Configuring the motor 5.1 Procedure
Recalculating the duty cycle
If the moment of inertia initially assumed deviates significantly from the actual moment of inertia, the duty cycle may have to be recalculated.
5.1.10Selecting the drive system components for the power connection
The drive system components for the power connection are selected on the basis of the peak and continuous currents that occur in the duty cycle. If more than one motor is operated in parallel on a single power unit, the total values of the peak and continuous currents must be taken into account.
Note
In systems where direct drives are used on controlled infeeds, electrical oscillations can occur with respect to ground potential. These oscillations are, among other things, influenced by:
∙The lengths of the cables
∙The rating of the infeed/regenerative feedback module
∙The number of axes
∙The size of the motor
∙The winding design of the motor
∙The type of line supply
∙The place of installation
The oscillations lead to increased voltage loads and may damage the main insulation! We thus recommend using an HFD commutating reactor with damping resistance for damping the oscillations. For specific details, refer to the documentation of the drive system being used or contact your local Siemens office.
5.1.11Calculating the required infeed power
Infeed power
The electrical infeed power of the motors can be determined from the mechanical power delivered and the resulting electrical losses.
,
With
,
Here, M represents the motor torque in Nm, ω represents the angular velocity in 1/s, and kT represents the torque constant of the motor in Nm/A (see also "Explanations of the formula abbreviations)".
70 | 1FW6 |
Configuration Manual, 05/2009, |
