Research On Photovoltaic Agricultural Greenhouse Based On Expert System

According to the dry weather condition and enough sunshine characteristics in northwest of China, solar photovoltaic technology is introduced into agricultural greenhouses system design of desert. This can not only solve the partial energy issue of the system, but also improve the land utilization. Using the strategy of intelligent water-saving irrigation of expert system to save water, while achieving the automation and intelligent of greenhouse. For the above characteristic in this paper, the research includes the following aspects:For field survey of traditional greenhouse in Zhongwei Ningxia, implementing modification of the greenhouse based on reality. In order to ensure the normal growth of crops under high temperature, opening the skylight on the top of the greenhouse, increasing fan and wet curtain of north and south respectively, laying irrigation pipes inside the greenhouse, and installing control solenoid valve, etc. Meanwhile analyzing the inside structure of greenhouse, and determining the layout for each sensor node in greenhouse.Configuration software construct the wireless sensor network by using Zigbee technology for sensor data acquisition and storage; and controls the status of all kinds of motor and solenoid valve of greenhouse via 485 bus. Using Modbus-RTU protocol to realize system monitoring and control.According to the demand analysis of the irrigation system and the inverter constant pressure irrigation system requirements, the system adopts the technology of frequency control of motor speed, this makes the pressure of irrigation pipe network maintain at a predetermined set range to realize the function of constant pressure water supply irrigation.Establishing expert system for irrigation through summarizing and collecting long-term accumulation valuable experience from agriculture experts, and all kinds of information has been obtained by the experimental data, thus realizing the automation and intelligent of irrigation system by configuring related parameters in irrigation strategy.Debug the system hardware and analysis the the relevant data, according the current environmental conditions in greenhouse make corresponding adjustments, such as control the normal operation of water cycle, irrigation time, each fan, skylight, wet curtain and the solenoid valve, etc.The system has been completed and after a long time operation, the results show that the design of the photovoltaic (pv) agricultural greenhouse of irrigation control system based on expert system can realize the expected functions, the system operation is stable, and playing an demonstrate role to the northwest agricultural development.