Functions and Characteristics of Large DCS Control System
1、 Has an open structure and strong scalability
1. Domain structure
Adopting the concept of ‘domain’. Divide the entire large-scale control system into several relatively independent subsystems using a high-speed real-time redundant network. Each subsystem constitutes a domain and is a fully functional DCS system.
2. Internationally open fieldbus standards
3. Standard Client/Server structure
4. Open network architecture
▲ Redundant 100Mbps Ethernet
▲ Standard RS485, RS232 communication protocol (MODBUS protocol)
▲ Field bus interface and wireless communication protocol of FF protocol
5. Open operating system
Adopting the WINDOWSNT operating system and providing ODBC and OPC interfaces;
6. Standard control configuration tools
The system adopts the IEC1131-3 standard control configuration tool, which can provide users with SFC (sequential flow diagram), FBD (functional block diagram), LD (ladder diagram), ST (structural text) and other methods for control configuration.
2、 The most advanced system performance
Large DCS control systems, with their powerful network architecture and processing hardware, support very powerful software functions and can meet almost all user requirements.
▲ Choose high-performance industrial control computers for servers, with a CPU frequency of no less than 2GHz, memory of no less than 512MB, and hard disk of no less than 80G;
▲ Operator station and engineer station: The CPU adopts a Pentium 4 or higher processor, with a main frequency of no less than 1GHz, memory of no less than 256M, hard disk of no less than 40G, and display resolution of 1600 × 1280;
▲ Control station main control unit: CPU Pentium II or above, with 32M memory and 2M graphics memory;
All I/O signal processing units are intelligent structures.
▲ Rich full Chinese character graphic configuration, capable of achieving complex and beautiful graphical interfaces, and supporting real-time display of animation technology, graphic scaling technology, multi-level window technology, various data, curves, bar charts, various dashboards, etc;
The powerful control configuration can achieve various batch processing processes, PID circuits, complex circuits, logic circuits, hybrid circuits, as well as advanced control algorithms and special formula control;
▲ Rich historical record analysis and processing, log record processing, statistical reports on alarm records, and statistical analysis reports on accident reminders;
3、 High reliability of system hardware and software
▲ Adopting a small module structure on the I/O processing unit to further disperse the danger;
Equipped with a control loop module, it can achieve two PID control, cascade control, compensation control, fast action loop, etc;
Multiple overvoltage and overcurrent protection measures have been added at the interface for each signal, ensuring that each board is not damaged under large signal interference;
Referring to the design standards for nuclear power safety computer systems, a large number of measures have been taken to ensure software reliability.
The operating station adopts the Windows NT operating system, while the control station adopts QNX to ensure the reliability and real-time performance of the control station.