Urban air pollution concerns has led to an increase in electricvehicles popularity. Plug-in Electric Vehicles (PEVs) require charging stationsinfrastructure throughout the traort networks. Traffic in an urban traortnetwork could be affected by the locations of the charging stations. On theother hand, charging stations are new and relatively large electrical energydemands for distribution networks whose locations are very important from distributionnetworks planning and operating points of views. However, charging stations aregenerally connected to the distribution networks using power electronicdevices. Thus, these stations could be used as active filters for conditioningof harmonic pollutions, as well as reactive power compensators. In this thesis,optimal placement of charging stations is defined as an optimization problem.The objective function of this problem includes the total investment cost ofcharging stations construction, the opportunity cost for waiting in the stationqueue and the cost of purchasing active and reactive energy from the upstreamnetwork. The optimization constraints include the operation constraints of thedistribution network in presence of harmonics, the voltage magnitude limits andtotal harmonic distortion (THD) within the allowed range, and also theconstraints related to the urban traort network. In this model, the abilityof charging stations to be used as the active and reactive power compensator filtersis considered. In addition, the impact of locations of charging stations onurban traffic has been considered and modeled. The optimization problem is initially modeled as a mixed integernonlinear programming problem (MILP) and then, using advanced linearizationtechniques, it turns into a mixed integer linear programming problem (MILP).The proposed models are implemented in the GAMS optimization software on twotest systems, and numerical results are provided for the case studies and various scenarios. Numericalresults confirm the ability and efficiency of the proposed model in chargingstations allocation compared to existing models. Keywords Optimal placement of charging stations,Plug-in electric vehicle, harmonic and reactive power compensation, urbantraortation network,electrical distribution network