Myeong-Soo Kim’s research while affiliated with Dankook University and other places

This study proposes an electric vehicle (EV) smart panel board and its control method on the basis of charging scheduling. The proposed system consists of batteries, a three-phase battery charger, three single-phase inverters, transfer switches for electric power distribution, and a controller. The three-phase battery charger usually charges the batteries at midnight when electric rates are cheap and in light load. When the electric power consumption of the EV standard chargers connected to one phase of the power line is relatively large or when a blackout occurs, the electric power stored in the battery is supplied by discharging through the inverters to the EV standard chargers. As a result, the value of peak load and the charging electric power quantity supplied from a utility grid are reduced, and the current unbalance is improved. The usefulness of the proposed system is confirmed through simulations, experiments, and case studies.

In this paper, we have analyzed the power consumption property of EVs(Electric Vehicles) chargers established in a public place, proposed reasonable demand factors by the number of established EV chargers and its control method in apartments. The optimization of power system and the suppression of the peak load can be controlled through the proposed demand factors and charging scheduling control algorithm. In this paper, electrical design and an case analysis were carried out on a sample apartment complex to prove the effectiveness of the power system. As a result, emergency power transformer capacity has been reduced by approximately 25%, and we have confirmed that the electric rates saving and the control of peak load value is possible.

This paper proposes a switching type secondary battery discharge system capable of zero-voltage discharge. The proposed system can discharge until the voltage of a battery reaches 0[V] even in the domain with low battery voltage, while maintaining the discharge current uniformly at a set point. In order to confirm usefulness of the proposed system, this paper performed its simulation and verified its results through an experiment.

This paper proposes a boost type inverter system to compensate the voltage sag has appeared in voltage sources. If the voltage sag has appeared in input voltage, a boost converter would be operated to compensate it in the boost type inverter system. The boost converter would not be operated when the magnitude of input voltage is more than 90 %, and the output voltage is kept constant by a direct-quadrature frame controller in the single-phase PWM inverter. A 300 W class boost type inverter system was simulated, and the validity of the proposed system was verified by carrying out experiments.