Solar Greenhouse Environmental Factor Monitoring And Thermal Insulation、risk Control System Development

With the development of modern facility agriculture,the traditional vegetable production management mode has not met the requirements of the times.As the main anti season vegetable planting facility in the north of China,the solar greenhouse has some problems,such as the backward monitoring equipment of environmental factors,the poor reliability of greenhouse thermal insulation and ventilation equipment,and the low degree of automation.In view of the above problems,this project developed a closed-loop control system for monitoring the environmental factors of solar greenhouse and for heat preservation and ventilation,which improved the automation degree and production efficiency of greenhouse management.The main research results of this project are as follows:(1)Based on STM32 and GPRS,a multi-point and multi factor monitoring system for crop growth environment in solar greenhouse was developed.In this system,the environmental factors such as air temperature and humidity,carbon dioxide concentration,light intensity and soil temperature and humidity inside and outside the greenhouse are monitored in real time in multi-point and sub region,and the two dimensions of horizontal and vertical direction are analyzed.The horizontal and vertical dimensions were analyzed,in which the horizontal direction was evenly divided into nine areas.In the vertical direction,the relevant environmental factors were analyzed in five levels: 0.2m,1m,1.5m,2m,2.5m from the ground surface and 0.1m,0.2m,0.3m from the underground.The multi-sensor data fusion algorithm is used to process the data and provide data and decision support for the regulation of greenhouse temperature,humidity,CO2 and other environmental factors.(2)Aiming at the low automation and poor reliability of film rolling machine and curtain rolling machine in solar greenhouse,a closed-loop control system of heat preservation and air release is developed.In the control strategy,the collected environmental elements are combined with traditional planting experience and fuzzy PID control algorithm to carry out intelligent control of heat preservation and air release equipment.The control of the roller shutter is mainly based on the factors such as the light intensity outside the greenhouse and the indoor temperature.The energy balance strategy is adopted to realize the automatic closed-loop control of the roller shutter when the night temperature is maintained at 9-12 ℃;The fuzzy PID algorithm is used to control the film rolling machine,to realize the automatic adjustment of the opening of the vent,to achieve the effect of cooling,dehumidification and increasing the concentration of carbon dioxide,which has a positive effect on reducing plant diseases and improving the yield.(3)In order to ensure the normal operation process and results of the rolling quilt,the paper monitors the running state of the rolling quilt by combining the limit switch and the multi-level travel switch.The maximum deviation threshold of the travel at both ends of the insulation quilt is set to 15 cm,and the maximum threshold of the number of continuous deviation is 5 times.In case of deviation beyond the set range,it will automatically adjust and feed back to the user;if the control result does not meet the requirements,it will notify the user through the alarm SMS.