Advanced commissioning
7.5 Motor control
Converter with control units CU250D-2
Operating Instructions, 04/2015, FW V4.7.3, A5E34261542B AB
159
Procedure
To activate the moment of inertia estimator, proceed as follows:
1.
Set p1400.18 = 1
2.
Check: p1496
≠
0
3.
Activate the acceleration model of the speed controller pre-control: p1400.20 = 1.
You have activated the moment of inertia estimator.
Parameter
Explanation
r0333
Rated motor torque [Nm]
p0341
Motor moment of inertia (factory setting: 0 kgm
2
)
The inverter sets the parameter when selecting a listed motor. The parameter is then
write-protected.
p0342
Moment of inertia ratio, total to motor (factory setting: 1)
Ratio of moment of inertia load + motor to moment of inertia of motor without load
p1400
Speed control configuration
.18 1 signal: Moment of inertia estimator active
.20 1 signal: Acceleration model on
.22 1 signal
Moment of inertia estimator retain value when motor switched off
0 signal
Moment of inertia estimator reset value to initial value J
0
when
motor switched off:
J
0
= p0341 × p0342 + p1498
If the load torque can change when the motor is switched off, set
p1400.22 = 0.
.24 1 signal
Accelerated moment of inertia estimator is active.
r1407
Status word, speed controller
.24 1 signal: Moment of inertia estimator is active
.25 1 signal: Load estimator is active
.26 1 signal: Moment of inertia estimator is engaged
.27 1 signal: Accelerated moment of inertia estimator is active.
r1493
Total moment of inertia, scaled
r1493 = p0341 × p0342 × p1496
p1496
Acceleration precontrol scaling (factory setting: 0 %)
According to rotating measurement of the motor data identification is p1496 = 100 %.
p1498
Load moment of inertia (factory setting: 0 kgm
2
)
p1502
Freeze moment of inertia estimator (factory setting: 0)
If the load torque changes when accelerating the motor, set this signal to 0.
0 signal
Moment of inertia estimator is active
1 signal
Determined moment of inertia is frozen
p1775
Motor model changeover speed encoderless operation
Defines the switchover between open-loop and closed-loop controlled operation of
the encoderless vector control.
When selecting the closed-loop speed control, the inverter sets p1755 = 13.3 % ×
rated speed.