Power transmission device, non-contact power transmission system, and control method for power transmission device

Abstract

To provide a power transmission device, a non-contact power transmission system, and a power transmission device controlling method by which a vehicle can properly travel on the power transmission device.SOLUTION: In a non-contact power charging system 100, a power feeding system 2 capable of transmitting power to a vehicle 1 in a non-contact manner, includes a power conversion device 21, a sensor unit 22, a power feeding mat 23, a plurality of power transmission coils 231, and a controller 24. The plurality of power transmission coils 231 are configured to transmit power to a power reception coil installed in the vehicle 1 in a non-contact manner, and are arranged in a prescribed direction on a road. A display layer is disposed on the plurality of power transmission coils 231. The controller 24 controls a display form of the display layer so as to guide the vehicle 1 in accordance with the traveling state of the vehicle 1.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a power transmission device, a non-contact power transmission system, and a technique for non-contact power transmission to a power receiving coil mounted on a vehicle.

Background Art

[0002] The vehicle disclosed in Japanese Patent Application Laid-Open No. 2020-10451 (Patent Document 1) includes a power receiving device. The power receiving device is mounted on the lower part of the vehicle and is configured to enable non-contact power reception (wireless charging) with a power transmission device buried in the road surface.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a non-contact power transmission system, power can be transmitted even while the vehicle is running. In order to achieve effective power transmission, it is desirable that the vehicle runs appropriately on the power transmission device. However, depending on the driver (for example, a driver with low driving skills), the environment (for example, at a dim time), etc., there is a possibility that the vehicle cannot run appropriately on the power transmission device.

[0005] The present disclosure has been made to solve the above problems, and one of the objects of the present disclosure is to enable a vehicle to run appropriately on a power transmission device.

Means for Solving the Problems

[0006] (1) A power transmission device according to an aspect of the present disclosure includes a plurality of power transmission coils, a display unit, and a control unit. The power transmission coils are configured to transmit power to a power reception coil mounted on a vehicle in a non-contact manner and are arranged on a road in a predetermined direction. The display unit is provided on the plurality of power transmission coils. The control unit controls the display unit. The control unit controls the display mode of the display unit so as to guide the vehicle according to the traveling state of the vehicle.

[0007] (2) When the traveling speed of the vehicle is lower than the specified speed of the road, the control unit controls the display unit to emit light in a light emission pattern flowing in the traveling direction of the road where the power transmission coil is installed. (3) The slower the traveling speed of the vehicle is, the faster the speed at which the light emission pattern flows.

[0008] In the configuration of (1) above, the vehicle is guided according to the traveling state of the vehicle by the display mode of the display unit. For example, in the configurations of (2) and (3) above, when the traveling speed of the vehicle is lower than the specified speed of the road, the display unit emits light in a light emission pattern flowing in the traveling direction of the road. As a result, acceleration of the vehicle can be promoted and the vehicle can travel at an appropriate speed. As a result, traffic congestion can be suppressed.

[0009] (4) When the vehicle is traveling with the power reception coil shifted to the right with respect to the plurality of power transmission coils, the control unit controls the display unit to display an icon or a message for causing the vehicle to move closer to the left, while when the vehicle is traveling with the power reception coil shifted to the left with respect to the plurality of power transmission coils, the control unit controls the display unit to display an icon or a message for causing the vehicle to move closer to the right.

[0010] (5) When the traveling position of the vehicle is maintained on the plurality of power transmission coils, the control unit controls the display unit to emit light in a first emission color, while when the traveling position of the vehicle is outside the plurality of power transmission coils, the control unit controls the display unit to emit light in a second emission color different from the first emission color.

[0011] When the power receiving coil is misaligned with respect to a plurality of power transmitting coils, the power transmission efficiency from the power transmitting device to the vehicle may decrease. In the configurations (4) and (5) above, misalignment of the power receiving coil with respect to the plurality of power transmitting coils can be suppressed. As a result, the power transmission efficiency can be improved.

[0012] (6) A non-contact power transmission system according to another aspect of the present disclosure includes the above-described power transmission device and a vehicle. (7) The vehicle includes a display device that provides information to a driver of the vehicle and a control device that controls the display device. The control device controls the display device to display a notification for adjusting the traveling position of the vehicle. (8) The notification includes an icon for improving the power transmission efficiency from a plurality of power transmitting coils to the power receiving coil. (9) The display device includes a head-up display. The control device controls the head-up display to display a notification when the vehicle approaches within a predetermined distance from the power transmission device.

[0013] According to the configurations (6) to (9) above, a notification for adjusting the traveling position of the vehicle can also be given by a display device such as a head-up display mounted on the vehicle, and the vehicle can be guided.

[0014] (10) In a method for controlling a power transmission device according to still another aspect of the present disclosure, the power transmission device includes a plurality of power transmitting coils configured to transmit power to a power receiving coil mounted on a vehicle in a non-contact manner. The method for controlling the power transmission device includes a step of detecting a traveling state of the vehicle and a step of guiding the vehicle by changing a display mode of a display unit provided on the plurality of power transmitting coils according to the traveling state of the vehicle.

[0015] According to the method (10) above, similar to the configuration (1), the vehicle can travel appropriately on the power transmission device.

Advantages of the Invention

[0016] According to the present disclosure, the vehicle can travel appropriately on the power transmission device.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Embodiments for Carrying Out the Invention

[0018] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and the description thereof will not be repeated.

[0019] [Embodiment 1] <Overall System Configuration> FIG. 1 is a perspective view schematically showing the overall configuration of a contactless charging system according to an embodiment of the present disclosure. The contactless charging system 100 includes a vehicle 1 and a power supply system 2.

[0020] Vehicle 1 is configured to receive power supply (power feeding) from the outside and charge an in-vehicle battery 11 (see FIG. 3) with the power. Vehicle 1 is, for example, a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), or a battery electric vehicle (BEV).

[0021] The power feeding system 2 is configured to transmit power to Vehicle 1 in a non-contact manner. The power feeding system 2 includes a power conversion device 21, a sensor unit 22, a power feeding mat 23, and a controller 24. The power feeding system 2 corresponds to the "power transmission device" according to the present disclosure.

[0022] The power conversion device 21 supplies power to the power feeding mat 23 according to the control by the controller 24. The power conversion device 21 is connected to an external AC power source (for example, a commercial power source) 900. The power conversion device 21 converts the voltage of the AC power supplied from the AC power source 900 to an appropriate value and supplies the AC power after the voltage conversion to the power feeding mat 23. Although FIG. 1 shows an example in which the power conversion device 21 is exposed on the ground, the power conversion device 21 may be buried underground.

[0023] The sensor unit 22 detects the position of Vehicle 1 passing over the power feeding mat 23 and outputs a signal indicating the detection result to the controller 24. The sensor unit 22 is, for example, an optical sensor and includes at least one of a camera, a radar, and a LIDAR (Laser Imaging Detection and Ranging). However, the detection method of Vehicle 1 by the sensor unit 22 is not particularly limited. The sensor unit 22 may be, for example, a weight sensor that detects the weight of Vehicle 1.

[0024] The power supply mat 23 is configured to be able to transmit power to the vehicle 1 in a non-contact manner. The power supply mat 23 has a mat shape and is installed on the road surface (on the road). The power supply mat 23 may be configured to be movable (portable), and may have flexibility or flexibility that can be wound in a roll shape. Instead of the movable power supply mat 23, it is also possible to adopt a device fixed to the road surface. The configuration of the power supply mat 23 will be described with reference to FIG. 2.

[0025] The controller 24 identifies the traveling position and traveling speed of the vehicle 1 based on the signal from the sensor unit 22. The controller 24 controls the power conversion device 21 and the power supply mat 23 so as to supply AC power to the vehicle 1.

[0026] Note that the controller 24 is configured to be able to communicate with the vehicle 1. The controller 24 may acquire the traveling position and traveling speed of the vehicle 1 from the vehicle 1 by communication with the vehicle 1. In the example shown in FIG. 1, the controller 24 is arranged in the same housing as the power conversion device 21, but the controller 24 may be arranged separately from the power conversion device 21. Further, the controller 24 may be arranged in an external server and control the power conversion device 21 by wireless communication. The controller 24 corresponds to the "control unit" according to the present disclosure.

[0027] FIG. 2 is a diagram for explaining the state of power transmission from the power supply mat 23 to the vehicle 1. The power supply mat 23 includes a plurality of power transmission coils 231 and a display layer 232.

[0028] The plurality of power transmission coils 231 are arranged in a line on the road surface. Each of the plurality of power transmission coils 231 may be formed in a square shape in plan view as shown in FIG. 1, or may be formed in a hexagonal shape in plan view. Alternatively, each power transmission coil 231 may be formed in a shape different from a square shape and a hexagonal shape (for example, a solenoid shape) in plan view.

[0029] When the vehicle 1 is detected above a certain power transmission coil 231 among the plurality of power transmission coils 231, the controller 24 supplies AC power to the power transmission coil 231. Then, an alternating current flows through the power transmission coil 231, forming an electromagnetic field around the power transmission coil 231. The power receiving coil 161 in the power receiving device mounted on the vehicle 1 receives power non - contact through the electromagnetic field. After that, when the vehicle 1 is no longer detected above the power transmission coil 231, the controller 24 stops supplying AC power to the power transmission coil 231. By performing such a series of controls for each of the power transmission coils 231 arranged in a row, power can be transmitted to the running vehicle 1 non - contact. As a result, the battery 11 mounted on the vehicle 1 can be charged.

[0030] The display layer 232 is provided above (on the upper surface) of the power transmission coil 231. The display layer 232 includes light - emitting elements such as LEDs (Light Emitting Diodes). The display layer 232 may include a display such as a liquid crystal display. The display layer 232 displays a predetermined image (icon or message) in a manner visible to the driver of the vehicle 1 according to the control by the controller 24. More specifically, the display layer 232 displays an image for guiding the vehicle 1. This process is referred to as "vehicle guidance process" and will be described in detail later. The display layer 232 corresponds to the "display unit" according to the present disclosure.

[0031] <Vehicle Configuration> FIG. 3 is a block diagram showing a typical hardware configuration of the vehicle 1. In this example, the vehicle 1 is an electric vehicle. The vehicle 1 includes a battery 11, a system main relay (SMR) 12, a drive device 13, a power converter 14, charging relays 151, 152, a power receiving device 16, an inlet 17, a communication module 181, a GPS (Global Pointing System) receiver 182, a resolver 183, a camera 184, a HMI (Human Machine Interface) 19, and an ECU 10.

[0032] The battery 11 supplies power to the drive device 13 for generating the driving force of the vehicle 1. Further, the battery 11 stores the charging power supplied from the outside and also stores the regenerative power generated by the drive device 13. The battery 11 is a battery pack including a plurality of cells (not shown). Each cell is a secondary battery such as a lithium-ion battery or a nickel-metal hydride battery.

[0033] A monitoring unit 110 is provided in the battery 11. Although not shown, the monitoring unit 110 includes a voltage sensor, a current sensor, and a temperature sensor. The voltage sensor detects the voltage of the battery 11. The current sensor detects the current input to and output from the battery 11. The temperature sensor detects the temperature of the battery 11. Each sensor outputs its detection result to the ECU 10.

[0034] The SMR 12 is electrically connected between the battery 11 and the drive device 13. The SMR 12 is closed / opened in response to a control command from the ECU 10.

[0035] The drive device 13 is electrically connected to the SMR 12. The drive device 13 includes a converter 131, an inverter 132, and a motor generator 133.

[0036] The converter 131 boosts the DC power of the battery 11. The inverter 132 converts the DC power boosted by the converter 131 into AC power and outputs it to the motor generator 133. The motor generator 133 is driven using the power from the battery 11. The driving force of the motor generator 133 is transmitted to the drive wheels. On the other hand, during braking of the vehicle 1, when reducing acceleration on a downhill slope, etc., the motor generator 133 performs regenerative power generation. The power generated by the motor generator 133 is supplied to the battery 11 via the inverter 132 and the converter 131.

[0037] The power converter 14 is, for example, an AC / DC converter. The power converter 14 converts the AC power supplied from the charging facility via the charging cable into DC power for charging the battery 11. Also, the power converter 14 converts the AC power supplied from the power feeding mat 23 via the power receiving device into DC power for charging the battery 11.

[0038] The charging relay 151 is electrically connected between the power receiving device 16 and the power converter 14. The charging relay 151 is closed / open in response to a control command from the ECU 10. When the charging relay 151 is closed and the SMR 12 is closed, power transmission between the power receiving device 16 and the battery 11 becomes possible.

[0039] The charging relay 152 is electrically connected between the inlet 17 and the power converter 14. The charging relay 152 is closed / open in response to a control command from the ECU 10. When the charging relay 152 is closed and the SMR 12 is closed, power transmission between the inlet 17 and the battery 11 becomes possible.

[0040] The power receiving device 16 is disposed, for example, on the lower surface of the floor panel forming the bottom surface of the vehicle 1 (see FIG. 2). The power receiving device 16 includes a power receiving coil 161. The power receiving coil 161 receives power transmitted from the power transmission coil 231 in the power feeding mat 23 in a non-contact manner.

[0041] The inlet 17 is configured such that a charging connector 800 of a charging facility (not shown) is electrically connected during plug-in charging.

[0042] The communication module 181 is a DCM (Digital Communication Module) configured to enable two-way communication with the power feeding system 2. The GPS receiver 182 identifies the current position of the vehicle 1 based on radio waves transmitted from a satellite (not shown). The resolver 183 detects the traveling speed (vehicle speed) of the vehicle 1. The camera 184 captures an image in front of the vehicle 1.

[0043] The HMI 19 receives user operations. Also, the HMI 19 presents various information to the user. The HMI 19 corresponds to the "display device" according to the present disclosure.

[0044] The ECU 10 includes a processor 101, a memory 102, and an input / output port (not shown). The ECU 10 controls devices so that the vehicle 1 reaches a desired state according to signals from each sensor and the like. The ECU 10 may be configured by being divided into a plurality of ECUs for each function. The ECU 10 corresponds to the "control device" according to the present disclosure.

[0045] FIG. 4 is a diagram showing a configuration example of the HMI 19. The HMI 19 includes an instrument panel (hereinafter referred to as "instrument panel") 191, a HUD (Head-Up Display) 192, and a navigation screen 193.

[0046] The instrument panel 191 is an instrument panel on which meters are installed, and displays various states of the vehicle 1 according to a control signal from the ECU 10. Specifically, the instrument panel 191 displays a speedometer, a trip meter, the SOC of the battery 11, warning lights, and the like. Note that a multi-information display (MID) may also be adopted instead of the instrument panel 191.

[0047] The HUD 192 projects various information as virtual images in front of the driver's field of view. Specifically, the HUD 192 displays the vehicle speed of the vehicle 1, the traveling direction to the destination, traffic signs, and the like.

[0048] The navigation screen 193 is a display of a navigation system (not shown). The navigation system displays the current location of the vehicle 1 and a recommended route to the destination of the vehicle 1 on the navigation screen 193 based on the GPS data of the vehicle 1 and the road map data.

[0049] An example in which various types of information regarding the power supply mat 23 are displayed on the HUD 192 will be described below. However, these pieces of information may be displayed on the instrument panel 191 instead of or in addition to the HUD 192, or may be displayed on the navigation screen 193.

[0050] <Vehicle guidance process> FIG. 5 is a diagram for explaining the display mode of the display layer 232 of the power supply mat 23 in the first embodiment. The display layer 232 emits light in a light emission pattern that flows in the traveling direction of the road (the traveling direction of the vehicle 1). In the light emission pattern of the example shown in FIG. 5, arrows emit light sequentially (sequentially) along the traveling direction of the road (the direction from the front to the back in the figure), so that it appears to the human eye that the arrows are flowing.

[0051] At night, during rainfall, inside a tunnel, etc., the visibility of the power supply mat may decrease depending on the environment. Then, when the display layer 232 is not provided, it may become difficult for the driver of the vehicle 1 to recognize whether the vehicle 1 is traveling properly on the power supply mat. By the display layer 232 emitting light along the traveling direction of the road, the driver can easily recognize the route on the power supply mat 23 along which the vehicle 1 should travel.

[0052] In addition, when the amount of electric power stored in the battery 11 is relatively small, etc., in order to receive power from the power supply mat 23 for as long as possible, it is conceivable that the vehicle 1 reduces its traveling speed on the power supply mat 23. Then, the following vehicle also has to reduce its traveling speed, and as a result, there is a possibility of causing traffic congestion. When the traveling speed of the vehicle 1 is slower than the specified speed of the road (for example, the speed limit), by setting the speed at which the light emission pattern of the display layer 232 flows (hereinafter, also referred to as the "flow speed") to an appropriate speed, the acceleration of the vehicle 1 can be promoted. Note that the promotion of acceleration may include the suppression of deceleration.

[0053] The flow rate of the light emission pattern can be set according to the traveling speed of Vehicle 1. More specifically, if the flow rate is too slow, the effect of accelerating the vehicle 1 is weak. Conversely, if the flow rate is too fast, the acceleration of the vehicle 1 can be excessively promoted. The flow rate of the light emission pattern is preferably faster than the vehicle speed and slower than the regulated speed of the road. For example, when the regulated speed is 60 km / h and the vehicle speed is 40 km / h, the flow rate can be set to 50 km / h. Thereby, an appropriate effect of accelerating promotion can be obtained.

[0054] Furthermore, it is more preferable that the flow rate of the light emission pattern is increased as the vehicle speed is slower (as the speed difference between the regulated speed and the vehicle speed is larger). For example, when the regulated speed of the road is 60 km / h and the vehicle speed is 30 km / h, the flow rate can be increased compared to the case where the vehicle speed is 40 km / h. Thereby, the effect of accelerating promotion can be enhanced.

[0055] <Processing Flow> FIG. 6 is a flowchart showing the processing procedure of the vehicle guidance process in Embodiment 1. This flowchart is executed, for example, when a predetermined condition is satisfied (at night, during rainfall, etc.). In the figure, the processing executed by Vehicle 1 (ECU10) is shown on the left side, and the processing executed by the power supply system 2 (Controller 24) is shown on the right side. Each step is realized by software processing by ECU10 or Controller 24, but may also be realized by hardware (electric circuit) arranged in ECU10 or Controller 24. Hereinafter, the steps are abbreviated as S. The same applies to other flowcharts (see FIG. 8) described later.

[0056] In S21, the controller 24 controls the display layer 232 of the power supply mat 23 so that all the arrows emit light (that is, so that all the arrows remain lit). The controller 24 of the power supply system 2 continues the light emission (either full lighting / a predetermined light emission pattern) of the display layer 232 while the above-mentioned predetermined condition is satisfied.

[0057] In S11, the ECU 10 determines whether the vehicle 1 has approached the power supply mat 23. For example, the ECU 10 can determine whether it has approached within a predetermined distance (for example, several tens of meters) from the power supply mat 23 through communication with the power supply mat 23 via the communication module 181. When the position information of the power supply mat 23 is included in the map information, the ECU 10 may determine whether it has approached the power supply mat 23 based on the position information of the vehicle 1 by the GPS receiver 182. The ECU 10 may also determine whether it has approached the power supply mat 23 based on the image captured by the camera 184.

[0058] When the vehicle 1 has approached the power supply mat 23 (YES in S11), the ECU 10 controls the HUD 192 to display information regarding power supply from the power supply mat 23 (S12). This display is preferably realized by a pop-up display. Specifically, the ECU 10 can control the HUD 192 to notify the approach to the power supply mat 23 or guide the power supply mat 23. In addition, the ECU 10 can cause the HUD 192 to display a meter for displaying the charging power and charging efficiency (described later in S14) to the vehicle 1.

[0059] For example, when the SOC of the battery 11 is lower than a predetermined value, the ECU 10 controls the communication module 181 to transmit a power supply request from the power supply mat 23 to the vehicle 1. The power supply request includes a requested power supply power (a requested value of the power supply power from the power supply mat 23 to the vehicle 1).

[0060] When receiving a power supply request from the vehicle 1 (YES in S22), the controller 24 acquires the traveling speed (vehicle speed) of the vehicle 1 (S23). The controller 24 can calculate the vehicle speed based on the detection result by the sensor unit 22 (for example, a camera, a radar, or a lidar). The controller 24 may also acquire the vehicle speed obtained by the resolver 183 from the vehicle 1.

[0061] In S24, the controller 24 controls the display layer 232 of the power supply mat 23 so that the arrows emit light in a chain along the traveling direction of the road. At this time, the controller 24 controls the flow rate of the light emission pattern of the power supply mat 23 according to the vehicle speed. As described with reference to FIG. 5, the controller 24 can adjust the flow rate of the light emission pattern to be faster than the vehicle speed and slower than the specified speed of the road (for example, the value set at the time of installation of the power supply mat 23). Further, the slower the vehicle speed, the faster the controller 24 can set the flow rate of the light emission pattern.

[0062] While the vehicle 1 is traveling on the power supply mat 23, the controller 24 controls the power conversion device 21 so that power is supplied from the power supply mat 23 to the vehicle 1 according to the required power supply power from the vehicle 1 (S25).

[0063] In S14, the ECU 10 causes the meter on the HUD 192 to display the power supply power from the power supply mat 23 (the received power of the power receiving coil 161) and the power transmission efficiency. The ECU 10 can use, for example, the ratio of the received power of the power receiving coil 161 to the required power supply power (= received power / required power supply power) as the power transmission efficiency. The power transmission efficiency may be displayed as a gauge on the HUD 192. The higher the power transmission efficiency, the longer the displayed gauge becomes.

[0064] In S15, the ECU 10 determines whether the vehicle 1 has left the power supply mat 23. If the vehicle 1 has not left the power supply mat 23 (NO in S15), that is, if the vehicle 1 is traveling on the power supply mat 23, the ECU 10 returns the process to S13. Thereby, the power supply from the power supply mat 23 to the vehicle 1 is continued. During that time, the flow rate of the light emission pattern of the power supply mat 23 is adjusted according to the vehicle speed.

[0065] On the other hand, when the vehicle 1 detaches from the power feeding mat 23 (YES in S15), that is, when the vehicle 1 is no longer traveling on the power feeding mat 23, the ECU 10 advances the process to S16. Then, the pop-up display of the information regarding the power feeding from the power feeding mat 23 ends (S16). Also, since the controller 24 no longer receives the power feeding request from the vehicle 1 (NO in S22), the power feeding from the power feeding mat 23 to the vehicle 1 stops (S26).

[0066] As described above, in the first embodiment, according to the traveling state of the vehicle 1, the display mode of the display layer 232 of the power feeding mat 23 is controlled so as to guide the vehicle 1. More specifically, when the vehicle speed (an example of the traveling state) is lower than the specified speed of the road, the flow rate of the light emission pattern of the display layer 232 is controlled according to the vehicle speed so as to promote the acceleration of the vehicle 1. Thereby, the vehicle 1 can travel on the power feeding mat 23 at an appropriate vehicle speed.

[0067] [Second Embodiment] In the first embodiment, the configuration for promoting the acceleration of the vehicle 1 by the light emission pattern of the display layer 232 of the power feeding mat 23 has been described. In the second embodiment, a configuration for suppressing the lateral displacement (the direction perpendicular to the traveling direction of the road) of the vehicle 1 with respect to the power feeding mat 23 by the display of the display layer 232 will be described. The configurations of the vehicle and the power feeding system in the second embodiment are equivalent to the configurations of the vehicle 1 and the power feeding system 2 in the first embodiment (see FIGS. 1 to 4).

[0068] FIG. 7 is a diagram for explaining the display mode of the display layer 232 of the power supply mat 23 in Embodiment 2. As shown in FIG. 7(A), when the vehicle 1 is running while being displaced to the left side of the center of the power supply mat 23, since the power receiving coil 161 is displaced to the left side of the center of the power supply mat 23 (the position of the power transmission coil 231), compared with the case where the power receiving coil 161 is positioned directly above the center of the power supply mat 23 (the power transmission coil 231), the power transmission efficiency from the power transmission coil 231 to the power receiving coil 161 may decrease. Therefore, in Embodiment 2, an icon (which may be an animation) or a message (character information) for shifting the vehicle 1 to the right is displayed on the display layer 232 of the power supply mat 23. For example, an icon of a rightward arrow is displayed on the display layer 232. Instead of or in addition to the icon, a message "Shift to the right" may be displayed on the display layer 232.

[0069] Conversely, when the vehicle 1 is running while being displaced to the right side of the center of the power supply mat 23 (see FIG. 7(B)), an icon or a message for shifting the vehicle 1 to the left is displayed on the display layer 232 of the power supply mat 23. For example, an icon of a leftward arrow may be displayed on the display layer 232, or a message "Shift to the left" may be displayed on the display layer 232.

[0070] The display mode in Embodiment 1 and the display mode in Embodiment 2 can also be combined. Specifically, both an arrow for promoting acceleration and an arrow for shifting to the right or left can be displayed on the display layer 232 of the power supply mat 23. Also, both an arrow for promoting acceleration and a message "Shift to the right" or "Shift to the left" can be displayed. They may be displayed simultaneously, or may be displayed one by one in a predetermined order (for example, alternately).

[0071] FIG. 8 is a flowchart showing the processing procedure of the vehicle guidance process in Embodiment 2. This flowchart is different from the flowchart in Embodiment 1 (see FIG. 6) in that it includes the processes of S43 and S44 instead of the processes of S23 and S24. The other processes are the same as the corresponding processes in the flowchart of Embodiment 1.

[0072] When the power supply request is received from vehicle 1 (YES in S42), the controller 24 acquires the positional deviation (positional deviation amount and positional deviation direction) of vehicle 1 with respect to the power supply mat 23 (S43). The controller 24 extracts, for example, the contour of the power supply mat 23 and the contour of vehicle 1 by known image recognition processing. The controller 24 can calculate the positional deviation of vehicle 1 based on the relative positional relationship between the two (for example, the distance between the contour of the power supply mat 23 and the contour of vehicle 1 in the lateral direction of vehicle 1).

[0073] When the positional deviation amount of vehicle 1 is greater than the specified amount, the controller 24 controls the display layer 232 to display an icon or a message for reducing the positional deviation amount of vehicle 1 according to the positional deviation direction of vehicle 1 (S44). Since this process has been described in detail in FIGS. 7(A) and 7(B), the description will not be repeated. When the positional deviation amount of vehicle 1 is less than or equal to the specified amount, the controller 24 can make the above icon or message non-displayed.

[0074] In addition to the display on the display layer 232 of the power supply mat 23, it is preferable to also display a display for reducing the positional deviation amount of vehicle 1 on the HUD 192 of vehicle 1 (S32). The ECU 10 can display, for example, a simple accelerometer (G meter) on the HUD 192.

[0075] FIG. 9 is a diagram showing an example of the G meter displayed on the HUD 192. The change in the acceleration (G) of vehicle 1 is shown by a display in which a ball placed at the center of concentric circles rolls. As an example, when vehicle 1 is moved to the right, an animation of rolling the ball in the right direction can be displayed on the G meter. Thereby, the driver can intuitively understand that it is better to move vehicle 1 to the right.

[0076] As described above, also in the second embodiment, the display mode of the display layer 232 of the power supply mat 23 is controlled so as to guide the vehicle 1 according to the running state of the vehicle 1. More specifically, icons or messages on the display layer 232 are controlled so as to adjust the lateral position of the vehicle 1 according to the amount of positional deviation and the direction of positional deviation (an example of the running state) of the vehicle 1. As a result, the vehicle 1 can travel at an appropriate lateral position on the power supply mat 23. As a result, the power transmission efficiency from the power supply mat 23 to the power receiving device 16 can be improved.

[0077] [Embodiment 3] In the third embodiment, a configuration for setting the emission color of the display layer 232 of the power supply mat 23 according to the positional deviation of the vehicle 1 with respect to the power supply mat 23 will be described. The configurations of the vehicle and the power supply system in the third embodiment are also equivalent to the configurations of the vehicle 1 and the power supply system 2 in the first embodiment (see FIGS. 1 to 4).

[0078] FIG. 10 is a diagram for explaining the display mode of the display layer 232 of the power supply mat 23 in the third embodiment. As shown in FIG. 10, the display layer 232 of the power supply mat 23 emits light at predetermined intervals. In this example, the display layer 232 emits light at each position of the power transmission coil 231. On the other hand, in the vehicle 1, the position of the power transmission coil 231 specified by the camera 184 detecting the emission of the display layer 232 is displayed on the HUD 192. In the third embodiment, the display color of the display layer 232 is changed between the case where the traveling position of the vehicle 1 is maintained on the power supply mat 23 and the case where the traveling position of the vehicle 1 deviates from the power supply mat 23.

[0079] In the example of FIG. 10(A), the vehicle 1 is traveling straight. When the vehicle 1 travels as it is without the driver changing the vehicle operation (such as a steering operation, an accelerator operation, a brake operation, etc.), the traveling position of the vehicle 1 is maintained on the power supply mat 23. In this case, for example, the display layer 232 emits white light at the position of the power transmission coil 231. On the HUD 192, the power transmission coil 231 is displayed in white.

[0080] In the example of Fig. 10(B), vehicle 1 is traveling while turning right. If vehicle 1 travels straight, the traveling position of vehicle 1 is maintained on the power supply mat 23 up to the two front power transmission coils 231, but the traveling position of vehicle 1 deviates from the power supply mat 23 at the third and subsequent power transmission coils 231 from the front. In such a case, in the section where the traveling position of vehicle 1 is maintained on the power supply mat 23, for example, the display layer 232 emits white light at the position of the power transmission coil 231. On the HUD 192, the power transmission coil 231 is displayed in white. On the other hand, in the section where the traveling position of vehicle 1 deviates from the power supply mat 23, for example, the display layer 232 emits red light at the position of the power transmission coil 231. On the HUD 192, the position of the power transmission coil 231 is displayed in white.

[0081] Although an example in which the display color on the HUD 192 is fixed to white has been described, as shown in Fig. 10(C), the display color on the HUD 192 may be changed in addition to the emission color of the display layer 232. In the section where the traveling position of vehicle 1 deviates from the power supply mat 23, for example, the display layer 232 may emit red light at the position of the power transmission coil 231, and the position of the power transmission coil 231 may be displayed in red on the HUD 192.

[0082] In this way, by changing the emission color of the display layer 232 of the power supply mat 23 according to the traveling position of vehicle 1, the driver can easily recognize that vehicle operation (mainly steering operation) is required to continue the state where the traveling position of vehicle 1 is on the power supply mat 23. Furthermore, by linking the display on the HUD 192 with the emission color of the display layer 232, it becomes possible for the driver to more easily recognize the necessity of vehicle operation.

[0083] Note that the controller 24 of the power supply system 2 may set a light emission pattern (for example, blinking period) according to the traveling position of vehicle 1 in addition to the emission color of the display layer 232. The controller 24 can, for example, keep the display layer 232 constantly lit in the section where the traveling position of vehicle 1 is maintained on the power supply mat 23, while blinking the display layer 232 in the section where the traveling position of vehicle 1 deviates from the power supply mat 23.

[0084] Figure 11 is a flowchart showing the processing procedure of the vehicle guidance process in Embodiment 3. This flowchart is different from the flowchart in Embodiment 1 (see Figure 6) in that it includes the processes of S63 and S74 instead of the processes of S23 and S24, and includes the process of S54. Other processes are the same as the corresponding processes in the flowchart of Embodiment 1.

[0085] When receiving a power supply request from Vehicle 1 (YES in S62), the controller 24 acquires the position deviation (deviation amount) of Vehicle 1 with respect to the power supply mat 23 at predetermined intervals (in this example, for each position of the power transmission coil 231) (S63). The controller 24 extracts, for example, the continuous temporal change in the traveling position of Vehicle 1 in the past (for example, during the period from several seconds ago to the present) by image recognition processing. The controller 24 can predict the continuous temporal change in the traveling position of Vehicle 1 in the future (for example, during the period from the present to several seconds later) when the operation by the driver remains unchanged. Since the position of the power supply mat 23 is known, the position deviation (deviation amount) of Vehicle 1 with respect to the power supply mat 23 can be calculated based on the future traveling position of Vehicle 1 and the position of the power supply mat 23.

[0086] However, the method for acquiring the position deviation of Vehicle 1 with respect to the power supply mat 23 is not particularly limited. The controller 24 can also calculate the position deviation of Vehicle 1, for example, by acquiring information such as the steering angle, vehicle speed, and acceleration of Vehicle 1 through communication with Vehicle 1. Further, the controller 24 may use a combination of the above-described image recognition processing and information such as the steering angle.

[0087] In S64, the controller 24 sets the emission color of the display layer 232 according to the position deviation of Vehicle 1 with respect to the power transmission coil 231 at predetermined intervals (for example, for each position of the power transmission coil 231). Since this process has been described in detail in FIGS. 10(A) and 10(B), the description will not be repeated.

[0088] On the other hand, in S54, the ECU 10 sets the display color of the power supply mat 23 on the HUD 192 according to the amount of displacement of the vehicle 1 with respect to the power transmission coil 231 (see Fig. 10(C)). The ECU 10 can calculate the amount of displacement of the vehicle 1 based on information such as the steering angle, vehicle speed, and acceleration of the vehicle 1, and set the display color of the power supply mat 23 according to the calculated amount of displacement. Note that the ECU 10 may detect the emission color of the display layer 232 of the power supply mat 23 by the camera 184, and set the display color of the power supply mat 23 on the HUD 192 according to the detected emission color. When the display layer 232 of the power supply mat 23 is blinking, the ECU 10 can also blink the display of the power supply mat 23 on the HUD 192. The ECU 10 may synchronize the blinking timing of the display on the HUD 192 with the blinking timing of the display layer 232.

[0089] As described above, also in the third embodiment, the display mode of the display layer 232 of the power supply mat 23 is controlled so as to guide the vehicle 1 according to the running state of the vehicle 1. More specifically, the display color of the display layer 232 is controlled according to the amount of displacement of the vehicle 1. Then, since the running position of the vehicle 1 deviates from the power supply mat 23 with the same vehicle operation, the driver can easily recognize that it is necessary to change the vehicle operation. Thereby, the vehicle 1 can run at an appropriate lateral position on the power supply mat 23. As a result, the power transmission efficiency from the power supply mat 23 to the power receiving device 16 can be improved.

[0090] The embodiments disclosed this time should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is shown not by the description of the above embodiments but by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

Explanation of Reference Numerals

[0091] 100 Non-contact charging system, 1 vehicle, 2 power supply system, 10 ECU, 101 processor, 102 memory, 11 battery, 110 monitoring unit, 12 SMR, 13 drive device, 131 converter, 132 inverter, 133 motor generator, 14 power converter, 151, 152 charging relay, 16 power receiving device, 161 power receiving coil, 17 inlet, 181 communication module, 182 receiver, 183 resolver, 184 camera, 19 HMI, 191 instrument panel, 192 HUD, 193 navigation screen, 21 power conversion device, 22 sensor unit, 23 power supply mat, 231 power transmission coil, 232 display layer, 24 controller, 800 charging connector, 900 AC power supply.

Claims

1. A power transmission device configured to transmit power to a power receiving coil mounted on a vehicle in a non-contact manner, a plurality of power transmission coils arranged in a predetermined direction on a road, A display unit provided on the plurality of power transmission coils, And a control unit configured to control a display mode of the display unit so as to guide the vehicle according to a traveling state of the vehicle. The control unit controls the display unit to emit light in a light emission pattern flowing in a traveling direction of the road when a traveling speed of the vehicle is lower than a specified speed of the road.

2. The power transmission device according to claim 1, wherein the control unit increases a flowing speed of the light emission pattern as the traveling speed of the vehicle is lower.

3. The control unit, When the vehicle is traveling with the power receiving coil shifted to the right side with respect to the plurality of power transmission coils, controls the display unit to display an icon or a message for causing the vehicle to move closer to the left side, while When the vehicle is traveling with the power receiving coil shifted to the left side with respect to the plurality of power transmission coils, controls the display unit to display an icon or a message for causing the vehicle to move closer to the right side. The power transmission device according to claim 1 or 2.

4. A power transmission device configured to transmit power to a power receiving coil mounted on a vehicle in a non-contact manner, a plurality of power transmission coils arranged in a predetermined direction on a road, A display unit provided on the plurality of power transmission coils, And a control unit configured to control a display mode of the display unit so as to guide the vehicle according to a traveling state of the vehicle. The control unit, In a section where a traveling position of the vehicle is maintained on the plurality of power transmission coils, controls the display unit to emit light in a first emission color, while In a section where the traveling position of the vehicle deviates from the plurality of power transmission coils, controls the display unit to emit light in a second emission color different from the first emission color.

5. A non-contact power transmission system comprising the power transmission device according to any one of claims 1 to 4 and the vehicle.

6. The vehicle includes a display device that provides information to a driver of the vehicle, and a control device that controls the display device, and the control device controls the display device to display a notification for adjusting a traveling position of the vehicle. The non-contact power transmission system according to claim 5.

7. The non-contact power transmission system according to claim 6, wherein the notification includes an icon for improving power transmission efficiency from the plurality of power transmission coils to the power reception coil.

8. The display device includes a head-up display, and the control device controls the head-up display to display the notification when the vehicle approaches within a predetermined distance from the power transmission device. The non-contact power transmission system according to claim 6 or 7.

9. A control method for a power transmission device including a plurality of power transmission coils configured to non-contact transmit power to a power reception coil mounted on a vehicle, comprising: detecting a traveling state of the vehicle; and guiding the vehicle by changing a display mode of a display unit provided on the plurality of power transmission coils according to the traveling state of the vehicle, wherein the guiding step includes displaying, on the display unit, a light emission pattern flowing in a traveling direction of the road when a traveling speed of the vehicle is lower than a specified speed of the road on which the plurality of power transmission coils are arranged. A control method for a power transmission device.

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