1 Introduction -- 2 Electric Power Quality -- 3 Unbalance -- 4 Harmonics -- 5 Transients -- 6 Sag, Swell, Interruption, Undervoltage and Overvoltage -- 7 DC Offset, Electric Noise, Voltage Fluctuation, Flicker and Power Frequency Variation -- 8 Unbalance Assessment using Sequence Components -- 9 Unbalance Assessment using Feature Pattern Extraction Method -- 10 Useful Tools for Harmonic Assessment -- 11 Harmonic Assessment using FPEM in V-V and I-I Planes -- 12 Clarke and Park Transformation -- 13 Harmonics Assessment by FPEM in Clarke and Park Planes -- 14 Harmonic Assessment by Area Based Technique in V-V and I-I Planes -- 15 Harmonic Assessment by Area Based Technique in Clarke and Park Planes -- 16 Assessment of Power Components by FPEM and ABT -- 17 Transients Analysis -- 18 Passivity and Activity Based Model of Polyphase System.