Dc Voltage Control Features; Overvoltage Control; Undervoltage Control; Voltage Control And Trip Limits - ABB ACSM1 Firmware Manual

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For encoder interface module FEN-xx connection, see the User's Manual of the
appropriate encoder interface module.

DC voltage control features

Overvoltage control

Overvoltage control of the intermediate DC link is needed with two-quadrant
line-side converters when the motor operates within the generating quadrant. To
prevent the DC voltage from exceeding the overvoltage control limit, the overvoltage
controller automatically decreases the generating torque when the limit is reached.

Undervoltage control

If the incoming supply voltage is cut off, the drive will continue to operate by utilising
the kinetic energy of the rotating motor. The drive will be fully operational as long as
the motor rotates and generates energy to the drive. The drive can continue the
operation after the break if the main contactor remained closed.
Note: Units equipped with main contactor option must be equipped with a hold
circuit (eg, UPS) which keeps the contactor control circuit closed during a short
supply break.
T
M
(Nm)
160
120
80
40
U
DC
T = motor torque
M
Loss of supply voltage at nominal load (f
minimum limit. The controller keeps the voltage steady as long as the supply is switched off. The drive
runs the motor in generator mode. The motor speed falls but the drive is operational as long as the
motor has enough kinetic energy.

Voltage control and trip limits

The control and trip limits of the intermediate DC voltage regulator are relative either
to a supply voltage value provided by the user or to an automatically-determined
supply voltage. The actual voltage used is shown by parameter
VOLT. The DC voltage (U
Drive control and features
f U
out DC
(Hz) (VDC)
80 520
60 390
40 260
20 130
1.6
= intermediate circuit voltage of the drive, f
4.8 8
= output frequency of the drive,
out
= 40 Hz). The intermediate circuit DC voltage drops to the
out
) equals 1.35 times this value.
DC
U
mains
U
DC
f
out
T
M
t(s)
11.2 14.4
1.19 USED SUPPLY