Abstract
It is pointed out that frequency dependent effects of some elements of transformation matrix of double circuits transmission line constructed by current eigen-vector formings contradict physical causal relationship. This contradiction may be a substantial factor of error for any expression of a transient program in modal frame.
This paper presents a technique to remove the contradiction and to stabilize the characteristics in low frequency by means of modification of line constant. The technique is effective for double circuits DC transmission lines with neutral lines and make the apporoximation process by low order transfer function simple.
Effect of the modification is included in equivalent circuits composed of integrated resistance accounted at low frequency and modified distributive line. The transient behaviour of the equivalent circuits are closely similar to these of Fourier tranformation.
