Design And Realization Of Communication Network For Distributed Realtime Measurement And Control System

With the development of the nuclear energy power-making technology,the request for real-time measurement and control system of nuclear dynamical equipment is higher. The real-time measurement and control system of nuclear dynamical equipment is important in the nuclear power plant, and is responsible for the measurement and control function of nuclear dynamical equipment. It is one of the important parts which decide whether the nuclear power plant could run with safety, stabilization and economy. So it is important and necessary to build a real-time measurement and control system software. The apply of computer to measurement and control system of dynamical equipment is an important development trend of automatization and intelligenece of nuclear dynamical equipment.With the development of computer, communication, network, control, large scale integration circuit technology, the measurement and control system in the nuclear power plant changes greatly. It develops in the direction of network, automatization and intelligenece. In this paper, we will develop and research real-time measurement and control system based on heterogeneous network and real-time data sampling system based on industry control computer. The real-time measurement and control system based on heterogeneous network has many merits ,for example, strong computer function, high stabilization, good realtime and so on. This paper develops the nuclear dynamical equipment heterogeneous network communication software,which is based on QNX and Windows OS and make many kinds of information in measurement and control system transfer in the computers,and makes them become an organic whole. During the development, we apply the socket based on TCP/IP ,and introduce client/server(C/S) model to write software, and intuduce simultaneous server. Data sampling is the precondition of realization of field control system. The real-time data sampling system based on industry control computer introduces themulti-thread technology, and makes full use of multi-mask characteristic of QNX. It increases the speed and reliability of data sampling for real-time measurement and control system greatly, and removes the coupling of the sensors effectively to increase the realtime, reliability and stability of system. In the real-time measurement and control system and communication system, the cable is used to connect the computers and the sensors. RS232/485 serial interface is often used for communication channel. So how to make the serial interface transmit data reliably is one of the most key problems. In this paper, the interrupt technology is used to arise the speed and veracity of serial communication. The modules which complete different functions in the measurement and control system need to carry through the transmission and exchange of data, information, instruction and so on. In this paper, in order to satisfy the needs, we develop data transmission and handling software module based on the common shared memory and message passing. Through the test of simple measurement and control system, the result shows the right and feasibility of software.