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When a wave propagates on a transmission line, it suffers reflection several times at
Load end
Sending end
Sending end and other end
Tapping point
Sending end and other end
When a traveling wave propagates along a transmission line, it undergoes reflection at any point where the surge impedance changes. Since both the sending end and the load end typically represent discontinuities in impedance, the wave is reflected back and forth between these terminals until it is attenuated.
When a traveling wave propagates along a transmission line, it undergoes reflection at any point where the surge impedance changes. Since both the sending end and the load end typically represent discontinuities in impedance, the wave is reflected back and forth between these terminals until it is attenuated.
╬У=Z2тАЛ+Z1тАЛZ2тАЛтИТZ1тАЛтАЛ тАФ Reflection coefficient formula at a junction with impedance change
VreflectedтАЛ=╬УVincidentтАЛ тАФ Relation between incident and reflected voltage waves
The reflection coefficient is determined by the ratio of the change in impedance at a junction. At the load end (ZLтАЛ), the reflection coefficient ╬УLтАЛ=ZLтАЛ+Z0тАЛZLтАЛтИТZ0тАЛтАЛ governs the reflected wave. Similarly, at the sending end (ZSтАЛ), the wave reflects based on ╬УSтАЛ=ZSтАЛ+Z0тАЛZSтАЛтИТZ0тАЛтАЛ. Successive reflections occur as the wave travels between these two boundaries, leading to the formation of a lattice diagram of transients.
Reflection occurs due to impedance mismatch at line boundaries.
The sending end is considered an impedance boundary, typically the source impedance.
Multiple reflections can cause overvoltages, requiring surge protection at both ends.
A lattice diagram is used to analyze the multi-reflection process over time.
Helps in understanding transient voltage distribution
Essential for insulation coordination and equipment protection
Complex analysis required for lines with multiple sections
High-frequency oscillations can stress terminal equipment insulation
Power system protection (Surge Arresters)
Fault location in underground cables (TDR technology)
The transient behavior persists until the energy is dissipated through line resistance.
Option D is incorrect because while reflection happens at a tapping point (if impedance differs), it is not the primary location for systemic end-to-end reflections.
C is correct тАФ Reflections occur at any impedance discontinuity, and in a transmission line, the sending end and load end act as primary boundaries for these reflections.
Always remember that in transient analysis, the reflection coefficient at an open-circuited end is +1 and at a short-circuited end is -1.