Nidec Leroy-Somer Powerdrive MD Smart, Integration Manual

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HARDWARE SELECTION
Powerdrive MD Smart Integration Guide
5751 en - 2021.10 / e
HARDW
ARE
SELECTION
2.2.4 - Low frequency (Lf) correction factor
At low output frequencies (motor), the IGBT modules of the inverter component are subjected to significant temperature cycling,
which may decrease their lifetime.
To prevent this risk, the curve below indicates the derating of the Isp and Imax output currents indicated in the design table in §2.3
when operating at low motor frequencies in constant speed.
2.2.5 - Choosing the chopping frequency
The rated chopping frequency of the Powerdrive MD Smart variable speed drive is 3 kHz.
If the user decides to increase this value, it is necessary to downgrade the standard Isp continuous output current. The variable
speed drive component selection tables in §2.3 take this derating into account and indicate the Isp values for a chopping frequency
value of 4, 6 and 8 kHz.