Power control methods

摘要

In an oscillating water column (OWC) assembly power may be generated based on a power reference ( P ref ) that is derived from an estimate of the available mechanical power in the air turbine (2) or a measured pressure drop (” p ) across the turbine. The power reference ( P ref ) is used to derive a power control torque reference M ref Po within a power controller (14). A speed controller (16) uses a comparison of a measured speed (É) of the generator (8) and a maximum speed limit (É max ) to derive a speed control torque reference M ref É . A selector function (22) selects whichever of the power control and speed control torque references M ref Po �¢ M ref É is the maximum at any time instant. The selected torque reference M ref É is input to an anti stall torque function (24) where it is selectively modified by applying a speed dependent gain that decreases with decreasing turbine speed, preferably so that the main torque reference (M ref ) is zero for a minimum speed limit.