具备ID卡功能的变量施液态肥控制器的研究

发布时间：2018-08-27 11:31

【摘要】：变量施肥技术是农业实现可持续发展的必要措施,自其诞生到今,已受到广泛认可。经历了百余年的研究与发展,变量施肥技术日趋成熟。开展此项技术研发较早的国家,通过应用于农田生产,收获了显著的经济效益与社会效益。在我国,变量施肥作业目前仍未得到普及,面对化肥不合理使用导致农田生态环境的逐步恶化,科学、智能、因地制宜的施肥方式是解决问题的根本,因此具备变量施肥功能的控制器的研究具有重要意义。变量施肥控制器分适用于固体肥与液态肥两种,本文主要对变量施液态肥的控制器进行了深入的研究。分析变量施肥控制器的工作原理,依据技术要求,制定了以单片机为控制核心,电磁比例调节阀为执行机构的控制器设计方案,围绕方案展开深入的研究。论文首先对控制器的硬件进行了设计,确定系统组成,重点对控制板、通信模块以及驱动电路进行研究,并将ID卡功能应用于控制器中,自主研发并设计了ID卡及其阅读器,利用其权限性,可以完成施肥配方和配置参数的修改,同时还可以实现对作业数据的管理,提高了控制器的安全性与可靠性,以及提高了与上位机的通信效率,缓解了数据存储压力。其次,对控制器的软件进行了精心设计,利用控制板处理器的定时中断功能控制调节阀开、关时间,为满足与上位机的通信功能,编写了相应接口函数,制定了固定的数据格式,同时利用PC机在VB环境下开发了模拟上位机系统,可实现GPS信息与车速信息的读取并进行分析计算。针对电磁比例调节阀的控制算法,传统PID与积分分离PID的应用出现了严重超调及动态响应慢的现象,因为施肥系统压力的限制,施肥出现明显不稳定情况,针对这一现象,特对此进行深入分析,最终设计了具备滞回特性的积分分离PID。稳定了输出,缩短了调节时间,提高了控制精度。经过综合研究,最终研发并设计一款具备ID卡功能、可实现手/自动控制的适用于三种液态肥混合控制的变量施液态肥控制器。为了验证设计方案的可行性和变量施液态肥控制器的工作性能,对控制器进行了静态测试与农田作业试验。通过对试验结果的分析,最终证实本文研制的控制器控制精度较高、抗干扰能力强、工作稳定可靠、操作简单方便,满足变量施肥的技术要求。
[Abstract]:Variable rate fertilization technology is a necessary measure to realize sustainable development of agriculture. It has been widely recognized since its birth. After more than 100 years of research and development, variable rate fertilization technology is becoming more and more mature. Variable rate fertilization is still not popular. Facing the gradual deterioration of farmland ecological environment caused by unreasonable use of chemical fertilizers, scientific, intelligent and local fertilization methods are the fundamental to solve the problem. Therefore, it is important to study the controller with variable rate fertilization function. Two kinds of fertilizers, this paper mainly studies the controller of variable rate liquid fertilizer. The working principle of variable rate fertilizer controller is analyzed. According to the technical requirements, the design scheme of controller with single chip microcomputer as the control core and electromagnetic proportional control valve as the actuator is formulated. The scheme is studied in depth. Firstly, the controller is designed. The hardware of the system is designed, and the composition of the system is determined. The control board, communication module and driving circuit are studied in detail. The ID card is applied to the controller. The ID card and its reader are designed independently. By using its authority, the fertilizer formula and configuration parameters can be modified, and the operation data can be also realized. The management improves the security and reliability of the controller, improves the communication efficiency with the host computer and eases the pressure of data storage. Secondly, the software of the controller is carefully designed, and the timing interrupt function of the control board processor is used to control the opening and closing time of the regulating valve. The interface function, fixed data format and the analog upper computer system are developed by using PC in VB environment, which can read GPS information and speed information and analyze and calculate. Because of the pressure limitation of the fertilization system, the fertilization is obviously unstable. Aiming at this phenomenon, this paper makes a thorough analysis and designs an integral separation PID with hysteresis characteristics, which stabilizes the output, shortens the adjustment time and improves the control precision. In order to verify the feasibility of the design scheme and the working performance of the variable rate liquid fertilizer controller, the static test and field operation test of the controller are carried out. Through the analysis of the test results, the controller control developed in this paper is finally confirmed. High precision, strong anti-interference ability, stable and reliable work, simple and convenient operation, meet the technical requirements of variable rate fertilization.
【学位授予单位】：东北农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S224.2

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