2.7_数学模型的Matlab描述.doc

数学模型的Matlab描述 传递函数模型可转化成零极点模型，也可转换成状态空间模型。 举例： % name:model_transform_01 clear,clc % 清除此前运行程序的变量，清屏 num1=5*[1,-5,6] den1=conv(conv([1,-1],[1,-1]),[1,2]) tfGs=tf(num1,den1) zpGs=zpk(tfGs) [z,p,k]=zpkdata(zpGs,v) ssGs=ss(tfGs) 运行结果： num1 = 5 -25 30 den1 = 1 0 -3 2 Transfer function: 5 s^2 - 25 s + 30 ----------------- s^3 - 3 s + 2 Zero/pole/gain: 5 (s-3) (s-2) ------------- (s+2) (s-1)^2 z = 3.0000 2.0000 p = -2.0000 1.0000 1.0000 k = 5 a = x1 x2 x3 x1 0 0.75 -0.25 x2 4 0 0 x3 0 2 0 b = u1 x1 4 x2 0 x3 0 c = x1 x2 x3 y1 1.25 -1.563 0.9375 d = u1 y1 0 Continuous-time model. 状态方程： 输出方程： 传递函数模型的串联 % series example clear,clc num1=[0,1];den1=[1,1]; num2=[0,2];den2=[1,2]; num3=[0,3];den3=[1,3]; Gs1=tf(num1,den1) Gs2=tf(num2,den2) Gs3=tf(num3,den3) Gs4=series(Gs1,Gs2) % Gs4=series(Gs1,Gs2,Gs3) is out of work Gs5=series(Gs4,Gs3) Gs6=Gs1*Gs2*Gs3 % multiple * are permitted 运行结果： Transfer function： 1 ----- s + 1 Transfer function: 2 ----- s + 2 Transfer function: 3 ----- s + 3 Transfer function: 2 ------------- s^2 + 3 s + 2 Transfer function: 6 ---------------------- s^3 + 6 s^2 + 11 s + 6 Transfer function: 6 ---------------------- s^3 + 6 s^2 + 11 s + 6 传递函数模型的并联 % parallel example clear,clc num1=[0,1];den1=[1,1]; num2=[0,2];den2=[1,2]; num3=[0,3];den3=[1,3]; Gs1=tf(num1,den1) Gs2=tf(num2,den2) Gs3=tf(num3,den3) Gs4= parallel (Gs1,Gs2) % Gs4= parallel (Gs1,Gs2,Gs3) is out of work Gs5= parallel (Gs4,Gs3) Gs6=Gs1+Gs2+Gs3 % multiple + are permitted 运行结果： Transfer function: 1 ----- s + 1 Transfer function: 2 ----- s + 2 Transfer function: 3 ----- s + 3 Transfer function: 3 s + 4 ------------- s^2 + 3 s + 2 Transfer function: 6 s^2 + 22 s + 18 ---------------------- s^3 + 6 s^2 + 11 s + 6 Transfer function: 6 s^2 + 22 s +