The Experts below are selected from a list of 237 Experts worldwide ranked by ideXlab platform
Qiu Dong-yuan - One of the best experts on this subject based on the ideXlab platform.
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Control Techniques of Switched Capacitor DC/DC Converters
IEEE Transactions on Power Electronics, 2004Co-Authors: Qiu Dong-yuanAbstract:The Switched Capacitor DC/DC converter is a typitical inductorless converter,in which the Capacitor is applied as main energy storage device.This kind of converter is constituted of Capacitors combined with fixed amound of switches.The Capacitor charge and discharge are realized through control the switches.Deeper analysis is made based on the review of the latest achievements on the control techniques of Switched Capacitor DC/DC converters.It is also pointed out that,for the great improvement in power level and efficiency,resonant Switched Capacitor DC/DC converters deserve our newly attention.
Chi K. Tse - One of the best experts on this subject based on the ideXlab platform.
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On Energy Efficiency of Switched-Capacitor Converters
IEEE Transactions on Power Electronics, 2013Co-Authors: Chun-kit Cheung, Chi K. Tse, Siew-chong Tan, Adrian IoinoviciAbstract:The energy-efficiency issue of Switched-Capacitor converters is still a controversial topic that requires a more in-depth discussion. In this paper, we address the issue by dividing the analysis of the entire efficiency problem into two parts. In the first part, the efficiency of a Capacitor-charging RC circuit under different aspects (partial charging, full charging, at zero Capacitor voltage, at nonzero Capacitor voltage, etc.) will be conducted. The efficiency analysis of a Capacitor-discharging RC circuit with a resistor, Capacitor, and paralleled resistor-Capacitor loads will be covered. A complete evaluation of the overall efficiency is then performed in terms of both the charging and discharging efficiencies. Based on the analysis, some design rules useful for developing high-efficiency Switched-Capacitor converters is suggested. Additionally, it is shown that the belief that quasi-Switched-Capacitor converters are more lossy than Switched-Capacitor converters is a common misconception.
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On Lossless Switched-Capacitor Power Converters
IEEE Transactions on Power Electronics, 1995Co-Authors: Chi K. Tse, S. C. Wong, M. H. L. ChowAbstract:This paper addresses the design of efficient Switched-Capacitor\npower converters. The discussion starts with a review of the fundamental\nlimitation of Switched-Capacitor circuits which shows that the topology\nof such circuits and the “forced” step changes of Capacitor\nvoltages are the inherent attributes of power loss. Although the\nargument follows from a rather trivial result from basic circuit theory,\nit addresses an important issue on the maximum efficiency achievable in\na Switched-Capacitor power converter circuit. Based on the observed\ntopological constraint of Switched-Capacitor power converter circuits,\nthe simplest lossless topology for AC/DC power conversion is deduced.\nAlso discussed is a simple version of lossless topology that achieves\nisolation between the source and the load. Finally, an experimental\nAC/DC Switched-Capacitor power converter, based on the proposed idea, is\npresented which demonstrates an improved efficiency over other existing\nSwitched-Capacitor power converters. The proposed AC/DC power converter\ncontains no inductors and thus is suitable for custom IC implementation\nfor very low power applications
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The simplest lossless Switched-Capacitor AC/DC converter
Proceedings of 1994 Power Electronics Specialist Conference - PESC'94, 1Co-Authors: Chi K. Tse, S. C. Wong, M. H. L. ChowAbstract:This paper addresses the design of efficient Switched-Capacitor power converters. The discussion starts with a review of the fundamental limitation of Switched-Capacitor circuits which shows that the topology of such circuits and the "forced" step changes of Capacitor voltages are the inherent attributes of power loss. Although the argument follows from a rather trivial result from basic circuit theory, it addresses an important issue on the maximum efficiency achievable in a Switched-Capacitor converter circuit. Based on the observed topological constraint of Switched-Capacitor converter circuits, the simplest lossless topology for AC/DC conversion is deduced. Also discussed is a simple version of lossless topology that achieves isolation between the source and the load. Finally, an experimental AC/DC Switched-Capacitor converter, based on the proposed idea, is presented which demonstrates an improved efficiency over other existing Switched-Capacitor converters. The proposed AC/DC converter contains no inductors and thus is suitable for custom IC implementation for very low power applications. >
M. H. L. Chow - One of the best experts on this subject based on the ideXlab platform.
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On Lossless Switched-Capacitor Power Converters
IEEE Transactions on Power Electronics, 1995Co-Authors: Chi K. Tse, S. C. Wong, M. H. L. ChowAbstract:This paper addresses the design of efficient Switched-Capacitor\npower converters. The discussion starts with a review of the fundamental\nlimitation of Switched-Capacitor circuits which shows that the topology\nof such circuits and the “forced” step changes of Capacitor\nvoltages are the inherent attributes of power loss. Although the\nargument follows from a rather trivial result from basic circuit theory,\nit addresses an important issue on the maximum efficiency achievable in\na Switched-Capacitor power converter circuit. Based on the observed\ntopological constraint of Switched-Capacitor power converter circuits,\nthe simplest lossless topology for AC/DC power conversion is deduced.\nAlso discussed is a simple version of lossless topology that achieves\nisolation between the source and the load. Finally, an experimental\nAC/DC Switched-Capacitor power converter, based on the proposed idea, is\npresented which demonstrates an improved efficiency over other existing\nSwitched-Capacitor power converters. The proposed AC/DC power converter\ncontains no inductors and thus is suitable for custom IC implementation\nfor very low power applications
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The simplest lossless Switched-Capacitor AC/DC converter
Proceedings of 1994 Power Electronics Specialist Conference - PESC'94, 1Co-Authors: Chi K. Tse, S. C. Wong, M. H. L. ChowAbstract:This paper addresses the design of efficient Switched-Capacitor power converters. The discussion starts with a review of the fundamental limitation of Switched-Capacitor circuits which shows that the topology of such circuits and the "forced" step changes of Capacitor voltages are the inherent attributes of power loss. Although the argument follows from a rather trivial result from basic circuit theory, it addresses an important issue on the maximum efficiency achievable in a Switched-Capacitor converter circuit. Based on the observed topological constraint of Switched-Capacitor converter circuits, the simplest lossless topology for AC/DC conversion is deduced. Also discussed is a simple version of lossless topology that achieves isolation between the source and the load. Finally, an experimental AC/DC Switched-Capacitor converter, based on the proposed idea, is presented which demonstrates an improved efficiency over other existing Switched-Capacitor converters. The proposed AC/DC converter contains no inductors and thus is suitable for custom IC implementation for very low power applications. >
Adrian Ioinovici - One of the best experts on this subject based on the ideXlab platform.
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On Energy Efficiency of Switched-Capacitor Converters
IEEE Transactions on Power Electronics, 2013Co-Authors: Chun-kit Cheung, Chi K. Tse, Siew-chong Tan, Adrian IoinoviciAbstract:The energy-efficiency issue of Switched-Capacitor converters is still a controversial topic that requires a more in-depth discussion. In this paper, we address the issue by dividing the analysis of the entire efficiency problem into two parts. In the first part, the efficiency of a Capacitor-charging RC circuit under different aspects (partial charging, full charging, at zero Capacitor voltage, at nonzero Capacitor voltage, etc.) will be conducted. The efficiency analysis of a Capacitor-discharging RC circuit with a resistor, Capacitor, and paralleled resistor-Capacitor loads will be covered. A complete evaluation of the overall efficiency is then performed in terms of both the charging and discharging efficiencies. Based on the analysis, some design rules useful for developing high-efficiency Switched-Capacitor converters is suggested. Additionally, it is shown that the belief that quasi-Switched-Capacitor converters are more lossy than Switched-Capacitor converters is a common misconception.
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Switched-Capacitor converters with multiphase interleaving control
2011 IEEE Energy Conversion Congress and Exposition, 2011Co-Authors: Sitthisak Kiratipongvoot, Siew-chong Tan, Adrian IoinoviciAbstract:This paper proposes a configuration of Switched-Capacitor converters with multiphase interleaving control that can perform conventional Switched-Capacitor voltage conversions with little electromagnetic interference over a wide range of operating condition. This is achieved by having multiple units of Switched-Capacitor converter connected in parallel and a unit selection control scheme which works along the interleaving control to vary the number of converters in operation. By having the Capacitors of inactive units connected to the output and the converters operating with output interleaving operation, the output Capacitor that is typically required in Switched-Capacitor converters for maintaining a small voltage ripple is made redundant in this configuration.
R.a. Rohrer - One of the best experts on this subject based on the ideXlab platform.
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A Switched Capacitor circuit simulator: AWEswit
IEEE Journal of Solid-State Circuits, 1994Co-Authors: R.j. Trihy, R.a. RohrerAbstract:This paper describes the modeling and simulation of Switched Capacitor circuits in AWEswit. AWEswit is a mixed signal simulator for Switched Capacitor circuits. It allows for portions of the circuit to be modeled with digital blocks controlled by an event queue. The remainder of the circuit is modeled in the analog domain. The paper describes the circuit formulations employed by AWEswit, and how they are exploited in modeling the nonidealities associated with Switched Capacitor circuits. AWEswit employs asymptotic waveform evaluation (AWE) as its core simulation engine. It combines circuit formulations in the charge-voltage and current-voltage regimes. This flexibility in the circuit formulations means that if the circuit is modeled entirely with ideal switches (i.e. no resistors), then it is automatically solved in the charge-voltage regime (like SWITCAP2). However, if portions of the circuit need to be solved in the current-voltage regime, then AWEswit automatically partitions the circuit and solves the different partitions in whichever regime is appropriate, i.e., in the current-voltage regime (using AWE to evaluate circuit response) or in the charge-voltage regime. AWEswit naturally handles the bandwidth limitations associated with Switched Capacitor circuits. In addition, it models the clock feedthrough and signal-dependent charge dump that characterize MOSFET switches. The simulator is illustrated by example. >
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AWEswit: A Switched Capacitor circuit simulator
Proceedings of IEEE Custom Integrated Circuits Conference - CICC '93, 1Co-Authors: R.j. Trihy, R.a. RohrerAbstract:A Switched Capacitor circuit simulator, AWEswit, is presented. AWEswit exploits the cyclical reconfiguration of Switched Capacitor circuits through a sequence of continuous-time circuits. It employs asymptotic waveform evaluation (AWE) to estimate the response of the state variables (Capacitor voltages) in each switching phase. For accuracy, a horizontal Pade/spl acute/ sequence is employed to extract dominant pole models for the response of the state variables. In addition, a general technique for handling complications in the AWE analysis resulting from loops of voltage sources and Capacitors is presented. This technique makes AWEswit compatible with the class of Switched Capacitor simulators that operate in the charge-voltage regime. Simulation results are presented.
