西藏高寒农牧区温室温度调控系统研究

Study on Greenhouse Temperature Control System in Tibetan Agricultural and Pastoral Areas

为了解决西藏高寒农牧区冬季夜间温室气温过低、不能种植蔬菜的问题,研究了西藏高寒农牧区的自然环境条件,提出了适合的温控方式.通过对夜晚温室传热条件的简化,建立了温室夜晚传热的数学模型,并在此基础上分析了温室补温的需求.从最小能耗与补温效果最佳两个原则出发,提出了自适应温室设定值调整方案;以温室外环境温度扰动为依据,对温室内的设定温度进行预测,然后结合温室大滞后非线性的特点,利用史密斯预估控制实现冬季夜间对温室温度的有效调控.温室温度调控系统能够有效地将温室温度调控至蔬菜正常的生长范围内,保证了蔬菜正常生长.适用于西藏高寒农牧区具有良好保温性能的温室和对温室温度的调控,为冬季在藏北地区温室中种植蔬菜提供了保障.

In order to solve the problem that vegetable can not be cultivated in Tibet alpine pastoral areas due to low temperature at night,the natural environment conditions of Tibet farming pastoral area in winter were studied,and suitable greenhouse types were put forward.By simplifying the conditions of heat transfer in night greenhouse,the mathematical model of heat transfer in night greenhouse is put forward,and the requirement of temperature replenishment in greenhouse is analyzed.Based on the two principles of minimum energy consumption and best temperature replenishment effect,an adaptive adjustment process of greenhouse setting value is proposed.Based on the disturbance of the external temperature of the greenhouse,the setting temperature of the temperature chamber is predicted.Considering the nonlinear characteristics of large lag in greenhouse,the effective control of greenhouse temperature at night and winter is realized by using Smith predictive control method.The greenhouse temperature control system can effectively control the greenhouse temperature to the normal growth range of vegetables and ensure the normal growth of vegetables.The greenhouse has a good thermal insulation performance and a greenhouse temperature control system adapted to the alpine agricultural and pastoral areas in Tibet.Vegetables can be planted in greenhouses in northern Tibet in winter.