Risk Assessment Method of Node Voltage Sag Based on GRA-TOPSIS Model

Accurate evaluation of node voltage sag risk is the premise and foundation for the following effective treatment of voltage sag. In view of the current research status of the voltage sag evaluation system, which is not complete enough and lacks risk evaluation concept, a comprehensive evaluation method of voltage sag risk taking both the power grid side and the user side into account is proposed. Based on the definition of risk evaluation, this method constructs a voltage sag risk evaluation model after analyzing the perspectives of probabilistic prediction and selection of severity indices. Then, the assessment matrix is formed by combination weighting and using game theory and the general process of voltage sag risk evaluation based on GRA-TOPSIS model is given. Finally, an example analysis which takes the data of voltage sag events of multiple sensitive users in a certain province as samples is carried out to verify the rationality, accuracy and good practicality of the evaluation strategy.