单慧勇 李晨阳 张程皓 赵辉 卫勇 郭旭存



摘要: 针对当前温室环境调控成本较高的问题,为了在满足作物生长需求的条件下降低调控成本,拟研究1种在有限二氧化碳(CO2)资源条件下的温室光气耦合优化调控模型。首先,以温度、CO2浓度、光照度作为输入,以净光合速率作为输出,构建基于最小二乘支持向量机(LS-SVM)的光合速率预测模型;然后,基于提出的光合速率预测模型,构建在有限CO2资源条件下温室CO2优化调控模型数据库,可根据用户输入的CO2资源总量,自动寻优获取最佳补气时间与单位补气量;最后,提出以光照度增长相对价值为评价指标的经济性相对最优的补光策略,在确定的补气时间段内进行补光,最终实现了有限CO2资源条件下的温室光气耦合优化调控,进一步提高了设施温室环境因子调控的精准度与智能化水平。
关键词: 光合速率预测;光气耦合;调控模型;最小二乘支持向量机(LS-SVM)
中图分类号: S24;S11+9 文献标识码: A 文章编号: 1000-4440(2021)02-0471-09
Abstract: Due to the high cost of environmental regulation in greenhouse, an optimal control model of greenhouse light gas coupling under limited carbon dioxide(CO2) resources is proposed to reduce the cost of regulation and control under the condition of meeting the needs of crop growth. Firstly, the photosynthetic rate prediction model based on least squares support vector machine(LS-SVM) was constructed with temperature, CO2 concentration and illumination as input and net photosynthetic rate as output. Secondly, based on the proposed photosynthetic rate prediction model, the database of greenhouse carbon dioxide optimal regulation model under limited carbon dioxide resources was constructed. The optimal replenishment time and unit replenishment amount could be obtained automatically according to the total amount of carbon dioxide resources input by users. Then, a relatively optimal light replenishment strategy with the relative value of light growth as the evaluation index was proposed, and light supplement was carried out in a certain period of time. Finally, the optimal control of greenhouse light gas coupling under limited carbon dioxide resources is realized, which further improves the accuracy and intelligence level of greenhouse environmental regulation.
Key words: photosynthetic rate prediction;coupling regulation of light and CO2;control model;least squares support vector machine(LS-SVM)
在植物的光合作用過程中,温度、光照、二氧化碳等均是影响光合速率的主要因素,对于反季节的温室栽培而言,光照、CO2浓度是限制植物生长的主要环境因子[1-2]。因此,以提高作物光合速率为目的建立植物的光气耦合优化调控模型,是设施温室智能调控系统的重要组成部分。
光气耦合优化调控模型的基础是光合速率预测模型,传统的预测模型存在拟合精度低等问题,近年来,研究者以光合作用的主要影响因子为变量进行光合速率预测模型研究[3-5],构建了不同的光合速率模型,极大改善了预测模型的适应性和准确度。……