Wind Turbine High Wind Hysteresis Settings

The word 'hysteresis' refers to a lag in a system's response to changing conditions. It applies to the high wind cut-out behavior of a wind turbine because a turbine will typically shut down when the wind speed exceeds some high value like 25 m/s, but then it will not restart until the speed drops to some lower threshold such as 22 m/s.

Windographer's high wind hysteresis settings allow you to specify the wind speeds at which the turbine cuts out and then restarts. You can enter the cut-out and the restart speeds at multiple time scales. The screenshot below shows an example where the turbine will enter high wind shutdown when any of the following three conditions are met:

the 10-minute average speed exceeds 25 m/s,
the 30-second average speed exceeds 28 m/s, or
the 3-minute average speed exceeds 30 m/s.

The settings further stipulate that after shutting down for high winds, the turbine will not restart until both of the following conditions are met:

the 5-minute average speed drops below 22 m/s, and
the 100-second average speed drops below 24 m/s

You can enter the high wind hysteresis settings in the Edit Wind Turbine window, and in the Wind Turbine Output window you can indicate whether you want to apply them.