ELECTRIC VEHICLE CHARGING SYSTEM AND CHARGING AND BILLING
METHOD
{Technical Field}
{0001}
The present invention relates to an electric vehicle
charging system and a charging and billing method.
{Background Art}
{0002}
Various methods have been proposed for charging secondary
batteries (batteries) of electric vehicles.
{0003}
A power supplying system disclosed in PTL 1 includes a
power transmitting vehicle and a power receiving vehicle
receiving power from the power transmitting vehicle, and an
ECU of the power transmitting vehicle wirelessly transmits
power to the power receiving vehicle, an ECU of the power
receiving vehicle receives the power transmitted from the
power transmitting vehicle and then supplies a driving motor
with the received power to drive the driving motor.
Furthermore, PTL 1 discloses a method for adjusting fees
based on exchanged power wherein the ECU of the power
transmitting vehicle calculates a fee corresponding to a
quantity of the transmitted power to transmit the fee to an
2
information managing center, and the fee is transferred from
an account of an ETC card owner of the power receiving vehicle
to an account of an ETC card owner of the power transmitting
vehicle.
{Citation List}
{Patent Literature}
{0004}
{PTL 1}
Japanese Unexamined Patent Application, Publication No.
2005-168085
{Summary of Invention}
{Technical Problem}
{0005}
The method for adjusting fees based on exchanged power
disclosed in PTL 1, however, relates to power exchange between
moving electric vehicles, and thus, does not relate to power
exchange between a non-moving charging device and an electric
vehicle.
{0006}
The present invention has been made in view of the above
circumstance, and therefore an object thereof is to provide an
electric vehicle charging system and a charging and billing
method in which simple fee adjustment is possible in
accordance with power transmission from a non-moving charging
device to an electric vehicle.
3
{Solution to Problem}
{0007}
In order to solve the aforementioned problem, the
electric vehicle charging system and the charging and billing
method of the present invention employ the following
solutions.
{0008}
Specifically, an electric vehicle charging system
according to a first aspect of the present invention includes
a charging device having a receiving means receiving specific
information transmitted from an electric vehicle, the specific
information being for specifying an owner of the electric
vehicle, and a power transmitting means receiving a power
supply from a commercial power system and transmitting power
for charging a secondary battery to the electric vehicle
transmitting the specific information, the charging device
being arranged at a prescribed position, and a billing device
charging a fee to the owner of the electric vehicle specified
with the specific information in accordance with a quantity of
the power transmitted to the electric vehicle by the charging
device.
{0009}
According to the present configuration, the charging
device arranged at the prescribed position receives the
specific information for specifying the owner of the electric
4
vehicle which is transmitted from the electric vehicle by
using the receiving means, and transmits power for charging
the secondary battery to the electric vehicle which has
transmitted the specific information by using the power
transmitting means which receives a power supply from the
commercial power system. Consequently, the charging to the
secondary battery of the electric vehicle is performed without
reception of the fee on the spot. Note that the prescribed
position is, for example, a road on which the electric vehicle
travels or a parking lot where the electric vehicle parks.
Then, the billing device charges a fee to the owner of
the electric vehicle specified with the specific information
in accordance with a quantity of the power transmitted to the
electric vehicle by the charging device.
Consequently, in the present configuration, simple fee
adjustment is possible in accordance with power transmission
from a non-moving charging device to an electric vehicle.
{0010}
In the aforementioned first aspect, when surplus power is
generated in the power system from which the charging device
receives a power supply, the charging device preferably
transmits power to the electric vehicle.
{0011}
Power generated by natural energy such as solar or wind
power may excessively increase due to instability of natural
5
energy. In this case, when surplus power that excessively
increases is not consumed, a power generation quantity has
been suppressed and consumed wastefully.
Thus, according to the present configuration, when
surplus power is generated in the power system, power is
charged to the secondary battery of the electric vehicle, and
the surplus power generated in the power system can be thereby
utilized without any waste.
{0012}
In the aforementioned first aspect, when surplus power is
generated in the power system from which the charging device
receives a power supply, the charging device preferably
increases power to be transmitted to the electric vehicle.
{0013}
According to the present configuration, when surplus
power is generated in the power system, more power is charged
to the secondary battery of the electric vehicle, and the
surplus power generated in the power system can be thereby
utilized without any waste.
{0014}
In the aforementioned first aspect, it is preferable that
the electric vehicle transmits to the charging device residual
quantity information indicating a quantity of residual charged
power of the secondary battery along with the specific
information, and the charging device, based on the quantity of
6
residual charged power indicated by the residual quantity
information, changes a power transmitting timing or power to
be transmitted to charge the secondary battery so that the
quantity of residual charged power of the secondary battery of
the electric vehicle does not reach or exceed a quantity of
charging power considered not to cause running out of power
during a time period from a start time of the charging to the
secondary battery to a prescribed time.
{0015}
According to the present configuration, the secondary
battery of the electric vehicle is not fully charged, but is
charged with an empty capacity allowing further charging left.
Note that the prescribed time is, for example, a time when an
electricity rate which is lower than that of the other time
periods is started to be applied, that is, when midnight
electric power can be used.
Consequently, in the present configuration, at a timing
suitable for charging the secondary battery of the electric
vehicle, the empty capacity of the secondary battery can be
surely left.
{0016}
In the aforementioned first aspect, it is preferable that
the electric vehicle transmits to the charging device residual
quantity information indicating a quantity of residual charged
power of the secondary battery along with the specific
7
information, and the charging device is arranged along a road
on which the electric vehicle travels, and changes a
proportion of time periods used for wireless power
transmission for a plurality of the electric vehicles
travelling on the road based on the residual quantity
information.
{0017}
According to the present configuration, the charging
device arranged along the road on which the electric vehicle
travels changes the proportion of time periods used for
wireless power transmission for a plurality of the electric
vehicles travelling on the road based on the residual quantity
information. Power is therefore transmitted with priority to
an electric vehicle with a small quantity of residual charged
power, for example. Consequently, in the present
configuration, power can be charged to an electric vehicle
which requires charging more, even if there are a plurality of
electric vehicles traveling.
{0018}
A charging and billing method according to a second
aspect of the present invention includes a first step of
receiving specific information transmitted from an electric
vehicle, the specific information being for specifying an
owner of the electric vehicle, a second step of receiving a
power supply from a commercial power system and transmitting
8
power for charging a secondary battery from a charging device
arranged at a prescribed position to the electric vehicle
transmitting the specific information, and a third step of
charging a fee to the owner of the electric vehicle specified
with the specific information in accordance with a quantity of
the power transmitted to the electric vehicle by the charging
device.
{Advantageous Effects of Invention}
{0019}
The present invention provides an excellent effect that
simple fee adjustment is possible in accordance with power
transmission from a non-moving charging device to an electric
vehicle.
{Brief Description of Drawings}
{0020}
{Fig. 1}
Fig. 1 is a diagram for illustrating a configuration of
an electric vehicle charging system according to a first
embodiment of the present invention.
{Fig. 2}
Fig. 2 is a functional block diagram for illustrating
functions of a charging device and a managing center in the
electric vehicle charging system according to the first
embodiment of the present invention.
{Fig. 3}
9
Fig. 3 is a flowchart for illustrating a flow of a
charging process according to the first embodiment of the
present invention.
{Fig. 4}
Fig. 4 is a flowchart for illustrating a flow of a
generated surplus power processing process according to the
first embodiment of the present invention.
{Fig. 5}
Fig. 5 is a flowchart for illustrating a flow of a
charging process according to a second embodiment of the
present invention.
{Description of Embodiments}
{0021}
Hereinafter, a description will be given of an embodiment
of an electric vehicle charging system and a charging and
billing method according to the present invention with
reference to the drawings.
{0022}
{First Embodiment}
Hereinafter, a description will be given of a first
embodiment of the present invention.
{0023}
Fig. 1 is a schematic diagram for illustrating an
electric vehicle charging system 10 according to the first
embodiment.
10
The electric vehicle charging system 10 is configured to
include a charging device 12 and a managing center 14 therein,
and the charging device 12 charges a secondary battery 18 of
an electric vehicle 16 (see Fig. 2). Note that the electric
vehicle 16 is not limited to an electric vehicle that is
driven only by power charged to the secondary battery 18, but
may be an automobile that is a hybrid vehicle including a
secondary battery configured to be capable of being charged
externally (plug-in hybrid vehicle).
{0024}
The charging device 12 is arranged at a prescribed
position and receives a power supply from a commercial power
system 20 (see Fig. 2) to transmit the power to the electric
vehicle 16 to charge the secondary battery 18. Note that the
charging device 12 of the first embodiment is arranged along a
road on which the electric vehicle 16 travels, and transmits
power to the electric vehicle 16 on travelling through
wireless power transmission using electromagnetic waves (for
example, microwaves) and the like.
More specifically, the electric vehicle 16 transmits
vehicle information, which will be described in detail later,
in a form of a reference signal. When the reference signal is
received by the charging device 12, wireless power
transmission is performed toward a destination to which the
reference signal is transmitted to charge the secondary
11
battery 18 of the electric vehicle 16.
{0025}
Then, when the power transmission to the electric vehicle
16 is completed, the charging device 12 transmits charging
power quantity information which indicates a quantity of power
transmitted to the electric vehicle 16 to the managing center
14.
{0026}
The managing center 14 performs a billing process based
on the charging power quantity information transmitted from
the charging device 12 to charge an owner of the electric
vehicle 16 (a contractor who can utilize the charging device
12, including an individual and a company) for the charging
fee.
{0027}
Fig. 2 is a functional block diagram for illustrating
functions of the charging device 12 and the managing center 14
in the electric vehicle charging system 10 according to the
first embodiment.
{0028}
The electric vehicle 16 includes a transmitting unit 22
and a power receiving unit 24 in addition to the secondary
battery 18.
{0029}
The transmitting unit 22 transmits vehicle information,
12
which includes residual quantity information indicating a
quantity of residual charged power of the secondary battery 18
and ID (identification) information specific to the electric
vehicle 16, to the charging device 12. Note that the ID
information, which specifies the electric vehicle 16, is
associated with information indicating the owner of the
electric vehicle 16 (for example, name and address of the
owner).
{0030}
The power receiving unit 24 receives power transmitted
from the charging device 12 to charge the secondary battery
18. Note that the electric vehicle 16 receiving power through
wireless power transmission according to the first embodiment
is equipped with the power receiving unit 24 on a roof
thereof.
{0031}
The charging device 12 includes a receiving unit 26 and a
power transmitting unit 28.
{0032}
The receiving unit 26 receives vehicle information from
the electric vehicle 16 and outputs the vehicle information to
the managing center 14.
{0033}
The power transmitting unit 28 receives an input of
charge command, which indicates a quantity of power to be
13
transmitted to the electric vehicle 16, from the managing
center 14 and outputs power to the power receiving unit 24
based on the charge command.
After completion of the power transmission to the
electric vehicle 16, the power transmitting unit 28 outputs
charging power quantity information to the managing center 14.
{0034}
The managing center 14 includes a control device 30 and a
billing device 32.
{0035}
The control device 30 calculates a charge command based
on the residual quantity information included in vehicle
information which is output by the charging device 12, and
outputs the charge command to the charging device 12.
{0036}
The billing device 32 calculates a charging fee to be
charged to the owner of the respective electric vehicle 16
based on charging power quantity information output by the
charging device 12 for each electric vehicle 16. Note that a
charging fee is determined in various ways, for example, a way
in which the fee is calculated by multiplying a quantity of
charging power for each electric vehicle 16 by a prescribed
value once in a month, or a way in which a fixed fee is
employed with no relation to a quantity of charging power.
The managing center 14 charges the owner of the electric
14
vehicle 16 by withdrawing the charging fee from a preregistered
bank account every month, or by issuing a bill for
the charging fee.
{0037}
The control device 30 and the billing device 32 are
composed of a CPU (central processing unit), a RAM (random
access memory), a computer-readable recording medium and the
like, for example. In the recording medium or the like, a
series of processes to execute each function of the control
device 30 and the billing device 32 is recorded in a program
format as an example. The CPU reads the program to the RAM or
the like to execute an information process and arithmetic
operation, whereby the functions are executed.
{0038}
Furthermore, in order to generate power by natural energy
such as solar or wind power, the electric vehicle charging
system 10 according to the first embodiment includes the power
system 20 connected with a solar battery or a wind power
generation apparatus. A power measuring device 34 measuring
power of the power system 20 is provided in a power
transmission network of the power system 20.
When a measurement result is larger than reference power,
the power measuring device 34 outputs surplus power
information, which indicates generation of surplus power in
the power system 20, to the control device 30 included in the
15
managing center 14.
{0039}
Fig. 3 is a flowchart for illustrating a flow of
processes executed by the control device 30 (hereinafter,
referred to as "charging process") in the case where the
electric vehicle 16 is positioned at a charging position where
charging by the charging device 12 is possible, and vehicle
information from the electric vehicle 16 is input to the
control device 30 via the charging device 12.
{0040}
First, at step 100, a charge command is calculated based
on residual quantity information included in the vehicle
information.
{0041}
As a charge command, a command for full charge of the
secondary battery 18 of the electric vehicle 16 which has
transmitted the vehicle information is used, for example.
{0042}
In addition to this, as a charge command, used is a
command for charging the secondary battery 18 so that the
quantity of residual charged power of the secondary battery 18
does not reach or exceed a quantity of charging power
considered not to cause running out of power during a time
period from a start time of the charging to the secondary
battery 18 to a prescribed time (hereinafter, referred to as
16
"predicted quantity of necessary power") based on the quantity
of residual charged power indicated by the residual quantity
information. With this command, the secondary battery 18 of
the electric vehicle 16 is not fully charged, but is charged
with an empty capacity allowing further charging left.
Note that the prescribed time is, for example, a time
when an electricity rate which is lower than that of the other
time periods is started to be applied, that is, when supplies
of midnight electric power are started, and it is at this time
(hereinafter, referred to as "periodical charging start time")
when the secondary battery 18 of the electric vehicle 16 is
charged periodically.
{0043}
Specifically, the predicted quantity of necessary power
is a quantity of power to be charged to the secondary battery
18 in order to prevent running out of power even if the
electric vehicle 16 runs until the periodical charging start
time.
Note that the predicted quantity of necessary power is
calculated based on power consumption information which
indicates temporary change of the past power consumption
quantities of the electric vehicle 16. The power consumption
information indicates the temporary change of the past power
consumption quantities of the electric vehicle 16. Based on
the residual quantity information transmitted from electric
17
vehicles 16, the power consumption information for each
electric vehicle 16 is stored in a storing means (not
illustrated) included in the control device 30.
{0044}
In order to calculate the predicted quantity of necessary
power, the control device 30 calculates a mean value of the
past power consumption quantities (for example, for the last
few years) during a time period from the start time of the
charging to the secondary battery 18 to the periodical
charging start time, and a dispersion value of the past power
consumption quantities during the time period, based on the
stored power consumption information. Then, the control
device 30 calculates the predicted quantity of necessary power
based on the calculated mean value and dispersion value.
Note that the start time of the charging to the secondary
battery 18 is a time when the electric vehicle 16 gets
positioned at the charging position for the charging, that is,
when the vehicle information is transmitted from the electric
vehicle 16 to the charging device 12. In the following
description, "the start time of the charging to the secondary
battery 18" is also referred to as "current time".
{0045}
In the first embodiment, a standard deviation is used as
the dispersion value. In addition, in the first embodiment,
3σ is used as the standard deviation, but the standard
18
deviation is not limited to this and may be σ, 2σ, 4σ or the
like. With the use of the standard deviation of 3σ, a
predicted quantity of necessary power is calculated with the
case where the power consumption quantity of the electric
vehicle 16 suddenly becomes excessive taken into
consideration.
{0046}
Formula (1) below is an exemplary arithmetic expression
for calculating the predicted quantity of necessary power
using Bayes' theorem. In Formula (1), a best estimate of a
temporary density of power consumption quantities in a time
period from a current time t1 to a periodical charging start
time t2 and a standard deviation of the temporary density of
power consumption quantities as of the time, the day of a
week, the date, the month concerned are added together to
calculate a predicted quantity of necessary power.
Note that the best estimate is a conditional probability
distribution, more specifically, a mean value of the time
period from the current time t1 to the periodical charging
start time t2 of the day of a week, the date, and the month
concerned.
19
{0047}
Based on the quantity of residual charged power indicated
by the residual quantity information and the predicted
quantity of necessary power, the control device 30 calculates
a charge command for changing a power transmitting timing or
power to be transmitted.
Specifically, if the quantity of residual charged power
is equal to or larger than the predicted quantity of necessary
power, for example, the control device 30 calculates a charge
command for delaying power transmission, that is, a charge
command for inhibiting on-the-spot power transmission (the
power transmission time period of 0 (zero) hours).
Furthermore, if the quantity of residual charged power is
lower than the predicted quantity of necessary power but equal
to or larger than a prescribed ratio of the predicted quantity
of necessary power (for example, 70%), rapid charge of the
secondary battery 18 is not needed, and therefore, the control
device 30 calculates a charge command for transmitting power
equal to or lower than a reference value (for example, 50%).
20
If the quantity of residual charged power is equal to or lower
than the prescribed ratio, the control device 30 calculates a
charge command for transmitting power of the reference value.
In this way, a charge command includes power to be
transmitted and a power transmission time period, for example.
{0048}
At the subsequent step 102, the calculated charge command
is output to the charging device 12.
When the charging device 12 receives an input of the
charge command, the charging device 12 transmits power to the
electric vehicle 16 which has transmitted the vehicle
information, based on the power to be transmitted and power
transmission time period which are indicated by the charge
command. Consequently, the charging to the secondary battery
18 of the electric vehicle 16 is performed without reception
of the fee on the spot.
When the power transmission to the electric vehicle 16 is
completed, the charging device 12 outputs charging power
quantity information to the control device 30.
{0049}
At the subsequent step 104, the process is in a wait
state until input of the charging power quantity information
output from the charging device 12, and when the charging
power quantity information is input to the control device 30,
the process proceeds to step 106.
21
{0050}
Note that the charging power quantity information may be
a quantity of power transmitted to the electric vehicle 16 by
the charging device 12 as it is or a quantity of power
actually charged to the secondary battery 18 of the electric
vehicle 16. The quantity of power actually charged to the
secondary battery 18 can be obtained by the electric vehicle
16 transmitting the residual quantity information sequentially
to the charging device 12 to calculate a difference between
the quantities of residual charged power before and after the
power transmission.
{0051}
At step 106, based on the quantity of power indicated by
the charging power quantity information, the billing device 32
calculates a charging fee charged to the owner who is
indicated by the ID information included in the vehicle
information. Note that if a monthly fixed rate system is
applied to the charging fee, for example, a process
corresponding to the fixed rate system is executed (for
example, only date and time of charging and a quantity of
power used are stored).
{0052}
Completion of the process of step 106 ends the charging
process.
{0053}
22
In the electric vehicle charging system 10 according to
the first embodiment, when surplus power is generated in the
power system 20 from which the charging device 12 receives a
power supply, power transmission to the electric vehicle 16 is
performed.
Generation of surplus power is detected through input of
surplus power information from the power measuring device 34
to the control device 30.
{0054}
Power generated by natural energy such as solar or wind
power may excessively increase due to instability of natural
energy. In this case, when surplus power that has excessively
increased is not consumed, a power generation quantity has
been suppressed and consumed wastefully.
Thus, according to the electric vehicle charging system
10 of the first embodiment, when surplus power is generated in
the power system 20, the power is charged to the secondary
battery 18 of the electric vehicle 16, and the surplus power
generated in the power system 20 can be thereby utilized
without any waste.
{0055}
Fig. 4 is a flowchart for illustrating a flow of
processes executed by the control device 30 (hereinafter,
referred to as "generated surplus power processing process")
in the case where surplus power information is input to the
23
control device 30.
{0056}
First, at step 200, it is determined whether the electric
vehicle 16 is positioned at a charging position where power
transmission by the charging device 12 is possible. In the
case of positive determination, the process proceeds to step
202, while in the case of negative determination, the
generated surplus power processing process ends.
Note that the determination processing at step 200 is
executed according to whether vehicle information is input to
the control device 30 via the charging device 12 or not.
Specifically, when the control device 30 is in the state of
receiving an input of the vehicle information, it is
determined that the electric vehicle 16 is positioned at the
charging position.
{0057}
At step 202, a charge command for full charge of the
secondary battery 18 of the electric vehicle 16 is calculated.
The reason why the charge command is calculated here for full
charge is to consume the surplus power as much as possible.
As previously described, the quantity of residual charged
power of the secondary battery 18 of the electric vehicle 16
is made not to reach or exceed the predicted quantity of
necessary power, whereby making sure the empty capacity of the
secondary battery 18 left. Accordingly, when surplus power is
24
generated, a more quantity of the surplus power can be used
for charging.
{0058}
For the charge command, the control device 30 may
calculate a command for increasing power transmitted to the
electric vehicle 16. If calculated so, when surplus power is
generated in the power system 20, more power is charged to the
secondary battery 18 of the electric vehicle 16, and thus, the
surplus power generated in the power system 20 can be utilized
without any waste.
For example, if a quantity of power transmitted in a
normal case with no surplus power generated is assumed to be
100 W, a quantity of power transmitted in a case with surplus
power generated is 150 W.
{0059}
At the subsequent step 204, the calculated charge command
is output to the charging device 12.
{0060}
At the subsequent step 206, the process is in a wait
state until input of the charging power quantity information
output from the charging device 12, and when the charging
power quantity information is input to the control device 30,
the process proceeds to step 208.
{0061}
At step 208, the billing device 32 calculates a charging
25
fee to be charged to an owner indicated by ID information
included in the vehicle information, based on the quantity of
power indicated by the charging power quantity information,
and then the charging process ends.
{0062}
As described so far, the electric vehicle charging system
10 according to the first embodiment includes the charging
device 12 having the receiving unit 26 receiving specific
information transmitted from the electric vehicle 16, the
specific information being for specifying the owner of the
electric vehicle 16, and the power transmitting unit 28
receiving a power supply from the commercial power system 20
and transmitting power for charging the secondary battery 18
to the electric vehicle 16 transmitting the specific
information, the charging device 12 arranged at the prescribed
position, and the billing device 32 charging a fee to the
owner of the electric vehicle specified with the specific
information in accordance with a quantity of the power
transmitted to the electric vehicle 16 by the charging device
12.
Consequently, in the electric vehicle charging system 10
according to the first embodiment, simple fee adjustment is
possible in accordance with power transmission from a nonmoving
charging device to an electric vehicle.
{0063}
26
{Second Embodiment}
Hereinafter, a description will be given of a second
embodiment of the present invention.
{0064}
Note that the configuration of an electric vehicle
charging system 10 according to the second embodiment is same
as that of the electric vehicle charging system 10 according
to the first embodiment illustrated in Fig. 1 and Fig. 2, and
therefore a description thereof is omitted.
{0065}
In the second embodiment, a description will be given of
a case where the charging device 12 arranged along a road on
which the electric vehicle 16 travels transmits power to a
plurality of the electric vehicles 16 traveling on the road.
{0066}
Fig. 5 is a flowchart for illustrating a flow of a
charging process according to the second embodiment. Note
that a step in Fig. 5 same as that in Fig. 3 is denoted by the
same reference sign, and part or all of a description thereof
is omitted.
{0067}
First, at step 300, it is determined whether a plurality
of the electric vehicles 16 are positioned at a charging
position where power transmission by a single charging device
12 is possible. In the case of positive determination, the
27
process proceeds to step 302, while in the case of negative
determination, the process proceeds to step 100. The
determination processing at step 300 is to determine whether a
plurality of pieces of vehicle information are input to the
control device 30 via the charging device 12 or not.
{0068}
At step 302, a charge command is calculated for each
electric vehicle 16 corresponding to the respective input
pieces of vehicle information.
{0069}
At step 302, the control device 30 calculates a charge
command for each electric vehicle 16 based on residual
quantity information included in the piece of vehicle
information for each electric vehicle 16 so as to change each
proportion of time periods used for wireless power
transmission from the charging device 12, and then the process
proceeds to step 102.
{0070}
Specifically, the control device 30 calculates a charge
command so that the larger proportion of time periods for
wireless power transmission is allocated to an electric
vehicle 16 with the lower quantity of residual charged power
indicated by the residual quantity information.
{0071}
If a charge command is input to the charging device 12,
28
the charging device 12 rotates and moves the power
transmitting unit 28 so as to transmit power to each electric
vehicle 16 at the proportion of time periods (by time
division) based on the charge command.
{0072}
Power is therefore transmitted with priority to the
electric vehicle 16 with the lower quantity of residual
charged power, and thus, the electric vehicle charging system
10 according to the second embodiment enables charging to the
electric vehicle 16 which requires charging more, even if
there are a plurality of electric vehicles 16 traveling.
{0073}
Also in the second embodiment, as in the first
embodiment, based on the quantity of residual charged power
indicated by the residual quantity information and the
predicted quantity of necessary power, a charge command for
changing a power transmitting timing or power to be
transmitted may be calculated for each of the plurality of
electric vehicles 16.
{0074}
As above, the present invention is described with the
aforementioned embodiments, but the technical scope of the
present invention is not limited to the scope of the
aforementioned embodiments. Various modifications and
improvements of the aforementioned embodiments are possible
29
within the scope of the present invention. The technical
scope of the present invention also includes an embodiment in
which such a modification or improvement is made.
{0075}
In the aforementioned embodiments, the descriptions are
given of the embodiment in which the charging device 12 is
arranged along the road, but the present invention is not
limited to this embodiment, and thus, an embodiment may be
employed in which the charging device 12 is arranged
adjacently to a commercial temporally or monthly parking lot
or a parking lot of a commercial facility, and an embodiment
may be employed in which the charging device 12 is arranged
adjacently to a parking space of a general house, for example.
{0076}
Moreover, in the aforementioned embodiments, the
descriptions are given of the embodiment in which a charge
command is calculated by the managing center 14 which is not
the charging device 12, but the present invention is not
limited to this embodiment, and thus, an embodiment may be
employed in which a charge command is calculated by the
charging device 12 and an billing process is performed by the
managing center 14.
{0077}
Furthermore, the respective flows of the processes
described in the aforementioned embodiments are also an
30
example, and elimination of an unnecessary step, addition of a
new step, and exchange of process order are possible without
departing from the scope of the present invention.
{Reference Signs List}
{0078}
10 electric vehicle charging system
12 charging device
14 managing center
16 electric vehicle
20 power system
26 receiving unit
28 power transmitting unit
32 billing device

{CLAIMS}
{Claim 1}
An electric vehicle charging system comprising:
a charging device having a receiving means receiving
specific information transmitted from an electric vehicle, the
specific information being for specifying an owner of the
electric vehicle, and a power transmitting means receiving a
power supply from a commercial power system and transmitting
power for charging a secondary battery to the electric vehicle
transmitting the specific information, the charging device
being arranged at a prescribed position; and
a billing device charging a fee to the owner of the
electric vehicle specified with the specific information in
accordance with a quantity of the power transmitted to the
electric vehicle by the charging device.
{Claim 2}
The electric vehicle charging system according to claim
1, wherein when surplus power is generated in the power system
from which the charging device receives a power supply, the
charging device transmits power to the electric vehicle.
{Claim 3}
The electric vehicle charging system according to claim 1
or 2, wherein when surplus power is generated in the power
system from which the charging device receives a power supply,
the charging device increases power to be transmitted to the
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electric vehicle.
{Claim 4}
The electric vehicle charging system according to any one
of claims 1 to 3, wherein the electric vehicle transmits to
the charging device residual quantity information indicating a
quantity of residual charged power of the secondary battery
along with the specific information, and
the charging device, based on the quantity of residual
charged power indicated by the residual quantity information,
changes a power transmitting timing or power to be transmitted
to charge the secondary battery so that the quantity of
residual charged power of the secondary battery of the
electric vehicle does not reach or exceed a quantity of
charging power considered not to cause running out of power
during a time period from a start time of the charging to the
secondary battery to a prescribed time.
{Claim 5}
The electric vehicle charging system according to any one
of claims 1 to 4, wherein the electric vehicle transmits to
the charging device residual quantity information indicating a
quantity of residual charged power of the secondary battery
along with the specific information, and
the charging device is arranged along a road on which the
electric vehicle travels, and changes a proportion of time
periods used for wireless power transmission for a plurality
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of the electric vehicles travelling on the road based on the
residual quantity information.
{Claim 6}
A charging and billing method comprising:
a first step of receiving specific information
transmitted from an electric vehicle, the specific information
being for specifying an owner of the electric vehicle;
a second step of receiving a power supply from a
commercial power system and transmitting power for charging a
secondary battery from a charging device arranged at a
prescribed position to the electric vehicle transmitting the
specific information; and
a third step of charging a fee to the owner of the
electric vehicle specified with the specific information in
accordance with a quantity of the power transmitted to the
electric vehicle by the charging device.