System Identification and Control of Environment inside Greenhouse

本研究采用系统辨识的方法对温室内的热环境进行了分析，并对系统辨识的适用性进行了探讨。此外，作为温室内热环境的控制系统，设计了基于OVSERVER的最优调节器，并对其控制性能进行了考察。首先，利用MA模型(移动平均模型)和ARMA模型(自回归移动平均模型)分析了具有外部辐射输入和室内空气温度输出的系统。研究了系统辨识的阶数与误差之间的关系。进行了基于外界辐射和风机开关确定室内空气温度的系统辨识，并在乙烯基模型温室内进行了水-空气换热器采暖/降温的室内热环境控制实验。观测器由ARMA模型的估计参数计算。基于Riccati方程的解和状态反馈增益，设计了最优调节器。通过实验考察了LQ控制(线性二次控制)中加权因子的取值对控制性能的影响。

In this study, the author analyzed the thermal environment inside greenhouse by means of system identification and investigated the applicability of system identification. Furthermore, as control system for the thermal environment inside greenhouse, optimal regulator with ovserver was disigned and control performance was examined.The experiment of system identification was carried out in a vinyl house. At first, the author analyzed a system with an input of outside radiation and an output of inside air temperature by means of MA model (moving average model) and ARMA model (auto-regressive moving average model). Relationship between order and error in identification of the system was also investigated. Identification of system which determines inside air temperature based on outside radiation and on-off of ventilating fan was also carried out.The experiment of control of the thermal environment inside greenhouse was carried out in a vinyl model greenhouse with a water-to-air heat exchanger for heating/cooling. Observer was calculated by the estimated parameters of ARMA model. Optimal regulator was designed based on solution of Riccati equiation and state feedback gain. Control performance was examined experimentally with some values of weighting factor in LQ control (linear quadratic control).