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oe1(光电查) - 科学论文

17 条数据
?? 中文(中国)
  • An efficient wide input wide output <scp>CrCM flyback</scp> converter <scp>in high</scp> a??power <scp>LED</scp> lighting

    摘要: This paper deals with a power factor corrected (PFC) flyback converter for high-power light emitting diode lighting applications. This flyback converter is designed to operate in critical conduction mode to achieve improved power quality at universal AC mains and high efficiency with the low component count. The converter is analyzed using state-space analysis with closed-loop stability under varying input and output conditions. The PFC converter is designed and implemented with wide input and wide output variations. The performance of the prototype is also investigated for improved power quality such as power factor and harmonics distortion of AC mains current at universal AC mains of 85 to 265 V. The achieved efficiency of this converter is 92% and total harmonic distortion is less than 6% over universal AC mains for a prototype of 100 W, which are much improved results as compared to discontinuous conduction mode operation of the same converter.

    关键词: state-space analysis,bode plot,power factor correction,critical conduction mode,stability,LED,power quality

    更新于2025-09-23 15:21:01

  • Three-Legs Interleaved Boost Power Factor Corrector for High-Power LED Lighting Application

    摘要: In this article, a three-leg interleaved boost Power Factor Corrector (IBPFC) converter for energy-efficient LED lighting systems connected to the main grid was discussed. This IBPFC circuit presented features 60 kHz of commutation frequency and up to 3 kW of power rating. The controlled rectifier front-end boost PFC supplied a DC/DC converter to drive power LEDs suitable for street lighting or a lighting system for a stadium, etc. The IBPFC operated in continuous current mode (CCM). The ripple impact of the IBPFC converter was analyzed and a novel methodology of inductance design was presented. In the proposed design approach, the derivative calculation of the current ripple peak compared with the derivative of the input current was used to define a critical inductance value to ensure the CCM condition. Experimental validation was provided on a 3kW prototype.

    关键词: IGBT,continuous current mode (CCM),interleaved converters,three-phase boost converter,ripple analysis,high-power LED lighting,power factor correction (PFC)

    更新于2025-09-23 15:21:01

  • [IEEE 2020 IEEE Texas Power and Energy Conference (TPEC) - College Station, TX, USA (2020.2.6-2020.2.7)] 2020 IEEE Texas Power and Energy Conference (TPEC) - A Simplified DC Capacitor Active Voltage-Balance Algorithm with Common-Mode Voltage Reduction using Active-Zero SVPWM for Three-Level Photovoltaic Grid-Tie Inverter Application

    摘要: This paper introduces a digitally controlled single-phase rectifier with power factor correction (PFC) based on a modified three-level boost converter topology. In comparison with the conventional boost-based systems, the new PFC rectifier has about three times smaller inductor and significantly lower switching losses. The improvements are achieved by replacing the output capacitor of the boost converter with a nonsymmetric active capacitive divider, with a 3:1 division ratio, and by utilizing the downstream converter stage for the capacitive divider’s center-tap voltage regulation. The nonsymmetric voltage divider and applied switching sequence effectively provide four-level converter behavior using the same number of components as three-level converters. As a result, a 66% reduction of the inductor compared to the conventional boost-based PFC and a 33% compared to the standard three-level solutions operating at the same effective switching frequencies are also achieved. Experimental results obtained with a 400 W, 200 kHz, universal input voltage (85 Vrms –265 Vrms) PFC prototype demonstrate three times smaller inductor current ripple than that of the conventional boost converter allowing for the same inductor reduction. Efficiency improvements of up to a 6% are also demonstrated.

    关键词: boost converter,power factor correction (PFC),multilevel converters,AC-DC converters

    更新于2025-09-23 15:21:01

  • A High-Power-Factor Dimmable LED Driver with Integrated Boost Converter and Half-Bridge-Topology Converter

    摘要: This paper proposes a dimmable light-emitting diode (LED) driver featuring a high power factor and zero-voltage switching on (ZVS). The circuit is obtained by integrating a boost converter and a dc-dc converter with half-bridge topology. The high power factor is achieved by operating the boost converter in discontinuous current mode (DCM). The LEDs are dimmed by the control scheme of asymmetrical pulse-width modulation (ASPWM). The developed circuit eliminates the inherited dc-o?set current of the transformer in a conventional asymmetrical half-bridge converter by introducing a balance capacitor. Both active switches can operate at ZVS by freewheeling the boost inductor current and the transformer magnetizing current to discharge the energy stored in their parasitic capacitance. The circuit operation is analyzed in detailed, and mathematical equations are derived. Finally, a 115-W prototype circuit for driving high brightness LEDs was built and tested. The experimental results verify the feasibility of the proposed LED driver with satisfactory performance. It can achieve a high power factor and ZVS operation.

    关键词: power-factor correction,half-bridge converter,zero-voltage switching on (ZVS),asymmetrical pulse-width modulation (ASPWM),light-emitting diode (LED)

    更新于2025-09-23 15:21:01

  • Design and Implementation of 150 W AC/DC LED Driver with Unity Power Factor, Low THD, and Dimming Capability

    摘要: This paper presents the implementation of a two-stage light-emitting diode (LED) driver based on commercial integrated circuits (IC). The presented LED driver circuit topology, which is designed to drive a 150 W LED module, consists of two stages: AC-DC power factor correction (PFC) stage and DC/DC power converter stage. The implementation of the PFC stage uses IC NCP1608, which uses the critical conduction mode to guarantee a unity input power factor with a wide range of input voltages. The DC/DC power converter with soft-switching characteristics for the entire load range uses IC FLS2100XS. Furthermore, the design of an electromagnetic interference (EMI) filter for the LED driver and the dimming control circuit are discussed in detail. The hardware prototype, an LED lighting system, with a rated power of 150 W/32 V from a nominal 220 V/50 Hz AC voltage supply was tested to show the effectiveness of the design. The presented LED driver was tested for street lighting, and the experimental results show that the power factor (PF) was higher than 0.97, the total harmonics distortion (THD) was lower than 7%, and the efficiency was 91.7% at full load. The results prove that the performance of the presented LED driver complies with the standards: IEC61000-3-2 and CIRSP 15:2009.

    关键词: EMI filter,power factor correction,LED driver,LLC resonant converter

    更新于2025-09-23 15:19:57

  • [IEEE 2019 IEEE 26th International Symposium on the Physical and Failure Analysis of Integrated Circuits (IPFA) - Hangzhou, China (2019.7.2-2019.7.5)] 2019 IEEE 26th International Symposium on Physical and Failure Analysis of Integrated Circuits (IPFA) - Application of Laser Deprocessing Technique in Physical Failure Analysis on Memory Bit-counting

    摘要: This paper introduces a digitally controlled single-phase rectifier with power factor correction (PFC) based on a modified three-level boost converter topology. In comparison with the conventional boost-based systems, the new PFC rectifier has about three times smaller inductor and significantly lower switching losses. The improvements are achieved by replacing the output capacitor of the boost converter with a nonsymmetric active capacitive divider, with a 3:1 division ratio, and by utilizing the downstream converter stage for the capacitive divider’s center-tap voltage regulation. The nonsymmetric voltage divider and applied switching sequence effectively provide four-level converter behavior using the same number of components as three-level converters. As a result, a 66% reduction of the inductor compared to the conventional boost-based PFC and a 33% compared to the standard three-level solutions operating at the same effective switching frequencies are also achieved. Experimental results obtained with a 400 W, 200 kHz, universal input voltage (85 Vrms –265 Vrms ) PFC prototype demonstrate three times smaller inductor current ripple than that of the conventional boost converter allowing for the same inductor reduction. Efficiency improvements of up to a 6% are also demonstrated.

    关键词: boost converter,power factor correction (PFC),multilevel converters,AC-DC converters

    更新于2025-09-23 15:19:57

  • [IEEE 2019 IEEE International Conference on Unmanned Systems (ICUS) - Beijing, China (2019.10.17-2019.10.19)] 2019 IEEE International Conference on Unmanned Systems (ICUS) - Observability Enhancement of the Target Tracking Model Based on Infrared Semi-strapdown Seeker

    摘要: A large petrochemical company installed nearly 50 000 hp of electrical submersible pumps (ESPs) at an existing midwest U.S. oil ?eld. Being equipped with adjustable-speed drives (ASDs), these ESPs introduced high levels of current harmonic dis-tortion, which resulted in 14%–19% voltage harmonic distortion at the electrical utility supply. Initially, the utility noticed the low power factor (PF) and had the oil company pay for the installation of power factor correction (PFC) capacitors on their medium-voltage supply. Once installed, the utility began to have problems with these capacitors and continued to receive complaints from other customers adjacent to the oil ?eld; thus, they enforced har-monic limits, as de?ned by IEEE Std 519, at all points of common coupling. Measurements were made with a harmonic analyzer at several locations throughout the electrical system to quantify harmonics and determine the effect the ESPs were having on the utility distribution system. Computer simulations were performed to analyze different methods of harmonic mitigation. Ultimately, passive harmonic ?lters were installed on all ESPs in phases. In addition, the PFC capacitors were permanently disconnected after determining that a power system resonance condition existed. Once all phases of the project were complete, the voltage distortion level decreased to below 5%, and PF improved to near unity without the PFC capacitors. This paper will describe the effect of harmonics on the electrical distribution system caused by ASDs, practical solutions to excessive voltage harmonic distortion, reso-nance issues with PFC capacitors, and the challenges associated with different methods of harmonic mitigation.

    关键词: resonance,Adjustable-speed drives (ASDs),electrical submersible pumps (ESPs),harmonic quantities,harmonics,capacitors,harmonic ?lters,harmonic mitigation,power factor correction (PFC),harmonic distortion

    更新于2025-09-19 17:13:59

  • A Single-Stage LED Streetlight Driver with Soft-Switching and Interleaved PFC Features

    摘要: This paper presents a single-stage driver with soft-switching and interleaved power-factor correction (PFC) features suitable for light-emitting diode (LED) energy-saving streetlight applications. The proposed LED streetlight driver integrates an interleaved buck-boost PFC converter with coupled inductors and a half-bridge LLC resonant converter into a single-stage power-conversion circuit with reduced voltage stress on the DC-linked capacitor and power switches, and it is suitable for operating at high utility-line voltages. Furthermore, coupled inductors in the interleaved buck-boost PFC converter are operated in discontinuous-conduction mode (DCM) for accomplishing PFC, and the half-bridge LLC resonant converter features zero-voltage switching (ZVS) to reduce switching losses of power switches, and zero-current switching (ZCS) to decrease conduction losses of power diodes. Operational modes and design considerations for the proposed LED streetlight driver are introduced. Finally, a 144 W (36V/4A)-rated LED prototype driver is successfully developed and implemented for supplying a streetlight module and operating with a utility-line input voltage of 220 V. High power factor, low output-voltage ripple factor, low output-current ripple factor, and high efficiency are achieved in the proposed LED streetlight driver.

    关键词: converter,soft-switching,power-factor correction (PFC),streetlight driver,LED

    更新于2025-09-19 17:13:59

  • [IEEE 2019 International Conference on Power, Energy and Innovations (ICPEI) - Pattaya, Chonburi, Thailand (2019.10.16-2019.10.18)] 2019 International Conference on Power, Energy and Innovations (ICPEI) - The control of large scale grid-tied photovoltaic rooftop systems to avoid the power factor charge

    摘要: Large scale grid-tied photovoltaic (PV) rooftop systems are encouraged to install in many commercial buildings with the aim to saving the electricity energy bills. However, the support from PV system normally reduces only real power consumption while the use of reactive power is unchanged. In consequent, the power factor at the point of common coupling (PCC) may drop below the utility’s prescribed value, causing the increase of power factor charge in the energy bill. The power factor correction by controlling reactive power supplied by PV rooftop system is presented in this work. The performances of this proposed control method are examined based on time-sweep load flow calculations on DIgSILENT PowerFactory software. The simulation results show that the reactive power compensation by PV interfaced converter, with smart control algorithm, can improve the power factor at the PCC effectively, without adding new compensation devices.

    关键词: Grid-tied inverter control,photovoltaic rooftop system,power factor charge,power factor correction,reactive power compensation

    更新于2025-09-16 10:30:52

  • Disturbances Generated by Lighting Systems with LED Lamps and the Reduction in Their Impacts

    摘要: The paper deals with electromagnetic disturbances in the form of current higher harmonics, which are generated by LED lighting elements. It presents the problems related to the formation and impact of higher harmonics in the electrical systems of commercial facilities. The results of tests and analyses of current distortions for two di?erent LED lamps are included, and these are in reference to the parameters set out in the normal applicable standards. A system was then proposed to improve the quality of energy in the mains of commercial facilities in the form of a two-stage power supply. Tests of the systems with the aforementioned LED lamps were conducted and commented upon after introduction of the two-stage power supply. The ?nal part of the paper contains a summary of the obtained test results.

    关键词: electromagnetic compatibility,total harmonic distortion (THD),LED lamp,two-stage power supply,current and voltage distortion,lighting system,power factor correction (PFC),higher harmonics

    更新于2025-09-16 10:30:52