GE AV-300i User Manual page 162

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When PID MltPI selmon = 0 and the PI Block is disabled, the system keeps into memory the last
calculated value of PID out mon. In case the machine is switched off, such value is automatically
reset. In case the value of this parameter has to be set in order to have on the output a wrong
reference equal to the feed-forward, it is possible to configure a digital input as a correction reset.
It is therefore necessary to:
select Mlt PI sel 0
set PID Mlt PI sel 1
By bringing the digital input to a high logic level, the value of PID out mon is set at 1.
Set PI lim top and PI lim bot according to the winder diameter ratio.
The PI lim top and PI lim bot parameters can be considered, respectively, as a maximum and minimum multi-
plicative factor of the feed-forward.
Considering that the motor angular speed, and therefore the reference, are inversely proportional to the winding/
unwinding diameter, set:
PI lim top = 1
PI lim bot = Fmin / Fmax = 100 / 700 = 0.14
Here following is a description of the above statements.
Calculation of the motor angular speed:
ω max. = Vl / (Φ x Fmin x R)
e
ω min = Vl / (Φ x Fmax. x R)
where:
ω max. = motor angular speed with a minimum diameter [rpm]
ω min = motor angular speed with a maximum diameter [rpm]
Vl = line speed
Φmin = winder minimum diameter [m]
Φmax. = winder maximum diameter [m]
R = motor-winder reduction ratio
Therefore: ω max. / ω min = Φmax. / Φmin
where
ω min = (Φmin / Φmax) x ω max.
Consider that the PI lim top and PI lim bot parameters can be considered, respectively, as a maximum and
minimum multiplicative factor of the feed-forward.
Multiply the feed-forward by PI lim top = 1, the result is the maximum speed reference referring to the mini-
mum diameter.
Multiply the feed-forward by PI lim bot = 0.14, the result is the minimum speed reference referring to the
maximum diameter.
Ch.1
162
GEH-6641E
= DI 4 monitor
= 1
—————— Function Description ——————