Alstom MiCOM P846, Technical Manual

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P846/EN FD/D Firmware Design
(FD) 9-12
MiCOM P846
P0128ENa
Disturbance
recorder task
Fourier signal
processing
Protection
algorithms
Protection & Control
Software
Programable &
fixed scheme logic
Measurements and event, fault
& disturbance records
System services software
Relay hardware
Event, fault,
disturbance,
maintenance record
logging
Front panel
interface - LCD &
keypad
Settings
database
Remote
communications
interface -
IEC60870-5-103
Platform Software
Supervisor task
Protection & control settings
Sample data & digital
logic inputs
Control of interfaces to keypad, LCD,
LEDs, front & rear comms ports.
Self-checking maintenance records
Sampling function -
copies samples into
2 cycle buffer
Remote
communications
interface - Modbus
Local & Remote
communications
interface - Courier
Protection
task
Control of output contacts and
programmable LEDs
Figure 4: Relay software structure
1.4.1 Real-time operating system
The software is split into tasks; the real-time operating system is used to schedule the
processing of the tasks to ensure that they are processed in the time available and in the
desired order of priority. The operating system is also responsible in part for controlling the
communication between the software tasks through the use of operating system messages.
FD
1.4.2 System services software
As shown in Figure 4, the system services software provides the interface between the
relay’s hardware and the higher-level functionality of the platform software and the protection
& control software. For example, the system services software provides drivers for items
such as the LCD display, the keypad and the remote communication ports, and controls the
boot of the processor and downloading of the processor code into SRAM from flash EPROM
at power up.
1.4.3 Platform software
The platform software has three main functions:
•
To control the logging of records that are generated by the protection software, including
alarms and event, fault, and maintenance records.
•
To store and maintain a database of all of the relay’s settings in non-volatile memory.
•
To provide the internal interface between the settings database and each of the relay’s
user interfaces, i.e. the front panel interface and the front and rear communication ports,
using whichever communication protocol has been specified (Courier or DNP3.0).