自动控制原理课程设计报告.docVIP

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成绩

摘要

本设计通过对开环传递函数的串联滞后校正，改善了系统的各项性能指标，使校正后的剪切频率和相角裕度满足题目所给要求，并通过MATLAB编程给出了校正前和校正后的Bode图，Nyquist曲线，以及各个频域响应曲线。运用Nyquist稳定判据和对数频率稳定判据成功判出校正前和校正后系统的稳定性。

关键字：滞后，Bode图，稳定性，校正

目录

HYPERLINK设计题目···························································4

HYPERLINK一．概述·························································4

1.1设计题目··················································4

1.2设计目的··················································4

1.3设计要求·················································4

二．串联滞后校正的设计··········································4

2.1校正前的性能指标··········································4

2.2设计滞后校正··············································5

2.3校验······················································6

三.判断系统稳定性···············································7

3.1利用MATLAB求校正前与校正后的特征根·······················7

3.2校正前与校正后的动态性能··································7

3.绘制根轨迹·················································13

3.4绘制Nyquist曲线并判断稳定性·····························15

3.5根据Bode图判断系统稳定性·································16

3.6绘制校正前后幅相特性曲线·································16

HYPERLINK课程设计体会······················································18

HYPERLINK参考文献··························································18

概述：

1.1设计条件：

已知单位负反馈系统的开环传递函数试用频率法设计串联滞后校正装置，使

（1）校正后系统的静态误差系数

（2）相位裕度，

（3）截止频率为。

2.2设计目的

a.了解控制系统设计的一般方法、步骤。

b.掌握对系统进行稳定性分析、稳态误差分析以及动态特性分析的方法。

c.掌握利用MATLAB对控制理论内容进行分析和研究的技能。

d.提高分析问题解决问题的能力。

3.3设计要求

(1)、能用MATLAB解复杂的自动控制理论题目。

(2)、能用MATLAB设计控制系统以满足具体的性能指标。

(3)、能灵活应用MATLAB的CONTROLSYSTEM工具箱和SIMULINK仿真软件，分析系统的性能

二、串联滞后校正的设计

本设计使用串联滞后校正来改善系统的各项性能指标。串联滞后校正的基本原理，是利用滞后网络的高频幅值衰减特性，使已校正系统截止频率下降，从而使系统获得足够的相角裕度。因此，滞后网络的最大滞后角应力求避免发生在系统截止频率附近。在系统响应速度要求不高而抑制噪声电平性能要求较高的情况下，可考虑采用串联滞后校正，同时保持其动态性能仍然满足性能指标要求。?

2.1校正前的性能指标

校正前系统的开环传递函数为Ⅰ型系统，num=[0,25];den=[0.02,0.3,1,0];G=tf(num,den)

Transferfunction:

25

0.02s^3+0.3s^2+s

上图为未校正系统的bode图。

由上图可知：

幅值裕度Gm1=-4.44，相角裕度Pm1=-13

剪切频率Wc