|Genetic Algorithm for Identification of Time Delay Systems from Step Responses
Gang-Wook Shin, Young-Joo Song, Tae-Bong Lee, and Hong-Kyoo Choi
International Journal of Control, Automation, and Systems, vol. 5, no. 1, pp.79-85, 2007
Abstract : In this paper, a real-coded genetic algorithm is proposed for identification of time delay systems from step responses. FOPDT (First-Order Plus Dead-Time) and SOPDT (Second-Order Plus Dead-Time) systems, which are the most useful processes in this field, but are difficult for system identification because of a long dead-time problem and a model mismatch problem. Genetic algorithms have been successfully applied to a variety of complex optimization problems where other techniques have often failed. Thus, the modified crossover operator of a real-code genetic algorithm is proposed to effectively search the system parameters. The proposed method, using a real-coding genetic algorithm, shows better performance characteristics when compared to the usual area-based identification method and the directed identification method that uses step responses.
Keyword : Genetic algorithm, identification, step response, time delay system.