Research On Multi Information Protection Strategy Based On Intelligent Substation

With the development of smart grid,the scale of the power grid is gradually expanding,the traditional relay protection unable to meet its speed and reliability because of complex operation mode.Development of intelligent substation technology,the standard of IEC61850 and Intelligent electronic equipment make the possibility of multiple information sharing provided for the station domain.It provides a good platform for studying the new backup protection of multi information fusion.This paper focuses on the principle and algorithm of multi information fusion relay protection,which is embodied in the following aspects:Firstly,the concept of station protection in Smart Substation is briefly summarized.The basic function of station domain protection is expounded.And according to the IEC61850 communication protocol,the structure model of station area protection is built.The functions of each component in the station domain protection are introduced in detail.According to the development trend of substation protection in smart substations,The function and operation mode of intelligent equipment in smart substation are analyzed.A framework of multi information station domain protection system is proposed.Based on the multi-source information and information sharing and the integration of redundant information,a new type of station protection system based on centralized decision is realized.Secondly,the PSCAD simulation model of the substation is built on the basis of 220 kV substation,and the front-end human-computer interaction interface of the multi-information experimental platform of intelligent substation is designed by using MFC software,and the data interaction between the front-end user interface and the back-end simulation model is realized through the interface program.Then,a multi information fusion algorithm based on evidence theory is proposed.The different fault characteristics of fault lines in substations are analyzed.The fault measure function is constructed by the first half wave,power component and transient fault feature,the evidence fusion recognition framework is established,and the basic distribution reliability is constructed.The comprehensive reliability is obtained through the fusion of evidence theory to determine the fault.Finally,a multi-information substation backup protection scheme is proposed.Substation redundancy information and direction information are used to realize substation backup protection function.