Load-Shedding Inputs And Outputs - ABB RELION 630 Series Product Manual

Power Management
PML630/Compact Load-Shedding Solution
Product version: 1.2.1
Load-shedding blocking behavior in Configuration B
When the fast and slow load-shedding modes become blocked
in the subnetwork connected to the adjacent power network
area in a 2-peer PML630 Configuration B scenario, the adjacent
power network area (subnetwork) goes automatically into the
Configuration A mode. The PML630 device in the unblocked
power network area discards the spinning reserve power from
the peer PML630 device and considers its own grid capacity for
the power balance calculations. Since the subnetworks are not
disconnected physically, the grid 1 or 2 capacity setting can still
be used and kept equal to the spinning reserve power or based
on the capacity of the tie line.
If the load-shedding in 1 or 2 subnetworks (connected to the
adjacent power area networks) in the power network area is
controlled by PML630_2 device becomes blocked in a 3-peer
PML630 device Configuration B scenario, the subnetworks in
the adjacent power network areas controlled by the PML630_1
and the PML630_3 devices go into the Configuration A mode.
However, if an interconnected subnetwork in the PML630_1 or
PML630_3 device becomes blocked, the connected
subnetworks in an adjacent power areas stay in the
Configuration B mode.
Load feeder inhibition
The load feeder inhibition feature is used to prevent the load-
shedding functions from initiating opening commands to the
inhibited load feeder. A load feeder inhibition can be achieved
automatically or manually.
Automatic load feeder inhibition
A load feeder is inhibited automatically for load-shedding under
certain conditions.
• Communication failure between a load feeder 630, 620 or
615 series protection relay or RIO600 IO unit and PML630
• Bad IEC 61850 data quality from a load feeder 630, 620 or
615 series protection relay or RIO600 IO unit
• Load feeder 630, 620 or 615 series protection relay or
RIO600 IO unit in the test mode (also reflected in the IEC
61850 data quality)
• Based on an external input like a load circuit breaker trip
circuit not healthy or in a racked-out condition
Manual load feeder inhibition
Manual load feeder inhibition can be performed from the
PML630 device's local or Web HMI.
Load-shedding enabling and disabling in subnetworks
Load-shedding can be enabled or disabled in a subnetwork.
However, the load-shedding block setting overrides individual
subnetwork settings.
PML630 test mode behavior
The purpose of the test mode is to verify the load-shedding
functionality until the load feeder 630, 620 or 615 series
protection relays or RIO600 units.
ABB
PML630 and load feeder protection relays
When PML630 is put in the test mode from LHMI or WHMI, all
the load-shedding functions are blocked. All the functions need
to unblock to make them work again.
In this mode, the load-shedding command information (sent on
IEC 61850 GOOSE) to the load feeder 630, 620 or 615 series
protection relays or RIO600 units has a set test bit. In addition,
a separate binary input is also sent together. On receipt of the
load-shedding command with a set test bit and/or the
dedicated PML630 device test mode information, the load
feeder protection relay or IO unit blocks the load-shedding
command from reaching the binary output channel.
Peer PML630 devices
When a PML630 device receives the power network
information from another peer PML630 in the test mode, it can
choose to consider the information or reject it.
When the adjacent power area network information is
considered, the recipient PML630 also goes into test mode and
runs in the Configuration B mode. If the load-shedding is
activated by any of the PML630 devices, shedding commands
are not issued to any of the load circuit breakers in the same
power network area or other power network areas.
By rejecting it, the recipient PML630 device's subnetwork goes
into the Configuration A mode until the peer PML630 device's
test status changes to normal mode.
The selection to influence this behavior can be parameterized.

13. Load-shedding inputs and outputs

IEC 61850 GOOSE communication
The fast and slow load-shedding functions in PML630 require a
fixed set of input data from the power source, load feeder 630,
620 or 615 series protection relays and RIO600 units.
• The REG630 or REG615 generator power source
protection relay should be configured to send the active
power, circuit breaker status, circuit breaker service
position and protection trip information. If the generator
power source also needs to be configured for slow
(overload) load-shedding, the 3-phase currents need to be
configured too.
• The RET630 and RET620 grid transformer protection relay
is configured to send the three-phase currents, active
power, circuit breaker status, circuit breaker service
position and protection trip information.
• The REF630 and REF620 grid utility tie feeder power
source or the network circuit breaker protection relay is
configured to send the active power, circuit breaker
status, circuit breaker service position and protection trip
information.
• The REF630 or REM630 or RET630, REF620 or REM620
or RET620 and REF615 or REM615 or RET615 load feeder
1MRS757334 E
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