Q2Power Quality and FACTS
Question
2 marks
Q.2. What do you mean by harmonics? [2]
Answer
Harmonics are sinusoidal voltages or currents having frequencies that are integer multiples of the fundamental power system frequency (e.g., 100 Hz, 150 Hz for a 50 Hz system). They combine with the fundamental to produce a non-sinusoidal, distorted waveform.
Harmonics are mainly generated by non-linear loads such as rectifiers, inverters, arc furnaces, and switch-mode power supplies. Their severity is quantified by Total Harmonic Distortion (THD), and they cause overheating of transformers/cables, capacitor bank resonance, and mal-operation of protective relays.