for distribution grid containing electric vehicle

 

 

LUO Qing, HUANG Min xiang

 

(College of Electrical Engineering Zhejiang University, Hangzhou 310027, China)

 

 

Abstract: Aiming at the electric vehicle charging load has the characteristics of randomness and intermittent, the data of electric vehicle charging behavior was analyzed; the charging power demand model of electric vehicle was established. The expectation and standard variance of the charging power demand were calculated through Monte Carlo simulation method. For the IEEE33 node distribution system that considers random access of the electric vehicle charging load, the probabilistic power flow were calculated with the software Matlab, mathematic statistical characteristics such as expectation, variance and probability density function of each node′s voltage, current and branch power were works out with the forward and backward substitution method. the concept of accommodate capacity of electric vehicles was introduced and the IEEE33 node distribution system′s accommodated capacity of connecting electric vehicles was analyzed from the viewpoint of voltage limit violation. The results indicate that in order to ensure the stability and safety of power system, the number of electric vehicles should be controlled.

 

Key words: electric vehicle; charging load model; probabilistic power flow; accommodated capacity