摘要水箱水位的自动化控制是对于传统技术的一大革新，其智能化的特点极大改善了生产效能以及在相应环境下的工作成本。同时，准确的操作响应也减少了以往这一领域中水资源的消耗。

本次设计的主要体现是基于PLC水箱水位控制系统的分析与设计。在本次设计中，选用了西门子S7—200型可编程逻辑控制器、KYB型压力传感器、微型隔膜水泵等实现了水箱水位的自动化控制。该系统在工作模式下，不同水位通过压力传感器，将压力信号所对应的电流信号传递至PLC工作机，由PLC工作机输出控制信号至水泵，实现水箱水位的控制。86189

本文以THBDY-1单容水箱作为研究对象，基于恒定水位的控制目标，设计了单容水箱水位的自动控制系统。以西门子S7—200型可编程逻辑控制器为基础，建立了一套完善的控制系统，并通过水塔水位虚拟控制台验证了控制方案的可行性。针对单容水箱及其水位变化的规律，选型了EM235型扩展模块并引用PID算法，并将PLC程序固化于可编程逻辑控制器的存储模块中，实现了单容水箱水位实物控制。通过试验，该装置可实现水箱水位的恒定控制。

毕业论文关键词：PLC（可编程逻辑控制器）；水箱水位；传感器；水泵。

ABSTRACT Automatic control of water level of water tank is a major innovation of traditional technology, the characteristics of its intelligence has greatly improved the production efficiency and the cost of work in the corresponding environment。 At the same time, accurate operation response also reduces the consumption of water resources in the field in the past。 

The main embodiment of this design is based on the analysis and design of PLC water tank level control system。 In this design, the use of the SIEMENS S7 - 200 programmable logic controller, KYB pressure sensor, water pump and so on to achieve the automatic control of water level。 The system in the mode of operation, relying on the pressure sensor, water in the water by different water levels corresponding induced currents of different obtained more accurate water level signal, by PLC machine output signal to the water pump, water tank level control。 

In this paper, the automatic control system of water level of single tank is designed based on the THBDY-1 single tank water tank as the research object and the control target of constant water level is designed。 Based on Siemens S7 - 200 type can be programmable logic controller based on established a perfect control system, and demonstrate the feasibility of the control scheme by the water tower water level virtual console。 EM235 for single capacity water tank and the water level changes in the rules, the selection of the expansion module and reference the PID algorithm and PLC program can be solidified in programmable logic controller storage module, the realization of the single capacity water tank water level physical control。 Through the test, the device can realize the constant control of the water level of the water tank。 

KEYWORD：Programmable Logic Controller; water level of the tank; pressure sensor; water pump。

目  录

第一章 绪论 1

1。1  研究目的与意义 1

1。2 研究现状与趋势 2

1。3 主要研究内容 3

第二章  控制设备的工作原理 4

2。1 S7-200型可编程逻辑控制器工作原理 4

2。2 S7—200的组成 4

    2。2。1 S7—200的基本单元 4