GE G30 - Synchrocheck; Tracking Frequency; Frequency Rate of Change

6-22 G30 Generator Protection System GE Multilin
6.3 METERING 6 ACTUAL VALUES
6
(EQ 6.3)
The harmonics are a percentage of the fundamental signal obtained as a ratio of harmonic amplitude to fundamental ampli-
tude multiplied by 100%. The total harmonic distortion (THD) is the ratio of the total harmonic content to the fundamental:
(EQ 6.4)
Voltage harmonics are calculated only for Wye connected phase VTs. Ensure the SYSTEM SETUP  AC INPUTS 
VOLTAGE BANK F5  PHASE VT XX CONNECTION setting is “Wye” to enable voltage harmonics metering.
6.3.4 SYNCHROCHECK
PATH: ACTUAL VALUES  METERING  SYNCHROCHECK  SYNCHROCHECK 1(4)
If a synchrocheck function setting is "Disabled", the corresponding actual values menu item is not displayed.
6.3.5 TRACKING FREQUENCY
PATH: ACTUAL VALUES  METERING  TRACKING FREQUENCY
The tracking frequency is displayed here. The frequency is tracked based on the selection of the reference source with the
FREQUENCY AND PHASE REFERENCE setting in the SETTINGS  SYSTEM SETUP  POWER SYSTEM menu. See the Power
System section of chapter 5 for details.
6.3.6 FREQUENCY RATE OF CHANGE
PATH: ACTUAL VALUES  METERING  FREQUENCY RATE OF CHANGE
The metered frequency rate of change for the frequency rate of change elements is shown here.
 SYNCHROCHECK 1

SYNCHROCHECK 1 DELTA
VOLT: 0.000 V
MESSAGE
SYNCHROCHECK 1 DELTA
PHASE: 0.0°
MESSAGE
SYNCHROCHECK 1 DELTA
FREQ: 0.00 Hz
 TRACKING FREQUENCY

TRACKING FREQUENCY:
60.00 Hz
 FREQUENCY RATE
 OF CHANGE
FREQUENCY RATE OF
CHANGE 1: 0.00 Hz/s
MESSAGE
FREQUENCY RATE OF
CHANGE 2: 0.00 Hz/s
MESSAGE
FREQUENCY RATE OF
CHANGE 3: 0.00 Hz/s
MESSAGE
FREQUENCY RATE OF
CHANGE 4: 0.00 Hz/s
F
real
mh,()
2
N
----
fm k–() h ω
0
tk()⋅⋅()cos⋅()
k

=
F
imag
mh,()
2
N
----
fm k–()h ω
0
tk()⋅⋅()sin⋅()
k

=
F
ampl
mh,() F
real
mh,()
2
F
imag
mh,()
2
+=
THD F
2
2
F
3
2
… F
25
2
+++=
NOTE