A propagating wave on a transmission line undergoes multiple reflections at_____________?
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Answer: D. sending and other end
Explanation
Travelling waves on a transmission line experience reflections at both the receiving load end and the sending end. Discontinuities in surge impedance at terminal points cause voltage and current waves to bounce back. These multiple reflections create complex transient voltage oscillations along the length of the transmission line. A surge propagating along a transmission line encounters impedance mismatches when reaching terminal equipment. Reflection coefficients determine the amplitude and polarity of the reflected voltage and current waves. Open circuits cause voltage waves to double upon reflection, whereas short circuits invert the voltage wave.
Power system engineers analyze travelling wave reflections to protect equipment from dangerous temporary overvoltages. Understanding wave propagation is essential for designing insulation coordination schemes in high-voltage networks. Surge protective devices help dampen multiple reflections before they damage terminal transformers and generators. Limiting reflections to only tapping points ignores the significant reflections occurring at terminal loads. Focusing solely on the load end neglects the boundary conditions and reflections happening back at the sending end. Stating sending end only ignores the fundamental reality that reflections occur at both ends of the line.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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