Assessment Method for the Impact of Electric Vehicles Charging Load on Distribution Network Voltage Quality Considering Time-of-Use Electricity Price

A method based on kernel density estimation theory is suggested to examine the influence of time-of-use power prices on electric car charging demand on distribution network voltage quality. Firstly, a random charging load model for electric vehicles based on the Monte Carlo approach is created, and the electric vehicles charging load model under different user response coefficients η in time-of-use electricity price is also established. Secondly, probability flow calculation formed by Monte Carlo method simulation is used to form kernel samples, and then a kernel density function is constructed. After that, an importance sampling simulation is carried out, and the probability flow solution is used to analyze the node voltage. Four indicators, node voltage limit violation probability, node voltage fluctuation index, node voltage confidence level, and confidence interval, are used to evaluate the distribution network's quality of voltage. The effectiveness and viability of the proposed method are demonstrated by the simulation results.