2016 年 5 巻 6 号 p. 429-438
We previously reported a 60Hz wireless power transmission (WPT) system, which is a system that uses the common utility frequency. In the study reported in paper, we solved several issues in order to install this system in a small electric vehicle. First, an accelerated finite difference time domain (FDTD) method using a graphics processing unit was developed to solve the issue of computation time. Next, theoretical equations for the transmission efficiency (η) and power (Pout) that include the stray load loss were derived from an equivalent circuit analysis. A new device was designed based on these theoretical equations, where by η =70% and Pout =451W were achieved for a transmission distance of 150mm. Finally, we attempted to wirelessly charge of a lead storage battery. The overall efficiency of the wireless charging system was maintained at 60% during battery charging.