Monitored Data; Operation Principle - ABB REG650 Technical Manual

Section 9
Voltage protection
Table 181: STEFPHIZ Non group settings (basic)
Name
GlobalBaseSel
TVoltType
9.5.6
9.5.7
288
Values (Range) Unit
1 - 6 -
NoVoltage -
ResidualVoltage
AllThreePhases
PhaseL1
PhaseL2
PhaseL3

Monitored data

Table 182: STEFPHIZ Monitored data
Name
UT3
UN3
E3
ANGLE
DU3
BU3
UN

Operation principle

The protection is a combination of the 95% fundamental frequency earth fault
protection and the100% Stator earth fault protection, 3
(STEFPHIZ). The 3
rd
3 harmonic voltage generated by the generator itself. To assure reliable function of
the protection it is necessary that the 3
RMS on VT secondary side.
rd
The 3 harmonic voltage generated by the generator has the same phase angle in the
three phases. It has the characteristic of a zero sequence component. If the generator
is connected to the power system via a block transformer that cannot transform zero
sequence voltages between the voltage levels, the 3
and U in fig 144, in the generator system is not influenced by the external power
3T
system. At normal operation the generator third harmonic voltage characteristic can
be described as in figure 144.
Step Default
1 1
- ResidualVoltage
Type Values (Range)
REAL -
REAL -
REAL -
REAL -
REAL -
REAL -
REAL -
rd
harmonic based 100% stator earth fault protection is using the
rd
harmonic voltage generation is at least 0.8 V
1MRK 502 048-UEN A
Description
Selection of one of the Global Base Value
groups
Used connection type for gen. terminal
voltage transformer
Unit Description
kV Mag. of 3rd harm. voltage
at generator terminal side
kV Mag. of 3rd harm. voltage
at generator neutral side
kV Total induced stator 3rd
harmonic voltage
deg Angle between 3rd
harmonic votage phasors
kV Diff. between 3rd harm.
volt. at both sides of gen.
kV Bias voltage, a part of
UN3
kV Fund. frequency voltage
at generator neutral
rd
harmonic based,
rd
harmonic voltage, that is U
Technical manual
3N