Design And Implementation Of OPC UA Gateway Protocol Compatibility Test System For PLC

In the intelligent manufacturing system,there is an urgent need of the interconnection between the upper information system and the underlying production equipment,so the OPC UA gateway which is compatible with multiple protocols is used widely.In order to ensure the accuracy of the data transmission of multiple protocols of the OPC UA gateway applied at the production site,the OPC UA gateway protocol compatibility needs to be tested.The test system provides protection for the site data collection,device connection,and real-time monitoring for protocol compatible gateways.At the production site,the PLC is the core control device,and it is also an important carrier for on-site production data transmission.After analyzing the protocol compatibility method and function structure of OPC UA gateway oriented to PLC,this paper designs and implements the compatibility test system of OPC UA gateway protocol for PLC based on the requirements of protocol compatibility testing system.The main work includes the following aspects:1.Based on the analysis of the requirements of PLC-based OPC UA gateway protocol compatibility test,this paper designs the overall architecture of the OPC UA gateway protocol compliance testing system for PLC,the functional structure of the testing system software,and the multi-thread testing structure and testing system.2.This paper designs and implements the test case set and test signal configuration point table of the OPC UA gateway protocol compatibility test for PLC in detail.The mapping relationships between the four protocol test signal point addresses are analyzed,and the test signal configuration point tables are designed for the four PLCs and communication protocols,and the protocol compatibility test flow is designed.Finally,combined with XML technology,an automatic test method based on XML script driver is designed to improve the scalability of the system.3.This paper designs the realization of the test system function modules,including the man-machine interaction module,the OPC UA and Modbus/TCP communication client module,the test service module and so on.Combined with the thread pool technology,the method of multi-test task scheduling is designed to improve the test efficiency.Finally,using ASP.NET technology and MySQL database system,a compatibility testing system based on C/S and B/S architectures is developed and implemented.4.The availability of the OPC UA gateway protocol compatibility test system is verified for PLC.First,the test software system is integrated with the hardware load tool,and then the relevant functions in the test software system are verified using the enterprise's protocol compatible gateway product.Finally,the multi-protocol-compliant test of the gateway is completed.