共查询到20条相似文献,搜索用时 15 毫秒
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使用开关电源供电,设计了电力测控装置高速高精度模数转换电路,提出了抗干扰措施,讨论了电路设计和优化方案.测试结果表明,开关电源加上后置滤波以及电路精心的设计和布局、布线,可以成为为高速ADC供电的高效率解决方案. 相似文献
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Lee B.S. Jaehong Hahn Enjeti P.N. Pitel I.J. 《Industrial Electronics, IEEE Transactions on》1999,46(3):483-494
This paper proposes a robust three-phase active power-factor-correction (PFC) and harmonic reduction scheme suitable for higher power applications. The proposed system is a unique combination of a low-kilovoltampere 12-pulse rectifier system with a single-phase boost PFC scheme to shape the input current to near sinusoidal waveshape. The voltampere rating of the active PFC converter is 0.05 pu and is not exposed to line transients under varying load conditions. The proposed system is suitable for utility interface of higher power rectifiers employed in power supplies and adjustable-speed drive systems which demand clean input power characteristics in the range of 1-500 kW. The proposed system is rugged and, in the event the active control were to fail, the system reverts to 12-pulse operation with fifth and seventh harmonic cancellation. Analysis and design of the system is examined in detail, and simulation and experimental results on a 10 kVA prototype are shown 相似文献
5.
《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1973,61(8):1153-1154
The use of magnetoresistors, which are being developed in this laboratory for practical uses, such as regulation of power supplies and magnetic fields, is discussed. 相似文献
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Mathuna S.C.O. Byrne P. Duffy G. Chen W. Ludwig M. O'Donnell T. McCloskey P. Duffy M. 《Industrial Electronics, IEEE Transactions on》2004,51(6):1305-1312
This paper reviews data from the International Technology Roadmap for Semiconductors to establish where dc-dc converters are headed in the first decade of the new millennium. It focuses on the high performance computing (high current, fast response, high power density) and portable/handheld (low profile) sectors. Magnetics and power device packaging technologies needed to allow power supplies to move to operating frequencies in the 1-10 MHz region are discussed. It introduces the concept of magnetic components fully embedded (windings and core) in PCB and silicon offering low profile and low losses at high frequency. It also reviews developments in wirebond-free power packaging such as flip-chip assembly that offer low profile, reduced parasitics and increased thermal performance. Finally, consideration is given to the changes in the power electronics industry that may need to be addressed to enable these new technologies to play a strategic role. 相似文献
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This paper develops a method for simultaneously designing the power stage and controller for a switching power supply. The method utilizes a numerical optimization procedure, which facilitates computer-aided design. It is found that better performance can be achieved than with a traditional two-step design process, where the power stage and controller are designed sequentially. Optimization and simulation results for a buck power converter are presented to illustrate the design process and benefits 相似文献
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《Power Electronics, IEEE Transactions on》1997,12(6):1017-1027
Single-stage isolated power-factor-corrected power supplies (SSIPP) have the attractive features of fast regulation and a single control loop. However, SSIPP circuits also have higher voltage stress and heavier loss (when compared with a normal DC-DC power converter), which severely limit their practical applications. In this paper, the authors propose to add active clamping to SSIPP to recycle the energy trapped in the leakage inductance of their transformer (to keep the switch voltage stress low) and to achieve soft switching of their electronic devices (to further reduce the loss). This arrangement significantly improves the viability of SSIPP for practical applications. The auxiliary active-clamping transistor in the proposed circuit uses the same control/driver circuit as the main switching transistor. Simulations and experimental works verifying the operation of the converter are reported 相似文献
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Analysis of the newly discovered mixed-mode EMI noises provides a better understanding of the filter attenuation mechanism. Many practical design issues are investigated from this point of view. Hopefully, the results given in the paper reduce the mystery and the cut-and-try process in filter design in offline power supplies 相似文献
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The authors present an electrical design inspection (EDI) methodology that combines advanced power circuit simulation techniques and RISC (reduced instruction set computing) workstation hardware to use simulation in the day-to-day design of electronic power supplies. This methodology makes use of circuit simulation to detect design faults in electronic power supplies and prevent them from propagating further in the product realization process. A hierarchy of inspections which form the basis of EDI methodology, is introduced. The methodology has been embedded in a prototype electrical design inspection system which has been tested on a Sun Sparcserver 4/490 dedicated to circuit simulation. The power of this methodology has been illustrated by its application to a self-oscillating variable-frequency DC-DC power converter with peak current control. It is demonstrated that EDIS can automatically execute inspections requiring an accurate determination of the steady-state solution of the circuit, and process these results. The steady-state accelerator capability within the SIMPLIS circuit simulator has made it possible to achieve this in an unprecedentedly short CPU time 相似文献
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《Solid-State Circuits, IEEE Journal of》1980,15(5):796-799
A new bandgap current reference is described which can be used to control the injector current of I/SUP 2/L circuits for supply voltages down to about 1 V. For small currents the total injector current is obtained as a mirror of the reference current. For large injector currents the current control is performed by a series regulator which compares the injector current of one I/SUP 2/L gate to the reference current. The described reference current can be adjusted to give a variation with temperature of about 60 ppm//spl deg/C over the temperature range -10 to +70/spl deg/C. However, in some applications a nonzero, but well controlled temperature coefficient is desired. It is shown how a temperature stable ring oscillator with I/SUP 2/L gates can be constructed by tailoring the temperature dependence of the supply current appropriately. 相似文献
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《Solid-State Circuits, IEEE Journal of》1972,7(4):288-292
Silicon-controlled-rectifier (SCR) power supplies employing capacitor input filters cause large-pulse line currents. Usually the associated transformer is designed to have a minimal amount of leakage inductance. This paper studies such a system and concludes that there is an optimum value of leakage inductance that minimizes the line current and the transformer size. SCR and capacitor currents are also reduced. Design equations and curves are included. 相似文献
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Kutluay K. Cadirci Y. Ozkazanc Y.S. Cadirci I. 《Industrial Electronics, IEEE Transactions on》2005,52(5):1315-1327
This paper presents a new, online, battery state-of-charge estimation and monitoring system for both the discharge and charge periods of sealed lead-acid batteries, commonly used in telecommunication power systems as backup power supplies. The proposed monitoring system is based on discharge time versus discharge rate data given in manufacturers' data sheets, and coulometric measurements, without the need for any battery voltage measurement under open-circuit conditions. The corresponding battery management system can perform both the online monitoring and battery charging tasks by the use of the same low-cost 8-bit microcontroller. Battery state-of-charge monitoring tests have been carried out under both constant and dynamic load conditions and for alternate charge-discharge cycles of lead-acid batteries of different capacities, and for different operating temperatures. The test results have shown that a very good accuracy (better than 3%-4%) in the estimation of available capacity is obtained for various charge-discharge strategies corresponding to practical operating conditions. Changes in battery characteristics which occur due to aging are also taken into account by estimating the actual capacity of the battery and adopting the corresponding recharacterization of the aged cells automatically. 相似文献
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K. Meissner M. Steinhagen H. -J. Will 《e & i Elektrotechnik und Informationstechnik》1999,116(4):239-243
Since many years the calibration of test equipments is one of the main tasks in the technology of length measurement. Through the reduction of tolerances within the manufacturing process the request for high quality of the measuring instruments and test procedures rises. The classification of test equipments depends on the roughness and the deviation of size, form and position. During the tests we analysed plug gauges and ring gauges whose size was changed in phases. The aptitude of test procedures with 2D- or 3D-measuring instruments can be identified with the help of the developed software. 相似文献
15.
A gradual degradation has been observed in the RF performance of GaAs power FETs. Electrical and physical analyses have been carried out, indicating the role played by the surface. A plasma enhanced chemical vapour deposited silicon nitride film is established as a suitable surface passivation. 相似文献
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An optimal formulation and solution of short-range operating problems for a power system with flow constraints 总被引:1,自引:0,他引:1
The complete problem, to minimize the operating cost of a hydrothermal generation system over one day (or one week) is formulated and solved through a few assumptions: the dc approximation and a linear law for the fuel costs, primarily the methods used mix the combinatorial and the electrical features of the problem. New methods employed are a branch and bound method for the thermal unit commitment, a gradient method to set the hydropower, and an economic dispatch routine with active flow constraints. 相似文献
17.
This paper introduces and analyzes a decentralized network congestion control algorithm which has dynamic adaptations at both user ends and link ends, a so-called general primal-dual algorithm. We obtain sufficient conditions for local stability of this algorithm in a general topology network with heterogeneous round-trip delays. Then, as an implementation of this algorithm in the Internet, we introduce an AQM (Active Queue Management) scheme called Exponential-RED (E-RED), which outperforms RED and is inherently stable when combined with TCP-Reno or its variants for high-speed networks. 相似文献
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Wassim Hamidouche Clency Perrine Yannis Pousset Christian Olivier 《Journal of Visual Communication and Image Representation》2011,22(6):563-574
In this paper we propose a novel scheme for real time SVC-based video transmission over MIMO channels in the context of Joint Source Channel Coding (JSCC). This scheme compares the transmission of the H.264/SVC video over four precoder solutions, namely Max-SNR, WF, QoS and E-dmin. We exploit the high flexibility of the QoS precoder to minimize the total distortion of the received video. The proposed adaptive QoS precoder takes into account the scalability of the H.264/SVC standard jointly with the instantaneous MIMO channel statue. Finally, the proposed scheme is evaluated over both statistical and time varying realistic MIMO channels.This study provides the performance of these four precoder designs in term of BER, ML decoder complexity and the quality of the received video. We show that the precoder solutions providing the best BER performance are not usually the most appropriate for real time video transmission. However, the adaptive QoS precoder which uses three configurations, by considering both the importance of the video bitstream and the channel statue, provides the best Rate-Distortion performance regardless the channel conditions.We assess the accuracy of these four precoder solutions against channel estimation errors over time varying realistic MIMO channel. The results shows that the adaptive QoS precoder remains robust against channel estimation errors even at high mobility speed. 相似文献
19.
A technique for searching for the optimum set of modulation indices for phase-modulated residual carrier communication systems is presented. The emphasis is on simultaneous range and data operations. The technique proposed suppresses the undesired signals and allows for a specified bit error rate (BER) degradation in the data channel. At the same time, the technique provides optimum power division between the carrier, the range, and the data channel. An algorithm based on the proposed technique, along with numerical results demonstrating its applicability, is presented 相似文献
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Wilbanks M.W. Patterson G.L. IV Pohle H. Clark W.T. III 《Antennas and Propagation Magazine, IEEE》2006,48(2):42-47
Infrared camera images are used to calculate the power deposited on a target by a millimeter wave source. Thin carbon-impregnated sheets of Kapton are illuminated with RF energy, and then infrared images in the 3-5 /spl mu/m band provide temperature data that is used to numerically solve the heat equation and obtain absorbed power values. Techniques to determine the electrical properties of Kapton up to 94 GHz were developed. 相似文献