Harmonic generation in transformers is primarily caused by_______________?
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Answer: D. saturation of core
Explanation
Magnetic core saturation occurs when high excitation pushes the iron core beyond its linear magnetization limit. Non-linear magnetic behavior flattens the peak of the mutual flux waveform, introducing severe harmonic components. The third harmonic and its multiples are the most prominent distortion products generated by iron core saturation. Transformer iron cores utilize ferromagnetic materials with non-linear B-H curves to concentrate magnetic flux. Higher voltage levels or overexcitation drive the operating point deep into the saturation region of the steel core. Harmonics distort sinusoidal voltage and current waveforms, leading to increased transformer heating and communication interference.
Fluctuating loads cause voltage drops and thermal variations but do not directly generate continuous magnetic core harmonics. Poor insulation leads to dielectric breakdown and short circuits rather than generating steady-state waveform harmonics. Mechanical vibrations result from magnetostriction forces but are a symptom rather than the primary cause of harmonics.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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