How to determine surge impedance by sequence impedances? 1

[Tofeil]

Dear friends
I calculated transmission line's sequence impedance (positive, negative and zero) by tower and conductor configuration in MATLAB Powergui toolbox. I want to determine the line surge impedance ( Zc=√(L/C) *). I have L0 , L1 , C0 , C1 but I don't know, how to determine L and C by L0 , L1 , C0 , C1. please guide me.
I am sorry for my english.
Regards

 

[odlanor]

Rated voltage and lenght of transmission line:

 

[odlanor]

Rated voltage and lenght of transmission line??

 

[Tofeil]

Vrated=400 kV
Length= 300 km

 

[odlanor]

in my opinion should be Zc=√(L1/C1 , where L1 e and C1 are per phase.

 

[Tofeil]

therefor, why do you ask for rated voltage and length of transmission line?

 

[odlanor]

because characteristic impedance is defined in distributed line model.
This model is applied at lines with length >=250km . I see normally at long EHV transmission lines.