ABB ACSM1 Series, Руководство по прошивке

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Drive control and features
41
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 (e.g. UPS) which keeps the contactor control circuit closed during a short
supply break.
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
1.19 USED SUPPLY
VOLT . The DC voltage ( U
DC
) equals 1.35 times this value.
Automatic identification of the supply voltage is performed every time the drive is
powered. Automatic identification can be disabled by parameter
47.03
130
260
390
520
1.6 4.8 8 11.2 14.4
t (s)
U
DC
f
out
T
M
U
DC
= intermediate circuit voltage of the drive, f
out
= output frequency of the drive,
T
M
= motor torque
Loss of supply voltage at nominal load (f
out
= 40 Hz). The intermediate circuit DC voltage drops to the
minimum limit. The controller keeps the voltage steady as long as the mains 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.
U
mains
20
40
60
80
40
80
120
160
T
M
(Nm)
f
out
(Hz)
U
DC
(VDC)