Study And Analysis On Power Grid Operation State Characteristics Based On Entropy Weight Method

The security and stability of power system are the focus of attention and monitoring of the operation personnel.The complexity of these issues is prominent,which can be expressed as thermal security,voltage stability,power-angle stability etc.While the load level of power grid is closely related to the security and stability issues which may be caused by heavy load of power grid.Consequently,this paper process from various aspects of load level of power grid and introduces an objective weighting method—entropy weight method.In order to analyze the characteristics and trends of grid operation status,this paper presents an analysis and evaluation approach of grid operating state characteristics based on entropy weight method.The main contents are as follows:1.In term of the different performance of system security and stability,three evaluation indexes of transmission lines load index,including branch load rate,branch voltage loss and phase angle difference between nodes at both ends of the branch,are selected as the measure of various aspects of power grid load level and then the relation between the unevenness of power flow distribution and power grid load level is analyzed.2.The concept of entropy is introduced and the entropy of the load index is used to describe the unevenness of the power flow distribution.On this basis,this paper proposes power grid operation state characteristics analysis and evaluation approach of grid operation state characteristics based on entropy weight method.This approach enables operators to evaluate system load levels reasonably and give the characteristics and trends of power system operation state.3.The IEEE 118 bus test system and China southern power grid are analyzed and calculated to verify the conclusion and the validity of the proposed method.