Technical Data - ABB REG650 Technical Manual

1MRK 502 043-UUS B
9.4.8
9.5
9.5.1
9.5.2
Technical Manual

Technical data

Table 160: OEXPVPH (24) technical data
Function
Pickup value, pickup
Pickup value, alarm
Pickup value, high level
Curve type
Minimum time delay for inverse
function
Alarm time delay
100% Stator ground fault protection, 3rd harmonic
based STEFPHIZ (59THD)
Identification
Function description
100% Stator ground fault protection,
3rd harmonic based
Functionality
Stator ground fault is a fault type having relatively high fault rate. The generator
systems normally have high impedance grounding, that is, grounding via a neutral
point resistor. This resistor is normally dimensioned to give an ground fault current in
the range 3 – 15 A at a solid ground-fault directly at the generator high voltage
terminal. The relatively small ground fault currents give much less thermal and
mechanical stress on the generator, compared to the short circuit case, which is
between conductors of two phases. Anyhow, the ground faults in the generator have to
be detected and the generator has to be tripped, even if longer fault time compared to
internal short circuits, can be allowed.
Range or value
VBase /f
(100–180)% of ( )
n
(50–120)% of pickup level
(100–200)% of ( VBase /f )
n
IEEE
×
(0.18 TD )
=
IEEE t :
- 2
( M 1)
(Equation 90)
EQUATION1645 V1 EN
where M = (E/f)/(Vn/fn)
(0.000–60.000) s
(0.000–60.000) s
IEC 61850 IEC 60617
identification identification
STEFPHIZ
Section 9
Voltage protection
Accuracy
± 0.5% of V
± 0.5% of V at V ≤ V
n n
± 0.5% of V at V > V
n
± 0.5% of V
± 5% + 40 ms
± 0.5% ± 25 ms
± 0.5% ± 25 ms
ANSI/IEEE C37.2
device number
- 59THD
281