Furtive 충전을 적용한 Yard tractor용 무선충전장치

Abstract

Abstract Compared to the internal combustion engine, electric vehicle is eco-friendly and does not emit environmental pollutants such as COx, NOx and SOx. Although so a number of studies have been performed for practical uses, the electric vehicle has not been widely used because of problems of high cost and long charging time as compared to the internal combustion engine vehicle. Since yard tractor is one of the major sources of pollutants in container yard, it has to be improved in order to actively cope with the strengthened international regulations. Therefore, eco-friendly electric yard tractor is developed, but it has the disadvantage of high cost and long charging time. Considering the waiting period for the quay-wall crane or RTGC(Rubber Tyred Gantry crane) to load or unload containers, charging of battery can be done stealthily without affecting regular operation schedule of yard tractors. This kind of battery charging performed stealthily is called furtive charging. For this furtive charging, wireless charging is essential. Two problems, high cost and long charging time, can be alleviated. In this thesis, wireless charging is investigated to achieve furtive charging for yard tractor. A new resonant inverter with fully compensated isolation transformer is proposed. This inverter shows good performance when its load requires constant current. A prototype of charging system has been built and experimented. The validity of the proposed resonant inverter has been demonstrated.