Cable Inrush current

[giordanonaval]

Hello
I need to know how is the inrush current wave of a no loaded cable 1x150 mm² (300 MCM), 4.16 Kv, 29 Km (18 Mi), 60 Hz.
I undertand the first ones cicles have a high frequency, but i have not idea which is that freq.
Can anyone help me.

Sorry about my english

Thanks in advance

Martin

 

[davidbeach]

Highly variable; you will need to run EMTP studies to find your answer.

 

[giordanonaval]

Actually I run ATP, but I´m not sure if the result is correct. The ATP "cut" the peaks of the current. I think that is incorect.
I attach a current graphic and a zoom where you can see how the peaks are cut.

thanks in advance

Martin

 

[giordanonaval]

Here is the Zoom.

 

[davidbeach]

That looks like an inrush current to me. You have multiple frequencies due to various inductances and capacitances as well as reflected waves from the far end of the cable.

 

[ijl]

It looks like inrush current with current oscillating between the ends of the cable, as davidbeach writes. But the transient (the calculated curve) is so complicated, that it is not possible to say more about it without knowing more about the network and cable. One should know, what components are connected to the ends of the cable, how the switching is done, what are the capacitance and inductance per unit length of the cable, etc.

But one needs a very fast switching for a transient of this type, and this raises questions like: What is the purpose of this study? Is this curve realistic or even important?