ABB ACS 600 User Manual page 47

Chapter 6 – Firmware Description
Current Limit Control
6-14
The parameters and actual values of DC voltage control are listed
below.
Code Parameter
121.01 GAIN REL
121.02 DERIVATION TIME
121.03 GAIN REL CALC
121.04 DER TIME CALC
121.05 DC CTRL INTEG
Actual Value
161.07 TORQUE ACT
161.08 TORQUE FILT ACT
1.05 161.09 FREQUENCY
1.08 161.13 POWER
1.10 160.04 DC VOLTAGE
122.01 DC VOLTAGE ERROR
122.03 TORQUE CALC REF
122.04 TORQUE REF LIM
Because of the free wheeling diodes on the power plates, the
modulating ISU cannot limit the current when power flows from supply
network to the DC link. If the motoring power of the inverters increases
momentarily from the nominal level (allowed short term overload level),
current will flow from the network to the capacitors regardless of the
control. The waveform changes from sinusoidal to diode bridge mode
waveform, in which current peaks are considerably higher with the
same power. Overcurrent tripping limit is 98 percent of the maximum
value of the converter current measuring range (Parameter 4.08 CONV
MAX CURRENT).
During regeneration (braking) the current can be limited by means of
Parameter 137.01 TORQUE REF MAX. The calculated torque
reference (Parameter 122.03 TORQUE CALC REF) is limited to the
absolute value of Parameter 137.01 TORQ REF MAX, which is 220
percent of the ISU nominal "torque". Current limitation will cause a
voltage rise in the DC link. When the voltage reaches the limit of
Parameter 145.03 DC OVERVOLT TRIP, bit 15 DC OVERVOLT of
Parameter 9.11 SUPPLY FAULT WORD will be set and the ISU will
trip.
An alarm (Parameter 9.12 SUPPLY ALARM WORD bit 5 CURRENT
LIM) is generated, when the line current (Actual Signal 1.06 LINE
CURRENT) is exceeds the value of Parameter 137.04 CURRENT
LIMIT. Par. 137.04 CURRENT LIMIT is 220 percent of Parameter
112.02 HEAVY DUTY CUR which equals to I
so close to the overcurrent trip limit, that an alarm is rarely generated
(before an overcurrent trip).
Unit Description
% Initial gain
ms Initial derivation time
% Calculated relative gain
ms Calculated derivation time
ms Initial integration time
% Nonfiltered torque value
% Filtered torque value
Hz Calculated line frequency
kW Active power
V Actual DC voltage
V Error value between reference and
actual voltage
% PID controller output
% Torque hysteresis controller input
1base (10s/60s)
ACA 635 IGBT Supply Sections
. This limit is