Residential Charging Scheduling of Electric Vehicles in Brazilian Context

This paper presents a methodology to schedule the charging of Electric Vehicles (EVs) in order to maintain the loading of distribution transformer under the nameplate load while reducing charging costs. Brazilian consumption characteristics, mobility pattern and tariff structure are considered to design an optimization algorithm. While the demand of dwellings are estimated from typical load curves of a distribution utility located in the South of Brazil, the demand of EVs are estimated from mobility survey data. Adopting the current Brazilian tariff structure, coefficients of the objective function are formulated in order to schedule the charging of EVs to satisfy the following goals: limit the power demand requested to the distribution transformer, cope the demand of EVs with lower demand of dwellings and reduce the charging costs. The results shows that, in addition to prevent the overloading of distribution transformer, the charging only occurs in periods of higher tariff when necessary, whereas most of it occurs during late night and early morning, corresponding to cost reduction by purchasing energy during lower tariff prices