During operation of electric power systems, not only short-circuit modes can occur, but also breaks. The phase coordinate method allows you to simulate wire breakage.
In fig. 1 shows a circuit replacement circuit. At the point of wire breakage, a large active resistance is set (R = 1010 Ohms).
Fig. 1. Break equivalent circuit
In the phase coordinate method, the break is described by the direct transfer matrix
where 
, 
, 
.
Cliff modeling is performed using resistances RA, RB, RC. To simulate a break, for example, in phase A, the resistance is set equal to 1010 Ohms. Similarly model faults in other phases.
The attached file shows the calculation of the break matrix A in Matlab: файл A_break.m