PID matlab 程序.txt

ts = 0.001;
sys  = tf (400,[1 ,50,0]);
dsys = c2d (sys,ts,'z');
[num,den] = tfdata(dsys,'v');
u_1  = 0.0 ;u_2 = 0.0; u_3 = 0.0 ;
y_1 = 0   ; y_2 = 0;   y_3 = 0;
x =  [0, 0 ,0];
error_1 = 0;
error_2 = 0;
for k=1:1:1000
  time(k) = k*ts;
  rin(k) = 1.0;
  kp = 8;
  ki = 0.10;
  kd = 10;
  du(k) = kp*x(1) + kd*x(2) + ki*x(3);
  u(k) = u_1 + du(k);
  if u(k) >= 10;
     uk = 10;
  end
  if u(k) <= -10 ;
  u(k) = -10;
  end
  yout(k) = -den(2)*y_1 - den(3)*y_2 + num(2)*u_1 +num(3)*u_2;
  error = rin(k) - yout(k);
  u_3 = u_2 ; u_2 = u_1; u_1 = u(k);
  y_3 = y_2 ; y_2 = y_1; y_1 = yout(k);
  x(1) = error - error_1;
  x(2) = error - 2*error_1 + error_2 ;
  x(3) = error;