一种经济型水肥一体化系统的设计

Design of an Economic Water and Fertilizer Integration System

我国作为农业大国,农业用水量巨大,占总用水量的70%,传统农业漫灌模式造成了大量不必要的水资源浪费。实施水肥一体化技术是减少农业用水浪费的重要举措之一。采用恒压供水、多级过滤器、多通道比例施肥机和无线网关等设备,辅以电导率(EC)、酸碱度(pH)、田间土壤墒情等土壤传感器,结合远程控制等技术,设计一种经济型水肥一体化系统。该系统在计算施肥比例时,施肥量可根据主管水流量而变化,同时利用压力变送器测量肥桶液位高度间接得到施肥量,通过增量PID算法减少肥桶液位波动产生的误差,实现精准施肥。试验结果表明,该系统能保证出水器的平均出水量不小于3.85 L/h,10 s采样周期的注肥量和设定值相比误差不超过10%,手机远程控制系统响应时间不超过3 s,达到生产要求的同时节水节肥。

China has relative scarcity of water resources,but as a agricultural power,it needs large amount of water in agriculture,accounting for 70%of total water consumption,which causes a lot of unnecessary waste of water resources under the traditional diffuse irrigation mode of agriculture.Implementing integrated water and fertilizer technology is one of the important measures to reduce the waste of water in agriculture.An economical integrated water and fertilizer system was designed combined with remote control technology,with equipment such as constant pressure water supply,multi-stage filter,multi-channel proportional fertilization machine and wireless gateway,supplemented by electrical conductivity(EC),pH,soil moisture in the field and other soil sensors.When calculating the fertilization ratio,the amount of fertilizer applied to the system varies according to the flow of water in charge.Meanwhile,it measures the liquid level height of fat barrel,the amount of fertilizer applied indirectly with pressure transmitter,realizing accurate fertilization by reducing the error of liquid level fluctuation in fat barrel with incremental PID algorithm.Finally,the system was tested.The result showed that the system can ensure that the average water output of the outlet was not less than 3.85 L/h,the error between the fertilizer injection for 10 s and the set value was not more than 10%,and the response time of the mobile phone remote control system was not more than 3s,which met the production requirements,as well as save water and fertilizer.