cstr_pid.m

本程序用来实现CSTR模型的模糊PID控制仿真

% 本程序用来实现CSTR模型的PID控制仿真
% 
%   完成日期：2007年6月13日

clear

% 仿真参数
N = 200;
h = 0.1;

% 控制变量初值
Q(1) = 100.0;
Qc(1) = 15.0;

% 状态变量初值
Ca(1) = 0.037;
T(1) = 402.35;
Tc(1) = 345.44;
H(1) = 6.0; % 单位是分米

% 被控变量设定值
Cas = 0.06;
Ts = 405.0;
Tcs = 350.0;

% PID调节参数
% 控制Ca
% Kp = 20.0;  
% Ti = 0.1;
% Td = 0.0;  

% 控制T
% Kp = 1.5;  
% Ti = 1.0;
% Td = 0.0;  

% 控制Tc
Kp = 0.5;  
Ti = 0.2;
Td = 0.0;  

q0 = Kp*(1+h/Ti+Td/h);
q1 = -1*Kp*(1+2*Td/h);
q2 = Kp*Td/h;

% 误差变量
ek = 0;
ek_1 = 0;
ek_2 = 0;

% 控制仿真
for i = 1:N 
%     % 控制生成物浓度Ca
%     ek_2 = ek_1;
%     ek_1 = ek;
%     ek = Cas-Ca(i);
%     e(i) = ek;
%     
%     dQ = q0*ek+q1*ek_1+q2*ek_2;
%     Q(i+1) = Q(i)+dQ;

%     [Ca(i+1), T(i+1), Tc(i+1), H(i+1)] = CSTR_RK4(Q(i+1), Qc, Ca(i), T(i), Tc(i), H(i));
    
%     % 控制反应温度 T
%     ek_2 = ek_1;
%     ek_1 = ek;
%     ek = Ts-T(i);
%     e(i) = ek;
%     
%     dQc = q0*ek+q1*ek_1+q2*ek_2;
%     Qc(i+1) = Qc(i)-dQc;
%     
%     [Ca(i+1), T(i+1), Tc(i+1), H(i+1)] = CSTR_RK4(Q, Qc(i+1), Ca(i), T(i), Tc(i), H(i));

    % 控制冷却液温度 Tc
    
    ek_2 = ek_1;
    ek_1 = ek;
    ek = Tcs-Tc(i);
    e(i) = ek;
    
    dQc = q0*ek+q1*ek_1+q2*ek_2;
    Qc(i+1) = Qc(i)-dQc;
    
    [Ca(i+1), T(i+1), Tc(i+1), H(i+1)] = CSTR_RK4(Q, Qc(i+1), Ca(i), T(i), Tc(i), H(i));
end

% figure(1)
% plot(Ca)
% grid on

% figure(2)
% plot(T)
% grid on
% 
figure(3)
plot(Tc)
grid on
% 
figure(4)
plot(Qc)
grid on

% figure(5)
% plot(Q)
% grid on