Application - ABB RELION 650 Series Product Manual

Transformer protection RET650 2.1 IEC

1. Application

The RET650 provides fast and selective protection,
monitoring and control functions for two- and three-
winding transformers, autotransformers, generator-
transformer units and shunt reactors. The IED is
designed to operate correctly over a wide frequency
range in order to accommodate power system frequency
variations during disturbances and generator startup
and shutdown. Apparatus control for 3 circuit breakers
is included.
A fast differential protection function with built-in
transformer ratio matching and vector group
compensation makes this IED the ideal solution even for
the most demanding applications. Since RET650 has
very low requirements on the main CTs, no interposing
CTs are required. The differential protection function is
provided with 2nd harmonic and waveform-blocking
restraint features to avoid tripping for magnetizing
inrush current, and 5th harmonic restraint to avoid
tripping for overexcitation.
The differential function offers a high sensitivity for
low-level internal faults. The unique and innovative
sensitive differential protection feature of the RET650
provides the best possible coverage for internal turn-to-
turn winding faults, based on the theory of symmetrical
components.
A low impedance restricted earth-fault protection
function is available as a complimentary sensitive and
fast main protection against winding earth faults. This
function includes a directional zero-sequence current
criterion for additional security.
Tripping from pressure relief/Buchholz and temperature
devices can be implemented through the IED's binary
inputs, where trip signal conditioning can be performed
(pulsing, lockout, additional logics, etc). The binary
inputs are thoroughly stabilized against disturbances in
order to prevent incorrect operations due to for
example DC system capacitive discharges or DC earth
faults.
Versatile phase, earth and zero sequence overcurrent
functions with directional capability provide further
ABB
GUID-EB939A4F-1C88-4EB1-A217-571FEF72AC7B v2
alternative backup protections. Thermal overload with
two time-constants and breaker failure protection is
also available.
A built-in disturbance and event recorder provides
valuable data to the user about status and operation for
post-fault disturbance analysis.
One pre-configured package has been defined for the
following application:
• Three-winding transformer in single breaker
arrangements (A05)
The package is configured and ready for direct use.
Analog and control circuits have been predefined and
other signals need to be applied as required for each
application. The pre-configured IED can be changed and
adapted to suit specific applications with the graphical
configuration tool.
Forcing of binary inputs and outputs is a convenient way
to test wiring in substations as well as testing
configuration logic in the IEDs. Basically it means that all
binary inputs and outputs on the IED I/O modules (BOM,
BIM and IOM) can be forced to arbitrary values.
Central Account Management is an authentication
infrastructure that offers a secure solution for enforcing
access control to IEDs and other systems within a
substation. This incorporates management of user
accounts, roles and certificates and the distribution of
such, a procedure completely transparent to the user.
The Flexible Product Naming allows the customer to use
an IED-vendor independent 61850 model of the IED. This
customer model will be used as the IEC 61850 data
model, but all other aspects of the IED will remain
unchanged (e.g., names on the local HMI and names in
the tools). This offers significant flexibility to adapt the
IED to the customers system and standard solution
Description of A05
Three-winding transformer in single breaker
arrangements.
1MRK 504 161-BEN C
Issued: March 2019
Revision: C
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