Publicité
RE 30134/06.12 VT-VACAP-500-2X/V0/...
Controller adjustment
The P, I and D shares of the closed-loop control amplifier
are to be optimized according to the properties of the control
distance, the disturbance variables and the static and dy-
namic requirements on the control result.
1) Pressure controller ON – DIL 4 ON
2) Connection of an oscilloscope at the test point "p
3) Usefully connection of a 2nd oscilloscope channel at the
terminals "p
"
command
4) DIL 6 and DIL 7 serve to compensate dynamic differenc-
es in the pressure build-up and reduction in the system
DIL 6 ON = Normal application
OFF = Special application
DIL 7 ON = Normal application
OFF = Special application
5) DIL 13 reduces the pressure reduction by means of
a max. valve opening < approx. 15 %
ON = Special application
OFF = Normal application
6) Aim of the controller optimization
An optimum between change over characteristic (overshoot-
ing tendency with excessive static amplification) and static
accuracy (control error with starting pressure cut off) is to be
achieved (a).
Procedure (see table, page 11):
An increase in the P share of the controller increases the
dynamic of the control behavior (b). In case of excessive
gain, the tendency to oscillate increases (c).
Limitation of the I share reduces the static gain. With in-
creasing static gain, the control deviation is reduced (d). The
"
actual
D share can be used to influence the transition behavior
(minimization of the tendency to oscillate); thus, the com-
mand value is only reached after a longer transition time (f).
Hydraulics Bosch Rexroth AG
9/12
Publicité
Chapitres
