| Shutter machine is the equipment which is necessary for the production of the sun greenhouse in the north of China.The control is mostly by farmers operating the motor switch to close the shutter operation,in order to achieve the effect of insulation and heat storage.Improper operation can easily lead rolling mantle over the volume in the retracting process,falling from the roof caused economic losses.The time node of the open / closed shed is mainly determined by the farmers’ planting experience and the idle time.It can not scientifically and reasonably combine the weather conditions and the temperature inside the greenhouse to carry out the relevant operation,which can not achieve the optimal lighting time and night temperature in the solar greenhouse.This paper aims at the practical application of the control of the production of solar greenhouse shutter,In order to achieve early control of the shutter,the short-term temperature prediction model in greenhouse was constructed by using the time series analysis algorithm of wavelet neural network.Using ZigBee wireless sensor technology to design the environmental monitoring and rolling machine control system,And using infrared limit control technology to effectively prevent the rolling machine over the volume,in order to extend the sunlight greenhouse light time and speed up the crop nutrient accumulation speed within the appropriate temperature range.The main content and conclusions of this article are as follows:(1)Put forward the overall design scheme of greenhouse shutter control system.According to the solar greenhouse shutter control needs to complete the overall structure of the system design,including temperature time series prediction model,control,monitoring node and control platform 4 parts.Analysis of ZigBee wireless sensor technology and limit switch technology used in the system.(2)Construction of establishing a temperature prediction timing analysis algorithm based on wavelet neural network model.By collecting 9 points temperature from greenhouse indoor and illumination from outdoor,extract the average temperature as a training sample,choose the topology structure of wavelet neural network for the 4-6-1,the average temperature sample is used as the input value for network training,by adjusting the weights of network variables and parameter values constantly,get the temperature prediction model and analysis the model error.(3)According to the monitoring node and the control node to achieve the functions of hardware and software design.The monitoring node is responsible for the data collection and transmission of the solar greenhouse.The control node is responsible for the receiving and uploading of the environmental factor data,controlling the mechanical and mechanical action of the screen,and installing the infra-red antijet switch on top of the ceiling to prevent the volume.Hardware design includes the control node power supply circuit,sensor circuit,limit switch,the core processor circuit,serial communication circuit,relay circuit design;Software design includes the design of monitoring node data collection,control node data receiving upload,relay control.(4)Using the industrial control panel as control platform,compile automatic control interface.In the interface to show the indoor temperature of solar greenhouse,history temperature,predict temperature,real-time temperature and outdoor lighting,convenient managers to supervise the greenhouse temperature records,and to provide automatic control,manual control,forced to stop 3 control modes.Embedded temperature sequence prediction model in the platform.In the background of the control platform using C language compiler model embedded procedures,temperature threshold judgment procedures and control instructions.(5)After completing the overall design of the system,testing the system performance.Deployment system in the base,through half a month trial run,Statistical analysis of the stability and response time of the control platform,monitoring node and control node,upper and lower limit switches.the control platform,monitoring and control nodes,upper and lower limit switch.This thesis test ZigBee wireless sensor network by using transmission efficiency of the packet loss rate indicators.Test the overall function of the system and summarize the control function of the system during commissioning.Tests show that this system can effectively control the greenhouse temperature,reduce the production of solar greenhouse input costs,which plays an important role in promoting the development of solar greenhouse intelligent control direction. |
