Energetic Approach for Control Surface Disconnection Fault Detection in Hydraulic Aircraft Actuators

This work proposes a new approach to detect the disconnected mechanical load in electro-hydraulically actuated control systems. The detector applies a Fault Model of the hydraulic actuator in which the load force is neglected. Instead of system output based analytical redundancy the model compares the energy intake of the real actuator and of the Fault Model. With this approach the disconnection between the load and the actuator can be detected, even when the difference between the real system output and Fault Model output is in order of the measurement noise. The proposed method is applicable for aircraft control surface disconnection detection with unmeasurable aerodynamic force.