ABB RES670 Technical Manual page 298

Section 9
Voltage protection
292
where:
Vpickup Set value for step 1 and step 2
>
V Measured voltage
The type B curve is described as:
TD 480
⋅
t
= +
V Vpickup
− >
32 0 5 .
⋅ −
Vpickup
>
ANSIEQUATION2287 V3 EN-US
The type C curve is described as:
⋅
TD 480
= +
t
− >
V Vpickup
⋅ −
32 0 5 .
>
Vpickup
ANSIEQUATION2288 V2 EN-US
The customer programmable curve is defined by the below equation, where A, B, C, D,
k and p are settings:
×
TD A
=
t
æ ö
-
V Vpickup
× -
ç ÷
B C
è ø
Vpickup
EQUATION1616 V1 EN-US
When the denominator in the expression is equal to zero the time delay will be infinity.
There will be an undesired discontinuity. Therefore, a tuning parameter CrvSatn is set
to compensate for this phenomenon. In the voltage interval Vpickup up to Vpickup ·
(1.0 + CrvSatn/100) the used voltage will be: Vpickup · (1.0 + CrvSatn/100). If the
programmable curve is used this parameter must be calculated so that:
CrvSatn
× - >
B C 0
100
EQUATION1435 V1 EN-US
The highest phase (or phase-to-phase) voltage is always used for the inverse time delay
integration, see figure 97. The details of the different inverse time characteristics are
shown in section "Inverse
0 035 .
0 035 .
+
D
P
characteristics".
1MRK 511 408-UUS A
Phasor measurement unit RES670 2.2 ANSI
Technical manual
(Equation 57)
(Equation 58)
(Equation 59)
(Equation 60)