Hello all,

I need to use optimal control theory to design a controller
(K),(Integrator op-amp) for my circuit. Basically, I have two inputs and
one output, and below are the transfer functions of my circuit:

G1(s)= -3000*(s+333.33) / ( (s-539667) (3*s+1000) )


G2(s) = 5040000*(s+333.333)/ ( (s-539667) (3*s+1000) )

In order to use optimal control theory to design a controller (K), I need
to determine the matrix Q (state weighting matrix) , and R (control
weighting matrix),but I'm not really sure how to get them.Can I assume Q
is an identity matrix and R = 1?. Can you please help me on this.

Thanks a lot for your help and support.

 

hi

you will have to tune them according to your requirement. these are tuning parameters. thsi is basically trial and eror method.

regards
rakesh singhal

 

Moin Anonymous,
moin all,

Starting with identity matrices for R and Q is ok. You will have to simulate your closed-loop system and check the responses. Most likely it is not what you expect - e.g. too large or too small control actions or not fast enough. Then you modify R and Q and simulate again. In most cases R and Q remain diagonal matrices. please note, optimal control (Riccati) is a try and error method.

Best regards
Friedrich Haase

Ing.-Büro Dr. Friedrich Haase
Consulting - Automatisierungstechnik
email [email protected]
WEB http://www.61131.com