Suppose that we initialize the A,B,C,D arrays of the steady state representation as follows:
A = [-1, 2, 0; 2, 1, 0; -2, -1, 0];
B = [1, 1; -1, 2; 1, -2];
C = [1,-1, 0; -1, 0, 0];
D = zeros(2,2);
If we try to find the zeros and poles of the MIMO system above we end up with different results when using the state space representation and the transfer function:
fprintf('ss representation:\n\n');
fprintf('zeros:\n');
tzero(ss_sys)
fprintf('poles:\n');
pole(ss_sys)
fprintf('tf representation:\n\n');
fprintf('zeros:\n')
tzero(tf_sys)
fprintf('poles:\n');
pole(tf_sys)
ss representation:
zeros:
ans =
0
poles:
ans =
-2.2361
2.2361
0
tf representation:
zeros:
ans =
-2.2361
2.2361
poles:
ans =
2.2361
-2.2361
2.2361
-2.2361
Why is this happening? Which representation should we choose each time we want to calculate the properties of the system?
Thanks in advance,
