Tracking Frequency; Flexelements - GE T35 Instruction Manual

METERING
This menu displays metered values for real, reactive, and apparent power, as well as power factor. The "SRC 1" text is
replaced by the name programmed by the user for the associated source (see
).
SOURCES
When VTs are configured in wye, the T35 calculates power in each phase and three-phase power is measured as
When VTs are configured in delta, the T35 does not calculate power in each phase and three-phase power is measured as
where
S is the apparent power
V , V , V , I , I , I
A B C A B C
V and V are phase-to-phase voltage phasors
AB CB
Î is the conjugate of I
6.4.3.7 Frequency metering
ACTUAL VALUES  METERING  SOURCE SRC 1  FREQUENCY
 FREQUENCY
 SRC 1
The metered frequency values are displayed in this menu. The "SRC 1" text is replaced by the name programmed by the
user for the associated source (see
SOURCE FREQUENCY
6
Clarke transformation of three-phase voltages or currents, auxiliary voltage, or ground current as per source configuration
(see the
SYSTEM SETUP  POWER SYSTEM
frequency measurement is passed through a validation filter that eliminates false readings due to signal distortions and
transients.

6.4.4 Tracking frequency

ACTUAL VALUES  METERING  TRACKING FREQUENCY
 TRACKING FREQUENCY

The tracking frequency displays here. The frequency is tracked based on the selection of the reference source with the
FREQUENCY AND PHASE REFERENCE
System section of chapter 5 for details.

6.4.5 FlexElements

ACTUAL VALUES  METERING  FLEXELEMENTS  FLEXELEMENT 1(16)
 FLEXELEMENT 1

The operating signals for the FlexElements are displayed in pu values using the following definitions of the base units.
6-20
SRC 1 POWER FACTOR

φb:
SRC 1 POWER FACTOR

φc:
S = V
are phase voltage and phase current phasors
SRC 1 FREQUENCY:

0.00 Hz
SETTINGS  SYSTEM SETUP  SIGNAL SOURCES
is measured via software-implemented zero-crossing detection of an AC signal. The signal is either a
settings). The signal used for frequency estimation is low-pass filtered. The final
TRACKING FREQUENCY:

60.00 Hz
setting in the
FLEXELEMENT 1

OpSig:
1.000
1.000
x Î + V x Î + V x Î
A A B B C C
S = V x Î + V x Î
AB A CB C
SETTINGS  SYSTEM SETUP  POWER SYSTEM
0.000
T35 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 6: ACTUAL VALUES
SETTINGS  SYSTEM SETUP  SIGNAL
).
menu. See the Power
Eq. 6-1
Eq. 6-2