% Step response of rector model

k=2/125;                             % Gain from u to y
T1=1/125;                            % Time constant
T2=T1;                               % 2nd time constant
tau=1/250;                           % Inverse response time constant

s=tf('s')                            % Define Laplace operator

hp=k*(1-tau*s)/((1+T1*s)*(1+T2*s));  % Plant model transfer function

step(hp)
grid