GE D30 series, Инструкция по эксплуатации

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5-204 D30 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
GROUPED ELEMENTS CHAPTER 5: SETTINGS
5
The ground mho distance function uses a dynamic 100% memory-polarized mho characteristic with additional reactance,
directional, current, and phase selection supervising characteristics. The ground quadrilateral distance function is
composed of a reactance characteristic, right and left blinders, and 100% memory-polarized directional, overcurrent, and
phase selection supervising characteristics.
When set to non-directional, the mho function becomes an offset mho with the reverse reach controlled independently
from the forward reach, and all the directional characteristics removed. When set to non-directional, the quadrilateral
function applies a reactance line in the reverse direction instead of the directional comparators.
The reactance supervision for the mho function uses the zero-sequence current for polarization. The reactance line of the
quadrilateral function uses either zero-sequence or negative-sequence current as a polarizing quantity. The selection is
controlled by a user setting and depends on the degree of non-homogeneity of the zero-sequence and negative-sequence
equivalent networks.
The directional supervision uses memory voltage as polarizing quantity and both zero- and negative-sequence currents as
operating quantities.
The phase selection supervision restrains the ground elements during double-line-to-ground faults as they, by the
principles of distance relaying, can be inaccurate in such conditions. Ground distance zones 1 and higher apply additional
zero-sequence directional supervision.
Each ground distance zone is configured individually through its own setting menu. All of the settings can be modified
independently for each of the zones except:
•
The
SIGNAL SOURCE
setting (common for both phase and ground elements for all zones as entered under the
SETTINGS
 GROUPED ELEMENTS  SETTING GROUP 1(6)  DISTANCE
menu)
• The
MEMORY DURATION
setting (common for both phase and ground elements for all zones as entered under the
SETTINGS  GROUPED ELEMENTS  SETTING GROUP 1(6)  DISTANCE
menu)
The common distance settings noted at the start of this section must be properly chosen for correct operation of the
ground distance elements.
Although all ground distance zones can be used as either instantaneous elements (pickup [
PKP
] and dropout [
DPO
]
FlexLogic signals) or time-delayed elements (operate [
OP
] FlexLogic signals), only zone 1 is intended for the instantaneous
under-reaching tripping mode.
GND DIST Z1 DIR
— All ground distance zones are reversible. The forward direction is defined by the
GND DIST Z1 RCA
setting
and the reverse direction is shifted by 180° from that angle. The non-directional zone spans between the forward reach
impedance defined by the
GND DIST Z1 REACH
and
GND DIST Z1 RCA
settings, and the reverse reach impedance defined by
the
GND DIST Z1 REV REACH
and
GND DIST Z1 REV REACH RCA
settings.
GND DIST Z1 SHAPE
— This setting selects the shape of the ground distance characteristic between the mho and
quadrilateral characteristics. The selection is available on a per-zone basis.
The figures show the directional and non-directional quadrilateral ground distance characteristics. The directional and
non-directional mho ground distance characteristics are the same as those shown for the phase distance element in the
previous section.

GND DIST Z1 BLK:
Off
Range: FlexLogic operand

GND DIST Z1
TARGET: Self-reset
Range: Self-reset, Latched, Disabled

GND DIST Z1
EVENTS: Disabled
Range: Disabled, Enabled
Ensure that the
PHASE VT SECONDARY VOLTAGE
(see the
SETTINGS

SYSTEM SETUP

AC INPUTS

VOLTAGE BANK
menu) is set correctly to prevent improper operation of associated memory action.