Electric vehicles use
electricity as the source for all
or part of their power requirement. Interest in electric vehicle has increased
in the recent times due to the increasing awareness of
the environmental impact of greenhouse
Gas emissions, together with the development of modern lithium-ion
batteries. Electric vehicles (EVs) and plug-in hybrid EVs have a smaller CO2
footprint compared to traditional vehicles that rely exclusively on internal
But it has certain drawbacks which limit their use. Some of them
Recharge Points: Electric
fuelling stations are still in the development stages. Not a lot of places will have electric
fuelling stations for the vehicle.
Electricity isn’t Free:
Sometimes electric cars require a huge charge in order to function properly ,which
may reflect poorly on the electricity bill.
Driving Range and Speed: Electric cars are limited by
range and speed. Most of these cars have range about 50-100 miles and need to
be recharged again.
Recharge Time: While it takes couple of minutes to fuel a gasoline powered
car, an electric car take about 4-6 hours to get fully charged. Therefore, there
is a need of dedicated power stations as the time taken to recharge them is
Replacement: Depending on the type and usage of battery, batteries of
almost all electric cars are required to be changed every 3-10 years.
Thus, many consumers refrain from buying an EV because of anxiety
and concerns regarding charger availability. This is aggravated by the fact
that many people do not own garage and rely on street parking, shopping malls,
and their workplaces for charging.
The development of electrical energy storage systems with
ever-higher energy and power densities has already begun to address the limited
range and long battery-charging time of today’s EVs. There has been
a steady performance improvement of the EVs due to:
higher converter switching frequencies using novel wide-bandgap
soft-switching converter topologies,
and improved modelling and optimization strategies that allow for
the fullest utilization of all system components.
Further,for promoting the use of EVs, it is required that we think
differently about fueling than we do about petroleum fueling, in terms of both
the frequency of fueling events and the venue for these events.There needs to
be more number of distributed automatic chargers that conduct fueling without
human interaction. For this purpose the concept of contactless battery charging
can be explored.
Contactless battery charging of
Inductive charging (also known as wireless charging or cordless charging) uses an electromagnetic field to transfer energy between two
objects through electromagnetic
induction. This is usually done with a charging station. Energy is sent
through an inductive coupling to an electrical device, which can then use that energy
to charge batteries or run the device.
Unique advantages that result from the contactless transmission
via IPT of battery-charging energy across the air gap between a charging
platform embedded in the road surface and a receiver coil on the EV are:
The elimination of the
galvanic connection between the charging station and the vehicle simplifies the
charging process and removes safety concerns related to the handling of the
In addition, automatic power transfer without the need for moving
mechanical components is particularly attractive for charging public
transportation EVs because it enables the charging process to be integrated
with regular vehicle operation via “opportunity charging” at bus stations, taxicab
stands, or traffic lights along the route.
Reduced dwell times for recharging at a depot means that operators
can trim the number of vehicles in their fleets and related operating costs.
More frequent recharging reduces the battery’s depth of discharge,
which extends battery lifetime and
allows dimensioning EVs with a smaller on-board energy storage capacity, thus
lowering initial costs.
The lack of a galvanic connection frees the charging station from
moving mechanical components, which reduces the required maintenance.