The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
F C Lee - One of the best experts on this subject based on the ideXlab platform.
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new continuous input current charge pump Power Factor correction electronic ballast
IEEE Transactions on Industry Applications, 1999Co-Authors: Jinrong Qian, F C Lee, T YamauchiAbstract:Continuous-input current charge pump Power-Factor-correction (CIC-CPPFC) electronic ballasts are proposed in this paper. The CPPFC circuit and unity Power Factor condition using the charge pump concept are derived and analyzed. The average lamp current control with switching frequency modulation was developed so that low crest Factor and constant lamp Power operation can be achieved. The developed electronic ballast has continuous input current, so that a small line input filter can be used. The proposed CIC-CPPFC electronic ballast was implemented and tested with two 45 W fluorescent lamps. It is shown that the measured line input current harmonics satisfy IEC 1000-3-2 Class C requirements.
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current source charge pump Power Factor correction electronic ballast
Power Electronics Specialists Conference, 1997Co-Authors: Jinrong Qian, F C Lee, T YamauchiAbstract:Current source charge pump Power Factor correction (CS-CPPFC) electronic ballast is presented in this paper. Unity Power Factor condition and operation principle using the charge pump concept are derived and analyzed. Based on the steady state analysis, the design considerations are discussed in detail. It is shown that the Power switch only deals with the resonant load current, which is the same as in the two-stage approach. This feature is very attractive, since the switch in the integrated single-stage Power Factor correction converter has to carry the current not only from input but also from the load. The developed current source charge pump electronic ballast can save one choke inductor, and has a potentially low cost. The current source charge pump electronic ballast was implemented and tested. It is shown that 0.992 Power Factor and 9.0% THD can be achieved for 85-watt fluorescent lamps.
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a high efficient single stage single switch high Power Factor ac dc converter with universal input
Applied Power Electronics Conference, 1997Co-Authors: Jinrong Qian, F C LeeAbstract:A single stage single switch high Power Factor correction AC/DC converter with universal input is presented in this paper. The high Power Factor can be achieved based upon the charge pump concept and Power Factor correction stage operating in the continuous current mode. The switch has no current and voltage stresses over a wide range of load variation so that a low voltage rating device can be used. The presented converter has features of high Power Factor, high efficiency, and low cost. An 80-watt prototype was implemented to show that it has 85% higher efficiency with no voltage stress from 0.5% to 100% load variation over universal line input.
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input filter design for Power Factor correction circuits
IEEE Transactions on Power Electronics, 1996Co-Authors: V Vlatkovic, D Borojevic, F C LeeAbstract:The issues involved in the design of Power Factor correction circuit input filters are significantly different from those involved in the design of input filters for DC-DC Power converters. In many cases, the EMI and Power Factor requirements are impossible to meet using the existing filtering technology. This paper proposes the use of high-order elliptic filters to achieve the required EMI attenuation and Power Factor. The new input filter technology provides a significant filter size reduction over the standard filter designs, minimizes the filter-Power converter interaction, and maintains a good converter Power Factor. New active and passive filter damping methods that guarantee optimal filter pole damping, while virtually eliminating damping resistor Power dissipation, are proposed. The filter design procedure that makes possible a simple and fast design of filters with an arbitrary number of stages is also presented.
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single stage single phase parallel Power Factor correction scheme
Power Electronics Specialists Conference, 1994Co-Authors: Yimin Jiang, F C LeeAbstract:A new scheme of the single-phase parallel Power Factor correction (PPFC), which allows major input Power to be processed only once to achieve both unity Power Factor and tight output regulation, is established in this paper. The new PPFC circuits based on this new scheme are much simpler than the previous one. Consequently, they are competitive to the conventional two-cascade-stage system concerning the efficiency and the cost. Large signal simulation and experimental results have proven the successful operation and good performances of the proposed new PPFC circuits. >
Yanfei Liu - One of the best experts on this subject based on the ideXlab platform.
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zero ripple single stage ac dc led driver with unity Power Factor
Energy Conversion Congress and Exposition, 2013Co-Authors: Peng Fang, Brian J White, Christopher Fiorentino, Yanfei LiuAbstract:The single stage LED Driver can achieve relatively high efficiency, however the low frequency ripple current is too significant if high Power Factor has been achieved. With two stages AC-DC LED Driver structure, we can achieve high Power Factor and tight current regulation at the same time. However, the drawback of the two stage structure is relatively low efficiency and high component cost. In this paper, an innovative single stage LED Driver with ripple cancellation technology has been proposed. We can achieve almost as high efficiency and low component cost as single stage LED Driver while maintaining comparable performance to the two stages LED Driver. Our experimental prototype can achieve 1.5mA Pk-Pk 120Hz ripple current, 0.99 Power Factor and 85.5% efficiency for a universal AC input, 35W (50V-0.7A) output application.
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a digital Power Factor correction pfc control strategy optimized for dsp
IEEE Transactions on Power Electronics, 2004Co-Authors: Wanfeng Zhang, Guang Feng, Yanfei LiuAbstract:A predictive algorithm for digital control Power Factor correction (PFC) is presented in this paper. Based on this algorithm, all of the duty cycles required to achieve unity Power Factor in one half line period are calculated in advance by digital signal processors (DSP). A boost converter controlled by these precalculated duty cycles can achieve sinusoidal current waveform. One main advantage is that the digital control PFC implementation based on this control strategy can operate at a high switching frequency which is not directly dependent on the processing speed of DSP. Input voltage feed-forward compensation makes the output voltage insensitive to the input voltage variation and guarantees sinusoidal input current even if the input voltage is distorted. A prototype of boost PFC controlled by a DSP evaluation board was set up to implement the proposed predictive control strategy. Both the simulation and experimental results show that the proposed predictive strategy for PFC achieves near unity Power Factor.
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a new Power Factor correction pfc control method suitable for low cost dsp
International Telecommunications Energy Conference, 2002Co-Authors: Wanfeng Zhang, Guang Feng, Yanfei LiuAbstract:One main barrier to implement digital control for Power Factor correction (PFC) is the limited switching frequency due to the limited processor speed. A new digital PFC control method is proposed to solve this problem. For convention digital methods, the duty cycle is calculated every switching period. The new digital PFC control method uses an optimization algorithm to generate all of the required duty cycles for one half line period at one time in advance, which is based on the input current and duty cycles in the previous half tine periods. Total Harmonic Distortion (THD), which is directly related to the Power Factor, is determined as the objective function. Gradient descent is used as the optimization algorithm to minimize the THD and improve the Power Factor. The proposed new digital PFC control strategy overcomes the problem of limited switching frequency due to limited DSP speed. Simulation results show that unity Power Factor is achieved using the proposed method.
G. Joos - One of the best experts on this subject based on the ideXlab platform.
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a single stage Power Factor corrected ac dc converter
IEEE Transactions on Power Electronics, 1999Co-Authors: M. Daniele, Praveen Jain, G. JoosAbstract:This paper presents a single-stage isolated converter topology designed to achieve a regulated DC output voltage having no low-frequency components and a high-input Power Factor. The topology is derived from the basic two-switch forward converter, but incorporates an additional transformer winding, inductor and a few diodes. The proposed circuit inherently forces the input current to be discontinuous and AC modulated to achieve high-input Power Factor. The converter output is operated in discontinuous mode to minimize the bulk capacitor voltage variations when the output load is varied. Analysis of the converter is presented, and performance characteristics are given. Design guidelines to select critical components of the circuit are presented. Experimental results on a 150 W 50 kHz universal input (90-265 V) 54.75 V output AC/DC converter are given which confirm the predicted performance of the proposed topology.
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A single stage Power Factor corrected AC/DC converter
Proceedings of Intelec'96 - International Telecommunications Energy Conference, 1Co-Authors: M. Daniele, Praveen Jain, G. JoosAbstract:This paper presents a single-stage isolated Power converter topology to achieve a regulated DC output voltage having no low frequency components and a high input Power Factor. The topology is derived from the basic two-switch forward Power converter, but incorporates an additional transformer winding, an inductor and a few diodes. The proposed circuit inherently forces the input current to be discontinuous and AC modulated to achieve high input Power Factor. The Power converter's output is operated in the discontinuous mode to minimize the bulk capacitor voltage variations when the output load is varied. Analysis of the Power converter is presented and performance characteristics are given. Further, design guidelines to select critical components of the circuit are presented. Finally, experimental results on a 160 W, universal input, 54 VDC output Power converter are given which confirm the high efficiency and high Power Factor features of the proposed topology.
T A Lipo - One of the best experts on this subject based on the ideXlab platform.
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high Power Factor vernier permanent magnet machines
IEEE Transactions on Industry Applications, 2014Co-Authors: T A LipoAbstract:Vernier permanent-magnet (VPM) machines are well known for high torque density but low Power Factor. This paper deals with the low Power Factor of VPM machines. The goal is not obtained by reducing the electrical loading or adjusting current advance angle but by proposing a novel vernier topology, i.e., a dual-stator spoke-array (DSSA) VPM topology. In this paper, the characteristics of the DSSA VPM topology, such as active part, auxiliary mechanical structure, and rotor anisotropy, are analyzed in detail. Performances are evaluated based on finite-element analysis, including Power Factor, torque density, and cogging torque. The results show that the DSSA VPM topology exhibits high Power Factor, viz., ~0.9, and significantly high torque capability. The verification of the mechanical structure scheme is also done in this paper. Finally, theoretical analyses are validated by the experimental results by a 44-rotor pole 24-slot DSSA VPM prototype.
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high Power Factor vernier permanent magnet machines
Energy Conversion Congress and Exposition, 2013Co-Authors: T A LipoAbstract:Vernier permanent magnet (VPM) machines are well known for high torque density but low Power Factor. This paper deals with the low Power Factor of VPM machines. The goal is not obtained by reducing the electrical loading or adjusting current advance angle but proposing a novel vernier topology-dual-stator, spoke-array (DSSA) VPM topology. In this paper, the characteristics, such as active part, auxiliary mechanical structure and rotor anisotropy, of the DSSA VPM topology are analyzed in detail. Performances, including Power Factor, torque density, and cogging torque etc., are evaluated based on finite element analysis (FEA). The analysis results show that the DSSA VPM topology exhibits high Power Factor viz.,~0.9 and significantly high torque capability. Finally, the prototype machine has been designed, built, and is under testing. The verification of the mechanical structure scheme is done in this paper, and the experimental results will be presented in the near future.
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investigation of 9 switch dual bridge matrix converter operating under low output Power Factor
IEEE Industry Applications Society Annual Meeting, 2003Co-Authors: Lixiang Wei, T A LipoAbstract:The dual-bridge matrix converter (DBMC) concept has been gaining recognition as a promising circuit alternative. Among all the DBMC topologies with reduced number of switches, the 9-switch topology shows the least number of switches and high quality waveforms. However, it has been proven that this converter can not operate safely when the output Power Factor is less than 0.866. This paper proposes a novel method to operate the 9-switch DBMC with low output Power Factor loads. In order to accomplish this task, one additional clamp circuit switch is introduced to exchange Power when the output Power Factor is lower than 0.866. With this switch, the 9-switch DBMC can continue to provide high quality input/output waveforms when the output Power Factor, is not too low. Theoretical analysis, simulation and experimental results are presented in the paper to verify its effectiveness.
M. Daniele - One of the best experts on this subject based on the ideXlab platform.
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a single stage Power Factor corrected ac dc converter
IEEE Transactions on Power Electronics, 1999Co-Authors: M. Daniele, Praveen Jain, G. JoosAbstract:This paper presents a single-stage isolated converter topology designed to achieve a regulated DC output voltage having no low-frequency components and a high-input Power Factor. The topology is derived from the basic two-switch forward converter, but incorporates an additional transformer winding, inductor and a few diodes. The proposed circuit inherently forces the input current to be discontinuous and AC modulated to achieve high-input Power Factor. The converter output is operated in discontinuous mode to minimize the bulk capacitor voltage variations when the output load is varied. Analysis of the converter is presented, and performance characteristics are given. Design guidelines to select critical components of the circuit are presented. Experimental results on a 150 W 50 kHz universal input (90-265 V) 54.75 V output AC/DC converter are given which confirm the predicted performance of the proposed topology.
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A single stage Power Factor corrected AC/DC converter
Proceedings of Intelec'96 - International Telecommunications Energy Conference, 1Co-Authors: M. Daniele, Praveen Jain, G. JoosAbstract:This paper presents a single-stage isolated Power converter topology to achieve a regulated DC output voltage having no low frequency components and a high input Power Factor. The topology is derived from the basic two-switch forward Power converter, but incorporates an additional transformer winding, an inductor and a few diodes. The proposed circuit inherently forces the input current to be discontinuous and AC modulated to achieve high input Power Factor. The Power converter's output is operated in the discontinuous mode to minimize the bulk capacitor voltage variations when the output load is varied. Analysis of the Power converter is presented and performance characteristics are given. Further, design guidelines to select critical components of the circuit are presented. Finally, experimental results on a 160 W, universal input, 54 VDC output Power converter are given which confirm the high efficiency and high Power Factor features of the proposed topology.
