Specifications

LQG Regulation: Rolling Mill Example
10-43
lsim(Py(1,2:3),':',cly(1,2:3),'-',wy,t)
The dotted lines correspond to the open-loop response. The simulation results
arecomparabletothoseforthe -axis.
Cross-Coupling Between Axes
The / thickness regulation, is a MIMO problem. So far you have treated
each axis separately andclosed one SISO loop at a time. This design is valid as
long as the two axes are fairly decoupled. Unfortunately, this rolling mill
process exhibits some degree of cross-coupling between axes. Physically, an
increase in hydraulic force along the -axis compresses the material, which in
turnboosts the repelling force on the -axis cylinders. The resultisanincrease
in -thickness and an equivalent (relative) decrease in hydraulic force along
the -axis.
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