The type implemented is the
PSS2A, described in the chapter 8.2 of the
same IEEE Std
421.5-1992.
Since the PSS has zeros in the origin applied to both inputs,
its output at steady-state is always zero. Hence, its
initialization at steady state is trivial and corresponds to zero
output.
.PowerGrids.Electrical.Controls.PowerSystemStabilizers.IEEE_PSS2A