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July 24, 2013

Report from Presenter

International Conference on Intelligent System Applications to Power Systems (ISAP2013) cosponsored by IEEE Power & Energy Society was held from July 1, 2013 to July 4 in Meiji University Surugadai campus of Tokyo. ISAP is the international conference which was started in 1994 as a result of integration of International Forum on Applications of Neural Networks to Power Systems (ANNPS) and International Conferences on Expert System Applications to Power System (ESAP). Since the first conference (ISAP1994), ISAP has been held every 2 years, and it became the 17th in total this year including the international conference era of the forerunner. More than 200 participants attended this conference, and the extensive discussion about the electric power system like power system control, the basic theory and application of the smart grid, is discussed. In this conference, I presented about the smart charging to prevent simultaneous charging at the time of the EV is penetrated. The presentation was entitled "Intelligent System of the EV Smart Charging based on PV Curve Analysis".


Fig. 1 Simultaneous charging in the
evening

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Fig. 2 Outline of smart charge algorithm
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EV is supposed to penetrate around 5-10% of all vehicles in the near future. At first, we have to consider the following use case from the viewpoint of the user. The use of the vehicle by the general users is a lot for commuting. This may be applied for EV users. So they use EV in the morning to go to work, and use EV in the evening to go back home. Then, it is assumed that users of EV start charging at the same time of having come back home for tomorrow's use. Under such premise, it is more possible that charging congestion occurs between the evening and the night on weekdays (Fig. 1). The voltage at pole-mounted transformer may be dropped as the charge power increases at the power network. In the form of such a charge, test simulation is performed to inspect the problem called the voltage reduction of the distribution system. Smart charge algorithm is developed to calculate electric energy and charging control time for each EV based on the result of PV curve analysis to distribute the simultaneous charging (Fig. 2). This algorithm is applied to standard test data of Institute of Electrical Engineers of Japan, and, as the result of evaluation, power transmission loss is reduced by 2.5%.

(By ISHIDA Takaharu)

Related Papers

  • T. Ishida: "Feasible Study for the Availability of Electric Vehicles for the Stable Operation in Power System Network". EVTeC'11, SS-5-20117248, May 2011.
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