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The industry's widespread application of variable speed drives in the recent years accompanied by the electric utility's increasing use of capacitor banks have set the basis for paying considerable attention to the quality of electric power and seriously addressing the issue of current and voltage distortion, a major form of which is harmonic distortion. Harmonic studies are aimed at computing bus harmonic voltages, branch harmonic currents, and voltage and current total harmonic distortion (THD), as well as detecting resonance conditions. It is thus of great importance, when conducting harmonic studies, that system components are correctly mod elled to ensure accurate and reliable harmonic distortion results. Commercial programs are available for the analysis of harmonic problems. International standards are further being developed to assess harmonic distortion. Chapter 2 of this text provides some preliminaries. Characteristics of harmonics and measures of harmonic distortion are illustrated. The use of capacitor banks for reactive power supply and power factor correction is dis cussed. Resonance is explained. Origins of harmonic distortion are dealt with in Chapter 3. Chapter 4 is aimed at quantifying the effects of harmonic dis tortion on power system equipment and loads. Chapter 5 is devoted to the methods of reduction of power system harmonics. Limits of allowable voltage and current harmonic distortion set by IEEE, IEC, EN and NORSOK stan dards are presented in Chapter 6.
Sommario
1. Introduction.- 2. Fundamentals of Harmonics.- 3. Harmonics in Power Systems - Their Causes.- 4. Effects of Harmonic Distortion on Power Systems.- 5. Mitigation of Power System Harmonics.- 6. Limits of Harmonic Distortion.- 7. Harmonic Studies - Modelling of System Components.- 8. Transformer Modelling.- 9. Modelling of Transmission Lines / Cables.- 10. Power System Harmonic Studies - A Simple Approach.- Appendices.- A. A Review of Transformation and Symmetrical Components.- A.2 Symmetrical Components.- B. Phase and Sequence Admittance Matrices for Three-Phase Transformers.- B.2.1 Yd1 Transformers.- B.2.2 Yd3 Transformers.- B.2.3 Yd5 Transformers.- B.2.4 Yd7 Transformers.- B.2.5 Yd9 Transformers.- B.2.6 Yd11 Transformers.- B.4.1 Dyl Transformers.- B.8 Y-Y Transformers.- B.8.1 Yy0 Transformers.- B.8.2 Yy2 Transformers.- B.8.3 Yy4 Transformers.- B.8.4 Yy6 Transformers.- B.8.5 Yy8 Transformers.- B.8.6 Yy10 Transformers.- B.9.1 Dd0 Transformers.- B.9.2 Dd2 Transformers.- B.9.3 Dd4 Transformers.- B.9.4 Dd6 Transformers.- B.9.5 Dd8 Transformers.- B.9.6 Dd10 Transformers.- B.10 Summary.- C. Transmission Matrices for Three-Phase Transformers.- C.1.1.1 Yd1 Transformers.- C.1.1.2 Yd3 Transformers.- C.1.1.3 Yd5 Transformers.- C.1.1.4 Yd7 Transformers.- C.1.1.5 Yd9 Transformers.- C.1.1.6 Yd11 Transformers.- C.1.2.1 Dy1 Transformers.- C.1.2.2 Dy3 Transformers.- C.1.2.3 Dy5 Transformers.- C.1.2.4 Dy7 Transformers.- C.1.2.5 Dy9 Transformers.- C.1.2.6 Dy11 Transformers.- C.1.3 Summary.- C.2.1 Yy0 and Dd0 Transformers.- C.2.2 Yy2 and Dd2 Transformers.- C.2.3 Yy4 and Dd4 Transformers.- C.2.4 Yy6 and Dd6 Dz6 Transformers.- C.2.5 Yy8 and Dd8 Dz8 Transformers.- C.2.6 Yy10 and Dd10 Transformers.- C.2.7 Summary.
Riassunto
The industry's widespread application of variable speed drives in the recent years accompanied by the electric utility's increasing use of capacitor banks have set the basis for paying considerable attention to the quality of electric power and seriously addressing the issue of current and voltage distortion, a major form of which is harmonic distortion. Harmonic studies are aimed at computing bus harmonic voltages, branch harmonic currents, and voltage and current total harmonic distortion (THD), as well as detecting resonance conditions. It is thus of great importance, when conducting harmonic studies, that system components are correctly mod elled to ensure accurate and reliable harmonic distortion results. Commercial programs are available for the analysis of harmonic problems. International standards are further being developed to assess harmonic distortion. Chapter 2 of this text provides some preliminaries. Characteristics of harmonics and measures of harmonic distortion are illustrated. The use of capacitor banks for reactive power supply and power factor correction is dis cussed. Resonance is explained. Origins of harmonic distortion are dealt with in Chapter 3. Chapter 4 is aimed at quantifying the effects of harmonic dis tortion on power system equipment and loads. Chapter 5 is devoted to the methods of reduction of power system harmonics. Limits of allowable voltage and current harmonic distortion set by IEEE, IEC, EN and NORSOK stan dards are presented in Chapter 6.
