loef, Christoph, Rik W. De Doncker i Bernd Ackermann. "On high frequency high voltage generators with planar transformers". W 2014 IEEE Applied Power Electronics Conference and Exposition - APEC 2014. IEEE, 2014. http://dx.doi.org/10.1109/apec.2014.6803571.

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Ropoteanu, Constantin, i Paul Svasta. "Effects of Excitation Waveform on Developing Planar Core Transformers". W 2019 IEEE 25th International Symposium for Design and Technology in Electronic Packaging (SIITME). IEEE, 2019. http://dx.doi.org/10.1109/siitme47687.2019.8990878.

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Shelkovnikov, B. N., D. B. Bondar i A. A. Glubokov. "Simulation of monolithic planar transformers on a GaAs-substrate". W 2004 14th International Crimean Conference "Microwave and Telecommunication Technology". IEEE, 2004. http://dx.doi.org/10.1109/crmico.2004.183082.

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Shen, Zhan, Yanfeng Shen i Huai Wang. "Thermal Modelling of Planar Transformers Considering Internal Power Loss Distribution". W 2019 IEEE 4th International Future Energy Electronics Conference (IFEEC). IEEE, 2019. http://dx.doi.org/10.1109/ifeec47410.2019.9015030.

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Raporty organizacyjne na temat "Planar transformers"

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Schofield, Daryl, Joshua M. Schare, Sarah Jill Glass, Alexander William Roesler, Kevin Gregory Ewsuk, George Slama i Dave Abel. Planar LTCC transformers for high voltage flyback converters. Office of Scientific and Technical Information (OSTI), czerwiec 2007. http://dx.doi.org/10.2172/945896.

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Schofield, Daryl, Joshua M. ,. Ph D. Schare, George Slama i David Abel. Planar LTCC transformers for high voltage flyback converters: Part II. Office of Scientific and Technical Information (OSTI), luty 2009. http://dx.doi.org/10.2172/947262.

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Hagwood, Charles, K. L. Stricklett i Oskars Petersons. Operating characteristics of the proposed sampling plans for testing distribution transformers. Gaithersburg, MD: National Bureau of Standards, 2004. http://dx.doi.org/10.6028/nist.tn.1456.

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Toman, G., i R. Gazdzinski. Aging Management Guideline for commercial nuclear power plants: Power and distribution transformers. Office of Scientific and Technical Information (OSTI), maj 1994. http://dx.doi.org/10.2172/10154007.

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Roberts, E. W., J. L. Edson i A. C. Udy. Aging of safety class 1E transformers in safety systems of nuclear power plants. Office of Scientific and Technical Information (OSTI), luty 1996. http://dx.doi.org/10.2172/201806.

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Clendenin, James E. A Polarized Electron RF Photoinjector Using the Plane-Wave-Transformer (PWT) Design. Office of Scientific and Technical Information (OSTI), sierpień 2001. http://dx.doi.org/10.2172/799030.

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Jander, Georg, Gad Galili i Yair Shachar-Hill. Genetic, Genomic and Biochemical Analysis of Arabidopsis Threonine Aldolase and Associated Molecular and Metabolic Networks. United States Department of Agriculture, styczeń 2010. http://dx.doi.org/10.32747/2010.7696546.bard.

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Since the amino acids threonine and isoleucine can be limiting in mammalian diet and there is interest in increasing their abundance in certain crop plants. To meet this need, a BARD proposal was written with two main research objectives: (i) investigate new avenues for manipulating threonine and isoleucine content in plants and (ii) study the role of threonine aldolase in plant metabolism. Research conducted to meet these goals included analysis of the sub-cellular localization of threonine aldolase in the plant, analysis of metabolic flux in developing embryos, over- and under-expression of Arabidopsis threonine aldolases, and transcriptional and metabolic analysis of perturbations resulting from altered threonine aldolase expression. Additionally, the broader metabolic effects of increasing lysine biosynthesis were investigated. An interesting observation that came up in the course of the project is that threonine aldolase activity affects methionine gamma-lyase in Arabidopsis. Further research showed that threonine deaminase and methionine gamma-lyase both contribute to isoleucine biosynthesis in plants. Therefore, isoleucine content can be altered by manipulating the expression of either or both of these enzymes. Additionally, both enzymes contribute to the up to 100-fold increase in isoleucine that is observed in drought-stressed Arabidopsis. Toward the end of the project it was discovered that through different projects, both groups had been able to independently up-regulate phenylalanine accumulation by different mechanisms. The Galili lab transformed Arabidopsis with a feedbackinsensitive bacterial enzyme and the Jander lab found a feedback insensitive mutation in Arabidopsis arogenate dehydratase. Exchange of the respective plant lines has allowed a comparative analysis of the different methods for increasing phenylalanine content and the creation of double mutants. The research that was conducted as part of this BARD project has led to new insights into plant amino acid metabolism. Additionally, new approaches that were found to increase the accumulation of threonine, isoleucine, and phenylalanine in plants have potential practical applications. Increased threonine and isoleucine levels can increase the nutritional value of crop plants. Elevated isoleucine accumulation may increase the osmotic stress tolerance of plants. Up-regulation of phenylalanine biosynthesis can be used to increase the production of downstream higher-value plant metabolites of biofuel feed stocks.
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Tucker, Mark L., Shimon Meir, Amnon Lers, Sonia Philosoph-Hadas i Cai-Zhong Jiang. Elucidation of signaling pathways that regulate ethylene-induced leaf and flower abscission of agriculturally important plants. United States Department of Agriculture, styczeń 2012. http://dx.doi.org/10.32747/2012.7597929.bard.

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The Problem: Abscission is a highly regulated process, occurring as a natural terminal stage of development, in which various organs are separated from the parent plant. In most plant species, the process is initiated by a decrease in active auxin in the abscission zone (AZ) and an increase in ethylene, and may be accelerated by postharvest or environmental stresses. Another potential key regulator in abscission is IDA (Inflorescence Deficient in Abscission), which was identified as an essential peptide signal for floral organ abscission in Arabidopsis. However, information is still lacking regarding the molecular mechanisms integrating all these regulators. In our previous BARD funded research we made substantial progress towards understanding these molecular events in tomato, and the study is still in progress. We established a powerful platform for analysis of genes for regulatory proteins expressed in AZ. We identified changes in gene expression for several transcription factors (TFs) directly linked to ethylene and auxin signaling and several additional regulatory proteins not so obviously linked to these hormones. Moreover, we demonstrated using a virus-induced gene silencing (VIGS) assay that several play a functional role in the onset of abscission. Based on these results we have selected 14 genes for further analysis in stably transformed tomato plants. All 14 genes were suppressed by RNA interference (RNAi) using a constitutive promoter, and 5 of them were also suppressed using an abscission-specific promoter. Transformations are currently at different stages of progress including some lines that already display an abscission phenotype. Objectives: We propose here to (1) complete the functional analysis of the stably transformed tomato plants with T2 lines and perform transcriptome analysis using custom abscission-specific microarrays; (2) conduct an indepth analysis of the role of IDA signaling in tomato leaf and flower abscission; (3) perform transcriptome and proteome analyses to extend the earlier gene expression studies to identify transcripts and proteins that are highly specific to the separation layer (i.e., target cells for cell separation) prior to the onset of abscission; (4) extend and compliment the work in tomato using a winnowed set of genes in soybean. Methodology: Next Generation Sequencing (NGS) of mRNA will be used to further increase the list of abscission-associated genes, and for preparation of a custom tomato abscission microarray to test altered gene expression in transgenic plants. Tandem mass spectrometry (LC-MS/MS) of protein extracts from leaf petiole, flower pedicel and their AZ tissues will be used to identify the proteome of the AZ before and during abscission. AZ-specific gene promoters will be used in stably transformed tomato plants to reduce non-target phenotypes. The bean pod mottle virus (BPMV) plasmid vectors will be used for VIGS analysis in soybean. Expected Contribution: Our study will provide new insights into the regulation of ethylene-induced abscission by further revealing the role of key regulators in the process. This will permit development of novel techniques for manipulating leaf and flower abscission, thereby improving the postharvest performance of agriculturally important crops.
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Aly, Radi, James H. Westwood i Carole L. Cramer. Novel Approach to Parasitic Weed Control Based on Inducible Expression of Cecropin in Transgenic Plants. United States Department of Agriculture, maj 2003. http://dx.doi.org/10.32747/2003.7586467.bard.

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Our overall goal was to engineer crop plants with enhanced resistance to Orobanche (broomrape) based on the inducible expression of sarcotoxin-like peptide (SLP). A secondary objective was to localize small proteins such as SLP in the host-parasite union in order to begin characterizing the mechanism of SLP toxicity to Orobanche. We have successfully accomplished both of these objectives and have demonstrated that transgenic tobacco plants expressing SLP under control of the HMG2 promoter show enhanced resistance to O. aegyptiaca and O. ramosa . Furthermore, we have shown that proteins much larger than the SLP move into Orobanche tubercles from the host root via either symplastic or apoplastic routes. This project was initiated with the finding that enhanced resistance to Orobanche could be conferred on tobacco, potato, and tomato by expression of SLP (Sarcotoxin IA is a 40-residue peptide produced as an antibiotic by the flesh fly, Sarcophaga peregrina ) under the control of a low-level, root-specific promoter. To improve the level of resistance, we linked the SLP gene to the promoter from HMG2, which is strongly inducible by Orobanche as it parasitizes the host. The resulting transgenic plants express SLP and show increased resistance to Orobanche. Resistance in this case is manifested by increased growth and yield of the host in the presence of the parasite as compared to non-transgenic plants, and decreased parasite growth. The mechanism of resistance appears to operate post-attachment as the parasite tubercles attached to the transgenic root plants turned necrotic and failed to develop normally. Studies examining the movement of GFP (approximately 6X the size of SLP) produced in tobacco roots showed accumulation of green fluorescence in tubercles growing on transformed plants but not in those growing on wild-type plants. This accumulation occurs regardless of whether the GFP is targeted to the cytoplasm (translocated symplastically) or the apoplastic space (translocated in xylem). Plants expressing SLP appear normal as compared to non-transgenic plants in the absence of Orobanche, so there is no obvious unintended impact on the host plant from SLP expression. This project required the creation of several gene constructs and generation of many transformed plant lines in order to address the research questions. The specific objectives of the project were to: 1. Make gene constructs fusing Orobanche-inducible promoter sequences to either the sarcotoxin-like peptide (SLP) gene or the GFP reporter gene. 2. Create transgenic plants containing gene constructs. 3. Characterize patterns of transgene expression and host-to-parasite movement of gene products in tobacco ( Nicotiana tabacum L.) and Arabidopsis thaliana (L.). 4. Characterize response of transgenic potato ( Solanum tuberosum L.) and tomato ( Lycopersicon esculentum Mill .) to Orobanche in lab, greenhouse, and field. Objectives 1 and 2 were largely accomplished during the first year during Dr. Aly's sabbatical visit to Virginia Tech. Transforming and analyzing plants with all the constructs has taken longer than expected, so efforts have concentrated on the most important constructs. Work on objective 4 has been delayed pending the final results of analysis on tobacco and Arabidopsis transgenic plants. The implications of this work are profound, because the Orobanche spp. is an extremely destructive weed that is not controlled effectively by traditional cultural or herbicidal weed control strategies. This is the first example of engineering resistance to parasitic weeds and represents a unique mode of action for selective control of these weeds. This research highlights the possibility of using this technique for resistance to other parasitic species and demonstrates the feasibility of developing other novel strategies for engineering resistance to parasitic weeds.
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Palukaitis, Peter, Amit Gal-On, Milton Zaitlin i Victor Gaba. Virus Synergy in Transgenic Plants. United States Department of Agriculture, marzec 2000. http://dx.doi.org/10.32747/2000.7573074.bard.

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Transgenic plants expressing viral genes offer novel means of engendering resistance to those viruses. However, some viruses interact synergistically with other viruses and it is now known that transgenic plants expressing particular genes of one virus may also mediate synergy with a second virus. Thus, our specific objectives were to (1) determine if transgenic plants resistant to one virus showed synergy with another virus; (2) determine what viral sequences were essential for synergy; and (3) determine whether one of more mechanisms were involved i synergy. This project would also enable an evaluation of the risks of synergism associated with the use of such transgenic plants. The conclusion deriving from this project are as follows: - There is more than one mechanism of synergy. - The CMV 2b gene is required for synergistic interactions. - Synergy between a potyvirus and CMV can break natural resistance limiting CMV movement. - Synergy operates at two levels - increase in virus accumulation and increase in pathology - independently of each other. - Various sequences of CMV can interact with the host to alter pathogenicity and affect virus accumulation. - The effect of synergy on CMV satellite RNA accumulatio varies in different systems. - The HC-Pro gene may only function in host plant species to induce synergy. - The HC-Pro is a host range determinant of potyviruses. - Transgenic plants expressing some viral sequences showed synergy with one or more viruses. Transgenic plants expressing CMV RNA 1, PVY NIb and the TMV 30K gene all showed synergy with at least one unrelated virus. - Transgenic plants expressing some viral sequences showed interference with the infection of unrelated viruses. Transgenic plants expressing the TMV 30K, 54K and 126K genes, the PVY NIb gene, or the CMV 3a gene all showed some level of interference with the accumulation (and in some cases the pathology) of unrelated viruses. From our observations, there are agricultural implications to the above conclusions. It is apparent that before they are released commercially, transgenic plants expressing viral sequences for resistance to one virus need to be evaluated fro two properties: - Synergism to unrelated viruses that infect the same plant. Most of these evaluations can be made in the greenhouse, and many can be predicted from the known literature of viruses known to interact with each other. In other cases, where transgenic plants are being generated from new plant species, the main corresponding viruses from the same known interacting genera (e.g., potexviruses and cucumoviruses, potyviruses and cucumoviruses, tobamoviruses and potexviruses, etc.) should be evaluated. - Inhibition or enhancement of other resistance genes. Although it is unlikely that plants to be released would be transformed with HC-Pro or 2b genes, there may be other viral genes that can affect the expression of plant genes encoding resistance to other pathogens. Therefore, transgenic plants expressing viral genes to engender pathogen-derived resistance should be evaluated against a spectrum of other pathogens, to determine whether those resistance activities are still present, have been lost, or have been enhanced!
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