Research On Identification Method Of Key Transmission Lines Of Power Grid Orienting To Situation Awareness

It's of great significance to analyze and identify the key transmission line of power grid in order to maintain the stability and safety of power system as well as prevent large-scale power failure.With the development of interconnected network,wind integration,demand response and other new techniques,the internal structure and operation state of power system are becoming more and more complicated.In order to pick out these key transmission lines from the diversified and complicated system,it's necessary to have a clear understanding of the grid environment,which involves the acquisition,perception and analysis of the ‘grid situation'.In view of this,this paper mainly focuses on the comprehensive analysis and assessment of key transmission lines and applies the concept of situation awareness to the research on key transmission lines.The main work of this paper is as follows:(1)The evaluation index of key transmission lines is improved,and a method based on the super-efficiency data envelopment analysis(DEA)is proposed for comprehensive index calculation.Based on the existing research,this method firstly calculates the single index of transmission lines.Each single index describes the importance of transmission lines from a certain dimension.Secondly,the super-efficiency DEA model is used to synthesize each single index so as to take into account both structural and state vulnerability of each line and to evaluate the key transmission lines from a more comprehensive perspective.The method can ensure the objectivity and relative stability of the analysis results.(2)A method orienting to situation awareness is proposed to analyze key transmission lines.This method is mainly divided into the stage of awareness,understanding and prediction and presentation.Among them,the awareness stage mainly completes the acquisition of basic data and information.In the understanding stage,a dynamic economic dispatch model of power system with the consideration of wind and interruptible load is established so as to solve the network state and calculate the single index of each transmission line.In the prediction and presentation stage,super-efficiency DEA model is used to analyze the key transmission line in single period,and grey relational degree is applied to analyze the key transmission line in full periods.Finally,taking IEEE 24 node system as an example,the validity and effectiveness of the proposed method are verified.The research work in this paper can provide beneficial reference and suggestion for system operators.