Research On Structural Vulnerability Assessment Model Of Microgrid System Based On Complex Network

With the development of large power grid,small-scale distributed generation system plays an increasingly important role in large power grid.The purpose of microgrid is to realize the flexible and efficient use of distributed power,and to solve a large number of forms of distributed power grid connection problems.The application of microgrid will also bring many benefits,such as large-scale access to renewable energy and distributed power,which can make the load get a variety of energy forms,high reliability supply.At the same time,microgrid has vulnerability,its high-speed development will increase the complexity of large power grid operation,and further increase the possibility of grid failure.However,it is of great significance to study the vulnerability assessment model of microgrid system structure for improving the reliability of smart grid.Firstly,this paper summarizes the research results of microgrid vulnerability,complex network theory and vulnerability assessment model of power system structure at home and abroad,and summarizes its research status and development trends.Then it introduces the basic content of complex network theory,including the small world network,scale-free network,random network and other commonly used complex network models.Then it introduces the commonly used vulnerability assessment methods and makes a comparative analysis of these methods.Secondly,the typical vulnerability characteristics of microgrid are analyzed from the aspects of network structure and operation state.Combined with the statistical characteristics of power system in complex network theory,the traditional basic statistical characteristics of complex network theory such as node degree and clustering coefficient in the undirected network model are extracted and constructed Based on the results of vulnerability analysis and vulnerability identification of key risk factors of microgrid,an evaluation index system of microgrid vulnerability is established.Based on the above research,a vulnerability evaluation model of microgrid system structure is established with the energy demand management of microgrid system and the diversified power quality of users as the core,the complex network theory as the theoretical basis,and the analytic hierarchy process.Finally,the vulnerability assessment model of microgrid system structure is empirically analyzed.After the theoretical research on the structure vulnerability of microgrid system.it is applied to the empirical analysis.Taking the prototype of microgrid certs and IEEE-39 node standard system as an example,the vulnerability model of microgrid structure based on the complex network theory in this paper is tested,which verifies the scientificity and validity of the model.Based on the analysis of the risk and vulnerability of microgrid,this paper studies the vulnerability assessment model of microgrid system structure,applies the theories and methods related to complex network to the vulnerability assessment of microgrid,establishes a scientific and systematic vulnerability assessment index system of microgrid,constructs the corresponding assessment model for the structural vulnerability of microgrid,and verifies the feasibility and effectiveness of the model by simulation,It provides theoretical support for the safe and stable operation of microgrid.