Eurotherm Drives 590 DRV Digital, Руководство по эксплуатации продукта

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Chapter 4 Start-up and Adjustment
590 DRV Digital drive Product Manual
3. Verify that SETUP PARAMETERS:: FIELD CONTROL:: FLD CURRENT VARS:: FLD WEAK
VARS:: FLD WEAK ENABLE is ENABLED:
4. Ensure that SETUP PARAMETERS:: FIELD CONTROL:: FLD CURRENT VARS:: FLD WEAK
VARS:: MIN FLD CURRENT is set correctly for the motor to reach top speed. MIN FLD CURRENT
is calculated using the formula:
(minimum field current ÷ maximum field current) × 90%
This sets MIN FLD CURRENT 10 percent lower than the field calculated to reach full speed. The
minimum and maximum field currents are found on the motor nameplate label. The 10 percent cushion
should overcome any inaccuracies in the nameplate data.
5. Adjust the maximum armature volts to 100 percent using parameter SETUP PARAMETERS:: FIELD
CONTROL:: FLD CURRENT VARS:: FLD WEAK VARS:: MAX VOLTS.
6. Run the drive up to base speed. Monitor DIAGNOSTICS:: TERMINAL VOLTS to verify that the
armature voltage is approximately equal to the value calculated in the previous step.
7. Increase speed above base speed by adjusting the speed potentiometer, checking that the motor armature
volts remain constant while the field gradually decreases. Gradually increase to maximum speed,
monitoring armature volts at maximum speed. Adjust the speed using the appropriate speed feedback
calibration parameters, for example ANALOG TACH CAL when using analog tachometer generator
feedback.
8. For regenerative, reversing drives, check the maximum reverse speed. Correct any asymmetry in a
reversing drive by adjusting SETUP PARAMETERS:: CALIBRATION:: ZERO SPD. OFFSET.
9. Stop the drive and SAVE PARAMETERS.
Enable FIELD
WEAKENING
Set MIN FIELD
CURRENT
Increase above
base speed &
speed track, if
necessary
Check Reverse
Speed
Save Parameters
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Set MAX VOLTS
to 100%
Run @ Base
Speed
Apply +10 VDC to
A3 thru Switch
Set Integral defeat
ON
Set A3 (INPUT 2
CAL) = 0.1000
1. Connect terminal B3 (+10 VDC) through a switch to
terminal A3. This will provide the step change input for
verifying speed loop performance.
2. Calibrate terminal A3 for 10% output by setting SETUP
PARAMETERS:: SPEED LOOP:: SETPOINTS:: RATIO
2 (A3) to 0.1000.
3. Set SETUP PARAMETERS:: SPEED LOOP:: INT.
DEFEAT to ON. This disables the integral gain.
4. Run the motor at a typical operating speed through the
speed ramp input, terminal A4. The speed should not
exceed 50 percent.
5. Check the speed loop performance by making step changes
using the switch at terminal A3. Increase SETUP PARAM-
ETERS:: SPEED LOOP:: PROP. GAIN until the response
is critically damped as illustrated above.
Set INPUT 3 (A4)
= +5 VDC
10 VDC
to A3
Adjust P Gain
Figure 4.2 - Response to Step Input
ADJUST SPEED LOOP
After calibrating the motor speed, tune the speed loop proportional gain (PROP. GAIN) and integral time constant
(INT. TIME CONST) settings for optimum speed response. For this procedure, monitor the speed feedback with an
oscilloscope at the Analog Tach test point pin on the control board (refer to Figure 5.19 in Chapter 5).
NOTE. Adjust the speed loop only after tuning the current loop with AUTOTUNE. Make certain the
motor is connected to the load it will normally be running.
PROP. GAIN scales the output based upon the input speed error. Increasing PROP. GAIN improves response time but
also increases overshoot. INT. TIME CONST eliminates steady-state error. Reducing INT. TIME CONST improves
response, but will cause instability if set too short.
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