Hello,
As far as I understand, a transmission line is simply a wave-guide for TEM modes.
If the waves are propagating in the z direction so Hz=Ez=0. How does this fact leads to the conclusion that in any transverse plane (xy plane) the fields are conservative?
Thanks a lot.
Hi Guys,
I looked so hard on the net, trying to understand something that I am struggling with for the whole day, but I ended up frustrated.
I am working on my design project and was assigned a part conecnred with antennas, I am using the Antenna Theory Analysis and Design by Balanis to...
Homework Statement
A transmission line has the following properties:
L_{0} = 1 mHm^{-1}
C_{0} = 10 \mu F m^{-1}
R_{0} = 10 \Omega m^{-1}
G_{0} = 0 \Omega^{-1} m^{-1}
That is, inductance per meter, capacitance per metre etc. The line is 10m long.
The problem is to find the...
Asmall power plant produces a voltage of 6.0kV and a current of 150A. The voltage is stepped up to 240kV by a transformer before being sent to a substation. The resistance of the transmission line between the power plant and the substation is 75 ohm. How much is the current flowing in the...
I understand that reflected waves on a transmission line are a result of the constraints of Ohm's Law and Kirchhoff's Law at the transition points.
However, I'm having trouble visualizing the physical cause for this. What is actually causing the electrons to flow in the opposite direction...
Homework Statement
A transmission line consists of a cylindrical conductor of radius r at a distance d in air from a conducting plane (r >>d).
Derive the capacitance per unit length C and the inductance per unit length L and
check that 1/sqrt(LC) = c.
Homework Equations
The...
If a single conductor in a transmission line dissipates 6,000kWh of energy over a 24 hour period during which time the current in the conductor was 100 amps. What is the resistance in the conductor.
So could I just conver the kWh of energy to kW by dividing by 24 hours...than just use ohms...
Homework Statement
Design a dc transmission line that can transmit 225 MW of electricity 185 km with
only a 2.0% loss. The wires are to be made of aluminum and the voltage is 660 kV.
2. Homework Equations
P= IV = I^2 * R
R= p(L/A)
Power loss = Pf - Pi
Attempt at a solution
I worked through...
I am studying EM wave and transmission lines. I see both derive equations for propagation constant \gamma:
Plane wave velocity is 1/\sqrt{\mu\epsilon} and \eta = \sqrt{\mu/\epsilon}
Transmission line velocity is 1/\sqrt{LC} and Z0=\sqrt{L/C}.
From that the book just to say the velocity...
Hello everybody,
I have a question and I am wondering if you can help me find an answer. The problem I am trying to figure out is:
I have 400 miles of 345 kV transmission line. An outage happened twice in two different locations on the line caused by two different lightning strikes, a 35kA...
I think pretty much everybody knows the length of the transmission line should be less than the wave length of the RF signal.
How do you explain it to some one who is not from engineering background.
I myself can't get it some times.
Say for example the wavelength of a wave is
2" =...
Z in =50-j10 Ohms
i in=2 amps
length = 2 meters
Z0=75 Ohms
u=2E8 meters per second
beta=.3 rad/m
How do I find I+ and I- at the input?
What is the voltage at the load?
Any help would be appreciated.
How is signal transmission speed determined in a transmission line? For example, what determines how long it takes a single pulse to go from one end of a line to the other end. I would assume it depends directly on the conductivity of the material from which the line is made but I'm not sure...
Hello everyone ,
I am still new to the protection field so i would appreciate if you can help me with analysis of the following,
A 13.8 Kv OHTL was cut and fell on ground , the cable was still live although being protected by Earth fault relays and Over current relays(Instantaneous and...
Hello All,
I have two PCBs, board A and board B. Board A has a 50MHz Crystal that I am making available through a high speed digital isolator (IL711-2E) to a chip that is on board B.
Here's the datasheet on the isolator IC http://www.nve.com/Downloads/il711-2.pdf".
Now, I was thinking about...
Is it true that lossless transmission lines don't distort signals?
to me, they seem like low pass filters.
i had this class a while ago, but I guess i forgot this, or never understood it
thanks
If I have a section of transmission line, with a characteristic impedance Z0, how does the standing wave ratio in that section change as a function of the frequency of operation?
Doesn't the stading wave ratio just depend on the characteristic impedance of the line, and the load impedance?
Can I first find the input impedance relative to the segment nearest to the load, then use the found input impedance as the load in next iteration? Or can I add the characteristic impedances, since they are sort of in series?
I'm looking at a lossless transmission line where the load is a resistor, and the input is a step. The source resistance is zero, and the system has reached steady state.
So in this case, what happens when the source is switched off? You'd have the resistor on the right, and to the left of...
In all the source I have read about, EM field analysis of Transmission Lines always assume the conductor is perfect (infinite conductivity), and that simplify a lot the analysis, since there can be no field inside the conductor and that gives much easier boundary condition, which allows us to...
-A transmission line has a resistance of 5 ohms. Calculate the power loss in the line when 10 000 kW are transmitted at 10 kV...
I don't know where to start, what formula am I supposed to use? I'm sure the second I find out its going to be soo easy, but any help would be apreciated.
Thanks...
Hi,
I want to clarify some notiona in an antenna. The major components of an antenna are a generator, transmission line and an antenna (dipole). Let's say the whole system has a perfect matche, i.e. the dipole is about 70 ohms as the transmission line. If my generator ,the output voltage, is...