Hydro generator model with governor and exciter.
Hydro turbine and generator-rotor, elastically coupled.
Steady-state initialisation:
If combined with 'Control.Setpoints.Set_w_p_v' or similar, the setpoint values p_set and v_set are determined at initialisation from initial active power and voltage. The corresponding value for the speed w_set is determined by the system frequency system.f0.