Speed avoidance logic for a variable speed wind turbine

Abstract From the Canadian patent

Speed Advoidance Logic For A Variable Speed Wind Turbine, A variable speed wind turbine is controlled in a way which avoids the turbine lingering at a critical speed which would otherwise tend to cause excessive vibration. The disclosed method and apparatus increases speed at a selected rate with respect to generator output power except in the vicinity of the critical speed. The selected rate is changed in the vicinity of the critical speed to a different rate which is selected slower in the selected embodiment to avoid commanding the critical speed. After the output power increases or decreases beyond the critical point, a deliberate discontinuity in the speed command signal is induced. A …