Design Of Communication Gateway Based On PROFINET Protocol

With the extensive application of Ethernet and information technology(IT),integrating Ethernet technology and IT technology into automation systems is an inevitable demand for automation technology upgrades,so PROFINET technology came into being.PROFINET technology is an open and innovative industrial Ethernet standard,which can meet the various requirements of automation technology.PROFINET supports both standard TCP / IP communication and time-deterministic functions that cannot be achieved with standard Ethernet.This makes it an ideal industrial network.At present,the sensors,frequency converters,and various instruments widely used in industrial fields mostly use Modbus protocol to communicate with external controllers in series.Enterprises cannot network management of various equipment,which hinders enterprise digitalization and networkization.development of.Aiming at the problem that the Modbus network cannot directly communicate with the PROFINET network,a ROFINET-Modbus communication gateway system based on Siemens ERTEC200 P is designed to realize the data communication between the PROFINET network and the Modbus network.This gateway can be configured as a master station or a slave station on the Modbus side.It is flexible and easy to use,and the single data transmission can reach up to 1440 bytes.At the same time,the real-time performance of the PROFINET data frame is studied.According to the PROFINET data frame,The structure and the forwarding method in the switch deduced the delay of data transmission in the network,and gave three performance optimization methods,which played a theoretical guiding role in practical applications.This article first introduces the PROFINET industrial Ethernet technology,elaborates the related concepts of PROFINET IO and analyzes the communication principle of PROFINET,and finally draws the characteristics of PROFINET communication.According to the characteristics of RPOFINET communication,the theoretical derivation of PROFINET real-time performance is given,and three methods to optimize the performance of PROFINET are given: fast forwarding,data frame packing and data segmentation,which provides theoretical guidance for practical applications.According to the standard reference model of PROFINET protocol and Modbus protocol,the overall design scheme of the gateway system is proposed,and the corresponding hardware platform is designed and manufactured according to the overall scheme.The software for the gateway system protocol conversion is written,and the software and hardware of the gateway system are completed.Joint debugging.Finally,a system test platform was built,and the gateway function and performance tests were completed.The test results show that the gateway system can normally complete the function of converting the PROFINET protocol and the Modbus protocol.