Abstract:
It was an urgent issue for the waste of water resources caused by the traditional irrigation methods. In order to improve the utilization efficiency of water resources, based on the automatic control technology and wireless communication technology, a set of rice irrigation control system with wireless transmission was designed in this paper. There were eighteen portable data acquisition station which transmitted wirelessly. The station using the PIC18F4520 microcontroller could control the temperature, humidity and liquid level sensor by setting the interval of data acquisition time. ND250A digital radio was connected with microcontroller by RS232 serial port. The data information was sent to the master station via the radio station. The power supply module of base station was made up of the solar energy battery and voltage control circuit, which could output 5 V and 12 V DC voltage and guarantee all the equipment of the base station operating stably for a long time in the open air of field work. According to the cold environment in the area of the north and rice water requirement, the solar heating system on the basis of increasing water temperature by sunning naturally was introduced in this paper, which utilized the extensive solar collectors to heat exchange, and could output rapidly the suitable warm water for the growth of rice (25℃). This system controlled and managed the executive equipments such as the irrigation water pump and the electromagnetic valves by SLC500 programmable controller. Factorytalk View Configuration software was used to design the man-machine interface, control the information collection, analysis and process the data, monitor the operating conditions of the system, realize the remote automatic or manual control and control precisely irrigation water volume. There was a large number of HD camera distributing in and around the paddy fields, so the rice growth situation could achieve the real-time display by the video management software. What’s more, the growth conditions of rice plant could be viewed in detail by 30 times optical zoom lens. At the same time, it also monitored the irrigation system and the collection of the base station operation conditions. All the software control was concentrated in the control center which the industrial PC was communicated with PLC by OPC. The center set up the information management interface based on WEB and developed the data management system software with SQL dataset, which provided the comprehensive data analysis, report inquiry and type and trend display charts and other functions. Video server in the center was responsible for storing video data and provided the consult for users at any time. Since the system put into operation, it was timely for the information collection, stable for the wireless transmission, normal for the automatic irrigation system operation and clear for the data analysis results. So it met the design requirements of system, especially it was great significant for the automation irrigation of rice in the northern.