Transmission line Definition and 184 Threads

Hi, I realized 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 realized that from source to load the electrons in an AC line don't actually move anywhere. (as far as I know) Yet if...

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...

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...

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...

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.

Hi guys. I'm looking into the modelling of a transmission line model (TLM) and feel that I'm understanding it fairly well. Although, one parameter keeps popping up with very little explanation as to what it actually is. It seems that to characterize contact resistance for a e.g. GaAs TLM with...

Hi guys. I'm looking into the modelling of a transmission line model (TLM) and feel that I'm understanding it fairly well. Although, one parameter keeps popping up with very little explanation as to what it actually is. It seems that to characterize contact resistance for a e.g. GaAs TLM with...

Hello. I have questions for transmission line and please see the image below. This is the circuit what I made in which ZO and ZL are output and load impedances, respectively. The commercial voltage probe with oscilloscope is used to measure VL, voltage over ZL . VO, the voltage difference...

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...

Dear all, I am simulation a lossy transmission line like this: http://www.ece.uci.edu/docs/hspice/hspice_2001_2-2878.jpg with G having zero conductance (open). So it is a standard lossy transmission line with RLC components. All R, L, and C values are the same, so there is no variation from...

Hello In this problem I tried to find the voltage at 2Z0 (load) that is (landa/4) from generator.My result it is different from teacher's result.what is my mistake? (I named V1e as A point and V2e as B point so the voltage across the B point is (Vs/4) according to Zin=Z0 that is the same as Z0...

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...

Homework Statement An ideal transmission line is terminated with a load impedance of 90 ohms and has a characteristic impedance of 50 ohms. Why does it's S11 response trace out a circle on the smith chart? Homework Equations Z_{\text{in}}=Z_0\frac{Z_0+j Z_L \tan(\beta l)}{Z_L+j Z_0 \tan(\beta...

Homework Statement A transmission line has the primary coefficients R= 2 ohm/m, L=8 nH/m, G= 0.5 mS/m and C= 0.23 pF/m. Determine the lines secondary coefficients Zo, α and β at a frequency of 1 GHz. Homework Equations ω= 2 π f See uploaded formulas document The Attempt at a Solution I'm not...

Dear friends 1.What is wind span ,wight span and normal span, and what is the difference. 2. Factory acceptance test. FAT. For towers what is that meaning and what is necessary test to be require to do or check. Thanks

Hi , I'm studying transmission lines and how waves move through the device , so far I haven't delved into the maths behind it as I have been trying to get an overview of it.So far I have seen the effects when there is an open circuit , shorted and matched impedance loads. The example I saw...

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...

hi friends. I am new for transmission 132kv project. For transfer 100MW power about 95km line. 1. I want to know what is short ckt current and how to calculate it. 2. load breaking current Your kind help required thanks.

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...

Homework Statement I would like to define pressure loses through transmission line to the transducer. In transmission line I have a reducing union, filter and L pipe. How I can find this differences? In case of frequency my reducing union reduce pipe diameter 6 mm to 3 mm how i can determine...

When wave is reflected back means power is reflected back and not all power is consumed at the load. But I am thinking if I placed the load at the position of Vmax (of the stationary wave formed by the incident and reflected wave). Isn't that all the power will be dissipated at the load, so...

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 =...

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...

I was reading textbook and felt confused about this-- when trying to deal with inner inductance of transmission line, only the fraction (x/r)^2 of total current, which interlock with magnetic lines should be considered. However, isn't the inductance or even flux linkage an intermediate...

Homework Statement (a) A transmission line has a length, ℓ, of 0.4λ. Determine the phase change, βℓ, that occurs down the line. (b) A 50Ω lossless transmission line of length 0.4λ is terminated in a load of (40 + j30) Ω. Determine, using the equation given below, the input impedance to the...

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...

Hi, I was wondering if it would be possible for someone to help me clarify a few things regarding transmission lines and transformers? For a Power Transmission line, what exactly is the mutual coupling between phases of a 3 phase line? Is this the same as the shunt capacitance and if not...

Hi, if I simulate a three phase transmission line operating with a fault across two of the phases, would the mutual coupling have any effect on the current through each of the lines, as I have calculated the fault current values using symmetrical component analysis and the values are...

I need to figure out if my companies pulling equipment can handle a 795 drake conductor (about 1 lb/ft) double bundled (times 2). The pulling equipment has a safe working load of 4000 lbs. We are pulling it across 16 spans with a average span of 674 feet. the towers are 115' tall. Max sag...

Hi guys, I was playing around with conductor configurations and observed this phenomenon. Mind you these are for the High voltage transmission (138 kV) lines that span kms. So apparently, the orientation of the conductor relative to North will change the ampacity of the transmission line. Can...

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: V_S = V_R (A_1+jA_2)+I_R (B_1+jB_2) I_S = V_R(C_1+jC_2)+I_R(D_1+jD_2) where 'S' stands...

Hello to experts! What is impedance inversion in quarter wave transformer? I need definition not a concept, not explanation, not description. But a precise and point definition. Thank you very much.

Homework Statement A lossless transmission line with characteristic impedance Z0 = 50Ω , β = 5∏x10-3, and length l =80 meters, is terminated into a load ZL = 80Ω. The transmission line is powered by a source with 120 V and ZG = 12 Ω. Calculate the load voltage. Homework...

Hello. I need to derive this equation (attached), can you help me please? That's the equation for a two-pair terminal medium-distance power transmission line (20~100km). I have no idea how to start it. Can someone guide me, please?

Homework Statement As seen in picture: A coaxial transmission line has a characteristic impedance of 50 Ω, propagation velocity of 200m/μs, length of 400m, and is terminated by a load resistance, RR = 16.7 Ω. At the sending end the line is connected to a pulse generator that has an...

Homework Statement Incase formatting of numerical answers below is weird, please see attached picture of question. "Consider a distortionless transmission line with impedance 50 Ω, capacitance 0.1 nF/m and attenuation 0.01 dB/m. Find: (a) the resistance, inductance and conductance of...

In wikipedia, it said for optical fiber, a loss that takes place at discontinuities of refractive index, especially at an air-glass interface such as a fiber endface. At those interfaces, a fraction of the optical signal is reflected back toward the source. But what I learned in tranmission...

Hey all, Refer to page 5 in the pdf in the link (http://whites.sdsmt.edu/classes/ee481/notes/481Lecture26.pdf) I am having a little bit of a hard time understanding a portion of a derivation. You will notice that when determining the ABCD paramters of the shunt stubs they merely use A=1...

A 50 ohm transmission line is terminated with 60 ohm and 30 ohm resistors in parallel. The voltage at the input to the line is V(t) = 100 cos (5X10 ^ 9 t) and the line is 3/8 th of a wavelength long. What average power is delivered to each load resistor ? My ans is getting 81.6 but actual...

I have been reading up on transmission lines and I was wondering: If a transmission line has high dielectric loss (low conductance, G) does this have any effect on the velocity factor? I would think that it would reduce the velocity factor because some of the energy would be absorbed by...

Homework Statement A 230kV, 160km long transmission line has the following parameters expressed on a 230kV, 100MVA base. R = 0.0151 X = 0.1476 Y = 0.288 The sending end voltage of the line is held constant at 1.0 pu. The load at the receiving end has a lagging power factor of 0.8...

Hi, I'm building a Yagi antenna for the 440Mhz ham band. The outline I'm following uses a driven element of a folded dipole; Z = around 288 ohms. I am feeding this with 50 ohm source. Many internet sources describe a balun made from a 1/2 wave length coax (velocity factor adjusted). I will...

https://www.physicsforums.com/attachments/66302Two-conductor transmission line, find the potential difference V of the two conductors.? Two-conductor transmission line. At point P (x=43 cm, y=32 cm) in Fig. 2-10, |E|=450 V/m. If s=25 cm, h=29 cm, and r=12.5 cm, find the potential difference if...

Homework Statement A factory receives 120kW of power from a power station 20km away via transmission lines. If the resistance in the power lines is 0.5Ω/km, what is the power loss in the lines if the electricity is transmitted at 100kV (Approximate to a simple DC circuit). Homework Equations V...

Homework Statement Find the general solution for the current I(z,t) associated with the voltage V(z,t).Do this by substituting [1] into [2] and [3], integrate with respect to time, and then take the derivative with respect to z. Homework Equations V(z,t)= f+(t-z/vp) + f-(t+z/vp) [1]...

Homework Statement Attached is the problem. I am a little confused as to how I should be approaching this type of problem. If I Determine the input impedance for the first segment of transmission line and load impedance on the right, is that going to be in parallel with Z_L on the left? I am...

Hello i would like to know what is the different between 300km and 150km in transmission line.. thanks

Homework Statement Hey guys. I have a transmission line with a known characteristic impedance (50 Ω) of length L that is connected to an antenna that has a complex impedance of (50-j25)Ω. I am having extreme difficulty determining the minimum length (expressed in wavelengths) of line such...

Hi, I've been coming to physicsoforums for years, I love the community! This might be my first post though. I am wondering what the impedance is of a transmission line with a matched stub on the end. The impedance of the line is 50 Ohms, and the impedance of the stub is 50 Ohms. Is the...

I am simulating an unshielded twisted wire pair of a communication network, Controller Area Network. Bus Speeds taken into consideration are 250/500/1000/2000 kbps. Depending on the physical dimensions of the wire and insulation dielectric constant, I have computed the R,L,C,G parameters...