Greenhouse Control Of The Environmental Parameter

In order to reduce the manpower material resources of agricultural facilities, theintelligent control technology of the greenhouse canopy has been rapidly development.Both developed countries and developing countries attach great importance to agriculturalfacilities. According to China’s regional characteristics of the greenhouse environmentconditions this thesis mainly research crops growth environment parameter controlproblems. This thesis mainly can be listed by the following several parts: the first partmainly make plenty of experimental data and mathematical methods establish mechanismmodel of greenhouse. Based on the principle of heat balance in greenhouse, mass balanceprinciple and carbon mass balance principle of greenhouse, this thesis describes themodeling process for the environmental parameters of the greenhouse; taking cucumbergrowth the environmental parameter as an example, the second part is mainly thecucumber growth data statistics and analysis based on cucumber plant experience whichmany researchers have summarized in early days so that this thesis concluded what thegrowth of cucumber optimal environmental parameter target curve is; to have establishedthe mathematical model of greenhouse canopy mechanism characteristics, such asnonlinearity, temperature and humidity in a greenhouse strong coupling, big delay,hysteresis and a series of complicated problem, the method which we used is mainlyapplied nonlinear control theory of input/output accurate state feedback linearizationmethod and progressive tracking method to design the controller and processing. Thetheory is mainly judgment of nonlinear decoupling matrix reversibility. Based on themathematical model of greenhouse canopy, the last part have pointed out simulationprogram and image of control algorithm. From the result of simulation, on account ofmechanism nonlinear input/output state feedback linearization control algorithm andincremental tracking controller in the greenhouse of canopy model satisfies some controlindex demand. It can be used as a control algorithm is applied to practice.The algorithm greatly depends on accuracy of the greenhouse canopy systemmechanism model, because this thesis proposed control algorithm is mathematicalprecision control. For this problem that control algorithm greatly depends on systemmechanism model, we need to be improved and enhanced place in the future.