ABB Relion REG670, Техническое руководство

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• 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.
14.3.2 Operation principle
A bay can handle, for example a power line, a transformer, a reactor, or a capacitor
bank. The different primary apparatuses within the bay can be controlled via the
apparatus control function directly by the operator or indirectly by automatic
sequences.
Because a primary apparatus can be allocated to many functions within a Substation
Automation system, the object-oriented approach with a function block that handles
the interaction and status of each process object ensures consistency in the process
information used by higher-level control functions.
Primary apparatuses such as breakers and disconnectors are controlled and supervised
by one function block (SCSWI) each. Because the number and type of signals used for
the control of a breaker respectively a disconnector are almost the same, the same
function block type is used to handle these two types of apparatuses.
The SCSWI function block is connected either to an SXCBR function block (for
circuit breakers) or to an SXSWI function block (for disconnectors and earthing
switches). The physical process in the switchyard is connected to these two function
blocks via binary inputs and outputs.
1MRK502052-UEN B
Section 14
Control
705
Technical manual