Application And Development Of EtherCAT In Substation Monitoring System

Substation monitoring system has been rapidly popularized,the equipment is convenient to operate and the information could be transmitted rapidly,which is the basis for the safe operation of the power system,so as to meet people’s demand for power supply reliability and security.At present,the vast majority of newly built substations adopt integrated automation technology,which requires a strong inter-station communication capability.In other words,communication is the key of substation automation system,and the rapidity,certainty and reliability of communication network information transmission determine the availability of substation automation system.As the configuration mode of substation automation system changes from centralized mode,centralized with distributed mode to completely distributed mode,fieldbus technology is introduced into the network communication of substation system with its characteristics of simplicity and ease of use,convenient networking and strong anti-interference ability.In order to further optimize,also for the development of substation demand,the choice of a more efficient fieldbus technology is urgent.EtherCAT fieldbus protocol is an open real-time Ethernet protocol proposed by Beckhoff.Its advantages are high performance,low cost and flexible topology.Due to the application of distributed clock mechanism,the synchronization error between slave station devices can be controlled at ns level,which meets the requirement of high synchronization of control system.Since EtherCAT industrial Ethernet has the advantages of good real-time performance,reliability and low maintenance cost,the application of EtherCAT in substation monitoring system is the purpose of this research.This paper focuses on the communication between EtherCAT master and slave stations,clarifies the EtherCAT communication principle and master station protocol stack,and then introduces various design schemes of master and slave stations.Finally,LAN9252 is selected as ESC and STM32F407 as the microprocessor of slave station.The slave module is designed to complete the communication digital data and analog data in the substation communication system.At the same time,it also introduces the configuration of XML file and the rewriting of STM32 programs.The IgH EtherCAT Master with good portability,mature development and free open source was selected for the research and development design of the Master station.EtherCAT Master has the advantages of good portability,mature development and free,so it is selected for the development and design of EtherCAT master.In addition,the Linux was extended in real time through Xenomai to show EtherCAT’s real time performance.The test of EtherCAT communication shows that the functions of slave and master are achieved successfully.Message transmission time and jitter are in μs level.So,the research purpose of this paper has been completed,with a good practical value.Subsequently,the software of the substation monitoring system is designed based on the successful communication between the EtherCAT master and slave stations.Finally,on the basis of the subject research,this paper puts the contents need to be further studied and improved in the future.