A new configuration of magnetic coupled power transfer using parallel line feeder

Abstract

This paper newly proposes a configuration of magnetic coupling in wireless power transform using parallel line power feeder. Previous researches mentioned that coil design and optimization of circuit parameters are necessary for strong magnetic coupled resonance. Then, these constraints prevent expansion of coverage area of wireless power transfer to electric portable devices, and electric vehicles. In order to make breakthrough against these limitations, this paper introduces parallel line as a feeder. The frequency of the electromagnetic wave is selected at 13.56 [MHz] in high frequency (HF) band, which is suitable for strong magnetic coupled resonance. Fundamental characteristics are evaluated by using equivalent circuits which are referred to the previous works. Theoretical analysis asserts that impedance transform is necessary in a power source and load circuits. Computer simulation evaluates a mutual inductance between primary and secondary coils, and optimum value of load resistance is clarified. Finally, input impedance and Sparameter are evaluated when power source circuit and feeder circuit are magnetic coupled resonance, these results imply that enhancement of power transfer efficiency is a further study.

Wireless power transfer for electric vehicle at the kilohertz band

“…In a typical wireless power supply system, the use of coil‐shaped units as a power transmitting side is common. However, this method is characterized by the use of a parallel pair of conductive lines as the feeder lines to the power transmission side . Further, if the same frequency is used for power transmission, the power reception device side can use the same equipment as the stationary wireless power supply system.…”

Fast receiver-side load control based on electromagnetic distribution for wireless power transfer using parallel line feeder

“…Although this method achieves the high transfer efficiency, it requires huge cost and complex hardware. We have proposed a WPT using parallel line feeder for easy expansion of charging area [3]. This method is able to expand the charging area just by simply extending the feeder line.…”

Dynamic charging using parallel line feeder with hybrid inductive-capacitive coupling and receiver-side load control

“…In [6], for further reduction of system size and cost, an HF generator is used to power an inductively-coupled parallel line feeder. Because HF displacement currents pass through asphalt and tires, capacitive-coupling is exploited in [7] to realize zero-gap power transfer from the feeder to steel belts of vehicle wheels.…”

“…However, because the wavelength of HF signal (10-100 m) is shorter than the feeder length (several tens meters to kilometers), current and voltage along the feeder follow standing wave pattern which is an alternative of nodes and anti-nodes [8]. As a consequence, both systems in [6] and [7] suffer from nulls in power profile, forcing the receiver to consume battery.…”