ABB ACS 600 MultiDrive, Руководство пользователя

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Chapter 6 – Firmware Description
ACA 635 IGBT Supply Sections 6-15
When the current limit alarm is active, the internal control first lowers
the ramped reactive power reference (when Par. 24.01 Q POWER
REF is not zero) controlling the current towards the current limit. In
case the current limit is not reached (when the ramped reactive power
reference has been controlled to zero), the internal control, secondly,
lowers the ramped d.c. reference, further controlling the current
towards the current limit. In case the current limit is still not reached
(current limit alarm is still active and the ramped d.c.reference equals
the value of Par. 2.05 DC REF Q-CTRL), the current can be lowered by
limiting inverter actual power.
The alarm is removed when the current falls below the current limit.
A block diagram of the current limit alarm is presented below.
The current limit parameters are presented below.
Reactive Power Control The base value for the flux reference is Parameter 150.01 FLUX REF
USED NOM. The DC voltage and output voltage references are
defined during identification routine for setting cosfii to 1.0. However,
the voltage level in the network can fluctuate greatly. To have cosfii
equal to 1.0 at every point, the DC voltage and output voltage
references have to be adapted.
The reactive power control sets the output voltage reference (Actual
Signal 2.05 DC REF Q-CTRL) and the flux length reference
(Parameter 130.02 FLUX SQ REF) to values with which zero reactive
power is achieved.
Code Parameter Unit Description
137.04 CURRENT LIMIT % Current limit
137.01 TORQUE REF MAX % Absolute torque limit
1.06 161.03 LINE CURRENT A Measured line current (actual value)
145.03 DC OVERVOLT TRIP V
Alarm
9.12 bit 5 CURRENT LIM Current limit alarm
Fault
9.01 bit 1 OVERCURRENT Overcurrent fault
9.11 bit 15 DC OVERVOLT DC overvoltage fault
a > b = 1
COMPARATOR
1.06
LINE CURRENT
137.04
CURRENT LIMIT
9.12 bit 5
CURRENT LIM
a
b