what is the code to implement a disturbance of 0.2 in the system at 400 sec that would test the disturbance rejection of the controller and allow the system to return to 1?

Question

sabavath jayaram 2023-2-28

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1920285-what-is-the-code-to-implement-a-disturbance-of-0-2-in-the-system-at-400-sec-that-would-test-the-dist

回答： Sam Chak 2023-2-28

Hi All,

Can anyone help me with MATLAB code for a disturbace of 0.2 at 400 seconds that would test the disturbance rejection of the PID controller and allow the system to return to 1?

I need to test the tuning by applying a disturbance at 400 seconds to see how the controller responds in that case in MATLAB code.

Help very much appreiciated!!

Thanking you

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Sam Chak 2023-2-28

Hi @sabavath jayaram

Since your system is not provided, here is a simple example to demonstrate the disturbance rejection capability of a PID controller for a Double Integrator system.

s = tf('s');

m = 5;

Gp = 1/(m*s^2) % Plant

Gp = 1 ----- 5 s^2 Continuous-time transfer function.

% PID controller

Kp = 2.460; % proportional gain

Ki = 0.324; % integral gain

Kd = 4.650; % derivative gain

N = 114.29; % 1st-order derivative filter coefficient

Gc = pid(Kp, Ki, Kd, 1/N)

Gc = 1 s Kp + Ki * --- + Kd * -------- s Tf*s+1 with Kp = 2.46, Ki = 0.324, Kd = 4.65, Tf = 0.00875 Continuous-time PIDF controller in parallel form.

margin(Gc*Gp)

% closed-loop transfer function from Disturbance R(s) to Output Y(s)

Gcd = feedback(Gp, Gc)

Gcd = s^2 + 114.3 s ----------------------------------------------- 5 s^4 + 571.5 s^3 + 533.9 s^2 + 281.5 s + 37.03 Continuous-time transfer function.

step(Gcd), grid on % Response to a Unit step disturbance

If the output response to a unit step disturbance D(s) = 1 goes to zero in 50 seconds, then rest assured that the output will track the unit step reference R(s) = 1.

% closed-loop transfer function from Reference R(s) to Output Y(s)

Gcl = feedback(Gc*Gp, 1)

Gcl = 533.9 s^2 + 281.5 s + 37.03 ----------------------------------------------- 5 s^4 + 571.5 s^3 + 533.9 s^2 + 281.5 s + 37.03 Continuous-time transfer function.

step(Gcl, 60), grid on % Step Response