Siemens SINAMICS S120, Function Manual

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Function modules
8.12 Moment of inertia estimator
Drive functions
588
Function Manual, 11/2017, 6SL3097-4AB00-0BP5
8.12.3 Supplementary functions of the moment of inertia estimator for vector control
Moment of inertia precontrol
In applications where the motor predominantly operates with a constant speed, the converter
can only infrequently calculate the moment of inertia using the function described above.
Moment of inertia precontrol is available for situations such as these. The moment of inertia
precontrol assumes that there is an approximately linear relationship between the moment of
inertia and the load torque.
Note
Moment of inertia precontrol is only possible for vector control. The "Moment of inertia
estimator" function module must be activated.
Configuring moment of inertia precontrol
1.
Ensure that the acceleration precontrol scaling is not equal to zero: p1496 ≠ 0.
2. Activate the acceleration model of the speed controller precontrol: p1400.20 = 1.
3. Configure the moment of inertia precontrol using p5310.
Using bit 0, you can activate the calculation of the characteristic (p5312 … p5315)
Using bit 1, you can activate the moment of inertia precontrol. The following bit
combinations are possible:
p5310.0 = 0,
p5310.1 = 0
Moment of inertia precontrol not active
p5310.0 = 0,
p5310.1 = 1
Cyclic calculation of the coefficients without moment of inertia precon-
trol (commissioning)
p5310.0 = 1,
p5310.1 = 0
Moment of inertia precontrol activated (without cyclic calculation of the
coefficients)
p5310.0 = 1,
p5310.1 = 1
Moment of inertia precontrol activated (with cyclic calculation of the
coefficients)
The status word of the moment of inertia precontrol is indicated in r5311.