Voltage Differential Protection Vdcptov (60) - ABB REC670 Applications Manual

Section 9
Voltage protection
9.4
9.4.1
9.4.2
254
TDn: Time multiplier for inverse time characteristic. This parameter is used for co-
ordination between different inverse time delayed undervoltage protections.
ACrvn, BCrvn, CCrvn, DCrvn, PCrvn: Parameters for step n, to set to create
programmable undervoltage inverse time characteristic. Description of this can be
found in the technical reference manual.
CrvSatn: Set tuning parameter for step n. When the denominator in the expression of
the programmable curve is equal to zero, the time delay will be infinite. There will be
an undesired discontinuity. Therefore, a tuning parameter CrvSatn is set to compensate
for this phenomenon. In the voltage interval Pickup> up to Pickup> · (1.0 + CrvSatn/
100) the used voltage will be: Pickup> · (1.0 + CrvSatn/100). If the programmable
curve is used this parameter must be calculated so that:
CrvSatn
× - >
B C 0
100
EQUATION1448 V1 EN-US
HystAbsn: Absolute hysteresis for step n, set in % of VBase. The setting of this
parameter is highly dependent of the application. The hysteresis is used to avoid
oscillations of the PICKUP output signal. This signal resets when the measured voltage
drops below the setting level and leaves the hysteresis area. Make sure that the set
value for parameter HystABSn is somewhat smaller than the set pickup value.
Otherwise there is a risk that step n will not reset properly.

Voltage differential protection VDCPTOV (60)

Identification
Function description
Voltage differential protection
Application
The Voltage differential protection VDCPTOV (60) functions can be used in some
different applications.
• Voltage unbalance protection for capacitor banks. The voltage on the bus is
supervised with the voltage in the capacitor bank, phase- by phase. Difference
indicates a fault, either short-circuited or open element in the capacitor bank. It is
mainly used on elements with external fuses but can also be used on elements with
IEC 61850 IEC 60617
identification identification
VDCPTOV -
1MRK 511 401-UUS A
(Equation 95)
SEMOD153860-1 v2
SEMOD167723-2 v2
ANSI/IEEE C37.2
device number
60
SEMOD153893-5 v3
Bay control REC670 2.2 ANSI
Application manual