ABB RET670 Product Manual page 20

Transformer protection RET670
Customized
Product version: 1.2
supervised. Enhanced security means that the
command is evaluated with an additional
supervision of the status value of the control
object. The command security with enhanced
security is always terminated by a
CommandTermination service primitive.
Control operation can be performed from the
local HMI under authority control if so defined.
Voltage control TR1ATCC, TR8ATCC, TCMYLTC
and TCLYLTC
The voltage control functions, Automatic voltage
control for tap changer, single control TR1ATCC,
Automatic voltage control for tap changer ,
parallel control TR8ATCC and Tap changer
control and supervision, 6 binary inputs
TCMYLTC as well as Tap changer control and
supervision, 32 binary inputs TCLYLTC are used
for control of power transformers with a on-load
tap changer. The functions provide automatic
regulation of the voltage on the secondary side of
transformers or alternatively on a load point
further out in the network.
Control of a single transformer, as well as control
of up to eight transformers in parallel is possible.
For parallel control of power transformers, three
alternative methods are available, the master-
follower method, the circulating current method
and the reverse reactance method. The two
former methods require exchange of information
between the parallel transformers and this is
provided for within IEC61850-8-1.
Voltage control includes many extra features such
as possibility of to avoid simultaneous tapping of
parallel transformers, hot stand by regulation of a
transformer in a group which regulates it to a
correct tap position even though the LV CB is
open, compensation for a possible capacitor bank
on the LV side bay of a transformer, extensive tap
changer monitoring including contact wear and
hunting detection, monitoring of the power flow in
the transformer so that for example, the voltage
control can be blocked if the power reverses etc.
Logic rotating switch for function selection and
LHMI presentation SLGGIO
The logic rotating switch for function selection
and LHMI presentation (SLGGIO) (or the selector
switch function block) is used to get a selector
switch functionality similar to the one provided by
a hardware selector switch. Hardware selector
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1MRK 504 117-BEN D
switches are used extensively by utilities, in order
to have different functions operating on pre-set
values. Hardware switches are however sources
for maintenance issues, lower system reliability
and an extended purchase portfolio. The logic
selector switches eliminate all these problems.
Selector mini switch VSGGIO
The Selector mini switch VSGGIO function block
is a multipurpose function used for a variety of
applications, as a general purpose switch.
VSGGIO can be controlled from the menu or from
a symbol on the single line diagram (SLD) on the
local HMI.
IEC 61850 generic communication I/O functions
DPGGIO
The IEC 61850 generic communication I/O
functions (DPGGIO) function block is used to
send double indications to other systems or
equipment in the substation. It is especially used
in the interlocking and reservation station-wide
logics.
Single point generic control 8 signals SPC8GGIO
The Single point generic control 8 signals
(SPC8GGIO) function block is a collection of 8
single point commands, designed to bring in
commands from REMOTE (SCADA) to those parts
of the logic configuration that do not need
extensive command receiving functionality (for
example, SCSWI). In this way, simple commands
can be sent directly to the IED outputs, without
confirmation. Confirmation (status) of the result of
the commands is supposed to be achieved by
other means, such as binary inputs and SPGGIO
function blocks. The commands can be pulsed or
steady.
AutomationBits, command function for DNP3.0
AUTOBITS
AutomationBits function for DNP3 (AUTOBITS) is
used within PCM600 to get into the configuration
of the commands coming through the DNP3
protocol. The AUTOBITS function plays the same
role as functions GOOSEBINRCV (for IEC 61850)
and MULTICMDRCV (for LON).
Single command, 16 signals
The IEDs can receive commands either from a
substation automation system or from the local
HMI. The command function block has outputs
that can be used, for example, to control high
ABB