10-09-2013, 02:39 PM
Prototype of 5.8 GHz Wireless Power Transmission System for Electric Vehicle System
Wireless Power Transmission .pdf (Size: 1.01 MB / Downloads: 57)
Abstract
In this paper, we describe the developed prototype
of 5.8GHz wireless power transmission system with a 4×4
rectenna array for electric vehicles. The rectenna element is a
microstrip patch antenna with PTFT board of 10 dielectric
constant and 1.6 mm thick that has a gain of 6dBi. The
conversion efficiencies are 49% and 75% at the transmission
distance of 200mm and 400mm.
INTRODUCTION
During the last few decades, increased concern over the
environmental impact of the petroleum-based transportation
infrastructure, along with the specter of peak oil, has led to
renewed interest in an electric transportation infrastructure.
Battery-powered electric vehicles (EVs) seem like an ideal
solution to deal with the energy crisis and global warming
since they have zero oil consumption and zero emission [1],
[2].
Electric vehicles differ from fossil fuel-powered vehicles
in that the electricity they consume can be generated from a
wide range of sources, including fossil fuels, nuclear power,
and renewable sources such as tidal power, solar power, and
wind power or any combination of those. However it is
generated, this energy is then transmitted to the vehicle
through use of overhead lines, wireless energy transfer such
as inductive charging, or a direct connection through an
electrical cable [3], [4]. The electricity may then be stored
onboard the vehicle using a battery, flywheel, or super-
capacitors. Vehicles making use of engines working on the
principle of combustion can usually only derive their energy
from a single or a few sources, usually non-renewable fossil
fuels. A key advantage of electric or hybrid electric vehicles
is regenerative braking and suspension, their ability to
recover energy normally lost during braking as electricity to
be restored to the on-board battery [5].
EXPERIMENTAL RESULTS
The system specifications are summarized in Table 1.
Fig.6 shows the experimental configuration of the wireless
power transmission for electric vehicles is provided by a
field effect transistor (FET) oscillator and divided into four
elements using a power divider. Four FET amplifiers with
the output power of 1 watt each are used to have totally 4
watts output power. Each microwave is guided to an antenna
through a coaxial cable. In this experiment, a horn antenna,
whose exit plane size is 112mm×85mm, is used and four
horn antennas are arranged as shown in Fig. 7. Each horn
antenna gain is 16dBi.
CONCLUSION
In this paper, a 4×4 rectenna array has been developed
for electric vehicles. The rectenna element is a microstrip
patch antenna that has a gain of 6dBi. The conversion
efficiencies are 49% and 75% at the transmission distance of
200mm and 400mm, respectively. Without transmission
beamforming, the incident power density is not uniform for a
large array. Therefore, not all of the rectenna elements have
the same output voltage due to their different positions. From
this reason, transmitter beamforming is necessary to increase
the conversion efficiency.