Design And Implementation Of Upper Computer Software Of Gas-Gate Station's Scada System Based On WinCC

As the independent sub-station of City Gas Company, the Gas-Gate Station must not only supply adequate gas for industries and residents, but also make sure of security, monitor and control gas effectively. These jobs can be done well by the SCADA system of Gas-Gate Station, it is playing an very important role in the station's business.The design and implementation of software on upper computer in the SCADA system of Gas-Gate Station has been described detailedly in this thesis. It analysises relevance of the subject, and designed a complete SCADA system of Gas-Gate Station. This system consists of upper and lower computer component. the lower computer uses S7-200 PLC to collect field data of the gas-gate station; the upper computer uses WinCC as the configuration tool to show user intuitive interface that including layout of the station, production data and alarm information, by configurating a series of typical interface, and designing variables to deal with field data and archive, designing alarm monitor and archive, designing movements of remote controlling electric valves and so on. At the same time, the upper computer is designed to update field data of Gas-Gate Station to control center of city immediately by specialized data reporting software.The communication principles and implementation process between upper and lower computer and the data reporting software have been designed fully. The former uses siemens PC Access software to build the OPC protocol channel between WinCC and S7-200 PLC; the latter uses GPRS model to build the wireless communication channel, the data transmission protocol is Modbus between WinCC and GPRS, and mobile network between GPRS and control center of city. The communication program connects processes of collecting data, dealing with data, and updating data automatically, so that people who work at control center of city can monitor field data and situation of sub-station remotely.The SCADA system of Gas-Gate Station has been applied on actual project successfully and proved with abilities of data collecting and processing and remote controlling of electric valves and alarm immediately and effectively, and has good anti-interference ablity and smooth working ability too.