Research And Application Of New Communication Technologies And Feasibility Algorithms In Process Automation Engineering

With the rapid development of modern science and technology,the control theory and instrumentation technology get the constant improvement.Now,the system integration process of process automation has been beyond the confines of the traditional model,gradually to the network,intelligent direction.In the past,a large number of research results on the process control theory have been investigated by lots of scholars,which significantly improved the control performance of the system.Compared with the control theory research,there are few results for the research on the data acquisition process and control signal transmission optimization process.In fact,the analysis and synthesis of the system in control theory often need many ideal assumptions,such as,data without packet dropout in the network transmission,data transmission not affected by bandwidth,transmission delay far less than the sampling period,etc..However,in the control system,due to the incompatible between a large amount of data acquisition and bus communication protocol,the existence of multiple control loops,the aforementioned assumptions are usually not satisfied,which greatly limits the application of control theory.In this work,OPC UA communication technology and PROFINET-based synchronous communication technology are applied to process automation system integration.On the one hand,amount of data transmission in the process of communication will be raised to solve the incompatible problem of the bus communication protocol.On the other hand,the control signal transmission execution process will be optimized.In the fail safe parking system of heating furnace,fault parking protection movement speed is more than doubled compared with conventional control method,which greatly enhance the safety of the system and improve the reliability of the control system.Meanwhile,considering the existence of uncertain interference in the control system,the sensor data transmitting to the system control decisions has a certain inaccuracy,thus this bring great inconvenience for the control system.In this work,the filtering technology of multi-source information fusion is introduced into the control system in order to strengthen the adaptive ability and fault-tolerant ability of the system,and improve the reliability of the control system.Considering the implementation of forward-looking and practicability in process control engineering,this study includes the following main work content:(1)The advantages of OPC UA framework are firstly analyzed in distributed data detection.Moreover,the OPC UA client data acquisition interface is designed to the incompatible problem of the bus communication protocol based on TCP / IP link.(2)The problem of serious hysteresis because of the control cycle longer add to the difficulties for the real-time synchronization control of the control algorithm.A kind of isochronous synchronous transmission technology is proposed based on PROFINET communication,and its transmission mechanism and algorithm design process are analyzed emphatically.(3)The OPC UA communication technology,isochronous communication technology and filtering fusion technology will be applied to the design of safety interlock system about heating furnace parking processing,and the corresponding design ideas and algorithms of SCL language implementation process are given.(4)For the white noise problem of the common sensors,the PID control algorithm based on Kalman filter is designed by means of the flexibility and ease of use of SCL language.