Traveling waves and reflections on transmission lines
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- čas přidán 20. 11. 2021
- Go the the simulator yourself: www.ecsp.ch. This video explains the phenomena of traveling waves on transmission lines and the reflections at line ends. You can find more videos on: / @georgschett801
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Amazing
Hi Georg,
thanks a lot for the nice video. What if the switch is at the end of line and it opens (instead of closing the switch)? For ac systems, I mean (50 Hz for example).
Do you have any short video on that?
Thank you.
Kind regards,
Amir
Why don't you try to find the answer by using the simulator? The free version is available and you can build a simple L-C model of a line.
why is voltage doubled if end of the line is open?
did you figure this out?
Conservation of energy
Travelling at 2/3 c not c.
I am not sure that this is right. As long as there is no dielectric media, the speed is close to c. In cable however, where the conductor is surrounded by a dielectric material, the speed is lower.
@@georgschett801 if we talk calssical transmission line, differential mode (differential voltage and current) then it's 2/3 c. If we talk waveguide mode (e.g. surface waves propagating at the interface of conductor and air) then 0.9x c.
@@georgschett801 nonetheless great visualisation and great video
@@georgschett801 one exception and after a bit of thought - you might be able to make a coaxial cable with aerogel type of filler, then you may get very close to c. Parallel wires radiate and couple to surroundings... hence even if wires are uncoated you cant assume dielectric free setup... hope this helps
@@outrospection4all Maybe there is a misunderstanding. When I am talking about transmission lines, it is about free standing the 3-phase high voltage power lines (50 / 60 Hz) without dielectric insulation material. In this case most of the modes are traveling at close to light speed. At very high voltage there is an additional corona damping effect which slows the propagation a little but normally this effect is not considered except for lightning protection studies. You may be addressing wave guides or micro strip transmission lines which are operated at much higher frequencies and where there can be dielectric material involved. It is also called transmission lines. Anyway: thanks for your feedback!