Siemens SINAMICS G110M - Page 194

Functions
8.6 Motor control
SINAMICS G110M Operating Instructions
194 Operating Instructions, 04/2015, FW V4.7.3, A5E31298649B AD
Function
From the actual speed, the actual motor torque and the frictional torque of the load, the
inverter calculates the total moment of inertia of the load and motor.
Figure 8-24 Overview of the function of the moment of inertia estimator
Calculating the load torque
At low speeds, the inverter calculates the load torque
M
L
from the actual motor torque.
The calculation takes place under the following co
n-
ditions:
•
Speed ≥ p1226
•
Acceleration setpoint < 8 1/s
2
(≙ speed change
480 rpm per s)
•
Acceleration × moment of inertia (r1493) < 0.9 ×
p1560