Merging of lines..

[nilesh patel]

Dear Sir,      My power system to be simulated consist of 
three parallel lines having same length and all  parameters between two 
buses. (There are no. of such lines in parallel so system size increases to 
much).
My question is- Can i merge all parallel (three) lines as one line in 
simulation or all actual lines to be taken?
Thanking u. 
 
Nilesh Patel