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Power factor

About: Power factor is a research topic. Over the lifetime, 60530 publications have been published within this topic receiving 768235 citations. The topic is also known as: electric power factor.


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Journal ArticleDOI
TL;DR: In this paper, a generalized theory of instantaneous reactive power for three-phase power systems is proposed, which is valid for sinusoidal or nonsinusoidal, balanced or unbalanced, three phase power systems with or without zero-sequence currents and/or voltages.
Abstract: A generalized theory of instantaneous reactive power for three-phase power systems is proposed in this paper. This theory gives a generalized definition of instantaneous reactive power, which is valid for sinusoidal or nonsinusoidal, balanced or unbalanced, three-phase power systems with or without zero-sequence currents and/or voltages. The properties and physical meanings of the newly defined instantaneous reactive power are discussed in detail. A three-phase harmonic distorted power system with zero-sequence components is then used as an example to show reactive power measurement and compensation using the proposed theory.

755 citations

Book
01 Jan 1986
TL;DR: In this article, the authors present a model of a single machine-infinite bus (SIB) with three-phase transformer connections for the purpose of detecting faults in a generator.
Abstract: 1. Background. Introduction. Electric Energy. Fossil-Fuel Plant. Nuclear Power Plant. Hydroelectric Power Plant. Other Energy Sources. Transmission and Distribution Systems. The Deregulated Electric Power Industry. 2. Basic Principles. Introduction. Phasor Representation. Complex Power Supplied to a One-Port. Conservation of Complex Power. Balanced Three-Phase. Per Phase Analysis. Balanced Three-Phase Power. Summary. 3. Transmission-Line Parameters. Introduction. Review of Magnetics. Flux Linkages of Infinite Straight Wire. Flux Linkages Many-Conductor Case. Conductor Bundling. Transposition. Impedance of Three Phase lines Including Ground Return. Review of Electric Fields. Line Capacitance. Determination of Line Parameters Using Tables. Typical Parameter Values. Summary. 4. Transmission-Line Modeling. Introduction. Derivation of Terminal V, I Relations. Waves on Transmission Lines. Transmission Matrix. Lumped-Circuit Equivalent. Simplified Models. Complex Power Transmission (Short Line). Complex Power Transmission (Radial Line). Complex Power Transmission (Long or Medium Lines). Power-Handling Capability of Lines. Summary. 5. Transformer Modeling and the Per Unit System. Introduction. Single-Phase Transformer Model. Three-Phase Transformer Connections. Per Phase Analysis. Normal Systems. Per Unit Normalization. Per Unit Three-Phase Quantities. Change of Base. Per Unit Analysis of Normal System. Regulating Transformers for Voltage and Phase Angle Control. Autotransformers. Transmission Line and Transformers. Summary 6. Generator Modeling I (Machine Viewpoint). Introduction. Classical Machine Description. Voltage Generation. Open-Circuit Voltage. Armature Reaction. Terminal Voltage. Power Delivered by Generator. Synchronizing Generator to an Infinite Bus. Synchronous Condensor. Role of Synchronous Machine Excitation in Controlling Reactive Power. Summary. 7. Generator Modeling II (Circuit Viewpoint). Introduction. Energy Conversion. Application to Synchronous Machine. The Park Transformation. Park's Voltage Equation. Park's Mechanical Equation. Circuit Model. Instantaneous Power Output. Applications. Synchronous Operation. Steady-State Model. Simplified Dynamic Model. Generator Connected to Infinite Bus (Linear Model). Summary 8. Generator Voltage Control. Introduction. Exciter System Block Diagram. Generator Models. Stability of Excitation System. Voltage Regulation. Generator Connected to Infinite Bus. Summary. 9. Network Matrices. Introduction. Bus Admittance Matrix. Network Solution. Network Reduction (Kron Reduction). YBUS Structure and Manipulation. Bus Impedance Matrix. Inverse Elements to Determine Columns of ZBUS. Summary. 10. Power Flow Analysis. Introduction. Power Flow Equations. The Power Flow Problem. Solution by Gauss Iteration. More General Iteration Scheme. Newton-Raphson Iteration. Application to Power Flow Equations. Decoupled Power Flow. Control Implications. Regulating Transformers in Power Flow Analysis, Power Flow Solutions for Large Power Systems. Summary. 11. Automatic Generation Control and the New Market Environment. Introduction. Power Control System Modeling. Application to Single Machine-Infinite Bus System. Simplified Analysis of Power Control System. Power Control, Multigenerator Case. Special Case Two Generating Units. Division of Power System Into Control Areas. Formulation of the Economic Dispatch Problem. Classical Economic Dispatch (Line Losses Neglected). Generator Limits Included. Line Losses Considered. Calculation of Penalty Factors. Economic Issues and Mechanisms in the New Market Environment. Transmission Issues and Effects in the New Market Environment. Summary. 12. Unbalanced System Operation. Introduction. Symmetrical Components. Use of Symmetrical Components for Fault Analysis. Sequence Network Connections for Different Types of Faults. More General Fault Circuit Analysis. Power From Sequence Variables. Sequence Representation of Y and ...D Connected Circuits. Generator Models for Sequence Networks. Transformer Models for Sequence Networks. Sequence Representation of Transmission Lines. Assembly of Sequence Networks. Fault Analysis for Realistic Power System Model. Matrix Methods. Summary. 13. System Protection. Introduction. Protection of Radial Systems. System with Two Sources. Impedance (Distance) Relays. Modified-Impedance Relays. Differential Protection of Generators. Differential Protection of Transformers. Differential Protection of Buses and Lines. Overlapping Zones of Protection. Sequence Filters. Computer Relaying. Summary. 14. Power System Stability. Introduction. Model. Energy Balance. Linearization of Swing Equation. Solution of Nonlinear Swing Equation. Other Applications. Extension to Two-Machine Case. Multimachine Application. Multimachine Stability Studies. Summary. Appendices. Reluctance. Force Generation in a Solenoid. Method of Lagrange Multipliers. Root-Locus Method. Negative- and Zero-Sequence Impedances of Synchronous Machines. Inversion Formula. Modification of Impedance Matrices. Conductor Characteristics. Selected Bibliography. Index.

749 citations

Journal ArticleDOI
TL;DR: In this paper, a systematic review of bridgeless power factor correction (PFC) boost rectifiers, also called dual-boost PFC rectifiers is presented, where loss analysis and experimental efficiency evaluation for both CCM and DCM/CCM boundary operations are provided.
Abstract: In this paper, a systematic review of bridgeless power factor correction (PFC) boost rectifiers, also called dual boost PFC rectifiers, is presented. Performance comparison between the conventional PFC boost rectifier and a representative member of the bridgeless PFC boost rectifier family is performed. Loss analysis and experimental efficiency evaluation for both CCM and DCM/CCM boundary operations are provided.

739 citations

Book
01 Jan 2008
TL;DR: In this paper, the authors present a classification of power supplies in DC-DC Converters, including voltage, current, voltage, energy, and power, and discuss the relationship among them.
Abstract: Preface. About the Author. List of Symbols. 1 Introduction. 1.1 Classification of Power Supplies. 1.2 Basic Functions of Voltage Regulators. 1.3 Power Relationships in DC-DC Converters. 1.4 DC Transfer Functions of DC-DC Converters. 1.5 Static Characteristics of DC Voltage Regulators. 1.6 Dynamic Characteristics of DC Voltage Regulators. 1.7 Linear Voltage Regulators. 1.8 Topologies of PWM DC-DC Converters 1.9 Relationships among Current, Voltage, Energy, and Power. 1.10 Electromagnetic Compatibility. 1.11 Summary. 1.12 References. 1.13 Review Questions. 1.14 Problems. 2 BuckPWMDC-DCConverter. 2.1 Introduction. 2.2 DC Analysis of PWM Buck Converter for CCM. 2.3 DC Analysis of PWM Buck Converter for DCM. 2.4 Buck Converter with Input Filter. 2.5 Buck Converter with Synchronous Rectifier. 2.6 Buck Converter with Positive Common Rail. 2.7 Tapped-Inductor Buck Converters. 2.8 Multiphase Buck Converter. 2.9 Summary. 2.10 References. 2.11 Review Questions. 2.12 Problems. 3 Boost PWM DC-DC Converter. 3.1 Introduction. 3.2 DC Analysis of PWM Boost Converter for CCM. 3.3 DC Analysis of PWM Boost Converter for DCM. 3.4 Bidirectional Buck and Boost Converters. 3.5 Tapped-Inductor Boost Converters. 3.6 Duality. 3.7 Power Factor Correction. 3.8 Summary. 3.9 References. 3.10 Review Questions. 3.11 Problems. 4 Buck-Boost PWM DC-DC Converter. 4.1 Introduction. 4.2 DC Analysis of PWM Buck-Boost Converter for CCM. 4.3 DC Analysis of PWM Buck-Boost Converter for DCM. 4.4 Bidirectional Buck-Boost Converter. 4.5 Synthesis of Buck-Boost Converter. 4.6 Synthesis of Boost-Buck (Cuk) Converter. 4.7 Noninverting Buck-Boost Converters. 4.8 Tapped-Inductor Buck-Boost Converters. 4.9 Summary. 4.10 References. 4.11 Review Questions. 4.12 Problems. 5 Flyback PWM DC-DC Converter. 5.1 Introduction. 5.2 Transformers. 5.3 DC Analysis of PWM Flyback Converter for CCM. 5.4 DC Analysis of PWM Flyback Converter for DCM. 5.5 Multiple-Output Flyback Converter. 5.6 Bidirectional Flyback Converter. 5.7 Ringing in Flyback Converter. 5.8 Flyback Converter with Active Clamping. 5.9 Two-Transistor Flyback Converter. 5.10 Summary. 5.11 References. 5.12 Review Questions. 5.13 Problems. 6 Forward PWM DC-DC Converter. 6.1 Introduction. 6.2 DC Analysis of PWM Forward Converter for CCM. 6.3 DC Analysis of PWM Forward Converter for DCM. 6.4 Multiple-Output Forward Converter. 6.5 Forward Converter with Synchronous Rectifier. 6.6 Forward Converters with Active Clamping. 6.7 Two-Switch Forward Converter. 6.8 Summary. 6.9 References. 6.10 Review Questions. 6.11 Problems. 7 Half-Bridge PWM DC-DC Converter. 7.1 Introduction. 7.2 DC Analysis of PWM Half-Bridge Converter for CCM. 7.3 DC Analysis of PWM Half-Bridge Converter for DCM. 7.4 Summary. 7.5 References. 7.6 Review Questions. 7.7 Problems. 8 Full-Bridge PWM DC-DC Converter. 8.1 Introduction. 8.2 DC Analysis of PWM Full-Bridge Converter for CCM. 8.3 DC Analysis of PWM Full-Bridge Converter for DCM. 8.4 Phase-Controlled Full-Bridge Converter. 8.5 Summary. 8.6 References. 8.7 Review Questions. 8.8 Problems. 9 Push-Pull PWM DC-DC Converter. 9.1 Introduction. 9.2 DC Analysis of PWM Push-Pull Converter for CCM. 9.3 DC Analysis of PWM Push-Pull Converter for DCM. 9.4 Comparison of PWM DC-DC Converters. 9.5 Summary. 9.6 References. 9.7 Review Questions. 9.8 Problems. 10 Small-Signal Models of PWM Converters for CCM and DCM. 10.1 Introduction. 10.2 Assumptions. 10.3 Averaged Model of Ideal Switching Network for CCM. 10.4 Averaged Values of Switched Resistances. 10.5 Model Reduction. 10.6 Large-Signal Averaged Model for CCM. 10.7 DC and Small-Signal Circuit Linear Models of Switching Network for CCM. 10.8 Family of PWM Converter Models for CCM. 10.9 PWM Small-Signal Switch Model for CCM. 10.10 Modeling of the Ideal Switching Network for DCM. 10.11 Averaged Parasitic Resistances for DCM. 10.12 Small-Signal Models of PWM Converters for DCM. 10.13 Summary. 10.14 References. 10.15 Review Questions. 10.16 Problems. 11 Open-Loop Small-Signal Characteristics of Boost Converter for CCM. 11.1 Introduction. 11.2 DC Characteristics. 11.3 Open-Loop Control-to-Output Transfer Function. 11.4 Delay in Open-Loop Control-to-Output Transfer Function. 11.5 Open-Loop Audio Susceptibility. 11.6 Open-Loop Input Impedance. 11.7 Open-Loop Output Impedance. 11.8 Open-Loop Step Responses. 11.9 Summary. 11.10 References. 11.11 Review Questions. 11.12 Problems. 12 Voltage-Mode Control of Boost Converter. 12.1 Introduction. 12.2 Circuit of Boost Converter with Voltage-Mode Control. 12.3 Pulse-Width Modulator. 12.4 Transfer Function of Modulator, Boost Converter Power Stage, and Feedback Network. 12.5 Error Amplifier. 12.6 Integral-Single-Lead Controller. 12.7 Integral-Double-Lead Controller. 12.8 Loop Gain. 12.9 Closed-Loop Control-to-Output Voltage Transfer Function. 12.10 Closed-Loop Audio Susceptibility. 12.11 Closed-Loop Input Impedance. 12.12 Closed-Loop Output Impedance. 12.13 Closed-Loop Step Responses. 12.14 Closed-Loop DC Transfer Functions. 12.15 Summary. 12.16 References. 12.17 Review Questions. 12.18 Problems. 13 Current-Mode Control. 13.1 Introduction. 13.2 Principle of Operation of PWM Converters with Peak-Current-Mode Control. 13.3 Relationship between Duty Cycle and Inductor-Current Slopes. 13.4 Instability of Closed-Current Loop. 13.5 Slope Compensation. 13.6 Sample-and-Hold Effect on Current Loop. 13.7 Current Loop in s -Domain. 13.8 Voltage Loop of PWM Converters with Current-Mode Control. 13.9 Feedforward Gains in PWM Converters with Current-Mode Control without Slope Compensation. 13.10 Feedforward Gains in PWM Converters with Current-Mode Control and Slope Compensation. 13.11 Closed-Loop Transfer Functions with Feedforward Gains. 13.12 Slope Compensation by Adding a Ramp to Inductor Current. 13.13 Relationships for Constant-Frequency Current-Mode On-Time Control. 13.14 Summary. 13.15 References. 13.16 Review Questions. 13.17 Problems. 13.18 Appendix: Sample-and-Hold Modeling. 14 Current-Mode Control of Boost Converter. 14.1 Introduction. 14.2 Open-Loop Small-Signal Transfer Functions. 14.3 Open-Loop Step Responses of Inductor Current. 14.5 Closed-Voltage-Loop Transfer Functions. 14.6 Closed-Loop Step Responses. 14.7 Closed-Loop DC Transfer Functions. 14.8 Summary. 14.9 References. 14.10 Review Questions. 14.11 Problems. 15 Silicon and Silicon Carbide Power Diodes. 15.1 Introduction. 15.2 Electronic Power Switches. 15.3 Intrinsic Semiconductors. 15.4 Extrinsic Semiconductors. 15.5 Silicon and Silicon Carbide. 15.6 Physical Structure of Junction Diodes. 15.7 Static I - V Diode Characteristic. 15.8 Breakdown Voltage of Junction Diodes. 15.9 Capacitances of Junction Diodes. 15.10 Reverse Recovery of pn Junction Diodes. 15.11 Schottky Diodes. 15.12 SPICE Model of Diodes. 15.13 Summary. 15.14 References. 15.15 Review Questions. 15.16 Problems. 16 Silicon and Silicon Carbide Power MOSFETs. 16.1 Introduction. 16.2 Physical Structure of Power MOSFETs. 16.3 Principle of Operation of Power MOSFETs. 16.4 Derivation of Power MOSFET Characteristics. 16.5 Power MOSFET Characteristics. 16.6 Mobility of Charge Carriers. 16.7 Short-Channel Effects. 16.8 Aspect Ratio of Power MOSFETs. 16.9 Breakdown Voltage of Power MOSFETs. 16.10 Gate Oxide Breakdown Voltageof Power MOSFETs. 16.11 Resistance of Drift Region. 16.12 Figures-of-Merit. 16.13 On-Resistance of Power MOSFETs. 16.14 Capacitances of Power MOSFETs. 16.15 Switching Waveforms. 16.16 SPICE Model of Power MOSFETs. 16.17 Insulated Gate Bipolar Transistors. 16.18 Heat Sinks. 16.19 Summary. 16.20 References. 16.21 Review Questions. 16.22 Problems. 17 Soft-Switching DC-DC Converters. 17.1 Introduction. 17.2 Zero-Voltage-Switching DC-DC Converters. 17.3 Buck ZVS Quasi-Resonant DC-DC Converter. 17.4 Boost ZVS Quasi-Resonant DC-DC Converter. 17.5 Zero-Current-Switching DC-DC Converters. 17.6 Boost ZCS Quasi-Resonant DC-DC Converter. 17.7 Multiresonant Converters. 17.8 Summary. 17.9 References. 17.10 Review Questions. 17.11 Problems. Appendix A Introduction to SPICE. Appendix B Introduction to MATLAB. Answers to Problems. Index.

734 citations

Journal ArticleDOI
TL;DR: This paper presents a single-phase cascaded H-bridge converter for a grid-connected photovoltaic (PV) application that offers other advantages such as the operation at lower switching frequency or lower current ripple compared to standard two-level topologies.
Abstract: This paper presents a single-phase cascaded H-bridge converter for a grid-connected photovoltaic (PV) application The multilevel topology consists of several H-bridge cells connected in series, each one connected to a string of PV modules The adopted control scheme permits the independent control of each dc-link voltage, enabling, in this way, the tracking of the maximum power point for each string of PV panels Additionally, low-ripple sinusoidal-current waveforms are generated with almost unity power factor The topology offers other advantages such as the operation at lower switching frequency or lower current ripple compared to standard two-level topologies Simulation and experimental results are presented for different operating conditions

728 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023379
2022869
20211,041
20201,621
20191,921
20182,096