ABB REB500 Distributed busbar protection
Distributed busbar protection REB500including line and transformer protection
Main features • Low-impedance busbar protection
• Stub and T-zone protection
• High functional reliability due to two inde pendent measurement criteria:
- stabilized differential current algorithm
- directional current comparison algorithm
• Phase-by-phase measurement
• Reduced CT performance requirements
• High through-fault stability even in case of CT saturation
• Full solid-state busbar replica
• No switching of CT circuits
• Only one hardware version for
- 1 and 5 A rated currents
- all auxiliary supply voltages between
48 V DC and 250 V DC
- nominal frequencies of 50, 60 and 16.7 Hz
• Short tripping times independent of the
plant’s size or configuration
• Centralized layout: Installation of hardware
in one or several cubicles
• Distributed layout: Bay units distributed
and, in the case of location close to the
feeders, with short connections to CTs, iso lators, circuit breakers, etc.
• Connections between bay units and central
unit by fiber-optic cables
- maximum permissible length 1200 m
- for distributed and centralized layout
• fiber-optic connections mean interference proof data transfer even close to HV power
cables
• Replacement of existing busbar protection
schemes can be accomplished without re strictions (centralized layout) in the case of
substation extensions e.g. by a mixture of
centralized and distributed layout
• Easily extensible
• User-friendly, PC-based human machine
interface (HMI)
• Fully numerical signal processing
• Comprehensive self-supervision
• Binary logic and timer in the bay unit
• Integrated event recording
• Integrated disturbance recording for power
system currents
• A minimum of spare parts needed due to
standardization and a low number of vary ing units
• Communication facilities for substation
monitoring and control systems via
IEC 61850-8-1, IEC 60870-5-103 and LON
• IEC 62439 standard redundant station bus
communication
• IEC 61850-9-2 LE process bus communi cation
• Cyber security to support
- User Access Management
- User Activity Logging
Options
• Breaker failure protection (also separately
operable without busbar protection)
• End fault protection
• Definite time overcurrent protection
• Breaker pole discrepancy
• Current and voltage release criteria
• Disturbance recording for power system
voltages
• Separate I0 measurement for impedance grounded networks
• Communication with substation monitoring
and control system (IEC 61850-8-1 /
IEC 60870-5-103 / LON)
• Internal user-friendly human machine inter face with display
• Redundant power supply for central units
and/or bay units
Additional
main features
REB500sys combines the well-proven numer ical busbar and breaker failure protection
REB500 of ABB with Main 2 or back-up pro tection for line or transformer feeders. The
Main 2 / Group 1 or back-up protection is
based on the well-proven protection function
library of ABB line and transformer protection
for 50, 60 and 16.7 Hz.
Main 2 / back-up bay protection
• Definite and inverse time over- and under current protection
• Directional overcurrent definite and inverse
time protection
• Inverse time earth fault overcurrent protec tion
• Definite time over- and undervoltage pro tection

Distributed busbar protection REB500
including line and transformer protection
• Three-phase current and three-phase volt age plausibility
Main 2 / back-up bay protection:
Line protection
• High-speed distance protection
• Directional sensitive earth fault protection
for grounded systems against high resis tive faults in solidly grounded networks
• Directional sensitive earth fault protection
for ungrounded or compensated systems
• Autoreclosure for
- single-pole / three-pole reclosure
- up to four reclosure sequences
• Synchrocheck with
- measurement of amplitudes, phase
angles and frequency of two voltage
vectors
- checks for dead line, dead bus, dead
line and bus
Group 1 / back-up bay protection:
Transformer protection
• High-speed transformer differential protec tion for 2- and 3-winding and auto-trans formers
• Thermal overload
• Peak value over- and undercurrent protec tion
• Peak value over- and undervoltage protec tion
• Overfluxing protection
• Rate of change frequency protection
• Frequency protection
• Independent T-Zone protection with trans former differential protection
• Power protection
Application REB500
The numerical busbar protection REB500 is
designed for the high-speed, selective protec tion of MV, HV and EHV busbar installations
at a nominal frequency of 50, 60 and 16.7 Hz.
The structure of both hardware and software
is modular enabling the protection to be easily
configured to suit the layout of the primary
system.
The flexibility of the system enables all config urations of busbars from single busbars to
quadruple busbars with transfer buses, ring
busbars and 1½ breaker schemes to be pro tected.
In 1½ breaker schemes the busbars and the
entire diameters, including Stub/T-Zone can
be protected. An integrated tripping scheme
allows to save external logics as well as wir ing.
The capacity is sufficient for up to 60 feeders
(bay units) and a total of 32 busbar zones.
The numerical busbar protection REB500
detects all phase and earth faults in solidly
grounded and resistive-grounded power sys tems and phase faults in ungrounded systems
and systems with Petersen coils.
The main CTs supplying the currents to the
busbar protection have to fulfil only modest
performance requirements (see page 18). The
protection operates discriminatively for all
faults inside the zone of protection and
remains reliably stable for all faults outside the
zone of protection.
REB500sys
The REB500sys is foreseen in MV, HV and
EHV substations with nominal frequencies of
16.7, 50 Hz or 60 Hz to protect the busbars
and their feeders. The bay protection func tions included in REB500sys are used as
Main 2 / Group 1 - or back-up protection.
The system REB500sys is foreseen for all sin gle or double busbar configurations
(Line vari ants L-V1 to L-V7 and Transformer variant T V1 to T-V4). In 1½ breaker configurations,
variant L-V5 can be used for the bay level
functions autoreclosure and synchrocheck.
The capacity is sufficient for up to 60 feeders
(bay units) and a total of 32 busbar zones.
The REB500sys detects all bus faults in sol idly and low resistive-grounded power sys tems,
all kind of phase faults in ungrounded
and compensated power systems as well as
feeder faults in solidly, low resistive-grounded,
compensated and ungrounded power sys tems.
The protection operates selectively for all
faults inside the zone of protection and
remains reliably stable for all faults outside the
zone of protection.
REB500sys is perfectly suited for retrofit con cepts and stepwise upgrades. The bay unit is
used as a stand-alone unit for bay protection
functions (e.g. line protection, autoreclosure
and synchrocheck or 2- and 3 winding trans former protection or autonomous T-zone pro tection).
The central unit can be added at a
later stage for full busbar and breaker failure
protection functionality.