TECHNICAL FIELD

The present disclosure relates generally to gas turbine engines, and more particularly to detecting and accommodating the loss of a torque signal on gas turbine engines.

BACKGROUND OF THE ART

Turboshaft and turboprop engines for aircraft use a torque signal for governing either on torque or on power. In the unlikely event that the torque signal is lost, it is desirable for engine control systems to be designed so that engine control is maintained. As such, there is a need for improvement.

SUMMARY

In accordance with a broad aspect, there is provided a method for operating a gas turbine engine. The method comprises obtaining, at a control system associated with the gas turbine engine, a measured engine core speed and an actual power demand for the gas turbine engine during operation thereof, determining an expected engine core speed based on the actual power demand from a predicted relationship between engine core speed and engine output power, comparing the measured engine core speed to the expected engine core speed, detecting a torque-related fault when the measured engine core speed differs from the expected engine core speed by more than a threshold; and accommodating the torque-related fault when detected.

In accordance with another broad aspect, there is provided system for operating a gas turbine engine, the system comprising a processing unit and a non-transitory computer-readable medium having stored thereon program instructions. The program instructions are executable by the processing unit for obtaining, at a control system associated with the gas turbine engine, a measured engine core speed and an actual power demand for the gas turbine engine during operation thereof, determining an expected engine core speed based on the actual power demand from a predicted relationship between engine core speed and engine output power, comparing the measured engine core speed to the expected engine core speed, detecting a torque-related fault when the measured engine core speed differs from the expected engine core speed by more than a threshold; and accommodating the torque-related fault when detected.

Features of the systems, devices, and methods described herein may be used in various combinations, in accordance with the embodiments described herein.

