
152 Power System Transients
rise in the sending end voltage. The modal velocity for modes 2, 4, and 5 is esti-
mated at about 299.2 m/μs, and that of mode 1 is estimated at about 298.4 m/μs
at 1 kHz from Figure 1.26. The difference is the 1.8-μs delay in the arrival time
of mode-1 wave from those of modes 2, 4, and 5. This delay is the cause of the
“stair case” rise in the sending end voltage observed in Figure 2.8b.
Figure 2.8c shows the receiving end voltages when the source voltage is
applied to phase c. On phases a′ and b′, a voltage spike is observed just after
the arrival of the fastest traveling wave. This phenomenon is the same as
tha