Plug-in electric vehicle charging demand estimation based on queueing network analysis

Charging stations are critical infrastructure for the integration of plug-in electric vehicles (PEVs) in the future distribution systems. With a steadily increasing PEV penetration level, the PEV charging demands of charging stations are expected to constitute a significant portion of the total electric power demands. An accurate estimation of PEV charging demands is crucial for the planning and operation of future distribution systems. However, the estimation remains a challenging issue, as the charging demands of nearby charging stations are closely correlated to each other and depend on vehicle drivers´ response to charging prices. The evaluation of charging demands is further complicated by the highly dynamic vehicle mobility, which results in random PEV arrivals and departures. In order to address these challenges, a BCMP queueing network model is presented in this paper, in which each charging station is modeled as a service center with multiple servers (chargers) and PEVs are modeled as the customers in the service centers. Based on the stationary distribution of the number of PEVs in each charging station, the statistics of PEV charging demands can be obtained. The analytical model is validated by a case study based on realistic vehicle statistics extracted from 2009 National Household Travel Survey and New York State Transportation Federation Traffic Data Viewer.