Greenhouse temperature and humidity decoupling control method and system

Abstract

An embodiment of the invention provides a greenhouse temperature and humidity decoupling control method and system. The method comprises the following steps: establishing a greenhouse temperature andhumidity prediction model according to energy and matter conservation laws, outdoor climates influencing indoor states comprising outdoor solar radiation, outdoor temperature, outdoor wind speed and outdoor humidity, and indoor control input comprising heating and ventilation opening degree; converting the greenhouse temperature and humidity system prediction model into an affine non-linear system; carrying out accurate linearization on the affine non-linear system through coordinate transformation and nonlinear state feedback to obtain 2 independent integral and time delay systems; and designing a PID (proportional integral derivative) controller based on the equivalent integral and time delay systems, and obtaining opening degree of heating and ventilation two control devices to enable system state to effectively track a set value. The method and system consider strong coupling characteristic of greenhouse temperature and humidity in the control process.

Description

technical field [0001] The embodiments of the present invention relate to the technical field of greenhouse environment regulation, and in particular to a processing method for decoupling control of temperature, room temperature and humidity. Background technique [0002] The special structure of the greenhouse forms an internal microclimate environment that is relatively isolated from the external climate environment. The internal environment regulation directly affects the crop yield, quality and economic benefits of the entire production cycle. Greenhouse environmental factors are affected by outdoor measurable and uncontrollable disturbances and the input of control equipment, and have nonlinear and strong coupling characteristics. This characteristic increases the complexity of the model-based greenhouse environmental regulation algorithm design, and the control of each environmental factor is not Completely independent, the control loops are coupled to each other. [...

AI Technical Summary

Problems solved by technology

The switch control strategy does not take into account the greenhouse environment model, and the set point tracking effect is not ideal

The PID controller has a simple structure and is easy to implement, and is widely used in the design of controllers for greenhouse engineering applications. Overshoot occurs, and the control effect is poor

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