毕 业 设 计 (论 文)

专 业 班 级 学生姓名 学 号

课 题 基于MATLAB的三容水箱液位串级 控制系统的设计

基于MATLAB的三容水箱液位串级控制系统的设计

指导老师：孙虹

摘 要

液位是工业生产过程中重要的被控量之一，因而液位控制的研究具有很大的现实意义。水箱的液位控制对石油、冶金、化工等行业来说必不可少。本论文的目的是设计三容水箱液位串级控制系统，在设计中充分利用自动化仪表技术，计算机技术，自动控制技术，以实现对水箱液位的串级控制。首先对被控对象的模型进行分析，并采用实验建模法求取模型的传递函数。然后，根据被控对象模型和被控过程特性并加入PID调节器设计串级控制系统，采用动态仿真技术对控制系统的性能进行分析。同时，通过对实际控制的结果进行比较，验证了串级控制对提高系统性能的作用。随着计算机控制技术的迅速发展，组态技术开始得到重视与运用,它能够很好地解决传统工业控制软件存在的种种问题，使用户能根据控制对象和控制目的任意组态，完成最终的自动化控制工程。 关键词：液位，串级控制，PID调节器,系统仿真

Abstract

Liquid level is one of important controlled variables in industrial process, so research on it has great realistic significance.The purpose of this thesis is to design the liquid level's cascade control system of the three-tank.This design makes full use of the automatic indicator technique ﹑the computer technique﹑the communication technique and the automatic control technique in order to realize cascade control of water tank's liquid.First, I carry out the analysis of the controlled objects' model, and use the experimental method to calculate the transfer function of the model .Next, I design the cascade control system and use the dynamic simulation technique to analyze the capability of control system and design the cascade control system ，according to the model of controlled object and characteristic of controlled progress,jioning the modulator of PID.In the meantime,by comparing the control system functions,I validate the effects of cascade control system on accelerating system performance.As computer control technology develops at a high speed, configuration technology is regarded and used, which can solve so many problems of traditional industrial control software that users can configure at will to finish their automatic projects according to their object and goal.

Keywords：liquid level，cascade control ,PID modulator，system simulation.