The harmonic balance method is extended to the steady-state analysis o
f power system models that include complex nonlinearities and variable
topology power electronics equipment as may be user-assembled from ba
sic EMTP-TACS components. In applying the harmonic balance method, the
se devices are considered as black boxes and isolated from the linear
part of the model. A shooting method is used to accelerate the computa
tion of their intermediate time-domain steady-state responses and to s
olve the harmonic balance equation formulated as a fixed point problem
. Numerical tests show that the resulting generalized harmonic balance
method is very promising for lightly damped dynamic power system mode
ls.