DC 모터에서 전류 제어를 LQR 제어기로 하고싶은데 simulink를 어떻게 만들어야 하나요?

현재 PMDC까지는 구현을 했고 전류 컨트롤러에서 PID로 하는 방법은 알겠는데 LQR을 어떻게 하는 지 모르겠네요,,,

Answer 1

[Amish]

Hi 주환 엄,

You can use MATLAB to compute the "LQR gain matrix" (K). The LQR controller minimizes a cost function of the form:

where "Q" and "R" are user-defined weight matrices that penalize the state and control input, respectively. This can be solved using MATLAB as follows:

% Define the state-space matrices
% Your A,B,C,D matrices
A = [..]; 
B = [..]; 
C = [..]; 
D = [..]; 

% Define the weight matrices
Q = [..]; 
R = [..]; 

K = lqr(A, B, Q, R); % Compute the LQR gain

This can then be implemented in Simulink with the help of various blocks. You will need the following:

• State-Space block: to represent the PMDC motor model (with Matrices A,B,C,D)
• Gain block: to represent the LQR gain (K) , this is computed previously
• Sum block: to compute the control input
• Scope block: to visualize the output
• Step block: for the input voltage

You can then set your required parameters and run the Simulation.

For more information you can refer to the following documentation:

LQR: https://www.mathworks.com/help/control/ref/lti.lqr.html

DC Motor Control: https://www.mathworks.com/help/control/ug/dc-motor-control.html

Hope this helps!