cp4_4.m

离散控制系统设计的MATLAB 代码

%%%%%%%%%%% Comprehensive Problem 4.4 %%%%%%%%%%%
%   Discrete-Time Control Problems using        %
%       MATLAB and the Control System Toolbox   %
%   by J.H. Chow, D.K. Frederick, & N.W. Chbat  %
%         Brooks/Cole Publishing Company        %
%                September 2002                 %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Hydro-turbine System

clear
disp('Comprehensive Problem 4.4')
disp('PI control of hydro-turbine system')

dhydro  % read data
disp('*****>'), pause

disp('Poles of hydro-turbine system')
pole(Gz)
disp('Magnitude of hydro-turbine poles')
abs(ans)
disp('Zeros of hydro-turbine system')
tzero(Gz)
disp('*****>'), pause

disp('System in modal form')
Gz = canon(Gz,'modal')
disp('*****>'), pause

disp(' ')
disp('Hydro-turbine system with PI controller')
disp('                     Ts * z  ')
disp('Gc(z) = K_P (1 + K_I ------ )')
disp('                       z-1   ')
disp('K_P = 0.5 and K_I = 0.4') 

K_P = 0.5
K_I = 0.4
G_c = K_P*ss(1 + tf(K_I*Ts*[1 0],[1 -1],Ts))
disp('*****>'), pause

disp('Open-loop compensated system')
G_OL = Gz*G_c 
disp('*****>'), pause

disp('Closed-loop system transfer function ')
T_PI = feedback(G_OL,1)
disp('*****>'), pause

disp('DC gain of closed-loop system')
dcgain(T_PI)
disp('*****>'), pause

disp('Step response of hydro-turbine to step reference input')
figure
[y,dt] = step(T_PI);
plot(dt,y,'o')
xlabel('Time (s)')
ylabel('Amplitude')
title('CP4.4: Closed-loop Response of Power P to Unit Step of Reference Input')
grid
disp('*****>'), pause

disp('end of Comprehensive Problem 4.4')
%%%%%%%%%%