US Patent 9982607 Shaft failure detection using passive control methods

A method for use in a turbine control system includes controlling fuel supply to a gas turbine engine at least in part using a fuel supply limit determined as a first function of a rotational speed of a shaft of the gas turbine engine. The method also includes obtaining a first value representative of a rotational speed of the shaft, and differentiating the first value within a processing unit. The processing unit determines an adjusted fuel supply limit as an adjusted function of the first value. The adjusted function is based on the first function and the differentiated first value. The method further includes controlling the fuel supply to the gas turbine engine at least in part using the adjusted fuel supply limit.