Page 10 - Power Quality in Electrical Systems
P. 10
viii Contents
Chapter 4. Harmonics and Interharmonics 43
Background 43
Periodic Waveforms and Harmonics 43
Root-mean square 47
DC current 49
Pure sine wave 49
Square wave 49
DC waveform + ripple 50
Triangular ripple 50
Pulsating waveform 51
Pulsating waveform with ripple 52
Triangular waveform 52
Piecewise Calculation 52
Total Harmonic Distortion 53
Crest Factor 53
Summary 61
References 61
Chapter 5. Harmonic Current Sources 63
Background 63
Single-Phase Rectifiers 64
Three-Phase Rectifiers 69
The six-pulse rectifier 69
The twelve-pulse rectifier 70
High-Frequency Fluorescent Ballasts 71
Transformers 72
Other Systems that Draw Harmonic Currents 73
Summary 74
References 74
Chapter 6. Power Harmonic Filters 75
Introduction 75
A Typical Power System 76
IEEE Std. 519-1992 78
Line reactor 79
Shunt passive filter 81
Multisection filters 87
Practical Considerations in the Use of Passive Filters 95
Active harmonic filters 95
Hybrid harmonic filters 97
Summary 97
References 98
Chapter 7. Switch Mode Power Supplies 99
Background 99
Offline Power Supplies 100
DC/DC Converter high-frequency switching waveforms
and interharmonic generation 104
Testing for conducted EMI 106
Corrective measures for improving conducted EMI 107
