VGB POWERTECH 11 (2019)

Digital nuclear security level DCS main and auxiliary data distribution based on NASPIC platform VGB PowerTech 11 l 2019
Field sensor
ECP/BUP
drive system. The TU is a data transmission
unit. GW is a communication isolation
unit. ACM is a priority selection unit.
Field control
station
PIPS
SignaI
processing
mudule
Drive
control
module
Switch cabinet
Actuator
Safety display
station
Transmission
station
lE
communication
NC
communication
Fig. 1. NASPIC platform basic architecture diagram.
NASPIC Platform
1E NC
Hard wiring
Maintenance
network
Gateway station
Engineer station
Electrical
isolation
Boundary
NC
system
1E
NC
Research on main and auxiliary data
distribution
Main and auxiliary data definition
In the digital security level DCS system of
nuclear power plant, the data involved in
the implementation of shutdown protection
and dedicated safety facility drive
functions are important information and
need to be processed first. According to the
importance of the transmitted data information,
the data used to perform the shutdown
protection and dedicated safety facility
driver functions are defined as the main
function data, and the related data used to
display, alarm and maintain are defined as
the auxiliary function data. The main function
data of security level DCS system in
executing security function shall not be ad-
tion conditions, and drives corresponding
security functions to make the plant shut
down safely and maintain safe state. This
ensures the safety of reactor, nuclear power
plant equipment, personnel and environment
in case of accident. According to
the requirement of Engineering application,
NASPIC platform can be used to construct
digital security level instrument and
control system for nuclear power plants
with different reactor types (such as
AP1000, Hualong 1, M310) and different
architectures.
IP IIP IIIP
Security level DCS architecture
This paper is based on the digital security
level DCS architecture of China Engineering
Test Reactor, as shown in F i g u r e 2 .
The security level DCS architecture adopts
a three-channel redundant structure,
which consists of three protection groups
(protection group I, protection group II
and protection group III) and two logic series
(logic series A and logic series B). The
signal acquisition and logic processing related
to emergency shutdown system are
implemented in three protection groups.
The functions of the dedicated safety facility
drive system are realised by the protection
group and logic series.
Among them, IP, IIP and IIIP represent
three redundant protection channels;
PIPS-1, PIPS-2 and PIPS-3 represent three
redundant protection channels’ preprocessing
units; RPC-1, RPC-2 and RPC-3 represent
three redundant protection channels’
protection processing units; TU-1,
TU-2 and TU-3 represent three redundant
protection channels’ signal transmission
units; ESFAC-A1 and ESFAC-A2 represent
two subgroups of dedicated security facility
driver units of logical series A, which
carry out 1oo2 decision output; ESFAC-B1
and ESFAC-B2 represent two subgroups of
TRAIN A
dedicated security facility driver systems of
logical series B, which carry out 1oo2 decision
output; ACM-A and ACM-B represent
priority management units of two logical
series; GW-A and GW-B represent the gateway
units of two logical series.
By studying the digital security level DCS
architecture of a domestic engineering test
reactor, it can be found that each protection
group corresponds to one protection
group TU transmission station, and each
logic series corresponds to one logic series
TU transmission station.
Note: PIPS is a signal preprocessing system.
RPC is a reactor shutdown logic processing
system. ESFAC is a dedicated safety
TRAIN B
Fig. 2. Digital security level DCS architecture diagram
versely affected by the auxiliary function
data, and the auxiliary function data shall
not inhibit or delay the execution of its security
function.
Main and auxiliary data partition
According to the above definition of main
and auxiliary data, we divide the signals in
digital security level DCS.
Digital security level DCS receives instruction
signals from the main control room
safety disk and backup disk. The instruction
data includes equipment control instruction
and alarm and indication signal.
The equipment control instruction belongs
to the main function data, and the alarm
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