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Period-doubling bifurcation in two-stage power factor correction converters using the method of incremental harmonic balance and Floquet theory 被引量:4
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作者 Wang Fa-Qiang Zhang Hao Ma Xi-Kui 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第2期153-162,共10页
In this paper, period-doubling bifurcation in a two-stage power factor correction converter is analyzed by using the method of incremental harmonic balance (IHB) and Floquet theory. A two-stage power factor correcti... In this paper, period-doubling bifurcation in a two-stage power factor correction converter is analyzed by using the method of incremental harmonic balance (IHB) and Floquet theory. A two-stage power factor correction converter typically employs a cascade configuration of a pre-regulator boost power factor correction converter with average current mode control to achieve a near unity power factor and a tightly regulated post-regulator DC-DC Buck converter with voltage feedback control to regulate the output voltage. Based on the assumption that the tightly regulated postregulator DC-DC Buck converter is represented as a constant power sink and some other assumptions, the simplified model of the two-stage power factor correction converter is derived and its approximate periodic solution is calculated by the method of IHB. And then, the stability of the system is investigated by using Floquet theory and the stable boundaries are presented on the selected parameter spaces. Finally, some experimental results are given to confirm the effectiveness of the theoretical analysis. 展开更多
关键词 two-stage power factor correction converter incremental harmonic balance Floquet theory period-doubling bifurcation
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Fast-scale border collision bifurcation in SEPIC power factor pre-regulators 被引量:3
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作者 刘芳 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第7期2394-2404,共11页
In this paper we report a kind of fast-scale instability occurring in the single-ended primary inductance converter (SEPIC) power factor pre-regulator, which is designed to operate in discontinuous conduction mode. ... In this paper we report a kind of fast-scale instability occurring in the single-ended primary inductance converter (SEPIC) power factor pre-regulator, which is designed to operate in discontinuous conduction mode. Main results are given by exact cycle-by-cycle computer simulations as well as theoretical analysis. It is found that the instability phenomenon manifests itself as a fast-scale bifurcation at the switching period, which implies the occurrence of border collision bifurcation, or is related to the transition of the regular operating mode of the SEPIC. According to the theoretical analysis and simulation results, the effects of parameters on system stability, and the locations of the bifurcation points are confirmed. Moreover, the effects of such an instability on power factor and switching stress are also discussed. Finally, the occurrence of the asymmetric bifurcation locations is investigated. The results show that this work provides a convenient means of predicting stability boundaries which can facilitate the selection of the practical parameters. 展开更多
关键词 fast-scale instability border collision bifurcation SEPIC power factor pre-regulator discontinuous current mode
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A novel arc welding inverter with unit power factor based on DSP control 被引量:3
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作者 陈树君 曾华 +2 位作者 杜利 殷树言 陈永刚 《China Welding》 EI CAS 2006年第1期53-56,共4页
A novel inverter power source is developed characterized with constant output current and unit power factor input. Digital signal processor ( DSP ) is used to realize power factor correction and control of back-stag... A novel inverter power source is developed characterized with constant output current and unit power factor input. Digital signal processor ( DSP ) is used to realize power factor correction and control of back-stage inverter bridge of the arc welding inverter. The fore-stage adopts double closed loop proportion and integration (PI) rectifier technique and the back- stage adopts digital pulse width modulation ( PWM) technique. Simulated waves can be obtained in Matlab/Simulink and validated by experiments. Experiments of the prototype showed that the total harmonic distortion (THD) can be controlled within 10% and the power factor is approximate to 1. 展开更多
关键词 arc welding inverter power factor correction (PFC) digital signal processor (DSP) HARMONIC
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A new high-performance AC/DC power factor correction switching converter based on one-cycle control technology and active floating-charge technology 被引量:3
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作者 高潮 《Journal of Chongqing University》 CAS 2008年第2期119-124,共6页
A new family of converters,high-performance AC/DC power factor correction(PFC) switching converters with one-cycle control technology and active floating-charge technology,was derived and experimentally verified.The t... A new family of converters,high-performance AC/DC power factor correction(PFC) switching converters with one-cycle control technology and active floating-charge technology,was derived and experimentally verified.The topology of a single-phase CCM and DCM Boost-PFC switching converter was also analyzed.Its operating prniciples and control methods were expounded.Based on these,a new type of AC/DC switching converter circuits for PFC combined with one-cycle control technology was presented herein.The proposed AC/DC switching converter significantly helps improve the converter efficiency and its power factor value. 展开更多
关键词 AC/DC converter floating charge technology active power factor correction switching converter
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Unexpected low thermal conductivity and large power factor in Dirac semimetal Cd3As2 被引量:1
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作者 张成 周通 +8 位作者 梁斯航 曹钧植 袁翔 刘彦闻 沈瑶 王奇思 赵俊 杨中芹 修发贤 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第1期378-383,共6页
Thermoelectrics has long been considered as a promising way of power generation for the next decades. So far, extensive efforts have been devoted to the search of ideal thermoelectric materials, which require both hig... Thermoelectrics has long been considered as a promising way of power generation for the next decades. So far, extensive efforts have been devoted to the search of ideal thermoelectric materials, which require both high electrical conductivity and low thermal conductivity. Recently, the emerging Dirac semimetal Cd3As2, a three-dimensional analogue of graphene, has been reported to host ultra-high mobility and good electrical conductivity as metals. Here, we report the observation of unexpected low thermal conductivity in Cd3As2, one order of magnitude lower than the conventional metals or semimetals with a similar electrical conductivity, despite the semimetal band structure and high electron mobility. The power factor also reaches a large value of 1.58 mW.m 1 .K-2 at room temperature and remains non-saturated up to 400 K. Corroborating with the first-principles calculations, we find that the thermoelectric performance can be well-modulated by the carrier concentration in a wide range. This work demonstrates the Dirac semimetal Cd3As2 as a potential candidate of thermoelectric materials. 展开更多
关键词 Dirac semimetal thermal conductivity power factor thermoelectric material
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Performance Evaluation of a Permanent Magnet Electric-Drive- Reconfigured Onboard Charger with Active Power Factor Correction 被引量:3
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作者 Feng Yu Zhihao Zhu +1 位作者 Jingfeng Mao Juping Gu 《CES Transactions on Electrical Machines and Systems》 CSCD 2019年第1期72-80,共9页
This paper presents a comprehensive charging operation for an electric-drive-reconfigured onboard charger(EDROC)with active power factor correction(APFC).The charging topology exclusively utilizes the three-phase perm... This paper presents a comprehensive charging operation for an electric-drive-reconfigured onboard charger(EDROC)with active power factor correction(APFC).The charging topology exclusively utilizes the three-phase permanent magnet synchronous motor(PMSM)propulsion system as a three-channel boost-type converter in which only a contactor and a small diode bridge are added.First,the operation scenario of the EDROC is introduced.Second,the relationship between electromagnetic torque and rotor position is investigated.Third,the current ripple cancellation of the EDROC is discussed in detail.Moreover,to implement the single-phase APFC along with charging voltage/current regulation of propulsion battery,control strategies including current balancing and synchronous/interleaving PWM strategies are incorporated.Finally,200W proof-of-concept prototype-based tests are conducted under different operation scenarios. 展开更多
关键词 Active power factor correction current balancing electric-drive-reconfigured electromagnetic torque INTERLEAVING onboard charger.
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Intelligent power factor compensation equipment of three phase low voltage loads 被引量:1
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作者 罗安 董密 +1 位作者 Richard Dzudzor 《Journal of Central South University of Technology》 2002年第1期64-69,共6页
An intelligent power factor correction scheme is presented for three phase low power factor loads. This new scheme is able to perform individual phase sensing of parameters by monitoring at all times to sense a change... An intelligent power factor correction scheme is presented for three phase low power factor loads. This new scheme is able to perform individual phase sensing of parameters by monitoring at all times to sense a change in system parameters and affects individual phase correction by applying the exact amount of reactive components needed for each phase, and can also reduce negative sequence current caused by the load to improve system balance. An optimization criterion is used for the proper calculation of reactive power steps in a power compensation installation of capacitor banks. The criterion is enabled by sampling measurements performed on the electrical plant examined within specific interval of time. 展开更多
关键词 power factor correction individual phase sensing negative sequence current system balance
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Isolated single stage high power factor AC/DC converter
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作者 王卫 贲洪奇 高国安 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第4期334-337,共4页
The problem of harmonic pollution has brought wide attention with the increase of power customers. The adoption of the technology of active power factor correction (APFC) with advanced high frequency power converter i... The problem of harmonic pollution has brought wide attention with the increase of power customers. The adoption of the technology of active power factor correction (APFC) with advanced high frequency power converter is a more efficient solution to the problem of harmonic pollution. A single stage isolated high power factor AC/DC converter, which features wide range DC output, high power factor, lower harmonic pollution in input current, and phase shift PWM full bridge circuit can achieve soft switching. The principle of the circuit topology and the reasons of voltage surges across the power switch are analyzed. Experiment results illustrate that this circuit has the advantages of high power factor and lower harmonic distortion. 展开更多
关键词 single stage power factor correction CONVERTER voltage surge
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Analytical Solution for Model-Based Dynamic Power Factor Measurement in AC Resistance Spot Welding
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作者 贡亮 刘成良 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第3期333-340,共8页
On the basis of welding transformer circuit model, a new measuring method was proposed. This method measures the peak angle of the welding current, and then calculates the dynamic power factor in each half-wave. An ar... On the basis of welding transformer circuit model, a new measuring method was proposed. This method measures the peak angle of the welding current, and then calculates the dynamic power factor in each half-wave. An artificial neural network is trained and used to generate simulation data for the analytical solution, i.e. a high-order binary polynomial, which can be easily adopted to calculate the power factor online. The tailored sensing and computing system ensures that the method possesses a real-time computational capacity and satisfying accuracy. A DSP-based resistance spot welding monitoring system was developed to perform ANN computation. The experimental results suggest that this measuring method is feasible. 展开更多
关键词 dynamic power factor resistance spot welding model-based measurement ANN surface fitting Ro-gowski loop
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Frequency control system based on power factor control of asynchronous motor
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作者 孟庆春 杨飞霞 任志玲 《Journal of Coal Science & Engineering(China)》 2005年第2期86-89,共4页
Deduced the relationship between the power factor (PF) and the angular fre-quency according to the simplified equivalent circuit of asynchronous motor, forming a power factor auto-control system. An anti-interference ... Deduced the relationship between the power factor (PF) and the angular fre-quency according to the simplified equivalent circuit of asynchronous motor, forming a power factor auto-control system. An anti-interference circuit was also introduced in the middle voltage link of inverter to avoid the shift of the optimum PF point caused by the change of the load and the reliable run of the control system was assured. The experi-ment results show that it has a good self-adaptation in the whole scope of speed ad-justment and an obvious economization on energy while it runs under load. 展开更多
关键词 asynchronous motor power factor(PF) auto-control economization on energy
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Single-stage active clamp power factor correction AC/DC converter
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作者 张继红 王伟哲 +1 位作者 吴长顺 吕志伟 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第6期833-836,共4页
A simple single-stage AC/DC converter circuit with active clamp is presented. The operation theory and state are analyzed. The experimental results show that the voltage across main switch can be clamped to a certain ... A simple single-stage AC/DC converter circuit with active clamp is presented. The operation theory and state are analyzed. The experimental results show that the voltage across main switch can be clamped to a certain value,and zero voltage switching (ZVS) can be achieved. The voltage stress and switching loss are both decreased. In range of the whole load,power factors can be always more than 97%,and the highest efficiency can reach 88%. 展开更多
关键词 single stage AC/DC converter active clamp power factor correction
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A RESEARCH TO HIGH-PERFORMANCE MULTI-LEVEL SINGLE-PHASE AC/DC POWER FACTOR CORRECT SWITCHING CONVERTER
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作者 Gao Chao 《Journal of Electronics(China)》 2008年第5期716-720,共5页
This letter studies and analyzes the working features of main circuit of tri-level boost Power Factor Correct(PFC) converter and the advantages of tri-level switch converter in aspects of bearing high-voltage of power... This letter studies and analyzes the working features of main circuit of tri-level boost Power Factor Correct(PFC) converter and the advantages of tri-level switch converter in aspects of bearing high-voltage of power components,overall system loss and magnetic component selection based upon the single-level boost PFC switch converter.Besides,relying on the application of mi-croprocessor in power converter technology and DSP(Digital Signal Processing) chip's strong cal-culating capacity,the letter presents the adoption of modified scheme of tri-level boost PFC converter under the control of predictive control algorithm.Moreover,the operating principle and control method are specified,the results of circuit test and analysis are provided and the advantages of pre-dictive control technology-based multi-level boost PFC converter is verified. 展开更多
关键词 MULTI-LEVEL power factor Correct (PFC) Digital Signal Processing (DSP) Converter Predictive control MICROPROCESSOR
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Economic Improvement of Power Factor Correction: A Case Study
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作者 Kassem Wahab Mohamad Rahal Roger Achkar 《Journal of Power and Energy Engineering》 2021年第6期1-11,共11页
Power factor (PF) is simply an expression of energy efficiency, which is always expressed in terms of percentage. Technically, PF is a ratio of real power in Kilowatts to the apparent power, which is always expressed ... Power factor (PF) is simply an expression of energy efficiency, which is always expressed in terms of percentage. Technically, PF is a ratio of real power in Kilowatts to the apparent power, which is always expressed in kilovolts amperes. In AC power analysis, power is always expressed in three ways, the real power (<i></span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"></i>), reactive power (<i></span><i><span style="font-family:Verdana;">Q</span></i><span style="font-family:Verdana;"></i>), and the apparent power (<i></span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"></i>). The real power is the work useful power, while the reactive power is the wasted power in the 3-phase AC system, and the apparent power is the vectorial sum of the two powers. The increase of reactive power will reduce the presence of real power, thus making the power to be more expensive. In this paper, we will analyze the importance of improving the power factor by applying a bank of capacitors to a case study in Lebanon. Analysis of the economic improvement in the application of power factor correction is carried out. The result shows a reduction of 12 percent in the total cost. 展开更多
关键词 power factor Reactive power kVAR INDUCTIVE Apparent power Active power
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Design and Construction of A Single-Phase Power Factor Meter
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作者 A.A.Mukaila I.Olugbemi E.E.Sule 《Electrical Science & Engineering》 2020年第2期11-14,共4页
It is known that the power consumption and efficiency of an equipment owes directly to its power factor.The lower the power factor of the equipment the more the energy consumption of such equipment and vice-versa.Henc... It is known that the power consumption and efficiency of an equipment owes directly to its power factor.The lower the power factor of the equipment the more the energy consumption of such equipment and vice-versa.Hence,the need to develop an equipment to measure accurately the operating power factor of domestic and industrial equipment and appliances[1].The operating principle of this power factor meter design is based on Zero Crossing detection principle,the principle is utilized using Arduino Nano,instrument transformers,LM324 operational amplifier,generic resistor,generic XOR Gate 7488 and 2X16LCD.The input current and voltage signal is taken by the transformers and sent to the op-amp which carries out the zero crossing detection in order to get the time difference after which the microcontroller does the calculation to determine the power factor and the deficit reactive power which is then displayed on an interface[2]. 展开更多
关键词 Arduino nano Zero crossing power factor Inductive load Capacitive load
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Effect of Load Power Factor on Electromechanical Wave Propagation in Ring Power System
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作者 MOHAMMED Heikal 《Computer Aided Drafting,Design and Manufacturing》 2008年第2期109-112,共4页
One-dimensional ring power system is discredited to a number of nodes each containing a generator with internal reactance and load branch of resistance and reactance with a certain power factor. When a disturbance occ... One-dimensional ring power system is discredited to a number of nodes each containing a generator with internal reactance and load branch of resistance and reactance with a certain power factor. When a disturbance occurs at any machine in the power system, simulative analysis is performed to verify how the variation of load power factor affecting the behavior of electromechanical wave propagation by using the MATLAB package, from which different situations are presented and discussed. These results show the type of load has no effect on the behavior of electromechanical wave propagation. 展开更多
关键词 electromechanical wave propagation one-dimensional power system continuum system load power factor MATLAB
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Power Factor Improvement of AC-DC Converter Based on Separately Excited DC Motor Using Passive Filter
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作者 Shazia Baloch Mukhtiar Ahmed Mahar +1 位作者 Raza Haider Shakeel Ahmed 《Open Journal of Energy Efficiency》 2016年第3期71-77,共8页
In industries DC motor drives are very essential due to their high performance applications such as its reliability, ease of control, low cost and simplicity. And speed control of these motors is very easy due to powe... In industries DC motor drives are very essential due to their high performance applications such as its reliability, ease of control, low cost and simplicity. And speed control of these motors is very easy due to power electronic AC-DC converters. These power electronic converters are with prominent low power factor and higher Total Harmonic Distortion (THD). These converters operate only for short time resulting non-sinusoidal waveform. This problem of harmonic distortion can be mitigated by reshaping the non-sinusoidal waveform to pure sine wave. Different wave shaping techniques have been developed by using different filters among which one is tuned passive filter. This paper proposed power factor improvement and harmonic mitigation of AC-DC converters based on separately excited DC motor using tuned passive filter. In this context experimental model is designed and results are analyzed by power quality analyzer. 展开更多
关键词 DC Motors AC-DC Converters power factor Total Harmonic Distortion Passive Filters
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Accurate Reactive Power Controller and Power Factor Correction Using Fuzzy Logic
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作者 Muhammad M.A.S. Mahmoud 《Journal of Energy and Power Engineering》 2013年第6期1163-1171,共9页
This paper presents the use of fuzzy logic technique to control the reactive power of load and hence improve the source power factor. A shunt compensator is proposed, which consists of a voltage controlled reactor by ... This paper presents the use of fuzzy logic technique to control the reactive power of load and hence improve the source power factor. A shunt compensator is proposed, which consists of a voltage controlled reactor by full-wave thyristor bridge in parallel with a capacitor. The proposed voltage control technique composed of two independent fuzzy controllers, primary and secondary. The PFC (primary fuzzy controller) is designed based on linearization method to introduce to the network the nearest value of reactive power (VAR) required to correct the power factor. The SFC (secondary fuzzy controller) is designed to achieve accurate compensation for the required VAR to achieve the pre-set power factor value. Simulations for 15 different practical study cases are presented to evaluate the performance of the controller, and the results show how the designed controller is fast and accurate. Harmonics analyses are carried out up to the 13th harmonic to determine the requirement of harmonics filter. 展开更多
关键词 power systems reactive power power factor fuzzy logic control.
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New DCM Operated Single Phase Bridgeless Cuk Derived Converters for Power Factor Correction
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作者 P. M. Dhanasekaran Parasunath Veena Rajaiah Jeyabharath 《Circuits and Systems》 2016年第9期2176-2188,共13页
This paper presents a power factor corrected (PFC) new bridgeless (BL) Cuk Topologies for low power applications. A BL configuration of Cuk converter is proposed which eliminates the usage of diode bridge rectifier at... This paper presents a power factor corrected (PFC) new bridgeless (BL) Cuk Topologies for low power applications. A BL configuration of Cuk converter is proposed which eliminates the usage of diode bridge rectifier at the front end of the PFC converter, thus reducing the switching and conduction losses coupled with it. This new BL Cuk converter has two semiconductors switches. The current flow during each switching cycle interval of the converter reduces the conduction losses compared to the conventional Cuk PFC converter. It also reduces the input current ripple and Electromagnetic Interference (EMI). The inrush current during the starting period is limited and the input, output currents of the converter are continuous with minimum current ripple. Hence it is preferred mostly compared to other PFC circuits. The proposed topology works in the Discontinuous Conduction Mode (DCM) with simple control circuitry to achieve almost a unity power factor with less distortion in the input AC current. The switching of the power switches is done under zero current. The proposed PFC topologies are theoretically investigated and performance comparisons are made with the conventional rectifiers. The proposed PFC converter is simulated in MATLAB/SIMULINK with Fuzzy Logic Controller (FLC) and results are demonstrated to evaluate the effectiveness of the controller. 展开更多
关键词 Bridgeless (BL) Cuk Converter Topology power factor Correction (PFC) Total Harmonic Distortion (THD) Fuzzy Logic Controller (FLC)
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Fault Diagnosis and Phase Disposition Reconfiguration of a 5-Level Double-Boost Power Factor Corrector with Fault-Tolerant Capability
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作者 Thi Thuy Linh Pham Frederic Richardeau Guillaume Gateau 《Journal of Energy and Power Engineering》 2012年第3期418-424,共7页
A 5-level PFC (power factor correction) topology with fault-diagnostic and fault-tolerant capability is proposed and compared to known structures. It is derived from a 3-level non differential double-boost PFC inclu... A 5-level PFC (power factor correction) topology with fault-diagnostic and fault-tolerant capability is proposed and compared to known structures. It is derived from a 3-level non differential double-boost PFC including fly-cap cells. The series-connection of the two low-voltage switching-cells is decoupled by a single flying capacitor that provides a direct fault-tolerant capability and a post-failure operation increasing the availability of converter. The monitoring of the voltages across flying capacitors allows a rapid detection and localization either for open circuit failure or short-circuits failure. A PWM (pulse width modulation) phase-disposition type reconfiguration is also used and presented in order to optimize both normal operation and post-fault continuation. The design and the most important features are highlighted thanks to a digital control frame and a mock-up rated to: AC voltage network 115 V-load 400 V-nominal power 4 kW-switching frequency 62 kHz. 展开更多
关键词 PFC power factor correction) multilevel converter fault tolerant capability diagnosis.
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A New Zero-Voltage Transition Power Factor Corrected Single-Phase Single-Stage AC-to-DC Converter
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作者 Azizur Rahman 《Journal of Energy and Power Engineering》 2012年第3期397-403,共7页
This paper presents a new ZVT (zero-voltage transition) single-stage ac-to-dc converter using PWM (pulse width modulation) and HF (high frequency) transformer isolation with capacitive output filter. In this con... This paper presents a new ZVT (zero-voltage transition) single-stage ac-to-dc converter using PWM (pulse width modulation) and HF (high frequency) transformer isolation with capacitive output filter. In this converter a front-end power factor corrected boost stage integrates with a cascaded dc-to-dc bridge HF converter. The front-end boost converter operates in discontinuous current mode and ensures natural power factor correction with very simple control. The auxiliary circuit of this topology deals with very small power and is placed out of the main power path. As a result, the auxiliary circuit components have smaller power rating as opposed to main converter components. Also, output rectifier voltage is clamped to output voltage due to capacitive output filter. Identification and analyses of different operating modes of this converter are presented. Based on these analyses design example of a 50 kHz, 48 V, 1 kW ac-to-dc converter is presented. PSPICE simulation results of the designed converter are presented and explained to verify the performance of this converter. 展开更多
关键词 power factor correction high frequency isolation zero-voltage transition.
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