Research On Distribution Automation Terminal With Self-description Ability

With the continuous development of smart distribution network,the traditional distribution automation terminals have been gradually upgraded because they don't have the ability of self-describing and plug-and-play.It is very important to realize the self-description and plug-and-play function of distribution automation terminal,which can improve the automation degree and the quality of power supply.In this paper,the IEC 61850 standard,which is widely used in the intelligent substation,is introduced into the intelligent distribution network,which can make distribution automation terminal with the ability of self-describing and eliminate the manual process in terminal power configuration;At the same time,the improved algorithm based on the distribution automation terminal is proposed to improve the clock synchronization precision.Distribution automation terminal has the functions of telemetry,telesignalling,remote control,feeder protection and equipment condition monitoring,which is the basis for the realization of various functions of intelligent distribution network.In this paper,the function of distribution automation terminal is decomposed and abstracted,and its functions are divided into three categories:SCADA,protection and equipment status monitoring.Object oriented modeling method based on IEC 61850 is used to build information model of terminals.Based on the extension protocol of IEC 60870-5-104,the model file transfer service is mapped to the IEC 60870-5-104 protocol extension message,which solves the problem that the IEC 60870-5-104 protocol is incompatible with the model information.Finally,for the physical propagation of the communication network is asymmetric to the forward and backward delay when the IEEE 1588 protocol is applied,the improved algorithm for clock synchronization compensation of the distribution automation terminal is presented.On the basis of previous research,this paper designs a kind of distribution automation terminal based on ARM and DSP.The functions of terminal registration,automatic configuration,file transfer,data transmission and historical data recording are tested by running the plug-and-play test software on the computer,which validates the feasibility of realization scheme of the terminal self-description function proposed in this paper.At the same time,this paper builds the node model of distribution automation terminal and control center in OPNET simulation software.The end-to-end delay and the time offset of the two cases are compared by the experimental waveform.And the results show the superiority of the algorithm.