Building Monitoring System In The Opc Client And Server Applications

Building Automation System(BAS) is an important component of Intelligent Building(IB). It's system structure and operation directly affect the operating system of IB.Since more and more advanced automatic devices made by different manufacturers are used in BAS,differences may exist in application program interface,communication protocol of the devices.They seriously affect the opening and inteoperability among subsystems and bring difficulties to the integration of BAS.As one of the latest software data exchange interface standard,the OPC (OLE for Process Control)technology based on COM/DCOM is gradually used in the integration of BAS .The client could access to the field devices with uniform way,get the real-time data and finish the data configuration no matter what kind of the field devices are used.OPC technology brings a more practical and effective method to realize the seamless integration from control layer to management layer of BAS.The thesis introduced the purpose,method and analyzed the problems of integration of BAS,elaborated the design of the monitoring platform and software architechture based on OPC and analyzed the OPC DA specification and the communication machanism between OPC client and server,introduced the design and development method of OPC client with visual C++,resolved some technical problems such as the multithreading programme,OPC interface realization during the development process, achieved to connect multiple OPC servers for data collection and realized the function of management and maintainance.Meanwhile,the thesis introduced some key techniques in the development of OPC Server,including the realization of interfaces and communication module. Finally, the thesis elaborated the test of the OPC Client in the project.Via the test the designed OPC client can connect all the OPC servers in the building successfully,read and write data from OPC server stably and effectively.It realized the function of OPC data access and finally achived to the goal of real-time monitoring and data acquisition of field devices'running condition.