As many variables were unobservable, especially for crop growth status, so when solving optimal control problem of intelligent greenhouse, several difficulties appeared concerning the greenhouse and crop model, the criterion and the computation of the optimal controls. In order to evade modeling difficulty, one method was utilizing fuzzy logic and neural network technology that realize the models by the black box and gray box theory. In receding horizon optimal control, a finite horizon open-loop optimal control problem, with initial values based on actual measurements, was solved at each time step. The computation was repeated at the next time step, moving the horizon one step up. The simulation results are accord with the rule of plants growth. Studies on optimal control method of plant environment in greenhouse by means of soft compute technology have been developed. Nowadays, the greenhouse environment optimal control focus on energy saving, economic profit, environment protection and continually develop.
Published in:
Intelligent Control and Automation, 2004. WCICA 2004. Fifth World Congress on
(Volume:6
)
Date of Conference: 15-19 June 2004