ABB Relion 650 Series Technical Manual page 248

Section 7
Voltage protection
OV2PTOV (59) can be set to measure phase-to-ground fundamental value, phase-to-phase
fundamental value, phase-to-ground RMS value or phase-to-phase RMS value. The choice of
measuring is done by the parameter
The voltage related settings are made in percent of base voltage which is set in kV phase-to-phase
voltage. OV2PTOV (59) will operate if the voltage gets higher than the set percentage of the set
global base voltage
Vpickup
EQUATION1610 V2 EN-US
and operation for phase-to-phase voltage over:
Vpickup
EQUATION1992 V1 EN-US
7.2.7.1 Measurement principle
All the three voltages are measured continuously, and compared with the set values,
Pickup2 . The parameters OpMode1 and OpMode2 influence the requirements to activate the
PICKUP outputs. Either
the corresponding set point to issue the corresponding PICKUP signal.
To avoid oscillations of the output PICKUP signal, a hysteresis has been included.
7.2.7.2 Time delay
The time delay for step 1 can be either definite time delay (DT) or inverse time overcurrent (TOV).
Step 2 is always definite time delay (DT). For the inverse time delay three different modes are
available:
• inverse curve A
• inverse curve B
• inverse curve C
The type A curve is described as:
TD
t
=
V Vpickup
−
Vpickup
EQUATION1625 V2 EN-US
The type B curve is described as:
242
VBase . This means operation for phase-to-ground voltage over:
(%) VBase kV ( ) / 3
> ⋅
> ×
(%) VBase(kV)
When phase-to-ground voltage measurement is selected the function
automatically introduces division of the base value by the square root of three.
1 out of 3 , 2 out of 3 or 3 out of 3 measured voltages have to be higher than
>
>
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ConnType .
1MRK 506 326-UUS B
(Equation 54)
(Equation 55)
M15330-6 v4
Pickup1 and
M15330-10 v5
(Equation 56)
Line distance protection REL650
Technical manual