The Research Of Model Free Control System Of Microhabita In Greenhouse Environment

Facility agricultural is an agriculture of effective production which get rid of the dependence on natural environment. It provides relative controllable environment conditions and even the optimum environment conditions including temperature, humidity, sunshine, water and fertilizer etc by modern agricultural engineering and machinery technology.Greenhouse is an important component of the facility agriculture, The key of the standard measuring greenhouse performance is how greenhouse adjust plant growth which are affected by these factors such as temperature, humidity, carbon dioxide and light etc and the level automation which greenhouse can achieve. The high precision integrated control automation of crop growth experiment environmental factors has gradually become an important platform support for biotechnology research. Based on the main parameters of the crops growth environment, especially on the soil-air temperature and humidity, coupled system which is analyzed by fusion detection, the model free control method is presented to solve the real-time control problem of main factor of the coupling parameters system in this paper. According to the demand of process parameters of crop cultivation in the production environment, this method simulates the expert specification and model free control principle, the concrete design experimental research is provided for the experimental temperature and humidity coupling effect of environment. And it is significant of the main parameters monitoring methods coupling of temperature and humidity of small ecological environment. The main work is completed as follows:1.In this paper, the main parameters of crops growth environment, especially the coupled system of the soil-air temperature and humidity was analyzed by fusion detection. The main parameters monitoring methods of small ecological greenhouse environment were studied, the definition of soil equilibrium moisture content and analysis of the coupling characteristics was achieved so as to build up the coupled model of temperature and humidity of small ecological environment.2. According to process requirements of crop cultivation environment and simulate the expert specification and control principle, on basis of PWM the model free control strategy of temperature and humidity of small ecological environment was studied and proposed. The definition of curve fitting was given which used as the technical performance indicators of temperature and humidity control system.3. The hardware, software system design and experimental research were provided for the environment of coupling temperature and humidity. Program achieved the PWM model free complex control rules of temperature and humidity on small ecological environment.The model free control method was presented to solve the real-time control problem of main factor of the coupling parameters system. Taking tomato as an example, adopting system design and experimental analysis of coupling environment such as its temperature, humidity and SEM, The results showed that the proposed method SEMC control curve goodness of fit reached more than 0.8, it illustrated effectiveness of the method in this paper.