at least one side dead to ensure that closing can be
done safely.
SESRSYN function includes a built-in voltage selection
scheme for double bus and 1½ breaker or ring busbar
arrangements.
Manual closing as well as automatic reclosing can be
checked by the function and can have different settings.
For systems, which can run asynchronously, a
synchronizing feature is also provided. The main
purpose of the synchronizing feature is to provide
controlled closing of circuit breakers when two
asynchronous systems are in phase and can be
connected. The synchronizing feature evaluates voltage
difference, phase angle difference, slip frequency and
frequency rate of change before issuing a controlled
closing of the circuit breaker. Breaker closing time is a
setting.
However this function can not be used to automatically
synchronize the generator to the network.
Apparatus control APC
M13444-3 v16
The apparatus control functions are used for control and
supervision of circuit breakers, disconnectors and
earthing switches within a bay. Permission to operate is
given after evaluation of conditions from other
functions such as interlocking, synchrocheck, operator
place selection and external or internal blockings.
Apparatus control features:
• Select-Execute principle to give high reliability
• Selection function to prevent simultaneous operation
• Selection and supervision of operator place
• Command supervision
• Block/deblock of operation
• Block/deblock of updating of position indications
• Substitution of position and quality indications
• Overriding of interlocking functions
• Overriding of synchrocheck
• Operation counter
• Suppression of mid position
Two types of command models can be used:
• Direct with normal security
• SBO (Select-Before-Operate) with enhanced security
Normal security means that only the command is
evaluated and the resulting position is not supervised.
Enhanced security means that the command is
evaluated with an additional supervision of the status
value of the control object. The command sequence with
enhanced security is always terminated by a
CommandTermination service primitive and an
AddCause telling if the command was successful or if
something went wrong.
Control operation can be performed from the local HMI
with authority control if so defined.
Interlocking
M13531-3 v4
The interlocking function blocks the possibility to
operate primary switching devices, for instance when a
disconnector is under load, in order to prevent material
damage and/or accidental human injury.
Each apparatus control function has interlocking
modules included for different switchyard
arrangements, where each function handles interlocking
of one bay. The interlocking function is distributed to
each IED and is not dependent on any central function.
For the station-wide interlocking, the IEDs communicate
via the system-wide interbay bus (IEC 61850-8-1) or by
using hard wired binary inputs/outputs. The
interlocking conditions depend on the circuit
configuration and apparatus position status at any
given time.
For easy and safe implementation of the interlocking
function, the IED is delivered with standardized and
tested software interlocking modules containing logic
for the interlocking conditions. The interlocking
conditions can be altered, to meet the customer’s
specific requirements, by adding configurable logic by
means of the graphical configuration tool.
Switch controller SCSWI
M13486-3 v10
The Switch controller (SCSWI) initializes and supervises
all functions to properly select and operate switching
primary apparatuses. The Switch controller may handle
and operate on one multi-phase device or up to three
one-phase devices.
Circuit breaker SXCBR
M13489-3 v6
The purpose of Circuit breaker (SXCBR) is to provide the
actual status of positions and to perform the control
operations, that is, pass all the commands to primary
apparatuses in the form of circuit breakers via binary
output boards and to supervise the switching operation
and position.
Circuit switch SXSWI
M16492-3 v6
The purpose of Circuit switch (SXSWI) function is to
provide the actual status of positions and to perform
the control operations, that is, pass all the commands to
primary apparatuses in the form of disconnectors or
earthing switches via binary output boards and to
supervise the switching operation and position.
Reservation function QCRSV
M13506-3 v5
The purpose of the reservation (QCRSV) function is
primarily to transfer interlocking information between
Generator protection REG670
1MRK 502 074-BEN M
Hitachi Power Grids 37
© Copyright 2017 Hitachi Power Grids. All rights reserved
To Next Page
Loading...
