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The more precise the value of the moment of inertia in the converter, the lower the overshoot
after speed changes.
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Figure 8-59
Influence of the moment of inertia on the speed
Function description
The converter calculates the total moment of inertia of the load and motor. The calculation
comprises the following components:
• Current speed
• Actual motor torque
• Reduce the load
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Figure 8-60
Overview of the function of the moment of inertia estimator
When using the moment of inertia estimator, we recommend that you also activate the friction
characteristic.
Friction characteristic (Page 301)
How does the converter calculate the load torque?
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Figure 8-61
Calculating the load torque
Advanced commissioning
8.19 Motor control
Distributed converter for SIMOGEAR geared motors
304
Operating Instructions, 10/2020, FW V4.7 SP13, A5E31298649B AL