Vehicle and power feeding device

Abstract

To safely continue charging even when wireless communication between a vehicle side and a ground side is interrupted during noncontact power transmission between coils on the vehicle side and the ground side.SOLUTION: A vehicle comprises: a power reception coil which receives power transmitted in a non-contact manner from a power transmission coil on a ground side; a battery which stores power received by the power reception coil; a control device which executes charge control; and a communication device which performs wireless communication with a ground side device. The control device confirms a relation between the number of apparatuses using other frequency bands and field intensity before a communication abnormality with the ground side device occurs, ranks channels according to the confirmation result, and tries re-connection with the ground side device with which the communication is interrupted in order of the ranked channels when the communication with the ground side device is interrupted during charge.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a vehicle and a power supply device. [Background technology]

[0002] Patent document 1 discloses that in a contactless charging system that transmits power contactlessly from a ground-side power supply device to a vehicle, if communication between the ground-side device and the vehicle is interrupted during contactless charging, charging can be continued even in the communication-interrupted state by using information received during communication. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-030049 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the configuration described in Patent Document 1, even if communication is interrupted during charging, power transmission can be continued using the information obtained during communication. However, the reliability of the information decreases over time, increasing the risk of overcharging.

[0005] The present invention has been made in consideration of the above-mentioned circumstances, and aims to provide a vehicle and a power supply device that can continue charging safely even if wireless communication between the vehicle side and the ground side is interrupted during contactless power transmission between the vehicle side coil and the ground side coil. [Means for solving the problem]

[0006] The vehicle of the present invention is a vehicle equipped with a receiving coil that receives power transmitted contactlessly from a ground-side power transmission coil, a battery that stores the power received by the receiving coil, a control device that executes charging control to supply the power transmitted contactlessly from the transmitting coil to the receiving coil to the battery, and a communication device that performs wireless communication with a ground-side device configured to include the transmitting coil, wherein the control device checks the relationship between the number of devices using a frequency band other than the frequency band used for wireless communication with the ground-side device and the radio wave strength of the other frequency band before a communication abnormality occurs between the ground-side device and the communication device, and ranks the channels of the other frequency band according to the confirmation result, and when communication with the ground-side device is interrupted while charging with power supplied from the transmitting coil, attempts to reconnect with the ground-side device with which communication has been interrupted in the order of the ranked channels.

[0007] The power supply device of the present invention is a power supply device including a power transmission coil installed on the ground, a control device that controls power transmission in a contactless manner to transmit power from the power transmission coil to a power receiving coil mounted on a vehicle, and a communication device that performs wireless communication with the vehicle, wherein the control device checks the relationship between the number of devices using a frequency band other than the frequency band used for wireless communication with the vehicle and the radio wave intensity of the other frequency band before a communication abnormality occurs between the vehicle and the communication device, and ranks the channels of the other frequency band according to the confirmation result, and if communication with the vehicle is interrupted while power is being transmitted from the power transmission coil to the power receiving coil, attempts to reconnect with the vehicle with which communication has been interrupted in the order of the ranked channels. Effect of the Invention

[0008] In the present invention, charging can be continued safely even if wireless communication between the vehicle side and the ground side is interrupted during contactless power transmission between the vehicle side coil and the ground side coil. [Brief description of the drawings]

[0009] [Figure 1]1 is a schematic diagram showing a non-contact charging system according to an embodiment; [Diagram 2] FIG. 2 is an explanatory diagram showing frequency bands and channels. [Diagram 3] FIG. 4 is a flowchart showing a charging control flow. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] A vehicle and a power supply device according to an embodiment of the present invention will be specifically described below. Note that the present invention is not limited to the embodiment described below.

[0011] 1 is a schematic diagram showing a wireless charging system according to an embodiment. The wireless charging system 1 includes a ground-side device 2 and a vehicle 3. In the wireless charging system 1, power can be transmitted wirelessly from a coil in the ground-side device 2 to a coil in the vehicle 3 when the vehicle 3 is stopped.

[0012] The ground side device 2 is a ground facility that supplies power to the vehicle 3. For example, the ground side device 2 is installed in a parking lot of a commercial facility or a parking lot at home. The ground side device 2 includes a power supply device 10. The power supply device 10 is a device that transmits power to the vehicle 3 in a non-contact manner. An AC power source is connected to the power supply device 10. The AC power source is constituted by a commercial power source, a household power source, or the like, and supplies power to the power supply device 10.

[0013] The power supply device 10 includes a power transmission coil 11, a power transmission unit 12, a wall box 13, a power transmission ECU 14, and a communication device 15.

[0014] The power transmission coil 11 is a primary coil installed on the ground 4. The power transmission unit 12 is a device having the power transmission coil 11, and is installed on the ground 4 in the parking space together with the power transmission coil 11. The wall box 13 is installed near the parking space, for example, on the wall of the parking space. A power transmission ECU 14 and a communication device 15 are installed in the wall box 13. The power transmission unit 12 and the wall box 13 are electrically connected. Power is supplied to the power transmission unit 12 from an AC power source. In the power supply device 10, power from the AC power source is supplied to the power transmission unit 12 via a power conversion unit.

[0015] The power transmission ECU 14 is an electronic control device that controls the power supply device 10. The power transmission ECU 14 includes a processor and a memory. The processor is configured with a CPU, etc. The memory is configured with a RAM, a ROM, etc. Signals from various sensors are input to the power transmission ECU 14. The power transmission ECU 14 executes various controls based on the signals input from the various sensors. For example, the power transmission ECU 14 controls a switching element included in a power conversion unit of the power supply device 10 to adjust the power for transmission. In addition, the power transmission ECU 14 can execute power transmission control using information acquired by the communication device 15. This power transmission control is wireless power transmission control to the vehicle 3.

[0016] The communication device 15 performs wireless communication with the vehicle 3 parked in the parking space. The communication device 15 transmits information from the power transmission ECU 14 to the vehicle 3, and receives information transmitted from the vehicle 3. The communication device 15 is capable of wireless communication, for example, by Wi-Fi (registered trademark) or wireless LAN.

[0017] The vehicle 3 is an electric vehicle that can be charged with power transmitted contactlessly from the ground-side device 2. For example, the vehicle 3 is an electric vehicle (BEV), a hybrid vehicle (HEV), a plug-in hybrid vehicle (PHEV), etc. The vehicle 3 is a vehicle that can be parked in a parking space in which a power transmission coil 11 is installed.

[0018] The vehicle 3 includes a power receiving device 20, a power receiving coil 21, a battery 22, a vehicle ECU 23, and a communication device 24.

[0019] The power receiving device 20 has a power receiving coil 21 installed under the body of the vehicle 3. The power receiving coil 21 receives power transmitted contactlessly from the power transmitting coil 11. The power receiving device 20 supplies the power received from the power supply device 10 to a battery 22. The power supply device 10 and the battery 22 are electrically connected to each other.

[0020] The battery 22 is an on-board battery that can be externally charged. The battery 22 stores the power received by the power receiving device 20. The battery 22 is formed of a secondary battery that stores the power supplied from the power receiving device 20.

[0021] The vehicle ECU 23 is an electronic control device that controls the vehicle 3. The vehicle ECU 23 has a hardware configuration similar to that of the power transmission ECU 14. The vehicle ECU 23 executes various vehicle controls based on signals input from various sensors mounted on the vehicle 3 and information acquired through communication using the communication device 24. The vehicle controls include a charging control for storing power transmitted contactlessly from the power transmission unit 12 in the battery 22. The charging control is a control for transmitting power contactlessly from the power transmission coil 11 to the power receiving coil 21 and storing the power received by the power receiving coil 21 in the battery 22.

[0022] The communication device 24 performs wireless communication with an external device such as the ground device 2. The communication device 24 performs wireless communication with the communication device 15 of the power supply device 10 when the vehicle 3 performs contactless charging. The communication device 24 transmits information from the vehicle 3 to the power supply device 10 and receives information transmitted from the power supply device 10 to the vehicle 3.

[0023] When wireless communication by Wi-Fi (registered trademark) is performed between the ground side device 2 and the vehicle 3, the communication device 15 and the communication device 24 perform wireless communication using a channel for each predetermined frequency band, as shown in Fig. 2. In this case, there is a channel of a frequency band that does not interfere with every 5 channels, such as 1ch, 6ch, and 11ch. Therefore, when performing contactless charging, wireless communication can be established between the ground side device 2 and the vehicle 3 using any one of the channels 1ch, 6ch, and 11ch.

[0024] In the contactless charging system 1, in a state where wireless communication is established between the vehicle 3 and the power supply device 10, the power supply device 10 performs contactless charging of the vehicle 3. In a state where the vehicle 3 and the power supply device 10 are paired by wireless communication, power is transmitted contactlessly from the power transmission coil 11 on the ground side to the power receiving coil 21 on the vehicle side. In the vehicle 3, control is performed such that the power received by the power receiving coil 21 is supplied to the battery 22.

[0025] In the wireless charging system 1 configured as above, it is possible that wireless communication between the vehicle 3 and the ground side may be interrupted during wireless charging from the ground device 2 to the vehicle 3. If communication is interrupted during charging, charging can continue, but there is a risk of overcharging the battery 22. Therefore, the wireless charging system 1 is configured to quickly reconnect communication when communication is interrupted during charging, allowing charging to continue more safely.

[0026] 3 is a flowchart showing the charging control. The control shown in FIG.

[0027] The power transmission ECU 14 determines whether or not contactless charging from the ground device 2 to the vehicle 3 is being performed (step S1). In step S1, it is determined whether or not the power transmission ECU 14 is executing power transmission control.

[0028] When it is determined that the vehicle 3 is being charged wirelessly from the ground device 2 (step S1: Yes), the power transmission ECU 14 performs a communication check (step S2). The communication device 15 of the ground device 2 has a system for measuring the strength and congestion of the wireless connection. The congestion degree is used to grasp the number of wireless communication channels in use in the surrounding environment. In Wi-Fi (registered trademark), channel settings such as those shown in FIG. 2 are possible, and the communication device 15 can grasp how many devices are using which channel in the wireless communication environment. In step S2, the number of devices (the number of devices in use) using frequency bands of five channels that do not interfere with each other, such as 1ch, 6ch, and 11ch, in the vicinity of the ground device 2 is confirmed. In addition, the radio wave strength of the frequency bands of five channels that do not interfere with each other, such as 1ch, 6ch, and 11ch, in the vicinity of the ground device 2 is confirmed. Then, the relationship between the number of devices in use and the radio wave strength is confirmed for each channel (each predetermined frequency band). This relationship is expressed by the ratio of the number of devices in use to the radio wave strength. In step S2, the power transmitting ECU 14 checks the number of devices in use and the radio wave strength for each of 1ch, 6ch, and 11ch, and calculates a value obtained by dividing the number of devices in use by the radio wave strength. This calculated value is equal to the ratio of the number of devices in use to the radio wave strength. The smaller this value (ratio), the better the communication. The channel with the smallest ratio of the number of devices in use to the radio wave strength is the channel with the best communication. Furthermore, the power transmitting ECU 14 ranks the channels with the best communication. The power transmitting ECU 14 ranks the channels so that the channels with the smallest calculated ratios are ranked at the top.

[0029] The power transmission ECU 14 determines whether or not the communication state between the ground device 2 and the vehicle 3 is normal (step S3). In step S3, it is determined whether or not the wireless communication between the ground device 2 and the vehicle 3 has been interrupted.

[0030] If it is determined that the communication state between the ground device 2 and the vehicle 3 is normal (step S3: Yes), the power transmission ECU 14 continues the wireless charging from the ground device 2 to the vehicle 3 (step S4). After the process of step S4 is performed, this control routine ends.

[0031] If it is determined that the communication state between the ground device 2 and the vehicle 3 is not normal (step S3: No), the power transmission ECU 14 determines whether or not power transmission from the ground device 2 to the vehicle 3 may be continued (step S5). In step S5, it is determined whether or not the battery 22 will be overcharged. Using information acquired before the wireless communication between the ground device 2 and the vehicle 3 is interrupted, for example, the SOC of the battery 22, if the SOC is lower than the upper limit value of the SOC and has a margin, it can be determined that power transmission may be continued.

[0032] When it is determined that the power transmission from the ground side device 2 to the vehicle 3 may be continued (step S5: Yes), the power transmission ECU 14 reconnects the communication between the ground side device 2 and the vehicle 3 (step S6). In step S6, the communication between the ground side device 2 and the vehicle 3, which has been interrupted, is attempted to be reconnected in the order of the channels ranked in step S2. When the communication is restored from the interruption during charging, the power transmission ECU 14 attempts to reconnect the ground side device 2 and the vehicle 3, which has been interrupted, in the order of the channels ranked from the highest. For example, when 1ch is used for wireless communication between the ground side device 2 and the vehicle 3, the other frequency bands are 6ch and 11ch, which do not cause interference. The power transmission ECU 14 attempts to reconnect on 6ch if 6ch is ranked higher than 11ch according to the ranking in step S2, and attempts to reconnect on 11ch if 11ch is ranked higher than 6ch according to the ranking in step S2. Reconnection in a better communication state is attempted. Moreover, the process of step S2 is performed before a communication abnormality occurs between the ground side device 2 and the vehicle 3. Therefore, compared to a case where the relationship between the number of devices in use and the radio wave intensity for each channel is checked after the communication abnormality occurs and the channels are ranked based on the relationship, the calculation before the abnormality occurs as in step S2 can reduce the time until reconnection in step S6 is completed.

[0033] If it is determined that the power transmission from the ground device 2 to the vehicle 3 should not be continued (step S5: No), the power transmission ECU 14 stops charging by wireless power transmission from the ground device 2 to the vehicle 3 (step S7). In step S7, the power transmission from the power transmission coil 11 is stopped. After the process of step S7 is performed, this control routine ends.

[0034] If it is determined that contactless charging from the ground device 2 to the vehicle 3 is not being performed (step S1: No), this control routine proceeds to step S7.

[0035] As described above, according to the embodiment, since the communication check is completed before a communication abnormality occurs, it is possible to shorten the time until reconnection is completed after communication is interrupted. This makes it possible to shorten the communication interruption period during which there is a risk of overcharging. As a result, it is possible to reduce the risk of overcharging.

[0036] It should be noted that the power supply device 10 does not necessarily have to include the wall box 13. The power supply device 10 may be one in which the power transmission ECU 14 and the communication device 15 are installed on the ground 4 together with the power transmission unit 12.

[0037] The ground device 2 may be installed in a parking lot having a plurality of parking spaces. In this case, a power supply device 10 is installed for each parking space.

[0038] In addition, the Wi-Fi (registered trademark) channels may be any combination of five channels that do not interfere with each other, and are not limited to the combination of 1ch, 6ch, and 11ch. For example, the combination of 2ch, 7ch, and 12ch or the combination of 3ch, 8ch, and 13ch may be used.

[0039] 3 may be performed by the vehicle ECU 23, not limited to the power transmission ECU 14. For example, the vehicle ECU 23 may perform the processes of steps S1 to S7 shown in FIG. 3. In this case, the communication device 24 of the vehicle 3 has a system for measuring the strength of the wireless connection and the congestion degree. Furthermore, in step S5, the vehicle ECU 23 determines whether or not it is acceptable to continue receiving power from the ground device 2. [Explanation of symbols]

[0040] 1. Wireless charging system 2 Ground side equipment 3. Vehicle 4 ground 10 Power supply device 11. Transmission coil 12 Power transmission section 13 Wall Box 14 Power transmission ECU 15. Communications Equipment 20 Power receiving device 21 Receiving coil 22 Battery 23 Vehicle ECU 24 Communication Equipment

Claims

1. a receiving coil that receives power transmitted in a non-contact manner from a power transmitting coil on the ground; a battery that stores the power received by the power receiving coil; a control device that executes charging control to supply the battery with the electric power transmitted from the power transmitting coil to the power receiving coil in a non-contact manner; a communication device that performs wireless communication with a ground device configured to include the power transmitting coil; A vehicle equipped with The control device includes: Before a communication abnormality occurs between the ground side device and the communication device, a relationship between the number of devices using a frequency band other than a frequency band used for wireless communication with the ground side device and the radio wave intensity of the other frequency band is confirmed, and channels of the other frequency band are prioritized according to the confirmation result; When communication with the ground device is interrupted during charging with the power supplied from the power transmitting coil, reconnection with the ground device with which communication has been interrupted is attempted in the order of the ranked channels. A vehicle characterized by:

2. the relationship between the number of devices and the radio wave strength is expressed by a ratio of the number of devices to the radio wave strength, The control device includes: Calculating a ratio of the number of devices to the radio wave intensity for each of the other frequency bands, and ranking the channels corresponding to the other frequency bands in order of decreasing calculated ratio; When recovering from the interruption of the communication, an attempt is made to reconnect with the ground side device with which communication has been interrupted, in order from the highest ranked channel.

2. The vehicle according to claim 1 .

3. The control device checks the relationship between the number of devices and the radio wave intensity and prioritizes the channels before receiving power from the power transmitting coil after communication with the ground device is established.

3. The vehicle according to claim 2.

4. A transmission coil installed on the ground; a control device that controls power transmission in a non-contact manner from the power transmitting coil to a power receiving coil mounted on a vehicle; A communication device for wirelessly communicating with the vehicle; A power supply device comprising: The control device includes: Before a communication abnormality occurs between the vehicle and the communication device, a relationship between the number of devices using a frequency band other than a frequency band used for wireless communication with the vehicle and the radio wave intensity of the other frequency band is confirmed, and channels of the other frequency band are prioritized according to the confirmation result; When communication with the vehicle is interrupted during power transmission from the power transmitting coil to the power receiving coil, an attempt is made to reconnect with the vehicle with which communication has been interrupted in the order of the ranked channels. A power supply device characterized by:

5. the relationship between the number of devices and the radio wave strength is expressed by a ratio of the number of devices to the radio wave strength, The control device includes: Calculating a ratio of the number of devices to the radio wave intensity for each of the other frequency bands, and ranking the channels corresponding to the other frequency bands in order of decreasing calculated ratio; When recovering from the communication interruption, an attempt is made to reconnect with the vehicle with which communication has been interrupted, in order from the highest ranked channel. The power supply device according to claim 4 .

6. After communication with the vehicle is established, and before transmitting power from the power transmitting coil, the control device checks the relationship between the number of devices and the radio wave intensity and prioritizes the channels. The power supply device according to claim 5 .

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