Identification methods of control objects using industrial controllers
Abstract
Identification methods of control objects using industrial controllers
Incoming article date: 20.03.2019The task of real-time identification of control objects is relevant and in demand at the stages of auto-tuning and self-tuning of regulators. Modern industrial controllers have sufficient computational capabilities to implement adaptive control. The article discusses two approaches to obtaining the impulse transfer function of an object: by the least squares method and directly by the transient response. Least square identification is applicable for a wide class of objects, including oscillatory objects. But this method requires a fairly large amount of computational resources, which imposes a limitation on the speed of the object. The direct identification method for transient response requires significantly less computational resources, but is applicable for aperiodic objects. Algorithms are implemented in the form of programs for industrial controllers and can be used both at the stages of preliminary identification of control objects and at the stages of autotuning typical PID controllers and controllers in the state space.
Keywords: adaptive control, pulse transfer function, least squares method, transient response, PID controller, programmable logic controller, state variables control, programming language ST, prorgamming language C, CoDeSys