Journal of Control and Systems Engineering
Journal of Control and Systems Engineering(JCSE)

System Identification and Control of Underdamped System Using Dual Input Describing Function
An online relay test is performed to obtain process model parameters of an underdamped system with delay. Measurements made on the limit cycle response curve are used to identify the system dynamics. It is difficult to obtain the required limit cycle data during load disturbance due to the asymmetric limit cycle. A Dual Input Describing Function (DIDF) is used to extract the limit cycle data with and without load disturbances. The effectiveness of the identification technique is tested in the presence of load disturbances. A proportional-integral-derivative (PID) controller is designed for the identified underdamped system using the direct synthesis method.
Keywords:Asymmetric Limit Cycle; Dual Input Describing Function; Measurement Noise; Relay
Author: Venkata Ramana Kasi,Somanath Majhi,Anup Kumar Gogoi


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