Bosch Rexroth IndraDrive Mi Project Planning Manual page 111

Project Planning Manual | Rexroth IndraDrive Mi
Derating of Peak Power
Data used for the diagrams:
● Maximum peak current of 3 × I
● Threshold of braking resistor in supply unit or converter: 820 V
See also "P-0-0833, Braking resistor threshold"
See also "P-0-0860, Converter configuration"
Peak Power When Accelerating
P Peak power of KSM01
LN_max
P Peak power KCU01
DC_max
Fig.7-14: Peak power KCU01
As the length of the hybrid cable increases, the peak power available at the
cable end is reduced.
Peak power to be dimensioned depending on the cable length
Due to occurring voltage drops, the effective length of the motor
cable influences the available peak power at the distributed servo
drive KSM01.
Observe the following diagrams and the sections
● "Peak Power When Accelerating" and
● "Peak Power When Decelerating".
To calculate the occurring peak power, use the formulas from the
chapter "Calculations" of the Project Planning Manual "Rexroth In‐
draDrive, Drive System".
: 75A
Bypass
A) Peak power when decelerating
B) Acceleration power (n < 80%)
C) Acceleration power (n < 90%)
P Maximum peak power
P
l Cable length
Fig.7-15: Available peak power vs. cable length for DC 500 V and DC 750 V
Due to the voltage drop, less peak power is available at KSM01 with increasing
length of the motor cable. During acceleration, this becomes noticeable by the
reduction of the corner speed. The figure shows exemplary curves of reduction
to 80% and 90% of the data sheet corner speeds. The maximum speed is pro‐
portional to the DC bus voltage available at the motor.
Electric Drives | Bosch Rexroth AG
and Controls
Notes on Project Planning
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