Read about transmission line | 24 Discussions | Page 1

  1. Amartansh

    I Intuition behind fields in Transmission lines

    How can travelling wave exist on transmission line if wires are perfect conductors (how voltages can be different at different positions on one perfect conductor)? I mean electric fiels should be zero on equipotential source. I know if length is too long compared to wavelength, we get phase...
  2. A

    Active power dissipated by a resistor from DC to RF

    Hello all PF members! I was wondering about the power dissipated by resistor at high frequency which is: ##P=Re\left \{ U\cdot I^{*} \right \}=Re\left \{ \frac{\left |V^{+} \right |^{^{2}}}{2\left |Z_{c} \right |}\cdot (1-\left |\Gamma \right |^{2} )\right \}##, (1) where: ##Z_{c}## -...
  3. Jason-Li

    Transmission Line Coefficients

    Homework Statement Figure shows a 50 Hz, high-voltage, transmission line. The relationships between the sending and receiving end voltages and currents are given by the complex ABCD equations: where 'S' stands for sending-end and 'R' stands for receiving-end (a) Given the parameter values...
  4. Cocoleia

    Power loss in a transmission line

    Homework Statement Homework Equations The Attempt at a Solution I have posted the whole solution so it is more complete, but I really only need help with part c (I think) My output power is higher than my input power, I'm not sure where I'm going wrong
  5. G

    Transmission line: leakage current differential equation

    Homework Statement I have a coaxial cable with internal conductor of radius r1 and external conductor of radii r2 and r3. The material of the conductors has a conductivity ##\sigma_1##. Between the conductors there is a imperfect dielectric of conductivity ##\sigma_2##. Consider the...
  6. Marcus95

    Input impedance of a "Ladder" transmission line

    Homework Statement My electronics&physics lecture notes contain the following side note: ___ "A ladder transmission line comprises an alternating sequence of segments of two different transmission lines both of length $l$ with characteristic impedance $Z1$ and $Z2$. If the line is constructed...
  7. Marcus95

    Power Transmitted in a Coaxial Cable

    Homework Statement A coaxial transmission line consists of an inner cylindrical conductor of radius a = 1 mm and a cylindrical outer conductor chosen to make the characteristic impedance 75 ohm. The space between the conductors is lled with a gas which can stand a maximum eld of 105 V/m without...
  8. A

    Calculating the reactive power of a transmission line

    I have a single machine connected to an infinite bus with the following parameters: - Sending end power = 3.75MW - RL=5.18 ohms - XL=130 ohms - VS (Generator bus)=161kV - VR (Infinite bus)=161kV - Sending end voltage angle (delta) = 0.01877 (Angle which allows 3.75MW to be transferred)...
  9. B

    Losses on Power Transmission Lines

    Say a power station transmits 1008 MWh of power per year to a facility however they only receive 900 MWh say the transmission line is 15 km long how would you calculate average power loss per km, now I know that theoretically it will just be 7.2 MWh per km but what calculations would you make to...
  10. C

    I What really is bandwidth?

    Hello, I am reading a book about simulation, modeling and automatic control. In a chapter about hydraulic transmission line, a pipe's "bandwidth" is mentioned. Contex: "Long pipes are used in large hydraulic installations where pipes of length up to 10 m are not uncommon. Moreover, in offshore...
  11. Manoj Sahu

    Does the neutral conductor carry current during normal working condition in a house?

    I read in a book that during normal working condition (balanced system) the current through a neutral conductor is zero i.e., Ia+Ib+Ic =0 where Ia, Ib, Ic are phase current of three different phases a, b, c. How is that possible? I mean if you look at mathematical result of the phases they are...
  12. I

    Backward Impedance Matching

    Homework Statement Homework Equations The Attempt at a Solution 1) I determined the input impedance of the first transmission line (Zin1). 2) I calculated...
  13. B

    Lossless transmission line characteristic phase constant

    Homework Statement A lossless transmission line has an inductance of 9.0 nH / m and a capacitance of 3.6 pF / m. a) What is the line's characteristic impedance? b) Calculate the phase constant of a frequency of 1 GHz. Homework Equations Equation of characteristic impedance of a transmission...
  14. T

    Current of AC transmission lines and electricity in general

    Hi, I realised I didn't understand the physical model of something I know the theory of pretty well. I was considering the real power loss of an AC transmission line I2*R, then I realised that from source to load the electrons in an AC line don't actually move anywhere. (as far as I know) Yet if...
  15. M

    I Dispersion relation of a transmission line - questions

    Hi, I have transmission line with dispersion relation ω=sin(kx), so then means that for one value of ω I have two values of k. I apply voltage with some frequency with is allowed to move in the line. First question is, how can I influence what k will be generated inside the line. The another...
  16. GhostLoveScore

    Transmission line radiation

    This question is about transmission line that I use between my Ham radio and the antenna. We a transmission line that is made of two parallel conductors close together. The current in one conductor is exactly the same as the current in the other conductor, but flowing in opposite direction...
  17. B

    Transmission line and infinite reflection coefficient

    Hello, I am taking some microwave engineering courses and was trying to explain the concept of reflection coefficients to my friend, but he asked me a question I am unable to answer.... So we know that given a transmission line with characteristic impedance Z_0 terminated with a load impedance...
  18. tech99

    Transformer core considered as a waveguide

    Has anyone considered the iron core of a transformer to act as a transmission line or waveguide, where it conveys energy from primary to secondary? The core seems to resemble a "magnetic version" of the single wire Goubau line.
  19. N

    CMOS to Microstrip Impedance Matching

    I need to somehow take the output of a CMOS IC and transmit that signal over a 50 Ohm Microstrip line. The output impedance of the CMOS IC is about 15 megaohms. I see a lot of examples for going from 75 ohms to 50 ohms or similar but nothing on something of this magnitude. Any ideas? CMOS...
  20. Cedric Eveleigh

    Calculating current distribution in a HF coaxial cable?

    Hello, I would like to calculate the current distribution in a coaxial cable where the skin effect is significant. I asked this question on stackexchange and I provided pictures and more details there...
  21. neduet

    Selecting conductors for transmission line 132kv 100MW 95km

    Hello dears i want to know which is best for 132kv transmission line. advantages and disadvantages as in prectical use. but also consider economical factor wisely . what you chose if you are in my place... ACSR Conventional AAAC ( All Aluminium Alloy Conductors ) ACCC Aluminum Conductor...
  22. G

    Impedance matching of transmission line to source impedance

    Hello I'm now studying transmission line theory. I got to know how impedance matching between characteristic impedance of transmission line and electrical load is important to achieve maximum power transfer and minimize power reflection which causes danger for the system. But the textbook...
  23. B

    Transmission line Voltage loss

    Ok I do not know if I am right about this but : if you have an AC 120 V 60Hz generator connected to a wire of Length L(1000KM) and Resistance R going to a motor down a well, to know if you will have Voltage loss you do λ = C / F C is the speed of Light = 299 792 458 m/s F is the 60Hz λ =...
  24. F

    Determine attenuation of voltage in transmission line

    Hello, So I have a circuit where I input a square pulse with a source impedance and load impedance (which are just pure resistors) each of which can be varied and a transmission line circuit connecting them which is made up of resistors, capacitors, inductors in a lumped element model. I set...