Siemens SIMATIC ET 200pro - Moment of Inertia Estimator

Setting functions
8.5 Motor control
SIMATIC ET 200pro FC-2 converter
126 Operating Instructions, 04/2015, FW V4.7.3, A5E34257324B AB
Parameter
Explanation
p3846
Friction characteristic plot ramp-up/ramp-down time
(factory setting: 10 s)
Ramp-up/ramp-down time for automatic plotting of the friction characteristic.
p3847
Friction characteristic plot warm-up period
(factory setting: 0 s)
At the start of automatic plotting, the inverter accelerates the motor up to the speed =
p3829 und keeps the speed constant for this time.
You will find more information in the List Manual.
8.5.2.5
Moment of inertia estimator
Background
From the load moment of inertia and the speed setpoint change, the inverter calculates the
accelerating torque required for the motor. Via the speed controller precontrol, the
accelerating torque specifies the main percentage of the torque setpoint. The speed
controller corrects inaccuracies in the precontrol (feed-forward control).
Figure 8-16 Influence of the moment of inertia estimator on the speed control
The more precise the value of the moment of inertia in the inverter, the lower the overshoot
after speed changes.
Figure 8-17 Influence of the moment of inertia estimator on the speed