JP2012137420A - Route search device, route search method and computer program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an occupant of an electric vehicle with a relay route having a short waiting time at a charge point.SOLUTION: A route search device 1 searches for a relay route leading to a destination via a relay point P1, P2 where a charge point is located. The route search device 1 has a cost setting part 2A for setting a waiting cost associated with a waiting time at a charge point, and a route search part 2B for searching for a relay route with the set waiting cost included in a link cost.

Description

  The present invention relates to a route search device for searching for a route suitable for an electric vehicle to travel from a departure place to a destination, a route search method and a computer program thereof, and a route search method in consideration of a waiting time at a charging point. Is to provide.

A route search device that is mounted on an automobile driven by an internal combustion engine and searches for an optimum route from a starting point to a destination has already been put into practical use. However, currently commercially available route search devices are not premised on installation in electric vehicles, and no particular consideration is given to the cruising distance and charging time specific to electric vehicles.
Therefore, even if an optimum route is searched by a normal route search device, an electric vehicle may not reach the destination because the cruising distance is shorter than that of an internal combustion engine vehicle.

  Therefore, as a route search device for an electric vehicle, when the route to the destination exceeds the cruising distance of the electric vehicle, a search is made for another route via a charging point (also referred to as “charging station”). An electric vehicle route search device that provides a route that can reliably reach a destination has been proposed (see Patent Document 1).

JP-A-10-170293

However, since the route search device described in Patent Document 1 does not consider the congestion status and reservation status at the charging point, when the driver adopts a route that passes through the charging point searched by the route search device, the charging is performed. It may take an unexpected time to wait until the charging starts at the point, and the destination may not be reached as scheduled.
In view of the above-described conventional problems, an object of the present invention is to provide a route search device and the like that can provide a relay route with a small waiting time at a charging point to a passenger of an electric vehicle.

  (1) A route search device according to the present invention is a route search device that searches for a relay route to a destination via a relay point with a charging point, and has a waiting cost corresponding to the waiting time at the charging point. A cost setting unit for setting, and a route searching unit for searching for the relay route by including the set standby cost in a link cost.

According to the route search device according to the present invention, the cost setting unit sets a standby cost corresponding to the waiting time at the charging point, and the route search unit includes the set standby cost in the link cost as a relay route. Therefore, it is possible to search for a relay route with as little waiting time as possible at the charging point.
For this reason, by providing the occupant with the searched relay route through an output device such as an on-vehicle display, the waiting time at the charging point is small (including the case where the waiting time before starting charging is zero). ) It is possible to guide the relay route in advance to the passenger.

(2) In the route search device according to the present invention, the cost setting unit can set the standby cost based on, for example, a statistical value of a past waiting time at the charging point.
In this case, for example, relatively accurate cost setting is possible without collecting information on the current reservation status of the charging point, which is necessary when accurately obtaining the estimated waiting time at the time of arrival described later, The route search apparatus according to the present invention can be realized easily and inexpensively.

(3) Further, in the route search device according to the present invention, the cost setting unit may set the standby cost based on a current full state at the charging point.
However, if the standby cost is set based on the current full availability, if the charging point is far away and it takes a relatively long time for the vehicle to arrive at the charging point, There is a risk that it will not be available when the vehicle arrives.

(4) Therefore, in the route search device according to the present invention, the cost setting unit sets the waiting cost based on a predicted waiting time at the time of arrival of the own vehicle estimated from a current reservation state of the charging point. It is preferable.
In this case, since the waiting time is included in the waiting time for the estimated waiting time at the arrival of the vehicle estimated from the current reservation status, the relay route is searched, so the relay including the charging point with a surely low waiting time at the arrival time. The route can be searched.

(5) In addition, as described above, in the case of a route search device that estimates the estimated waiting time at the time of arrival of the vehicle from the current reservation status of the charging point, the charging point that passes through the searched relay route It is preferable to further include a reservation notifying unit for making a reservation at the charging point when the charging point is empty at the estimated arrival time.
In this case, since the reservation notifying unit makes a reservation at the charging point, the charging facility can be used reliably when the host vehicle arrives at the charging point, and waiting time can be eliminated.

(6) However, if the reservation notifying unit does not arrive at the estimated arrival time after making a reservation at the charging point, it performs at least one of the following (a) and (b). It is preferable.
(A) 1st process which performs again the cost setting by a cost setting part, and the search process by a route search part (b) 2nd process which changes the reservation with respect to a charging point

  If the first process (a) is performed, the estimated waiting time at the time of arrival of the host vehicle estimated from the new reservation status is set again as the standby cost, and the new standby cost is included in the link cost. Since the search for the relay route is performed again, it is possible to provide the passenger with a relay route in consideration of the latest reservation status.

  “Reservation change” in the second process (b) includes both a change of the reservation time and a cancellation of the reservation. If this second process is performed, for example, if it is found that the vehicle arrives earlier than the estimated arrival time, the reservation time for using the charging point is advanced, or conversely, the own vehicle is estimated to arrive. If it is found that the vehicle arrives later than that, it is possible to efficiently use the charging facility at the charging point by delaying the reservation time or canceling the reservation.

(7) The route search method according to the present invention is a method performed by the route search device according to the present invention, and has the same effects as the route search device.
(8) The computer program according to the present invention is a program for causing a computer to execute each step of the route search method according to the present invention, and has the same effects as the route search method.

  As described above, according to the present invention, a relay route with a low waiting time at a charging point can be provided to a passenger of an electric vehicle.

It is a block diagram which shows the whole structure of the route search apparatus which concerns on 1st Embodiment. It is a figure which shows an example of the reference table regarding the statistical value of the waiting time of a charging point. It is a figure which shows an example of the input setting screen by a display. It is a flowchart (first half) which shows the processing content of a vehicle-mounted computer. It is a flowchart (latter half) which shows the processing content of a vehicle-mounted computer. It is an example of a route map when a relay point with a charging point is selected. It is a block diagram which shows the whole structure of the route search apparatus which concerns on 2nd Embodiment. It is a figure which shows an example of the reference table regarding the reservation status of a charging point. It is a figure which shows an example of the reference table regarding the full empty condition of a charging point.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
[Overall configuration of route search device]
FIG. 1 is a block diagram showing an overall configuration of a route search apparatus 1 according to the first embodiment.
The route search apparatus 1 performs a route search suitable for an electric vehicle (hereinafter sometimes abbreviated as “vehicle”) 20 and performs the route search and operation control of each electronic device in the vehicle. It has the vehicle-mounted computer 2 which is an electronic controller.

  Connected to the in-vehicle computer 2 are a GPS receiver 3, a vehicle speed sensor 4, a gyro sensor 5, a storage device 6, a display 7, a speaker 8, an input device 9, a wireless communication device 10, and a battery control unit 11.

The GPS receiver 3, the vehicle speed sensor 4, and the gyro sensor 5 are sensors that grasp the traveling position, speed, and direction of the electric vehicle 20.
The in-vehicle computer 2 obtains the absolute position of the own vehicle based on GPS signals periodically acquired by the GPS receiver 3 and interpolates the position and direction based on input signals input from the vehicle speed sensor 4 and the gyro sensor 5 as needed. Thus, the accurate current position and direction of the vehicle 20 are always grasped.

The storage device 6 includes a map database. This map database provides road map data to the in-vehicle computer 2, and the road map data includes link data and node data, and is stored in a recording medium such as a DVD. The road map data includes the position of a charging point that can supply power to the electric vehicle 20.
The storage device 6 reads out necessary road map data from the recording medium in response to a command from the in-vehicle computer 2 and provides it to the computer 2. As the recording medium, various recording media such as a CD-ROM, a memory card, and a hard disk can be employed in addition to the DVD.

The display 7 and the speaker 8 are used to present various information generated by the in-vehicle computer 2 to the passenger of the vehicle 20. Specifically, the display 7 displays an input setting screen for route search, a map image around the host vehicle, route information to the destination, and the like, and the speaker 8 guides the host vehicle to the destination. Output announcements as audio.
In the present embodiment, the in-vehicle computer 2 determines the setting state of the electrical equipment that can be used while traveling on the searched route (direct route and relay route described later), but the determined setting state is also displayed on the display 7. Is displayed.

The input device 9 is for the driver of the vehicle 20 to make various inputs related to route search.
Specifically, the input device 9 is composed of a combination of various input means such as an operation switch provided on the steering wheel, a joystick, or a touch panel provided on the display 7. Note that a voice recognition device that accepts input by voice recognition of the driver may be the input device 9. An input signal sent by the driver to the input device 9 is sent to the in-vehicle computer 2.

The wireless communication device 10 acquires various types of provision information from the information center 23 through wireless communication with the information center 23.
That is, the wireless communication device 10 accesses the information center 23 using the mobile communication network 21 according to a command from the in-vehicle computer 2, and when provided information such as traffic jam information is transmitted from the information center 23, the provided information is Receive and notify the in-vehicle computer 2. The provided information received from the information center 23 includes charging point waiting time information, which will be described later.

The in-vehicle computer 2 is composed of, for example, an arithmetic processing device such as a microcomputer in which various control programs are installed. By executing the control program, a function for displaying a map image on the display 7, from a departure place to a destination place. Various navigation functions such as a function for calculating a route (including the position when there is a relay point) and a function for guiding the vehicle 20 to the destination according to the route can be executed.
The in-vehicle computer 2 of the present embodiment also has a function of determining whether or not the vehicle 20 can arrive at the current remaining battery capacity when a route to the destination is searched.

  The in-vehicle computer 2 is configured by installing a predetermined computer program for realizing each of the above functions, and this program can be stored in a recording medium such as a CD-ROM or a DVD-ROM for sale or transfer. it can. The program may be sold or transferred by downloading it from a server computer via a network.

The battery control unit 11 is communicably connected to the in-vehicle computer 2 via a communication cable in the vehicle, and controls the charging / discharging operation of the battery while monitoring the power state of the battery of the own vehicle. The in-vehicle computer 2 acquires information on the remaining battery capacity at the present time from the battery control unit 11 when performing a route search.
The storage device 6 uses the average power consumed by the electric motor, which is a travel drive source, while the vehicle travels a unit distance (for example, 1 km) as data for calculating the travel power required for the travel of the host vehicle. The amount is stored for each road type such as when driving on a general road or driving on a highway.

[Road map data in the map database]
The road map data of the map database includes “link data” and “node data”. Among these, “node data” is data in which an intersection ID is associated with an intersection position. Further, the “link data” includes data in which the following information 1) to 4) is associated with the link ID of the specific link.
1) Position of start point / end point / interpolation point of specific link 2) Link ID connected to start point of specific link
3) Link ID connected to the end point of a specific link
4) Link cost of a specific link

  The map database includes a road type indicating whether the link corresponding to each road on the map is a general road or a toll road, a toll in the case of a toll road, and a station ID of a charging point that can supply power to the electric vehicle 20. That position is also included.

The above “link cost” is prepared, for example, by the number of combinations of the specific link and the link connected to the end point. After entering the start point of the specific link, the end point of the specific link is exited and then connected. Includes the “link travel time” required to enter the starting point of the link.
That is, the link cost includes the “link transit time” required to travel from the start point to the end point of a specific link and the time cost required to travel from the end point of the specific link to the start point of the next link, that is, “Intersection passing time” required for passing the intersection is included.

For the above link travel time, data for every 5 minutes from the current day to the next day is prepared for each day type such as weekdays, Saturdays, Sundays and holidays, and this data is obtained from the Traffic Information Center. Possible VICS ("VICS" is a registered trademark of Japan Road Traffic Information Center) information and probe information acquired from other vehicles are created.
In this embodiment, not only the link travel time but also the “standby cost” corresponding to the waiting time at the charging point is included in the link cost, and the details of the setting method will be described later.

The in-vehicle computer 2 of the present embodiment includes a cost setting unit 2A and a route searching unit 2B as function realizing units realized by executing the control program.
Among these, when the route search unit 2B searches for a relay route via the charging point, the cost setting unit 2A sets a “standby cost” corresponding to a waiting time until the charging of the electric vehicle 20 at the charging point is started. Has the function to set. The route search unit 2B has a function of searching for a relay route by including the set standby cost in the link cost.

Note that the optimum relay route searched by the route search unit 2B is output to the display 7 and displayed on the screen thereof, whereby the relay route is provided to the passenger.
Specifically, the computer program constituting the route search unit 2B includes route search logic by the Dijkstra method or the potential method. In other words, the route search unit 2B of the present embodiment can search for a recommended route that minimizes the cumulative total of link costs from the departure point to the destination by executing a program including the route search logic.

Here, in the Dijkstra method, when a link tree starting from a search start link is constructed, when branching from a certain link to a plurality of links, the path cost of the link of each branch (from the search start link to the link). A method is used in which the sum of the link costs) is compared and rearranged in ascending order of the route cost, and the search is further continued from the link with the lower route cost.
Therefore, when the search end link is reached first, the path with the lowest cost that reaches the search end link at that time is determined. This is because the search is performed in order from the link with the lowest link cost, and the route that has reached the search end link first becomes the route with the lowest cost as it is.

On the other hand, in the potential method, when branching from one link to multiple links, all links are treated equally and the search is further performed from the links of each branch without comparing the path costs of the links of each branch. The method of continuing is adopted.
Therefore, even if the search end link is reached first, there is still a possibility of reaching the search end link through another route at that time, so when all the links in the network have been searched For the first time, the least cost route to reach the search end link is determined.

〔Information Center〕
As shown in FIG. 1, the information center 23 includes a wireless communication device 24, a center computer 25, and a storage device 26. The wireless communication device 24 can communicate with the wireless communication device 10 of each vehicle 20 and a communication device (not shown) provided at charging points throughout Japan or in a predetermined region via the mobile communication network 21. .
The center computer 25 collects the waiting time for each time zone generated in the past at the charging point from each charging point.

  In this embodiment, the “waiting time” collected from each charging point is the waiting time required to start charging the electric vehicle 20 after arriving at the charging point (hereinafter referred to as “starting waiting time”). Is).

The center computer 25 classifies statistical values (for example, average value and median value) of the waiting time data of each charging point into time zones of day types such as weekdays, Saturdays, Sundays, and holidays and collects them in the reference table 22A. It is stored in the storage device 26. FIG. 2 is a diagram showing an example of the reference table 22A.
As shown in FIG. 2, the reference table 22A is composed of a table group of day types. Each table on a specific day has a predetermined time (3 hours in the example) for each station number for identifying a charging point. The statistical value of the start waiting time for each time zone divided by) is written.

According to the reference table 22A illustrated in FIG. 2, for example, the statistical value of the start waiting time at the charging point with the station number “1” is “0” from 0 o'clock to 3 o'clock (the unit is time, and so on). It is “0” from 3 o'clock to 6 o'clock, “0.1” from 6 o'clock to 9 o'clock, “0.5” from 9 o'clock to 12 o'clock, and “1.5” from 12 o'clock to 15 o'clock .
The statistical value of the start waiting time at the charging point with the station number “2” is “0” from 0:00 to 3:00, “0” from 3:00 to 6:00, and “0.2” from 6:00 to 9:00. ”Is“ 1.0 ”from 9 o'clock to 12 o'clock and“ 0.5 ”from 12 o'clock to 15 o'clock.

The center computer 25 distributes the reference table 22A stored in the storage device 26 to the electric vehicle 20 by including in the downlink information every predetermined period. The in-vehicle computer 2 of the electric vehicle 20 that has received this extracts the reference table 22A from the downlink information and stores it in the storage device 6 of the own vehicle.
Note that the reference table 22A of FIG. 2 is a table of statistical values of past start waiting times, and therefore the center computer 25 does not necessarily need to automatically distribute.

For example, when the reference table 22A is disclosed on the website of the information center 23, a passenger who desires it may download the reference table 22A through the Internet and store it in the storage device 6.
Moreover, the vehicle-mounted computer 2 of the vehicle 20 may collect data from each charging point, so that each vehicle 20 autonomously creates the reference table 22A and stores it in the storage device 6 of the own vehicle.

[Display input setting screen]
FIG. 3 is a diagram showing an example of an input setting screen by the display 7.
As shown in FIG. 3, on the input screen of the display 7, a “position input icon” for a departure point and a destination, and a “priority setting icon” for selecting one of high speed priority, time priority, and charge priority are selected. In addition, a “search type icon” for selecting whether or not to search for a relay route via a charging point is displayed.

  When the passenger of the vehicle 20 selects “with charging point” on the right side of the “search type icon”, the in-vehicle computer 2 of the present embodiment searches for a route including the “relay route” via the charging point, When “no charging point” is selected, a search is made only for the “direct route” that goes straight to the destination without going through the charging point.

[Processing content of in-vehicle computer]
4 and 5 are flowcharts showing the processing contents of the in-vehicle computer 2.
Hereinafter, a route search method for the electric vehicle 20 performed by the in-vehicle computer 2 in the first embodiment will be described with reference to this flowchart.
<Direct route search processing>
As shown in FIG. 4, the route search unit 2B of the in-vehicle computer 2 first reads the departure place and destination input by the passenger on the input operation screen of the display 7 (step ST1).

When the passenger does not input “departure place” on the input operation screen, the “current position” obtained by the GPS receiver 3 is set as the departure place.
Thereafter, the route search unit 2B uses the predetermined route such as the Dijkstra method or the potential method as the “direct route” that minimizes the link cost when the vehicle 20 goes straight without charging from the departure point to the destination. Search is performed by search logic (step ST2).

That is, the route search unit 2B uses the link or node closest to the departure point as the search start link, and the link closest to the destination as the search end link. From the link data to the search start link to the search end link. The included network data is acquired from the map database of the storage device 6, and the route search logic is executed on this network data.
More specifically, links from the search start link to the search end link are sequentially added to form a link tree, and the tree reaching the search end link is defined by the following expression (1). The direct route with the lowest link cost is obtained by route search logic using the Dijkstra method or the potential method.

Link cost = (a x Link travel time)
+ (B x link distance)
+ (C x road type)
+ (D x toll)
+ (E x intersection transit time)
+ (F x standby cost) ... (1)

  Note that a to f in the above formula (1) are coefficients set for each route calculation type, and in the case of step ST2 in FIG. 4 for searching for an “direct route” that does not pass through a charging point, a cost setting unit. 2A sets the coefficient of the standby cost to “0”.

Next, the route search unit 2B of the in-vehicle computer 2 reads the current battery remaining capacity Wo (step ST3), and calculates the travel power Wr necessary to travel through the direct route to the destination (step ST4). .
The travel power Wr can be calculated by multiplying the average power amount per unit distance consumed by the electric motor by the cumulative distance of the direct route.

Thereafter, the route search unit 2B determines whether or not the remaining battery capacity Wo is equal to or greater than the traveling power Wr (step ST5). If the determination result is affirmative, the direct route that is the search result is displayed. 7 (step ST6).
On the other hand, when the determination result is negative, that is, when the remaining battery capacity Wo is less than the traveling power Wr, the searched direct route cannot reach the destination, so the process proceeds to the relay route search process shown in FIG. .

  In the input operation screen shown in FIG. 3, when the user (passenger of the vehicle 20) selects “no charging point” as the “search type”, even if the determination result in step ST5 is negative, FIG. The display 7 displays that there is no direct route that can be reached to the departure place without shifting to the search process 5.

<Relay route search processing>
In the relay route search process shown in FIG. 5, the route search unit 2B of the in-vehicle computer 2 first selects a relay point with a charging point (step ST6).
Note that this selection process can be performed, for example, by sequentially detecting charging points within a predetermined radius (for example, 10 km) with the link node included in the direct route as the center.

Next, the cost setting unit 2A of the in-vehicle computer 2 sets the standby cost for the selected one or more charging points (step ST8).
FIG. 6 shows an example of a route diagram when the relay points P1 and P2 with the charging point are selected. In this example, it is assumed that two relay points P1 and P2 are selected in step ST7, and the following two types of routes are assumed on condition that the relay points P1 and P2 are routed.
(A) Ps → P1 → Pd
(B) Ps → P2 → Pd

Further, it is assumed that the relay point P1 is station number 1 in FIG. 2 and the predicted arrival time at the relay point P1 is 12:30, the relay point P2 is station number 2 in FIG. 2, and the arrival at the relay point P2 Assume that the predicted time is 13:30.
In this case, according to the reference table 22A of FIG. 2, each of the predicted arrival times is included in the time zone from 12:00 to 15:00.

  Therefore, the cost setting unit 2A of the in-vehicle computer 2 sets the station number “1” and the time zone from 12:00 to 15:00 from the data (statistic value of the start waiting time) in the reference table 22A of FIG. “1.5” included, and “0.5” included in the time zone with the station number “2” and 12:00 to 15:00 are extracted, and these data values are accumulated formulas of link costs. Set to “standby cost” in (1).

Thereafter, the route search unit 2B of the in-vehicle computer 2 uses the set standby cost to determine a “relay route” that minimizes the link cost when traveling to the destination Pd via the relay points P1 and P2. Search is performed by the predetermined search logic (step ST9).
That is, the route search unit 2B sets the standby cost of the equation (1) to “1.5” for the route (a) that is conditional on the route P1, and the equation (1) for the route (b) that is conditional on the route P2. The waiting route of (1) is set to “0.5”, and the relay route having the smallest cumulative link cost defined by equation (1) in the tree leading to the search end link is selected as a route by the Dijkstra method or the potential method. Obtained by search logic.

Next, the route search unit 2B calculates the travel power Wr (j) necessary for traveling through the identified optimum relay route to the destination Pd for each section constituting the relay route (step ST10). .
Here, “j” in step ST10 indicates the section number assigned to each section in FIG. 6, and in the example of FIG. 6, the section from Ps to P1 is j = 1, the section from P1 to Pd is j = 2, The section from Ps to P2 is j = 3, and the section from P2 to Pd is j = 4.

  For example, assuming that the relay route identified as the optimum route is the route (b) of Ps → P2 → Pd, the route search unit 2B sets the section number to the average power amount per unit distance consumed by the electric motor. By multiplying the cumulative distance of each section of j = 3 and section number i = 4, the traveling power Wr (3), Wr (4) for each section is calculated.

Next, the route search unit 2B determines whether or not the current remaining battery capacity W0 or the charged battery capacity Wmax is equal to or greater than the travel power Wr (j) of each section (step ST11).
Note that {W0, Wmax} in step ST11 is the section where the current remaining battery capacity W0 is applied when the section start point is the starting point Ps and the section start point is the relay point P1, P2. In the case of the number j, it means that the remaining battery capacity Wmax after charging is applied.

Therefore, if the identified relay route is the route (b), the route search unit 2B determines whether or not the current remaining battery capacity Wo is equal to or greater than the traveling power W (3), and after charging. It is determined whether or not the remaining battery capacity Wmax is equal to or greater than the traveling power W (4).
Note that the remaining battery capacity Wmax after charging does not necessarily have to be the remaining battery capacity in the case of full charge, but may be a capacity that can ensure a cruising distance of a predetermined distance (for example, 50 km).

When the above determination result is affirmative, the route search unit 2B outputs the relay route that is the search result to the display 7 (step ST12), and this route is provided to the passenger by the screen display of the display 7. The
On the other hand, if the determination result is negative, that is, the remaining battery capacity Wo is less than the running power W (3) or the battery capacity Wmax after charging is less than the running power W (4), the route search unit 2B Since the search result relay route cannot arrive at the destination Pd, an output indicating that there is no route that can reach the destination Pd is output including the case of the direct route (step ST13).

As described above, according to the route search device 1 of the first embodiment, the cost setting unit 2A of the in-vehicle computer 2 sets the statistical value of the past start waiting time at the charging point (relay point P1, P2) as the standby cost. In addition, since the route search unit 2B of the computer 2 searches for the relay route by including the set standby cost in the link cost, it is possible to search for a relay route with as little waiting time as possible before starting charging.
For this reason, by providing the occupant with the searched relay route on the display 7, it is possible to guide the occupant in advance on a relay route with little or no waiting time until charging starts.

Further, according to the route search device 1 of the first embodiment, the cost setting unit 2A sets the statistical value of the past start waiting time at the charging point as the standby cost, so that, as in the second embodiment described later, It is possible to set a relatively accurate cost without collecting information on the current reservation status of the charging point, which is necessary for obtaining the estimated waiting time at the time of arrival.
Therefore, there is an advantage that the route search device 1 that searches for a relay route in consideration of the standby cost at the charging point can be realized simply and inexpensively.

The “standby cost” used in the search for the relay route includes “charging time” necessary for charging performed at the charging point in addition to “start waiting time” until charging of the electric vehicle 20 is started. You may decide.
This “charging time” varies depending on the remaining battery amount at the start of charging and whether or not to perform full charging. For example, if the charging time for one charge is fixed as a preset value, By adding the set value to the start waiting time, a waiting cost corresponding to the waiting time until the end of charging at the charging point can be set.

[Second Embodiment]
FIG. 7 is a block diagram showing the overall configuration of the route search apparatus 1 according to the second embodiment. FIG. 8 is a diagram illustrating an example of a reference table 22 </ b> B related to a charging point reservation status, which is used by the route search apparatus 1 of the second embodiment.
In the route search device 1 of the present embodiment, the center computer 25 does not use the statistical value of the past start waiting time of each charging point, but the reference table 22B regarding the current reservation status as shown in FIG. It is assumed to be generated.

That is, the center computer 25 acquires the reservation information about whether the charging point is clogged with the reservation or is available from the server computer installed at the point every predetermined time (for example, 5 minutes). Based on the reservation information, the time table that can be used after the current time and the time zone that cannot be used are tabled for each charging point, and the reference table 22B in FIG. 8 is updated.
The center computer 25 distributes the downlink information including the updated reference table 22B to each vehicle 20, and the in-vehicle computer 2 of the vehicle 20 that has received the downlink information stores the reference table in the storage device 6 of the own vehicle. 22B is stored.

In the lookup table 22B illustrated in FIG. 8, the hatched portion indicates a time zone that is not available due to use or reservation, and the blank portion indicates another available time zone.
Therefore, for example, at the charging point with the station number “1”, the time zone from 13:00 to 13:00 is unusable and the time zone after 13:00 is usable. Further, at the charging point with the station number “2”, the time zone from 13: 0 to 14:30 is unusable, and the other time zone is a usable time zone.

In the route search device 1 of the present embodiment, in the standby cost setting (step ST8) shown in FIG. The predicted waiting time at the relay points P1 and P2 is calculated from the predicted time, and this waiting time is adopted as the waiting cost of the link cost of the equation (1).
For example, assuming that the estimated arrival time at the charging point (relay point) P1 with the station number “1” is 12:30, the cost setting unit 2A calculates the estimated waiting time of 30 minutes at the relay point P1. Set to the waiting cost corresponding to the start waiting time.

Also, assuming that the estimated arrival time at the charging point (relay point) P2 with the station number “2” is 13:00, the cost setting unit 2A calculates 90 minutes, which is the predicted waiting time at the relay point P1. Set to the waiting cost corresponding to the start waiting time.
As described above, in the route search device 1 according to the second embodiment, the charging point P1 is set as the standby cost corresponding to the start waiting time until the cost setting unit 2A starts charging the electric vehicle 20 at the charging points P1 and P2. , P2 is used to estimate the waiting time when the vehicle arrives, which is estimated from the current reservation status.

Note that the route search unit 2B of the in-vehicle computer 2 searches for a relay route that minimizes the link cost of the equation (1) using the standby cost set by the cost setting unit 2A as described above. Is the same as in the first embodiment. Also in the second embodiment, the charging time may be included in the standby cost.
According to the route search device 1 of the second embodiment, the route search unit 2B includes the standby cost set based on the estimated waiting time at the time of arrival of the host vehicle estimated from the current reservation status in the link cost. Therefore, it is possible to more accurately search for a relay route including a charging point with a surely low waiting time upon arrival.

[Reservation notification section]
By the way, in the route search apparatus 1 of 2nd Embodiment, since the vehicle 20 grasps | ascertains the reference table 22B of FIG. 8 which shows the present reservation situation of a charging point, when a charging point is empty, it reserves automatically. The in-vehicle computer 2 is provided with a reservation notifying unit 2C (see FIG. 7).
That is, the reservation notifying unit 2C executes a process of making a reservation at the charging point through the wireless communication device 10 when the charging point is empty at the estimated arrival time of the charging point via the searched relay route.

However, if the vehicle 20 automatically makes a reservation at the charging point as described above, for example, if the reserved vehicle 20 arrives earlier than the estimated arrival time, the waiting time is longer than expected. On the other hand, if it arrives later than the estimated arrival time, it will inconvenience the charging point operator.
Therefore, if it is found that the reservation does not arrive at the estimated arrival time after making a reservation at the charging point, it is preferable that the reservation notifying unit 2C perform a process for changing the reservation for the charging point.

If this process is performed, for example, if it is found that the vehicle arrives earlier than the expected arrival time, the reservation time for using the charging point is advanced, or conversely, the own vehicle is earlier than the estimated arrival time. If it is found that the vehicle arrives late, the charging facility at the charging point can be used efficiently by delaying the reservation time or canceling the reservation.
As described above, the reservation change performed by the reservation notification unit 2C may include not only a change in the reservation time but also a cancellation of the reservation.

In addition, when it is determined that the vehicle does not arrive at the estimated arrival time after making a reservation at the charging point, a process for re-executing the cost setting by the cost setting unit 2A and the search process by the route searching unit 2B is performed. You may make it notify to 2C of notification parts.
In this case, the cost setting unit 2A sets the estimated waiting time upon arrival of the host vehicle estimated from the latest reservation status (FIG. 8) as the standby cost, and the route search unit 2B sets the standby cost as the link cost. Therefore, it is possible to provide the passenger with a relay route that takes into account the latest reservation status.

[Another example of calculating the estimated waiting time]
In the second embodiment, the “predictive waiting time” at the predicted arrival time takes into consideration not only one time zone in which the charging point is unavailable, but also the length of the free time between the unavailable time zones. It is preferable to calculate by
For example, as shown in FIG. 8, at the charging point with the station number “3”, reservations are already made in the time zone from 12:00 to 13:00 and the time zone from 13:15 to 14:00. It shall be.

Further, it is assumed that the predicted arrival time of the vehicle at the charging point is 12:30, and the charging time of the vehicle 20 needs to be at least 60 minutes.
In this case, assuming that the predicted waiting time is uniformly from the estimated arrival time (12:30) to the next available time (13:00), the waiting cost is set to “30 minutes” and then 13: 0 to 13: The charging is performed for 15 minutes up to 15, but in this case, charging can be performed only in a very short time which is shorter than the charging time (60 minutes) required for the vehicle 20.

Therefore, when the free time between one unavailable time zone and the next unavailable time zone is less than the charging time (60 minutes), these time zones are regarded as a series of time zones. It is preferable to calculate a predicted waiting time.
That is, in the case of the station number “3” in FIG. 8, “90” until the next available time (14:00), not the available time (13:00) immediately after the predicted arrival time (12:30). Minutes "is the estimated waiting time.

  As described above, it is assumed that there is no free time less than the charge time required for charging the vehicle, and the estimated waiting time is calculated, so that charging in an extremely short time less than the required charge time is forced. Can be avoided in advance, and the predicted waiting time required for the vehicle can be accurately calculated.

For example, in the charging point with the station number “2” shown in FIG. 8, if the predicted arrival time of the host vehicle is 12:45, a reservation after 13:00 is made even if it is empty at that time. Since it is already in, it can only be charged for 15 minutes less than the charging time.
Therefore, even if the charging point is an empty time zone at the estimated arrival time of the host vehicle, it is not only that the charging point is uniformly empty and the start waiting time is not zero, When the time until the reservation start time is a short time less than the charging time, it is preferable to calculate the predicted waiting time by assuming that the charging point is not vacant.

  When the station number in FIG. 8 is “2”, the end time of the next reservation after the predicted arrival time (12:45) is 14:30, so 105 minutes from 12:45 to 14:30 It is set as the predicted waiting time.

[Third Embodiment]
FIG. 9 is a diagram illustrating an example of a reference table 22 </ b> C regarding the fullness of charging points. In this reference table 22C, “◯” means that the charging point of the station number is vacant, and “X” indicates that the charging point of the station number is full and cannot be used.

In this case, the cost setting unit 2A sets the standby cost for the charging point “◯” to be relatively small and sets the standby cost to a relatively large value for the charging point “x”. A standby cost corresponding to the waiting time until charging of the automobile 20 can be set.
However, adopting the current full availability situation as shown in FIG. 9 has the advantage of simplifying the standby cost setting process, but if it takes a relatively long time for the vehicle to arrive at the charging point, There is a possibility that a free charging point is not available at the time of arrival of the vehicle.

  Therefore, from the viewpoint of minimizing the waiting time when arriving at the relay point, it is preferable to set an accurate predicted waiting time based on the current reservation status (FIG. 8) as the waiting cost as in the second embodiment. .

[Other variations]
Each above-mentioned embodiment is illustration and is not restrictive. The scope of the present invention is defined by the terms of the claims, and all modifications within the scope equivalent to the structures described therein are included in the scope of the present invention.
For example, in the above-described embodiment, the in-vehicle computer 2 of the electric vehicle 20 performs the route search of the present invention, but the route computer of the present invention performs the route search of the present invention, and the result is obtained as the electric vehicle 20. May be notified.

DESCRIPTION OF SYMBOLS 1 Route search apparatus 2 In-vehicle computer 2A Cost setting part 2B Route search part 2C Reservation notification part 7 Display

Claims (8)

A route search device for searching a relay route to a destination via a relay point with a charging point,
A cost setting unit for setting a standby cost corresponding to the waiting time at the charging point;
And a route search unit that searches for the relay route by including the set standby cost in a link cost.   The route search device according to claim 1, wherein the cost setting unit sets the standby cost based on a statistical value of a past waiting time at the charging point.   The route search device according to claim 1, wherein the cost setting unit sets the standby cost based on a current full availability condition at the charging point.   The route search device according to claim 1, wherein the cost setting unit sets the standby cost based on a predicted waiting time at the time of arrival of the host vehicle estimated from a current reservation state of the charging point.   5. The route search device according to claim 4, further comprising a reservation notifying unit configured to make a reservation at the charging point when the charging point is empty at the estimated arrival time of the charging point via the searched relay route. . The reservation notification unit performs at least one of the following (a) and (b) when the vehicle does not arrive at the estimated arrival time after making a reservation at the charging point. The route search device described in 1.
(A) 1st process which performs again the cost setting by a cost setting part, and the search process by a route search part (b) 2nd process which changes the reservation with respect to a charging point A route search method for searching a relay route to a destination via a relay point with a charging point,
Setting a standby cost corresponding to a waiting time at the charging point;
And searching for the relay route by including the set standby cost in the link cost.   A computer program for causing a computer to execute each step of the route search method according to claim 7.

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