The Monitoring System Based On PSTN For Heating Power Stations

With the central heating system's scale expanding in the city, the conventional manual management and operation can't meet the needs of heating power stations gradually. So it's necessary to apply the computer control system to improve the heating quality and efficiency. Now we have researched and developed a distributed computer monitoring system based on PSTN for heating power stations in this graduate program.First, this thesis proposes its general design, which divides the system into three parts: a control center, RTUs (remote terminal unit) and the communication. The control center monitors all stations and maintains operation data integrity for management. The RTU monitors realtime parameters of a station and diagnoses its abnormal status. The communication transports data between the control center and RTUs. In the general frame, the thesis discusses the R&D process of RTUs and the communication in detail.The RTU has abandon the traditional architecture exploitured by singlechip, It use system architecture made up of embedded PC that was extensible and open . The RTU using Linux as his operating system, So the real time and stabilization are strengthened. The RTU gather the inputs such as MBus data, 4~20mA analog signals and pulse count, and also supply the graphic user interface. Using GUI the RTU can display and save these data, Finally transmit these data to the control center.The monitoring system has built bidirectional PPP dialing server and client. The control center and RTUs are able to dial-up each other and establish TCP/IP connection based on PSTN with PPP protocol. Then we utilize socket network API to...