ABB REG670 Applications Manual

Where
U
N
is the rated voltage of the generator
X
d
’’ is the subtransient reactance for the generator (Ω)
X
T
is the reactance of the step-up transformer (Ω)
Z
network
is the short circuit source impedance of the connected network recalculated to the
generator voltage level (Ω)
The setting can be chosen:
I to be less than I
energisation
> ⋅0 8.
EQUATION2283 V2 EN (Equation 239)
tOC: Time delay for trip in case of high current detection due to accidental energizing
of the generator. The default value 0.03s is recommended.
ArmU<: Voltage level, given in % of UBase, for activation (arming) of the accidental
energizing protection function. This voltage shall be lower than the lowest operation
voltage. The default value 50% is recommended.
tArm: Time delay of voltage under the level Arm< for activation. The time delay shall
be longer than the longest fault time at short circuits or phase-earth faults in the
network. The default value 5s is recommended.
DisarmU>: Voltage level, given in % of UBase, for deactivation (dearming) of the
accidental energizing protection function. This voltage shall be higher than the
ArmU< level. This setting level shall also be lower than the lowest operation voltage.
The default value 80% is recommended.
tDisarm: Time delay of voltage over the level DisarmU> for deactivation. The time
delay shall be longer than tOC. The default value 0.5s is recommended.
9.14 Voltage-restrained time overcurrent protection
VRPVOC
9.14.1 Identification
Function description
IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Voltage-restrained time overcurrent
protection
VRPVOC I>/U< 51V
Section 9 1MRK 502 071-UEN -
Current protection
394 Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
Application manual

ABB REG670 Specifications

General

Brand	ABB
Model	REG670
Category	Protection Device
Language	English