重庆邮电大学移通学院本科毕业设计(论文)
重庆邮电大学移通学院
毕业设计任务书(简明)技术资料
一、设计题目:
题目18 随动系统的二阶参考模型串联校正设计及仿真研究
二、系统说明:
设二阶系统结构框图如所示
C2 R0 A R2 r R0 Rc Rf A R0 C1 y A 二阶系统结构框图
定义Gp?s?y?s???s?为原二阶系统开环传递函数。
其中:??s?r?s??y?s?
三、系统参量:
系统输入信号:r?t?;系统输出信号:y?t?;
四、设计指标:
1.设定:在输入为r?t??a?bt ,(其中:a?5 b?1/sec.);
2.在保证静态指标的ess?0.8 的前提下,要求动态期望指标:ts?2s(?%?5%)。
五、设计要求:
基于频率特性法,试用二阶参考模型法(即??22)设计串联校正装置,以使系统满
足设计指标的要求。
重庆邮电大学移通学院:自动化系 指导教师:汪纪锋
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重庆邮电大学移通学院本科毕业设计(论文)
日期:2014.12
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重庆邮电大学移通学院本科毕业设计(论文)
摘 要
在科技高速发展的今天,自动控制技术不仅在工业控制中有广泛的应用,而且在军事、农业、航空、航海、核能利用等领域也起着十分重要的作用。对于一个系统,首要的要求就是系统的稳定性。同时还要求系统的动态性能和稳态性能要满足实际要求,这些都可以通过设计校正来实现,使其达到期望的性能指标。
在本文中将要讨论的系统是典型的Ⅰ型2阶线性系统,首先使用劳斯判据判断系统的稳定性,再研究它的静态性能,动态性能是否达到要求。从系统分析中可以看出,在同时满足静态性能指标和系统稳定的前提下,无法通过改变放大倍数来使系统的动态性能满足。只有通过串联一个校正装置,才能使系统可以实现给定的性能指标,从而达到系统的设计要求。
本文对原系统采用二阶参考模型串联校正的方法来改善系统的性能指标,主要有以下这些步骤。第一步,做出原系统的固有特性图。第二步,依照性能要求,确定截止频率?c,作二阶参考模型特性。第三步,两线相减,求得校正装置。第四步,设置校正装置,作校正后的波德图,判断校正后系统的性能指标。
最后使系统在输入为r(t)?5?t时的静态指标ess?0.8,同时使动态期望指标ts?2s。并且用MATLAB对原系统和校正后的系统分别进行仿真,对比它们的波德图以及在指定输入下的输出,分析其是否达到要求。
【关键词】二阶 校正 仿真 线性
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重庆邮电大学移通学院本科毕业设计(论文)
ABSTRACT
In the rapid development of technology today, automatic control technology is not only widely used in industrial control, but also in the fields of military, agriculture, aviation, marine, nuclear energy also plays an important role. For a system, the first requirement is that the system stability. At the same time also requires the system dynamic performance and steady-state performance to meet the practical requirements, all of these can be achieved through the design of correction, enables it to achieve the desired performance.
The system will be discussed in this paper is a type of typical 2 order linear system, firstly the Routh criterion to determine the stability of the system, and then study its static performance, dynamic performance and can meet the requirements. From the system analysis can be seen, in the premise of static performance and the system stability and meet the dynamic performance, to meet the system could not be amplified by multiple to change. Only through the series a correction device, in order to make the system can achieve the given performance index, so as to achieve the design requirements of the system.
Performance index of the system by using two order reference model series correction method to improve the system, mainly has the following these steps. First, make the inherent characteristics of the original system diagram. The second step, according to performance requirements, determine the cut-off frequency, the two order reference model. The third step, the two lines subtraction, and seek correction device. The fourth step is to set the correction means, as corrected Bode plot, determine performance after correction system.
Finally, make the system static index less than or equal to 0.8 while enabling dynamic expectations index less than or equal to 2 sec when the input for r(t)?5?t. And the original system using MATLAB and corrected system simulation respectively, compared to their Bode plots and output in the specified input, the analysis of whether to meet the requirements.
【Key words】Second order Correction Simulation Linear
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重庆邮电大学移通学院本科毕业设计(论文)
目 录
前 言 .................................................................................................................................................. 1 第一章 自动控制系统概述 .............................................................................................................. 3 第一节 线性控制系统 .................................................................................................................. 3 第二节 自动控制系统的性能指标 .............................................................................................. 3 第三节 系统简述 .......................................................................................................................... 4 一、系统说明 ............................................................................................................................... 4 二、系统环节介绍 ....................................................................................................................... 4 第四节 设计指标 .......................................................................................................................... 5 第五节 本章小结 .......................................................................................................................... 5 第二章 系统建模 .............................................................................................................................. 6 第一节 各环节模型建立 .............................................................................................................. 6 一、比较器 ................................................................................................................................... 6 二、比例环节 ............................................................................................................................... 6 三、积分环节 ............................................................................................................................... 7 四、惯性环节 ............................................................................................................................... 7 五、反馈环节 ............................................................................................................................... 7 第二节 系统数学模型 .................................................................................................................. 8 一、系统结构框图 ....................................................................................................................... 8 二、系统传递函数 ....................................................................................................................... 8 三、系统等价框图 ....................................................................................................................... 8 第三章 系统分析 ............................................................................................................................ 10 第一节 稳定性分析 .................................................................................................................... 11 一、Nyquist稳定判据 ............................................................................................................... 11 二、劳斯稳定判据 ..................................................................................................................... 12 三、根轨迹的映证 ..................................................................................................................... 14 第二节 静态(精度)误差分析 ................................................................................................ 15
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