CAJ | 학술논문

以往的温室作物生长和小气候环境模型，主要是从面向研究而不是面向实际生产的温室获得的，这二者的最大不同是：面向研究的模型主要考虑的是得到作物生长高产所需的“最优”的温室内部气候环境参数设定值，而较少考虑温室内控制设备的能力（控制动态过程）、生产过程中温室外气候变化情况和达到“最优”所需付出的能量等代价；而后者在面向实际生产的自动化控制的温室系统模型中是必不可少的。当前温室系统自动化控制面临的一个最大困难，就是缺乏一个这样的可靠的温室系统模型，而只能采用面向研究的温室系统模型去进行实际生产的温室系统控制，这种忽视实际生产条件下的温室系统模型与理想条件下的模型之间差异的“纸上谈兵”的做法，必然导致温室控制技术水平低、达不到预期效果。该文介绍了温室系统的整个控制过程，对一个实际生产的温室系统中各种变量和参数作了简要描述，并概括了面向实际的温室生产控制要求的温室系统模型的基本结构，对温室环境模型、作物生长模型和能耗及CO 2消耗模型的研究现状作了详细的回顾。从满足控制需求出发对现有的温室系统模型所存在的问题进行了分析，并指出了其中的不足和局限性。探讨了未来温室系统的建模方法和需要解决的关键问题，提出了面向控制需求的温室系统建模要满足的要求，为温室系统的建模研究提供了一种新的思路和方向。
이왕적온실작물생장화소기후배경모형，주요시종면향연구이불시면향실제생산적온실획득적，저이자적최대불동시：면향연구적모형주요고필적시득도작물생장고산소수적“최우”적온실내부기후배경삼수설정치，이교소고필온실내공제설비적능력（공제동태과정）、생산과정중온실외기후변화정황화체도“최우”소수부출적능량등대개；이후자재면향실제생산적자동화공제적온실계통모형중시필불가소적。당전온실계통자동화공제면림적일개최대곤난，취시결핍일개저양적가고적온실계통모형，이지능채용면향연구적온실계통모형거진행실제생산적온실계통공제，저충홀시실제생산조건하적온실계통모형여이상조건하적모형지간차이적“지상담병”적주법，필연도치온실공제기술수평저、체불도예기효과。해문개소료온실계통적정개공제과정，대일개실제생산적온실계통중각충변량화삼수작료간요묘술，병개괄료면향실제적온실생산공제요구적온실계통모형적기본결구，대온실배경모형、작물생장모형화능모급CO 2소모모형적연구현상작료상세적회고。종만족공제수구출발대현유적온실계통모형소존재적문제진행료분석，병지출료기중적불족화국한성。탐토료미래온실계통적건모방법화수요해결적관건문제，제출료면향공제수구적온실계통건모요만족적요구，위온실계통적건모연구제공료일충신적사로화방향。
Economy-based optimal control of greenhouses is an important technique to reduce the operating cost and increase the crop yield. In General, the structure of a typical greenhouse control system consists of two layers:the objective optimization layer and the process control layer. The aim of the former is to obtain the target trajectories of environmental states; while in the latter, environmental states are tuned to track those obtained trajectories. Based on this framework, some relevant models to the greenhouse system, such as greenhouse microclimate model, crop growth and yield model, energy consumption predicting model and CO2 consumption predicting model, need to be built, and some constraints over environmental states and control inputs must be determined. However, most greenhouse climate models and crop growth models proposed in literature are research-oriented rather than based on practical cultivation. The biggest difference between the two is that research-oriented models solely focus on the optimal set-points of internal climatic parameters for maximum crop yield, ignoring the abilities of control actuators, the ambient climate change, and the overall energy consumption. From a practical point of view, the latters are certainly necessary in greenhouse models. It would be difficult to achieve realistic results if the models are incomplete. The lack of reliable greenhouse models has become the greatest difficulty for greenhouse optimization and control. In this paper, the latest trends in greenhouse climate models, crops growth models, energy consumption models, and CO2 consumption models are reviewed in details. The main shortcomings of current models can be summarized as follows:(1) although some models obtained by ample mechanisms, their structures are excessively complicated, such that the corresponding computations are very expensive, which makes it difficult to design an efficient controller based on them. This class of models interprets the real physical laws with large number of parameters and complex structures, and Vanthoor’s model and TOMGRO are examples; (2) some models are too simple to accurately reflect the relationships between greenhouse environment and crop growth. Generally, only the dynamics of air temperature and humidity in greenhouses are described in this class of greenhouse climate model, such as Albright’s model, while the dynamic of CO2 concentration, which is an important environmental factor to affect photosynthesis, is not included. Furthermore, the influence to crop growth of environmental factors is always partially reflected in simplified crop growth models, e.g. in radiation and thermal effectiveness model, only air temperature and radiation is used to describe the accumulation and allocation of dry matter;(3) only single control input variable is included in many greenhouse climate models, such as the thermal environmental model of solar greenhouse, this is because most greenhouses are not equipped with relevant control actuators. Generally, these greenhouse climate models are used to guide the structure design, material selection, or management of greenhouse production. Additionally, although some greenhouse climate models include various control inputs, including heating, fogging, ventilation and CO2 injection, the dynamic response of control actuators are still not described adequately, and so, they can’t be used for greenhouse climate control. In order to obtain a suite of efficient greenhouse models, great efforts need to be made to solve the following key problems: (1) the unknown mechanisms of some processes need to be explored further for a mathematical expression of their input-output relationship. Provided with these results, some complex models can be improved; (2) based on a complex model with detailed mechanistic expressions, some dynamic sub-processes can be reconstructed or simplified to reduce the model complexity; (3) new approaches and theories about system modeling and model validation can be developed.