Page 151 - Practical Control Engineering a Guide for Engineers, Managers, and Practitioners
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12& Cha11ter File
Or-~~==~~--:-~;;~r---~~~~
J ~E :: :··l··:··<:.;·.trt;·r~~:'.~~:~f~.:~ .. t~;-1~.::: :::: ~~:~7~~:
-300to-3 to- 2 to- 1 tOO
Frequency
F1aURI 6-3 Bode plot of three-tank process with no backflow.
These equations can be rewritten compactly using matrices
which are discussed in App. G. It is shown there that Eq. (5-6) can be
written as
1
-- 0 0
t'l
~(~:)= ~_.!_ 1 0 (~}[~]Fo
dt X ~ t'2 t'2
3 ~1 1
0 (5-7)
~ t'3 t'3
1{~:)
Y=(O 0
In general, many linear models of processes can be written to fit
the general format of
d
-X=AX+BU
dt (5-8)
Y=CX
