Automation Features - GE D90 Plus Instruction Manual

DEVICE OVERVIEW
Autoreclose
Breaker failure
Multi-breaker configurations
Single-pole tripping

Automation features

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• Instantaneous and timed overcurrent elements for phase, neutral, ground, and
negative-sequence protection.
• Directional supervision is available for phase, neutral, and negative-sequence
elements.
• Time overcurrent elements can individually be set to use IEEE, IEC, or custom
FlexCurves™.
Plus
The D90 provides multi-shot autoreclosing for single-pole or three-pole autoreclose on
all types of faults with independently programmable dead times for each shot.
Autoreclosing also can be dynamically blocked by user programmable logic. Four different
autoreclose modes are available enabling the users to select the reclosing mode of their
practice.
Plus
The D90 can be used to carry out fully independent breaker failure protection over the
breakers associated to the line when connected to a substation with a breaker-and-a-half
or ring bus arrangement. The D90
inputs and outputs, and elements to perform two independent breaker failure functions.
Plus
The D90 supports multi-breaker busbar configurations such as breaker-and-a-half or
ring bus arrangements, providing dual breaker autoreclose, dual synchrocheck elements,
and dual independent breaker failure elements.
Figure 10: Breaker-and-a-half configuration example
Plus
The D90 relay uses an advanced phase selection algorithm that provides fast and
accurate fault type identification even under weak-infeed conditions. The pilot schemes
for single pole tripping offer an option to send the permissive/ blocking signal using one,
two or four bits of information. This allows sharing more information between the terminal
relays and improving the accuracy of single-pole tripping on cross-country faults. A
convenient trip function is built-in to coordinate actions of the key elements of the single-
pole tripping package.
A separate automation engine with powerful Boolean and math functions allows the user
to easily engineer complex custom automation schemes. This includes advanced
interlocking schemes, remedial action schemes, and advanced load shedding schemes.
Plus
provides the required current source inputs, digital
PLUS
D90 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 2: PRODUCT DESCRIPTION