A quasi-stationary mode is usually not included within phasor domain method.
However under some special assumptions, such an approach is allowed which yields
enormous savings of simulation time.
The quasi-stationary mode shall be understood as a sequence of steady
states on the following condition: parameters (which would be constant at
steady-state analysis) may vary extraordinary slowly compared to the system's
dominant time constant T.
It is signalized by slow alterations of amplitudes and phases of the
sinusoidal quantities.
Usually, it is a good choise if the dynamic processes have time constants
higher than 10*T.
Attention!!!
Please note for the present release that there is no algorithm implemented to test
if variations of parameters are slow enough. Hence, this is still a task to be
done by user.