Modeling coaxial cable impedance

[student52]

Hi,

I am trying to model electrical equivalent of a coaxial cable. The data I have is
1. Conductor resistance
2. Insulator resistance
3. Partial discharge
4. Insulation Thickness
5. Overall diameter

Actually I planned to use an equivalent circuit that has series connection of inductance and resistance parallel to a capacitor (Check the diagram shown below).Infact I am surprised to see quite different circuit here. With the data I have what circuit should I use? Kindly explain which of these circuits is apt.


--------inductance-------resistance-----
|
|
|
c
a
p
|
|
--------------------------------------|


P.S. I don't have data about inductance

Thanks in advance,

Regards.

 

[berkeman]

Hi,

I am trying to model electrical equivalent of a coaxial cable. The data I have is
1. Conductor resistance
2. Insulator resistance
3. Partial discharge
4. Insulation Thickness
5. Overall diameter

Actually I planned to use an equivalent circuit that has series connection of inductance and resistance parallel to a capacitor (Check the diagram shown below).Infact I am surprised to see quite different circuit here. With the data I have what circuit should I use? Kindly explain which of these circuits is apt.


--------inductance-------resistance-----
|
|
|
c
a
p
|
|
--------------------------------------|


P.S. I don't have data about inductance

Thanks in advance,

Regards.

Welcome to the PF.

Transmission lines are generally modeled using the "Telegrapher's Equations" as described in this link:

http://en.wikipedia.org/wiki/Transmission_line

Are you wanting to model your coax differently?

 

[student52]

Hi,

I wanted to know in what cases a cascaded equivalent should be used? I want to make sure in what cases should I use a lumped model and in which cases distributed model.