Controle de temperatura de estufas utilizando método de controle supervisório

Abstract

Greenhouses are structures used to set ideal environmental conditions for plant development. They are easy to build and maintain and vary in shape, structural components and other factors. They are made to adjust according to the needs of those who implent them, to a giving group of plants. One of the main factors that influence plant growth is the temperature inside the greenhouse. In order to reach the ideal temperature conditions for each group of plants automatically, a temperature control system, which models the actuators of a greenhouse environment and the events that occur in it, was developed. The validation of this control system was made possible thanks to the creation of a simulator developed according to the principles of mass and energy balance. The communication between the two entities takes place through a REST application interface. Three modeling proposals and rules for the control system are presented in this work. The main objective is to determine which one has the best feasibility and efficiency ratio in controlling the temperature inside the greenhouse, considering energy consumption, error rate in ºC and the percentage of time that the environment remains within ideal conditions. All proposals are based on the control of the states of two specific actuators in a greenhouse: the heating and cooling systems. The simulated scenarios use specific configurations for the greenhouse and a small tomato crop, in 24 hours periods for days chosen from different seasons. The control models showed different levels of efficiency, with up to 33% disparity.