THE OPTIMAL MANAGEMENT OF THE MICRO CLIMATE OF THE AGRICULTURAL GREENHOUSE THROUGH THE MODELING OF A FUZZY LOGIC CONTROLLER

Climate is an essential factor in the physiological activity of plants. The radiation is predominantly involved in photosynthesis and temperature, which largely determines their growth and development. Sweating plays a fundamental role in the movement of water and minerals in plants and it also greatly depends on the temperature and humidity of the air. Greenhouses are structures that make it possible to control the climatic environment so that plants are in a Environment, the latter requires an intelligent and precise control to achieve it and ensure optimal management. The management of micro climate in greenhouses is a certain skill, especially in the sunny regions (arid and semi-arid region). However, the analysis of the response of a greenhouse as a function of the external climatic conditions then makes it possible to better understand its operation. A more precise analysis of the mechanisms governing the exchange (heat and mass) between indoor air and the environment is therefore essential for improving irrigation, ventilation and heating systems and thus Better climate control under shelter. It is even possible to optimize the systems of fertilization, and spraying, thus the agro-greenhouse system in general. This problem concerns all the more the farmers (the serrists) and the manufacturers of greenhouse together; Since these mechanisms are limiting factors which have a strong influence on production both in terms of quantity and quality, it now appears that good management of the greenhouse microclimate can both improve crop preservation and reduce Costs incurred. The micro-climate management interface of the agricultural greenhouse takes into account sunshine, temperature, humidity level, external weather conditions such as rain, wind direction and wind speed. It intervenes alone according to the needs of the plant, but modifications can nevertheless be carried out remotely by the user by the sensor means and the actuators. Current systems in agricultural greenhouses follow logical rules according to a binary system: if the temperature exceeds a predefined threshold, the automaton is triggered to refresh or reheat the ambient air. What we are trying to develop is a control law that allows to optimize the growth of plants while reducing the energy costs. The system would maintain constant temperatures and humidity levels in the agricultural greenhouse, regardless of outdoor climatic conditions. And this is where the whole difficulty lies, the intelligent control by the fuzzy logic that governs a greenhouse can solve most of these problems and difficulties. This work of our paper includes the modeling of the agricultural greenhouse (real model), the modeling of a fuzzy controller and the simulation of the model using real data from a given site (Dar el Beida Algeria) The fuzzy logic of our control for climate variables and parameters of the agricultural greenhouse as well as for air conditioning, heating and ventilation systems. The use of real data is very important because it will allow us to validate our model and give meaning to the simulation and define the different gains and parameters of the controllers. At present, this attitude has evolved. It may be thought that the fuzzy command To take little place in the contemporary engineer's array, without supplanting traditional methods, and that it will be a valuable complement in the case of agricultural greenhouses which are equipped with systems that are difficult to identify or whose parameters undergo sudden variations.