GE Industrial Solutions DV-300 DC Drive Users Manual - Manual (Page 297)

DV-300 Adjustable Speed Drives
——— FUNCTION DESCRIPTION ———
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Set Analog input 3 as input for the pressure setting (PID offset 0).
Analog input 3 / Select input 3 / PID offset 0
Set Digital input 1 as enabling input for the PI block of the PID
Digital input 1 = Enable PI PID
Set Digital input 2 as enabling input for the PD block of the PID
Digital input 2 = Enable PD PID
parameters
Set Speed base value equal to the motor nominal speed .
Speed base value = 3000rpm
Set PID source as Ramp output.
For PID source set the parameter number to which it will be associated, choosing it from the list of section 10.4.
“List of high priority parameters” (Ramp output has the decimal number113).
To obtain the correct value it must be added the decimal value 8192 (fixed offset):
PID source = (8192 + 113) = 8305
Set PID source Gain so that Feed-fwd PID, along with the maximum value of Ramp output (corresponding
to the maximum value of the analog input 2), reaches 100% of its value = 10000.
The ramp reference and its output automatically acquire their maximum value from the setting of Speed base
value. Therefore it must be taken into consideration that each writing or reading of any parameter concerning
the speed is defined as RPM x 4.
So: PID source Gain = max Feed-fwd PID / (Speed base value x 4) = 10000 / (3000 x 4) = 0.833
Set PID target as Speed ref 1.
n
ote
: When the ramp function is enabled, Speed ref 1 is not available. In order to make it available
it is necessary to set the parameter Enable ramp = Disable. (This setting allows the working
of the ramp block, but disconnects its output from the speed reference 1).
For PID target, set the parameter number to which it will be associated, choosing it from the list of the section
10.4. “List of high priority parameters” (Speed ref 1 has the decimal number 42). To obtain the correct value it
must be added the decimal value 8192 (fixed offset):
PID target = 8192 + 42 = 8234
Set PID out scale so that the maximum analog value on Analog input 2 (Feed-fwd PID = 10000) and with
Enable PI PID and Enable PD PID = Disable, Speed ref 1 were equal to 3000rpm.
The Speed ref 1 must be set as RPM x 4, then:
PID out scale = (3000 x 4) / 10000 = 1.2
Set PI central v sel = 1.
Set PI central v 1 = 1
In absence of correction performed by the PI block of the regulator, the line reference speed (Feed-forward) must
be multiplied x 1 and sent directly to the speed regulator of the drive.
In this application, the regulator makes a proportional-integral control.
Set PI top limit and PI bottom limit in order to obtain maximum correction of the PI block equal to the 100%
of the speed reference.