Lenze DSD - Manual (Page 353)

Lenze · Drive Solution Designer · Manual · DMS 4.2 EN · 12/2013 · TD23
353
11 Drive Dimensioning
11.6 Inverters
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11.6.2 Preselection
In the following subchapters the parameters for the preselection of the inverter are described.
11.6.2.1 Motor output
11.6.2.2 Design
11.6.2.3 Switching frequency
According to the inverter, different settings of the switching frequency can be carried out. The
switching frequency can be selected between "variable" or "fixed".
• If a variable switching frequency is used, the respective maximum available switching frequen-
cy is specified. However, this switching frequency is not reached if the inverter is subjected to
higher loads.
• Depending on the modulation mode of the switching frequency, a power-optimised or loss-op-
timised operation of the inverter can be carried out.
Symbol Description
• Single axis
• Double axis
Symbol Description
• BaseLine
• StateLine
• HighLine
• TopLine
Symbol Description
f
ch,set
Switching frequency of the inverter
• At higher switching frequencies, acoustic motor noises and controller output currents are re-
duced. With a decreasing switching frequency, however, the losses in the motor increase.
• The preselection in the DSD corresponds to the Lenze setting of the inverter selected.
• Select the switching frequency at which the inverter is to be actuated.
• According to the selection, the respective rated data is displayed in the selection table.
• If the drive is to be actuated with a variable switching frequency, the max. possible output
current can only be reached with the lowest switching frequency.
• For inverters with a variable switching frequency in the Lenze setting, the lowest switching
frequency is to be selected.

Note!
Derating for the motor
• If the selected switching frequency is too low for the motor, a derating must be carried
out.