Abstract: Analyzed the electric vehicle's travel activity model, considered the space-time distribution characteristics of electric vehicles, based on the actual data, obtained the distribution model of the key influencing factors of electric vehicle charging. The Monte Carlo and binomial distribution methods were used to obtain the charging power curve of a single electric vehicle on working days and non-working days, and then it is possible to quickly calculate the charging load of a large-scale electric vehicle and analyze its demand response potential. This set of algorithms can calculate the charging power of electric vehicles simply and quickly on the basis of taking into account the space-time distribution of electric vehicles.