Mobile QR Code QR CODE : The Korean Institute of Power Electronics
Title Output Voltage Control Technique Using Current Forward Compensation for Phase Shifted Full Bridge Converter Without Output Capacitor
Authors You-Seung Shin ; Seung-Woo Baek ; Hag-Wone Kim ; Kwan-Yual Cho ; Jeong-Won Kang
Page pp.40-47
ISSN 1229-2214
Keywords PSFB (Phase Shift Full Bridge Converter); Ballast water; Voltage control
Abstract Lithium-ion secondary batteries exhibit advantageous characteristics such as high voltage, high energy density, and long life, allowing them to be widely used in both military and daily life. However, the lithium-ion secondary battery does have its limitation; for example, the output power and capacity are readily decreased due to the increased internal impedance during discharging at a lower temperature (-32°C, military requirement). Also, during charging at a lower temperature, lithium dendrite growth is accelerated at the anode, thereby decreasing the battery capacity and life as well. This paper describes a study that involves increasing the internal temperature of lithium-ion secondary battery by energy circulation operation in a low-temperature environment. The energy circulation operation allows the lithium-ion secondary battery to alternately charge and discharge, while the internal resistance of lithium-ion battery acts as a heating element to raise its own temperature. Therefore, the energy circulation operation method and device were newly designed based on the electrochemical impedance spectroscopy of the lithium-ion secondary battery to mediate the battery performance at a lower temperature. Through the energy circulation operation of lithium ion secondary battery, as a result of the heat generated from internal resistance in an extremely low-temperature environment, the temperature of the lithium-ion secondary battery increased by more than 20°C within 10 minutes and showed a 75% discharging capacity compared with that at room temperature.