GE UR series

GE Multilin L60 Line Phase Comparison System 5-143
5 SETTINGS 5.5 GROUPED ELEMENTS
5
Figure 5–71: GROUND DISTANCE ZONES 2 AND HIGHER SCHEME LOGIC
GROUND DIRECTIONAL SUPERVISION:
A dual (zero-sequence and negative-sequence) memory-polarized directional supervision applied to the ground distance
protection elements has been shown to give good directional integrity. However, a reverse double-line-to-ground fault can
lead to a maloperation of the ground element in a sound phase if the zone reach setting is increased to cover high resis-
tance faults.
Ground distance zones 2 and higher use an additional ground directional supervision to enhance directional integrity. The
element’s directional characteristic angle is used as a maximum torque angle together with a 90° limit angle.
The supervision is biased toward operation in order to avoid compromising the sensitivity of ground distance elements at
low signal levels. Otherwise, the reverse fault condition that generates concern will have high polarizing levels so that a cor-
rect reverse fault decision can be reliably made.
The supervision for zones 2 and 3 is removed during open pole conditions.
837011AG.CDR
AND
AND
AND
OR
Quadrilateral
characteristic
only
AND
OR
MEMORY
V_1>0.80pu
I_1 > 0.025 pu
SETTING
Enabled = 1
Disabled = 0
GND DIST Z2 FUNCTION
SETTING
Off=0
GND DIST Z2 BLK
SETTING
IA-IB
IB-IC
DISTANCE SOURCE
IC-IA
VAG-VBG
VBG-VCG
VCG-VAG
VAB
VBC
VCA
V_1
I_1
Wye
VTs
Delta
VTs
SETTINGS
GND DIST Z2 ZOM/Z1 ANG
RUN
A ELEMENT
RUN
B ELEMENT
RUN
C ELEMENT
GND DIST Z2 POL CURRENT
GND DIST Z2 NON-HOMGEN ANG
GND DIST Z2 COMP LIMIT
GND DIST Z2 DIR RCA
GND DIST DIR COMP LIMITZ2
GND DIST Z2 VOLT LEVEL
GND DIST Z2 QUAD RGT BLD
GND DIST Z2 QUAD RGT BLD RCA
GND DIST Z2 QUAD LFT BLD
GND DIST Z2 QUAD LFT BLD RCA
TIMER
1 cycle
1 cycle
SETTING
GND DIST Z2 SUPV
RUN
|IN|>Pickup
FLEXLOGIC OPERANDS
GND DIST Z2 PKP AB
GND DIST DPO AZ2
FLEXLOGIC OPERANDS
GND DIST PKP BZ2
GND DIST DPO BZ2
FLEXLOGIC OPERANDS
GND DIST PKP CZ2
GND DIST DPO CZ2
FLEXLOGIC OPERAND
GND DIST PKPZ2
FLEXLOGIC OPERANDS
OPEN POLE OP AФ
OPEN POLE OP BФ
OPEN POLE OP CФ
D60, L60, and L90 only
GND DIST Z2 SUPN IN
GND DIST Z2 DIR SUPN
FLEXLOGIC OPERAND
OPEN POLE OP **
IN
I_2
I_0
GND DIST Z2 REV REACH
GND DIST Z2 REV REACH RCA
GND DIST Z2 REACH
GND DIST Z2 RCA
GND DIST Z2 ZOM/Z1 MAG
GND DIST Z2 Z0/Z2 ANG
GND DIST Z2 Z0/Z2 MAG
GND DIST Z2 SHAPE
GND DIST Z2 DIR
OR
** D60, L60, and L90 only