作　　者： ;

机构地区： 华南农业大学电子工程学院

出　　处： 《排灌机械工程学报》 2020年第3期318-324,共7页

摘　　要： 为了提高液肥深施效率,设计了一种基于ZigBee的液肥变量深施系统.该系统采用远程电脑终端与STM32F103RET6控制器同步结合实现液肥输出监测与控制:监控液肥水位值的同时利用流量传感器采集当前流量值,并通过ZigBee无线通信协议传输数据;根据流量预设值,利用增量式PID算法动态调整变频器频率,最终使试验系统能够精确控制液肥流量输出.在试验系统的基础上,通过液肥深施试验以探讨施肥深度、变频器频率、注肥压力、系统用泵的回水开度等参数对流量精确控制的影响,并利用试验数据建立精准控制流量的数学模型.果园试验结果表明,液肥变量深施系统整机施肥精度最高可达99.52%,单次施肥的液肥损耗量最大值为0.22 L/min;在改变施肥深度的情况下,系统液肥输出流量的最大差值为0.15 L/min,变频器频率的最大差值为0.79 Hz.在改变回水开度的情况下,确定了试验中系统的最佳工作参数,即回水开度在40%时,系统工作最为稳定,流量输出误差小,液肥损耗量少. To improve the efficiency of liquid fertilizer application,a variable liquid fertilizer applicator for deep-fertilization based on ZigBee technology was elaborated.A host computer with remote control software and a STM32F103RET6 microcontroller were combined to measure and control the li-quid fertilizer output.Through the ZigBee wireless communication network,this system realized the collection of liquid flow information in real time using flow meter while monitoring the liquid level,and an incremental PID control algorithm was used to dynamically adjust the converter frequency for reaching the set liquid fertilizer flow accurately.In the meanwhile,the performance experiment in the field analyzed and compared how parameters like the fertilizer application depth,the converter frequency,the fertilization pressure and the opening degree of back-water valve influenced the accuracy and the stabi-lity of the liquid variable deep-fertilization control.On the basis of the test data,a precise flow control mathematical model was also established.As the result,the orchard experiments indicated:the applicator accuracy is able to reach 99.52%and the maximum liquid fertilizer consumption in each fertilization process is 0.22 L/min;with the fertilizer application depth changing,the maximum flow output difference is 0.15 L/min and the converter frequency difference is 0.79 Hz.When adjusting the opening degree of back-water valve to confirm the optimum working parameters,which means the valve opening degree is 40%,the system works the most stably while owns the minor flow output difference and the low liquid fertilizer consumption.

关 键 词： 液肥施肥系统 变量施肥 深施

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