Dc Link Power P; Dc,Mot Of Motoring Axis; Dc,Gen Of Regenerating Axis - ABB ACS850 Application Manual

Drive Drive
A B
M M

DC link power P

of motoring axis
dc,mot
is the power supplied to the DC terminals to get the required mechanical
P
dc,mot
motoring power on the motor shaft. P
also covers the losses in the drive and motor.
Drive losses
Motor losses
P
m
: DC link power
P
dc
: efficiency factor (1/eff) to include drive and motor losses. If not known, value
k
eff
1.25 can be used.
: motor mechanical shaft power
P
m
: torque (Nm) on motor shaft
T
: motor shaft speed (rpm)
n
DC link power P of regenerating axis
dc,gen
is now the power supplied from the regenerating motor to the DC terminals.
P
dc,gen
is lower than the shaft power, because the shaft power now covers also the
P
dc,gen
losses in the drive and motor.
Drive losses
Motor losses
P
dc,gen
Based on the system power profile, the following system level DC link power values
are defined.
Drive
C
M
dc,mot
=
P k
dc , mot
P
dc,mot
≈
P ( kW )
m
P
dc , gen
P
m
is higher than the shaft power, because it
×
P
eff m
×
T n
9550
P
= ×
m
k
eff
Common DC configurations
17