Research On Harmonic Of Electric Vehicle Chargers

Energy and environment has currently become the most concerned global issues. Energy is the foundation of the economy, and environment is an important factor which constrains economic and social development. Under the circumstances, energy-saving and eco-friendly EV (Electric Vehicles) is in the ascendant.In this paper, the entire research work which focuses on the harmonic generated by EV charging station is closely around the "863 Program". Electric vehicle (EV) chargers are non-linear load in power systems. They present a potential problem to power system in the forms of harmonic currents and poor power factor. Thus it is important to analyze the effect of EV chargers on power system harmonic current before building a charging station. The development of electric vehicles can not be separated from charging station building, so there is a practical significance in the harmonic analysis of EV chargers.The function and general layout of EV charging station are expatiated. In this paper, distribution system of station is designed and theoretical analysis on power quality of charging station is done.A new method of charger modeling is first proposed in the paper. Then, by using Matlab/Simulink as a simulation tool, models for high frequency chargers and for a charging station have been set up on the basis of electric buses parameters, which are useful to the analysis and prediction of harmonic pollution. Factors affecting harmonic current are researched, which provides the choice of charger power and the constructing of charging station with a theoretical basis and technological support.An innovative and practicable algorithm of harmonic for EV charging station is put forward for the first time in this paper. Research shows that when the charging station connected to the power system, it can't meet the harmonic standard and that the simulation methods and the models for high frequency chargers and for a charging station can also be applied to other types of charging stations.In the end, an available programme of harmonic suppression is proposed for EV charging station for the Beijing 2008 Olympics.