The system described above was simulated using Matlab-
Simulink TM environment. A pseudorandom wind speed profile
was built; thus the input to the systems was a series of steps,
each one of same duration of 10 seconds. Although real wind
does not occur with such abrupt slopes, a series of steps is a
standard testing signal which permits a clear interpretation of
the system behavior. Fig. 6 shows the considered power versus
speed characteristic of the wind turbine for a wind speed
variation of 6.1 m/s, 6.7 m/s, 7.5 m/s, 8.1 m/s and 8.5 m/s. It
can be found that for each wind speed (Fig. 7a), Fig. 7b shows
that the expected furling dynamics of the wind turbine rotor
reached a stable state (within 10 seconds) and the furling angle