ME369-系统模型、分析与控制 4.2方块图 School of Mechanical Engineering ME369-Lecture 4.2 Shanghai Jiao Tong University Fall 2015 方块图定义 Desired value Actual value 结构方块图 设定值输入量 Controller Plant 实际值输出量 (Construction 控制对象 修 控制器 Block diagram) Feedback value measurer 反馈值 测量元件 依据信号的流向，将各元件的方块连接起来的图形化表达 R(s) E(s) C(s) G(s) 函数方块图 (Function Block diagram) B(s) H(s) School of Mechanical Engineering ME369-Lecture 4.2 Shanghai Jiao Tong University Fall 2015 1
1 ME369-Lecture 4.2 Fall 2015 School of Mechanical Engineering Shanghai Jiao Tong University 4.2 方块图 ME 369– 系统模型、分析与控制 ME369-Lecture 4.2 Fall 2015 School of Mechanical Engineering Shanghai Jiao Tong University 结构方块图 （Construction Block diagram） 依据信号的流向 ，将各元件的方块连接起来的图形化表达 方块图定义 Desired value 设定值/输入量 Controller 控制器 Plant 控制对象 measurer 测量元件 Actual value 实际值/输出量 Feedback value 反馈值 函数方块图 （Function Block diagram）
方块图定义（续） 1)只能沿箭头方向传递 2)用信号表达，时域或s域(t domain or s domain) Functional operation 函数运算功能 output inputG(s) Signal Function block 信号线 函数方框 U,(s) U(s) I(s) U(s) Summing point branch pint 求和点 引出点 Forward path Feedback path 前向通道 反馈通道 School of Mechanical Engineering ME369-Lecture 4.2 Shanghai Jiao Tong University Fall 2015 方块图定义一求和点（续） 求和点（比较点、综合点） X(s) X1(s)±X,(s) "summing":adder/subtractor Plus-minus operation of signals 信号之间代数加减运算的图解 X,(s) Algebraic operation rules of exchange, A+C-8 association,distribution 代数运算的交换律、结合律、分配律 B A+C-B 4=B A-B+C School of Mechanical Engineering ME369-Lecture 4.2 Shanghai Jiao Tong University Fall 2015 2
2 ME369-Lecture 4.2 Fall 2015 School of Mechanical Engineering Shanghai Jiao Tong University Summing point 求和点 Function block 函数方框 branch pint 引出点 Signal 信号线 1)只能沿箭头方向传递 2)用信号表达，时域或s域 ( t domain or s domain) Functional operation 函数运算功能 output input G s ( ) Forward path 前向通道 Feedback path 反馈通道 方块图定义（续） ME369-Lecture 4.2 Fall 2015 School of Mechanical Engineering Shanghai Jiao Tong University 求和点（比较点、综合点） Plus-minus operation of signals 信号之间代数加减运算的图解 Algebraic operation rules of exchange， association， distribution 代数运算的交换律、结合律、分配律 “summing” ：adder/ subtractor 方块图定义—求和点（续）
[例1]绘制方块图 u Ri+uo %=油 LT U,(s)=RI(s)+U(s) U.s)=11s) Cs School of Mechanical Engineering ME369-Lecture 4.2 Shanghai Jiao Tong University Fall 2015 例2]绘制方块图 ●● dx0=f0-f。-f 1 M X(s)=- d F()5()-F( 方=B「4@_40l F(s)=Bs[X (s)-X(s)] dt」 LT f人=K[x0-x E(5)=K[X(s)-X2(s)] M. (D=f+fe-f 1 X,(s)= dr 5(+5()-5 Ik:=K2x2(t) Fk,(s)=K2X2(s) School of Mechanical Engineering ME369-Lecture 4.2 Shanghai Jiao Tong University Fall 2015 3
3 ME369-Lecture 4.2 Fall 2015 School of Mechanical Engineering Shanghai Jiao Tong University [例1]绘制方块图 i 0 u Ri u 0 1 u i t d C LT ( ) ( ) ( ) U s RI s U s i o 1 ( ) ( ) c I s U s C s ME369-Lecture 4.2 Fall 2015 School of Mechanical Engineering Shanghai Jiao Tong University 1 2 1 1 2 ( ) ( ) B K d x t M f t f f dt 1 2 ( ) ( ) B dx t dx t f B dt dt 1 1 1 2 ( ) ( ) K f K x t x t 1 2 2 2 2 2 ( ) B K K d x t M f f f dt 2 2 2 ( ) K f K x t 1 1 2 1 1 ( ) [ ( ) ( ) ( )] X s F s F s F s B K M s 1 2 ( ) [ ( ) ( )] F s Bs X s X s B 1 1 1 2 ( ) [ ( ) ( )] F s K X s X s K 1 2 2 2 2 1 ( ) [ ( ) ( ) ( )] X s F s F s F s B K K M s 2 2 2 ( ) ( ) F s K X s K LT [例2]绘制方块图
[例2]绘制方块图（续） X(S)= MF)-F)-Fs】 F(S)=K[X(s)-X(S】 F(S)=Bs[X(s)-X,(S】 Fg(s) 1X(s) K X,(s) Bs r.e F(s) Fx(s) Fs(s) M,s- X,(s) F(s) X2(S)= ()+5(-5() 1 F,(s)=K2X2(S) School of Mechanical Engineering ME369-Lecture 4.2 Shanghai Jiao Tong University Fall 2015 例2]绘制方块图（续） F(3) □型 xK F() Fe (s) Fx (s) F,(9 ( Er(s) F(s) X;(s) F(s) Bs F,() F 口g Bs F.( M F:(s) School of Mechanical Engineering ME369-Lecture 4.2 Shanghai Jiao Tong University Fall 2015 4
4 ME369-Lecture 4.2 Fall 2015 School of Mechanical Engineering Shanghai Jiao Tong University 1 1 2 1 1 ( ) [ ( ) ( ) ( )] X s F s F s F s B K M s 1 2 ( ) [ ( ) ( )] F s Bs X s X s B 1 1 1 2 ( ) [ ( ) ( )] F s K X s X s K 1 2 2 2 2 1 ( ) [ ( ) ( ) ( )] X s F s F s F s B K K M s 2 2 2 ( ) ( ) F s K X s K [例2]绘制方块图（续） ME369-Lecture 4.2 Fall 2015 School of Mechanical Engineering Shanghai Jiao Tong University [例2]绘制方块图（续）
[例3]绘制方块图 i 4 C u,0-4@=i0 U,(s)-U,(5)=I(s) R R 40-2c0-0池 LT )=4- Cs 4①-.@=i,(0 Us)-U@=1,s) R E ()-fi(d 0 U(s)=- School of Mechanical Engineering ME369-Lecture 4.2 Shanghai Jiao Tong University Fall 2015 例3]绘制方块图（续） U,(s)-U(s) U(s)-U.(s =1,(s) R =1s) R Us=4-s） U.=40 Cs Cs School of Mechanical Engineering ME369-Lecture 4.2 Shanghal Jiao Tong University Fall 2015 5
5 ME369-Lecture 4.2 Fall 2015 School of Mechanical Engineering Shanghai Jiao Tong University 1 1 1 ( ) ( ) ( ) r u t u t i t R 1 1 2 1 1 u t i t i t t ( ) [ ( ) ( )]d C 1 2 2 ( ) ( ) ( ) c u t u t i t R 2 2 1 ( ) ( )d c u t i t t C 1 1 1 ( ) ( ) ( ) U s U s r I s R 1 2 1 1 ( ) ( ) ( ) I s I s U s C s 1 2 2 ( ) ( ) ( ) U s U s c I s R 2 2 1 ( ) ( ) U s I s c C s LT [例3]绘制方块图 ME369-Lecture 4.2 Fall 2015 School of Mechanical Engineering Shanghai Jiao Tong University 1 1 1 ( ) ( ) ( ) U s U s r I s R 1 2 1 1 ( ) ( ) ( ) I s I s U s C s 1 2 2 ( ) ( ) ( ) U s U s c I s R 2 2 1 ( ) ( ) U s I s c C s [例3]绘制方块图（续）