Abstract:
The rapid growth in the penetration rate of electric vehicles accompanies by the irrational proportional planning of charging stations and battery swapping stations, resulting in a decline of power quality and operational economy of distribution network. The establishment of a power quality index system is therefore imperative for evaluating the proportional planning. Traditional weighting methods for the index system fail to accurately describe the relationship between the indexes. As a result, an evaluation method for power quality of distribution network is proposed based on the G1 and the CRITIC methods. Firstly, the power quality index system of distribution network is established by quantifying indexes based on voltage overlimit rate and stability margin, feeder balance and loss, as well as current harmonic distortion rate. Secondly, the Kendall correlation coefficient is utilized to improve the CRITIC objective weighting method. Each index in the system is weighted by the subjective and objective combination weighting method. The proportional planning evaluation of Charging Stations and Battery Swapping Stations in different functional areas is then conducted using the weighted index system. Finally, the rationality of the proposed power quality index system and the effectiveness of the improved weighting method are verified through analysis of simulation examples.