IEEE1588Time Synchronizing System Applied To Smart Distribution Grid

The Smart Distribution Grid Wide Area Measurement and Control system with Phasor Measurement Unit(PMU) foundation is the key support technology of Smart Distribution Grid, which puts forward higher requirements with time synchronization technology.The present time synchronization researches are mainly focus on substation automation, as the time synchronization technologies now available have been unable to meet the demands of Smart Distribution Grid protection and control. IEEE1588also called accuracy time synchronization protocol PTP of distributed control and measurement system, can multiplex ethernet communication network, with lower resource usage,lower construction cost but wider range of synchronization and micro-second time correcting precision.Through this protocol we can constitute a wide-area multi-layer unified time correcting system which can cover all distribution network automation terminal nodes with high precision and easy extension.This paper mainly studied the construction and realization of Distribution Grid time correcting system based on IEEE1588technology. Ethernet was chosen as the technology foundation of time correcting system after comparing several kinds of current mainstream communication technologies.Through analysis and comparison of several commonly used synchronization time correcting methods,the feasibility and rationality of IEEE1588’s application in Smart Distribution Grid were demonstrated. We also studied the algorithm principle and model structure of IEEE1588,to eliminate protocol stack jitter by means of playing time stamp in the bottom layer and to eliminate path delay by means of Ping-pong algorithm. At the mean time we elaborated the characteristics of clock models such as Ordinary Clock,Boundary Clock and Transparent Clock etc.The operating principles of The Best Master Clock Algrithm, including Data set comparison algorithm and State decision algorithm, were studied, which laid a theoretical foundation for the subsequent application.The topology structure based on switched ethernet typical Distribution network communication system was also analyzed.We studied the confronting problems of the application of IEEE1588technology in industrial Ethernet.By rational node setting,the segmentation methods of clock time correcting area dealing with the backbone layer and access layer are obtained respectively.We chose the best clock source decanting point,presented main equipment setting method of presice clock sorce and studied the multiple redundant methods when time correcting method falied. Eventally,a strong multi-layer wide-area time correcting network was constructed, which is well-organized, well-bedded, highly reliable and convenient for management and construction.We Studied the hardware interface problem of IEEE1588in STM32F4development board;To complete the transplantation of PTPD components in RT-Thread,the network driver of IEEE1588on in RT-Thread was modified. We realized the best master clock algorithm and message processing etc.which are the core functions of IEEE1588.Realize the best master clock algorithm and message processing IEEE1588core function;Finally some verification and testing work for the synchronization clock correcting functions of power distribution terminal device was done,the IEEE1588correcting time system of multiplexing industrial ethernet Distribution communication network can realize the accuracy of1millisecond.To make a certain contribution to the theory and practice for the further development of wide-area measurement and control system of intelligent distribution network,event management of intelligent power distribution network and wide-area protection of intelligent distribution network.