Fault Detection in a Control Loop

Abstract This paper deals with a fault detection method applied to a control loop containing a non-linear actuator. In order to detect failures on the actuator, the sensor or the process itself, only three variables are available : the set-point, the measurement and the controller output. With the use of a static and a dynamical model of the system it is nevertheless possible to detect failures. To improve the quality of detection, a fuzzy C-mean algorithm is proposed to calculate the model parameters. The proposed method has been applied to a flow control loop containing a pneumatic valve.