Siemens SINAMICS G120X, Руководство по эксплуатации

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8. Set p0340 = 4. The converter again calculates the speed controller parameters.
9. Switch on the motor.
10.Over the complete speed range check as to whether the speed control operates
satisfactorily with the optimized settings.
You have optimized the speed controller.
❒
When necessary, set the ramp-up and ramp-down times of the ramp-function generator
(p1120 and p1121) back to the value before optimization.
Mastering critical applications
The drive control can become unstable for drives with a high load moment of inertia and
gearbox backlash or a coupling between the motor and load that can possibly oscillate. In this
case, we recommend the following settings:
● Increase p1452 (smoothing the speed actual value).
● Increase p1472 (integral time T
I
): T
I
≥ 4 · p1452
● If, after these measures, the speed controller does not operate with an adequate dynamic
performance, then increase p1470 (gain K
P
) step-by-step.
Parameters
Table 6-98 Encoderless speed control
Number Name Factory setting
p0342[M] Ratio between the total and motor moments of inertia 1
p1452 Speed controller actual speed value smoothing time (enco‐
derless)
10 ms
p1470[D] Speed controller encoderless operation P gain 0.3
p1472[D] Speed controller encoderless operation integral time 20 ms
p1496[D] Acceleration precontrol scaling 0%
6.7.4 Electrically braking the motor
Overview
Braking with the motor in generator operation
If the motor brakes the connected load electrically, it converts the kinetic energy of the motor
into electrical energy. The electrical energy E released on braking the load is proportional to the
moment of inertia J of the motor and load and to the square of the speed n. The motor attempts
to pass the energy on to the converter.
Advanced commissioning
6.7 Motor control
SINAMICS G120X converter
398
Operating Instructions, 06/2019, FW V1.01, A5E44751209B AC