| There are problems in the distribution Internet of Things(D-Io T),such as difficult maintenance,weak monitoring and poor interoperability of devices.Based on IEC 61850,the information model and information exchange method of intelligent electronic devices(IEDs)are standardized,which can realize the interconnection,intercommunication,plug and play and data fusion of devices.After analyzing the communication scenarios and requirements between cloud master stations of the D-Io T and edge devices,this paper summarizes the IEC 61850 communication subset used for the communication between cloud master stations of the D-Io T and edge devices,and proposes the application layer protocol using MQTT(Message Queuing Telemetry Transport)as the communication protocol.Finally,the feasibility of the mapping scheme is verified by the functional experiment and performance experiment.The specific research contents of this paper are as follows:(1)Analyze the communication scenarios and requirements between cloud master station and edge devices of D-Io T.Firstly,the communication structure and characteristics of the D-Io T system are summarized,and the shortcomings of the current D-Io T communication are summarized.According to the typical interaction scenarios of each function of D-Io T,the requirements of interaction objects,communication content,performance and other aspects are analyzed.Based on this,the IEC 61850 communication service subset of cloud master station of D-Io T and side equipment communication is summarized.(2)MQTT communication mapping for D-Io T is studied.Based on the requirement of communication subset mapping between cloud master station of D-Io T and edge devices,the data mapping and service mapping based on MQTT protocol required for information interaction are analyzed and clarified.The configuration principle and communication architecture of MQTT server in D-Io T are standardized.Taking typical application scenarios as the analysis object,Combined with the characteristics of MQTT protocol,the implementation mechanism of MQTT mapping is studied in detail.(3)An experimental system was built to test the performance of MQTT mapping.Experiment system of MQTT choose EMQ X server,test program using mosquitto.Cul development libraries and MQTT.fx application software and Jmeter test software,etc.Firstly,the feasibility of the mapping scheme was verified through functional experiments.Then,software such as JMeter was used to test the performance of the system.Concurrency,real-time and reliability tests were adopted to verify that the application layer of cloud master station and side device communication using MQTT protocol can meet the communication needs of cloud master station and edge device in the D-Io T.IEC 61850 is applied to the distribution Internet of Things,which can standardize the information model and information exchange method of the system,enhance the interoperability between devices,and realize the interconnection and plug and play of devices.MQTT protocol is more suitable for the communication environment of D-Io T,and its communication performance can meet the communication needs of D-Io T.The research of IEC 61850 to MQTT protocol mapping method in D-Io T can further promote the construction of distribution Internet of Things. |
