实验六 Simulink子系统封装

实验六Simulink子系统封装
The electronic circuit in the following figure consists of a voltage source, a resistor, and an inductor in the form of a tightly wound coil. An iron ball beneath the inductor experiences a gravitational force as well as an induced magnetic force (from the inductor) that opposes the gravitational force.
A differential equation for the force balance on the ball is given by
where M is the mass of the ball, h is the height (position) of the ball, g is the acceleration due to gravity, i is the current, and βis a constant related to the magnetic force experienced by the ball. This equation describes the height, h, of the ball due to the unbalanced forces acting upon it.
The current in the circuit also varies with time and is given by the following differential equation
where L is the inductance of the coil, V is the voltage in the circuit, and R is the resistance of the circuit.
The system of equations has three states
The system also has one input (V), and one output (h). It is a nonlinear system due to the term in the equation involving the square of i and the inverse of h.
Values of the parameters are given as: M=0.1 kg, g=9.81 m/s2, R=2 Ohm, L=0.02 H, β=0.001
1、在Simulink建立以上描述的系统的框图模型,并将其封装为子系统(模块)，如
下图所示：
图1 框图模型
图2 封装后的模块及参数设置窗口
2、设计一个PID控制器，控制h保持在0.05。

在如下图所示：
图3 控制系统
图4 PID 控制器
以下值可供参考：
P = 537.2672
I = 1000
D = 60.4787
2．数据的输出
命令窗口输出函数主要有disp 函数，其调用格式为 disp(输出项)
其中输出项既可以为字符串，也可以为矩阵。

例4.2 求一元二次方程ax2 +bx+c=0的根。

a=input('a=?');
b=input('b=?');
c=input('c=?');
d=b*b - 4*a*c;
x=[(-b+sqrt(d))/(2*a), (-b-sqrt(d))/(2*a)];
disp( ['x1=', num2str(x(1)), ',x2=', num2str(x(2))] );
⎪⎩⎪⎨⎧≠+=+++=10x ,x x x 10x ,1x )1x cos(y 2
x=input('请输入x的值:');
if x==10
y=cos(x+1)+sqrt(x*x+1);
else
y=x*sqrt(x+sqrt(x));
end
Y
A=[1,2,3;4,5,6]; B=[7,8,9;10,11,12];
try
C=A*B;
catch
C=A.*B;
end
C
lasterr %显示出错原因。