The Research Of Communication Between Computer And Rtu And Reaearch Of Remote Data Transfer

The master thesis is aiming at develop a measurement, management and remote monitoring system of nature gas distributing system based on RS232 and Modbus Plus network. The system, which is aimed at the application on the super and sub stations of nature gas, basically realize the following functions for each nature gas stations, such as data acquisition, measurement, management and communication between center station and sub stations. The system which has been realized has many remarkable features: real time response, high compatibility, high expandability, high precision, strong reliability and security and friendly man-machine interface etc.Based on the requirement analysis, the thesis has firstly designed the physical structure of whole system and field subsystem, it analyzed the mode of field network and design and realization of software. About the design of physical structure we mainly introduced the system structure of serial port communication and remote communication. About the software design, firstly the thesis introduce the module design of serial port communication based on API and theory of Windows multi-thread programming; secondly we talk about the remarkable advantages of SQL SERVER database and detailed design of database module; thirdly the thesis has researched the modes of remote communication, introduce in detail the design of module of RAS and Socket communication; at last because of more and more attention to the security of network and data transfer, we have discussed the Data Encryption Standard, and developed our own data encryption system for the monitoring and control system. In the end of the thesis, we have also put forward the future prospect of industry process control field.