Electric Vehicles

Abstract

The present invention provides an electric vehicle capable of realizing control suitable for various situations, such as when non-contact power transmission is stopped due to foreign matter, it is preferable to quickly restart power transmission when the foreign matter is removed, or it is preferable to minimize power consumption during the power transmission stop process. The electric vehicle comprises: a main battery (11) for storing power for running; a power receiving unit (31) for non-contactly receiving power for charging the main battery from a power transmission device outside the vehicle; a communication unit (33) capable of communicating with the power transmission device; a charging control unit (34) for communicating with the power transmission device via the communication unit and controlling power transmission from the power transmission device to the power receiving unit. In addition, the charging control unit comprises: a confirmation processing unit (34a) for confirming whether the power transmission can be restarted when the power transmission is stopped based on the detection of a foreign matter; and a frequency control unit (34b) for changing the frequency of the confirmation processing unit's confirmation.

Description

Technical Field

[0001] The present invention relates to an electric vehicle having a power receiving unit for receiving electric power in a contactless manner. Background Art

[0002] In the past, there was a technology for transmitting power from ground equipment to an electric vehicle in a non-contact manner and charging the main battery of the electric vehicle. Such a technology is called non-contact charging. Patent document 1 shows the following technology: when a foreign object is present near the power transmission unit during non-contact charging, the non-contact charging is stopped, and then, if the foreign object is removed, the non-contact charging is restarted.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2013-223397 Summary of the invention

[0006] Technical issues

[0007] In the case where contactless charging is stopped due to detection of a foreign object, if the electric vehicle system stops, contactless charging cannot be restarted even if the foreign object is removed later. During contactless charging, the passenger often leaves the electric vehicle, so if contactless charging is stopped midway, the main battery may be barely charged when the passenger returns.

[0008] On the other hand, when non-contact charging is stopped due to foreign object detection, if the non-contact charging control operation is continued thereafter, the control system will continue to consume power while the power supply is stopped, which may exhaust the system power supply of the electric vehicle.

[0009] In addition, in the system configuration of electric vehicles, there are various configurations such as a configuration in which the power of the main battery storing power for running can be used as the power supply of the control system, and a configuration in which the vehicle cannot be started due to exhaustion of the power supply of the control system even if there is a remaining charge in the main battery. In addition, in the conditions for non-contact charging, there are various conditions such as a condition in which the charging of the main battery has a low priority and a condition in which exhaustion of the power supply of the control system can be quickly responded to.

[0010] The object of the present invention is to provide an electric vehicle that can realize control suitable for various situations, such as when non-contact power transmission is stopped due to foreign matter, it is best to quickly restart power transmission when the foreign matter is removed, or it is best to suppress power consumption as much as possible during the power transmission stop process.

[0011] Technical Solution

[0012] The first aspect of the invention is an electric vehicle, characterized in that it comprises: a main battery that stores electric power for running; a power receiving unit that receives electric power for charging the above-mentioned main battery from a power transmitting device outside the vehicle in a non-contact manner; a communication unit that can communicate with the above-mentioned power transmitting device; and a charging control unit that communicates with the above-mentioned power transmitting device via the above-mentioned communication unit and controls the power transmission from the above-mentioned power transmitting device to the above-mentioned power receiving unit, and the above-mentioned charging control unit has: a confirmation processing unit that confirms whether the above-mentioned power transmission can be restarted when the above-mentioned power transmission is stopped based on the detection of a foreign object; and a frequency control unit that can change the frequency of the confirmation performed by the above-mentioned confirmation processing unit.

[0013] The invention of a second aspect is characterized in that, in the electric vehicle according to the first aspect, the electric vehicle further includes a sub-battery that outputs a voltage lower than a voltage of the main battery, and the frequency control unit changes the frequency based on a state of the sub-battery.

[0014] The invention of a third aspect is the electric vehicle according to the first aspect or the second aspect, wherein the frequency control unit changes the frequency based on a total remaining amount of the electric vehicle.

[0015] The invention of the fourth aspect is characterized in that, in the electric vehicle described in any one of the first to third aspects, the electric vehicle further includes a request input unit for receiving a request from a user, and the frequency control unit changes the frequency based on the user's request input via the request input unit.

[0016] The invention according to a fifth aspect is the electric vehicle according to any one of the first aspect to the fourth aspect, wherein the frequency control unit changes the frequency based on the type of the detected foreign matter.

[0017] The invention of a sixth aspect is characterized in that, in the electric vehicle described in any one of the first aspect to the fifth aspect, the confirmation processing unit inquires the power transmission device via the communication unit to confirm whether the power transmission can be resumed.

[0018] The seventh aspect of the invention is characterized in that, in the electric vehicle described in any one of the first to fifth aspects, the electric vehicle further comprises a foreign object detection unit for detecting foreign objects, and the confirmation processing unit confirms whether the power transmission can be restarted based on the detection result obtained by the foreign object detection unit.

[0019] Technical Effects

[0020] According to the present invention, when non-contact power transmission is stopped based on detection of a foreign object, the confirmation processing unit confirms whether power transmission can be restarted. Therefore, for example, when the foreign object has been removed, power transmission can be restarted with the confirmation of the confirmation processing unit as a trigger. On the other hand, although the processing of the confirmation processing unit consumes power, the frequency of confirmation by the confirmation processing unit is changed by the frequency control unit, so that the amount of power consumed by the confirmation processing can be adjusted. Therefore, the control content can be adjusted according to various conditions, such as a condition in which it is best to quickly restart power transmission when the foreign object is removed, a condition in which it is desired to suppress power consumption as much as possible during the power transmission stop process, and the like. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a block diagram showing an electric vehicle and ground equipment according to Embodiment 1 of the present invention.

[0022] Figure 2 1 is a sequence diagram showing the flow of the non-contact charging process performed by the electric vehicle and the ground equipment according to the first embodiment.

[0023] Figure 3 It is shown Figure 2 Flowchart of a first example of frequency setting processing.

[0024] Figure 4 It is shown Figure 2 Flowchart of a second example of frequency setting processing.

[0025] Figure 5 It is shown Figure 2 Flowchart of a third example of frequency setting processing.

[0026] Figure 6 It is shown Figure 2 Flowchart of a fourth example of frequency setting processing.

[0027] Explanation of symbols

[0028] 1 Electric Vehicles

[0029] 3 Travel motor

[0030] 11 Main battery

[0031] 15 batteries

[0032] 31 Receiving unit

[0033] 33 Ministry of Communications

[0034] 34 Charging control unit

[0035] 34a Confirmation Processing Unit

[0036] 34b Frequency control unit

[0037] 38 Foreign matter detection unit

[0038] 39 Telematics service communication unit (request input unit)

[0039] 41 Control Department

[0040] 100 Ground Equipment

[0041] 103 Power Transmission Department

[0042] 104 Foreign matter detection department

[0043] 105 Power transmission control unit

[0044] 105a Foreign matter detection processing unit

[0045] 106 Ministry of Communications DETAILED DESCRIPTION

[0046] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0047] (Implementation Method 1)

[0048] Figure 1 This is a block diagram showing an electric vehicle and ground equipment according to Embodiment 1 of the present invention. The electric vehicle 1 according to Embodiment 1 is an EV (Electric Vehicle) or HEV (Hybrid Electric Vehicle) equipped with a contactless charging function. The electric vehicle 1 includes a driving wheel 2, a travel motor 3 that generates power for the driving wheel 2, a main battery 11 that stores power for travel, an inverter 12 that converts the power of the main battery 11 to drive the travel motor 3, a power receiving unit 31 that receives power contactlessly by electromagnetic action, a rectifier 32 that rectifies the power received by the power receiving unit 31, a sub-battery 15 that stores power for devices other than the travel motor 3, a DC / DC converter 23 that converts the power of the main battery 11 for use by the devices, a voltage regulator 16 that generates a power supply voltage of a control system from the power of the sub-battery 15, a control unit 41 that controls travel and various parts of the electric vehicle 1, a charging control unit 34 that controls contactless charging, a communication unit 33 that communicates with a ground device 100 during contactless charging, and a telematics service communication unit 39 that can communicate with a user's portable terminal via a telematics service. The telematics service communication unit 39 corresponds to an example of a request input unit of the present invention.

[0049] The ground equipment 100 is a power transmission equipment that transmits electric power to the electric vehicle 1 in a non-contact manner. The ground equipment 100 includes: a power transmission unit 103 that transmits electric power to the power receiving unit 31 of the electric vehicle 1 in a non-contact manner by electromagnetic action, an inverter 102 that receives electric power from a commercial power source and allows AC current to flow to the power transmission unit 103, a communication unit 106 that communicates with the electric vehicle 1 during non-contact charging, a power transmission control unit 105 that drives the inverter 102 and controls the power transmission from the power transmission unit 103, and a foreign object detection unit 104 that detects foreign objects near the power transmission unit 103 when the non-contact power transmission is stopped. The foreign object detection unit 104 may be any configuration as long as it can detect foreign objects in a state where a magnetic field is not generated from the power transmission unit 103, such as image recognition of foreign objects by shooting and shooting images, ultrasonic radar, optical radar, etc.

[0050] The main battery 11 is, for example, a lithium ion secondary battery, a nickel-metal hydride secondary battery, etc., and stores electric power for driving the travel motor 3. The main battery 11 outputs a high voltage for driving the travel motor 3, and may also be called a high-voltage battery. The main battery 11 may be connected to a high-voltage power supply line via a relay that is opened and closed by, for example, the control unit 41.

[0051] The sub-battery 15 is, for example, a lead storage battery, and supplies electric power to devices other than the travel motor 3. The sub-battery 15 outputs a power supply voltage (for example, 12 V) lower than the output voltage of the main battery 11.

[0052] The power receiving unit 31 and the power transmitting unit 103 are coils that transmit power contactlessly by, for example, electromagnetic induction or electromagnetic resonance. When the power receiving unit 31 and the power transmitting unit 103 are aligned, an alternating current is output to the power transmitting unit 103, thereby generating an alternating electromotive force in the power receiving unit 31.

[0053] The control unit 41 receives an operation signal of a driving operation performed by a passenger, and drives the inverter 12 and the like according to the operation signal to control the travel of the electric vehicle 1. Furthermore, the control unit 41 includes a battery management unit that manages the state information of the main battery 11. The battery management unit receives the state signal (discharge current, charge current, voltage, temperature, etc.) of the main battery 11, and manages the charge rate, etc. of the main battery 11. The control unit 41 provides the state information of the main battery 11 to the charging control unit 34 during non-contact charging. The provided state information includes information such as the charge rate (SOC: State Of Charge), temperature, and input limit power, which can calculate the requested power when charging the main battery 11. Furthermore, the control unit 41 receives an operation signal of a non-contact charging start button that can be operated by the passenger, and cooperates with the charging control unit 34 to perform the non-contact charging process. The control unit 41 can be composed of one ECU (Electronic Control Unit) or a plurality of ECUs that communicate with each other and act in cooperation.

[0054] The charging control unit 34 controls the contactless charging while communicating with the ground equipment 100 via the communication unit 33. The charging control unit 34 includes a confirmation processing unit 34a and a frequency control unit 34b. The confirmation processing unit 34a performs a confirmation process to determine whether the foreign object has been removed and the contactless charging can be restarted when the contactless charging (contactless power transmission) is stopped due to the detection of a foreign object, and the frequency control unit 34b sets the frequency of the confirmation process performed by the confirmation processing unit 34a. The charging control unit 34 may be composed of one ECU or a plurality of ECUs that communicate with each other and act in coordination. In addition, the ECU that functions as the charging control unit 34 and the ECU that functions as the control unit 41 do not need to be separate entities, and a configuration in which a common ECU realizes all or part of the functions of the charging control unit 34 and all or part of the functions of the control unit 41 may be adopted. The confirmation processing unit 34a and the frequency control unit 34b may also be functional modules realized by causing the CPU (Central Processing Unit: Central Processing Unit) in the ECU to execute a control program.

[0055] <Non-contact charging process>

[0056] Figure 2 1 is a sequence diagram showing the flow of the non-contact charging process performed by the electric vehicle and the ground equipment according to the first embodiment.

[0057] The charging control unit 34 cooperates with the power transmission control unit 105 to control the non-contact charging via communication. If the control unit 41 receives a non-contact charging start instruction based on the user's non-contact charging start operation, first, as shown in FIG. Figure 2 As shown in the start period T1 of the charging control unit 34, the charging control unit 34 performs the position alignment process J11 of the electric vehicle 1. In the position alignment process J11, the power transmission unit 103 is weakly excited, and the charging control unit 34 performs movement assistance of the electric vehicle 1 while measuring the electromotive force of the power reception unit 31. The user can align the positions of the power reception unit 31 and the power transmission unit 103 by moving the electric vehicle 1 according to the movement assistance. Through the position alignment, the electromagnetic effect of the weakly excited power transmission unit 103 is used to generate an electromotive force of a predetermined amount or more in the power reception unit 31, and the charging control unit 34 can determine the completion of the position alignment based on the electromotive force.

[0058] In the start period T1, if the positioning process J11 is completed, the charging control unit 34 sends a power transmission request to the power transmission control unit 105 through the wireless communication of the communication units 33 and 106. If power transmission is possible, the power transmission control unit 105 returns a positive response. Then, the process is transferred to the regular process J12 for actually performing power transmission.

[0059] In the periodic process J12, the charging control unit 34 calculates the appropriate charging power based on the state information of the main battery 11, and notifies the power request to the power transmission control unit 105. The power transmission control unit 105 causes the current to flow to the power transmission unit 103 via the inverter 102 so as to transmit the requested power, and transmits the power to the power reception unit 31 in a non-contact manner. The transmitted power is rectified by the rectifier 32 and transmitted to the main battery 11.

[0060] In the periodic processing J12, the foreign object detection processing unit 105a of the power transmission control unit 105 performs the foreign object detection processing J13. In the foreign object detection processing J13, for example, the power transmission control unit 105 receives the information of the power receiving amount from the charging control unit 34, and the foreign object detection processing unit 105a determines whether there is a foreign object based on the difference between the power transmission amount and the power receiving amount of the power transmission unit 103. Since the foreign object absorbs a part of the power transmitted non-contactly, the power transmitted to the power receiving unit 31 is reduced accordingly, so the presence or absence of foreign objects can be determined based on the difference between the power transmission amount and the power receiving amount. It should be noted that the detection method of foreign objects in the foreign object detection processing J13 is not limited to the above method. In the foreign object detection processing J13, various methods such as detecting the magnetic field change caused by foreign objects, image recognition of foreign objects using captured images, and detection using ultrasonic radar or optical radar can also be applied.

[0061] If there is no foreign matter, the periodic process J12 is repeatedly executed to advance the non-contact charging of the main battery 11 .

[0062] On the other hand, if a foreign object enters, it is determined in the foreign object detection process J13 that there is a foreign object, then Figure 2 As shown in the period T2 of , the power transmission control unit 105 notifies the charging control unit 34 of the presence of a foreign object, and based on the notification, the charging control unit 34 sends a request to stop power transmission to the power transmission control unit 105. Then, based on the request, the power transmission control unit 105 performs control to stop power transmission, and the power transmission from the power transmission unit 103 is stopped.

[0063] If the power transmission is stopped based on the detection of a foreign object, first, the frequency control unit 34b of the charging control unit 34 performs a frequency setting process J14. In the frequency setting process J14, the frequency control unit 34b sets the frequency of the process of confirming the removal of the foreign object by the confirmation processing unit 34a based on the remaining power of the electric vehicle 1 (the remaining charge status of the auxiliary battery 15, the main battery 11, or both), the user's request, the type of foreign object, or a plurality of them. The frequency control unit 34b may also include the status of the auxiliary battery 15 other than the remaining charge (e.g., voltage, SOH (State Of Health)) in the judgment factor to set the above frequency. For details of the frequency setting process, refer to Figure 3 to Figure 6 The flowchart is described later.

[0064] If the frequency is set, the confirmation processing unit 34a makes a foreign object inquiry to the power transmission control unit 105 at the set frequency in order to confirm whether the foreign object has been removed and the non-contact charging can be restarted. The foreign object inquiry is performed by wireless communication via the communication unit 33. Since the charging control unit 34 and the communication unit 33 operate using the power of the sub-battery 15, if the foreign object inquiry is repeated multiple times in the state where the non-contact charging is stopped, the charging rate of the sub-battery 15 will decrease.

[0065] As a result of the foreign object inquiry, the power transmission control unit 105 uses the foreign object detection unit 104 to determine whether there is a foreign object J15. If the foreign object has not been removed, a notification of the presence of a foreign object is sent back to the charging control unit 34. Such foreign object inquiry and notification of the presence of a foreign object are repeated until the foreign object is removed.

[0066] On the other hand, Figure 2 As shown in the period T3 of , when the foreign object is removed, a notification of the absence of foreign objects is sent from the power transmission control unit 105 to the charging control unit 34. As a result, the charging control unit 34 exits the repeated process of inquiring whether the foreign object has been removed, and sends a request to restart power transmission to the power transmission control unit 105. Then, if power transmission is possible, the power transmission control unit 105 returns an affirmative response to the charging control unit 34, and restarts the non-contact power transmission and charging of the main battery 11 through the above-mentioned periodic process J12.

[0067] <Frequency setting process>

[0068] Next, Figure 2 A specific example of the frequency setting process J14 is described below. Figure 3 It is shown Figure 2 The first example is a flowchart of a first example of frequency setting processing. The frequency control unit 34b sets the frequency to a high frequency if the remaining charge amount is large and sets the frequency to a low frequency if the remaining charge amount is small based on the remaining charge amount of the sub-battery 15.

[0069] if Figure 2 The frequency setting process J14 starts, and the frequency control unit 34b determines whether the remaining charge of the sub-battery 15 (or the output voltage indicating the remaining charge) is below the first threshold value where power exhaustion may occur (step S1A). If the result of the determination is "yes", the frequency control unit 34b sets the frequency to a long time such as 1 hour (step S2). On the other hand, if the result of the determination in step S1A is "no", the frequency control unit 34b sets the frequency to a short time such as 10 minutes (step S3).

[0070] Figure 3 The frequency setting process is useful when the system configuration of the electric vehicle 1 is such that if the sub-battery 15 is exhausted, the system of the electric vehicle 1 stops and cannot be restarted. Figure 3 The frequency setting process can restart the non-contact charging when the foreign matter has been removed, and when the remaining charge of the sub-battery 15 is small, the power consumption of the sub-battery 15 can be suppressed and the power of the sub-battery 15 can be suppressed. It should be noted that the frequency control unit 34b can also use other states such as the voltage or health state of the sub-battery 15 as a judgment factor to judge whether the power is likely to be exhausted or not, and set the frequency in the same manner based on the judgment result. In this case, the same effect as above is achieved.

[0071] Figure 4 It is shown Figure 2 The second example is a flowchart of a second example of frequency setting processing. The second example is an example in which the frequency control unit 34b sets the frequency to a high frequency if the remaining power is large and sets the frequency to a low frequency if the remaining power is low based on the total remaining power of the electric vehicle 1 (the total of the remaining charge of the main battery 11 and the remaining charge of the sub-battery 15).

[0072] if Figure 2The frequency setting process J14 starts, and the frequency control unit 34b determines whether the total remaining charge of the main battery 11 and the sub-battery 15 is less than the second threshold value where power exhaustion may occur (step S1B). If the result of the determination is "yes", the frequency control unit 34b sets the frequency to a long time such as 1 hour (step S2). On the other hand, if the result of the determination of step S1B is "no", the frequency control unit 34b sets the frequency to a short time such as 10 minutes (step S3).

[0073] Figure 4 The frequency setting process is useful when the system configuration of the electric vehicle 1 is such that the power of the main battery 11 is transferred to the sub-battery 15 via the DC / DC converter 23 or the like during contactless charging, or when the control system can be operated using the power of the main battery 11. Figure 4 The frequency setting process can restart the non-contact charging when the foreign matter has been removed, and can prevent the electric vehicle 1 from running out of power and causing the system to fail to start when the remaining power of the electric vehicle 1 is low. Figure 4 In the example of , the frequency control unit 34b may also use the voltage or health status of the sub-battery 15 or other conditions as the judgment factor, judge whether the power may be exhausted or not, and set the frequency in the same manner based on the judgment result. In this case, the same effect as above is achieved.

[0074] Figure 5 It is shown Figure 2 The third example is an example in which the frequency control unit 34b sets the frequency based on a user's request. The user's request may be a request that the user has pre-set in the electric vehicle 1, or a request that the user responds to each time an inquiry is made. The inquiry of the request is made through, for example, the telematics service communication unit 39 at the user's portable terminal. When inquiring about the request, the user may also be prompted with materials for judgment such as the status of the auxiliary battery 15 (e.g., remaining charge, voltage, health status), the remaining charge of the main battery 11, and the type of foreign matter.

[0075] if Figure 2 The frequency setting process J14 starts, and the frequency control unit 34b sends a notification to the user's portable terminal that a foreign object has been detected, and inquires about the frequency of the foreign object again (step S11). Then, the frequency control unit 34b waits for a response (step S12), and if there is a response ("Yes" in step S13), it sets the frequency to the frequency indicated by the user (step S14), and if there is no response, it sets the frequency to the frequency determined based on other conditions (step S15).

[0076] Figure 5The frequency setting process is useful when the user has proficiency to make appropriate situation judgments. Figure 5 The frequency setting process is performed. Since the inquiry process of foreign objects is performed at a frequency corresponding to the situation determined by the user, even if the non-contact charging is stopped due to the entry of foreign objects, it is possible to confirm the resumption of non-contact charging in accordance with the user's request, and restart non-contact charging with an appropriate lag time when the foreign object has been removed.

[0077] Figure 6 It is shown Figure 2 The fourth example is a flowchart of a fourth example of frequency setting processing. The fourth example is an example in which the frequency control unit 34b sets the frequency based on the type of foreign matter. Figure 2 The frequency setting process J14 starts, and the frequency control unit 34b determines whether the foreign object is a living organism (step S1C). The type of the foreign object is determined by the foreign object detection unit 104 or the foreign object detection processing unit 105a of the ground equipment 100, and the charging control unit 34 can identify it by receiving the information from the power transmission control unit 105 of the ground equipment 100. If the result of step S1C is "yes", the frequency control unit 34b sets the frequency to a short time such as 10 minutes (step S3). On the other hand, if the foreign object is not a living organism, the frequency control unit 34b sets the frequency to a long time such as 60 minutes (step S2).

[0078] according to Figure 6 The frequency setting process changes the frequency of the foreign object reconfirmation process according to whether the foreign object is a frequently moving object, thereby reducing useless power consumption and restarting the non-contact charging that was stopped due to the entry of the foreign object.

[0079] As described above, according to the electric vehicle 1 of the first embodiment, there are a confirmation processing unit 34a and a frequency control unit 34b, the confirmation processing unit 34a confirms whether the non-contact charging can be restarted due to the removal of foreign matter, and the frequency control unit 34b can change the frequency of the confirmation processing performed by the confirmation processing unit 34a. Therefore, after the non-contact charging is stopped due to the detection of foreign matter, in the case where the foreign matter is removed, etc., the non-contact charging can be restarted with the confirmation of the confirmation processing unit 34a as a trigger. On the other hand, although the processing of the confirmation processing unit 34a consumes power, the frequency of the confirmation processing of the confirmation processing unit 34a is changed by the frequency control unit 34b, so that the power consumed in the confirmation processing can be adjusted. Therefore, the control content can be adjusted according to various conditions, such as the situation where it is best to restart the non-contact charging quickly when the foreign matter is removed, and the situation where it is desired to suppress power consumption as much as possible during the non-contact charging stop process.

[0080] Furthermore, according to the electric vehicle 1 of embodiment 1, the confirmation processing unit 34a confirms whether the contactless charging can be restarted by inquiring the power transmission control unit 105 of the ground equipment 100 about foreign objects. Thus, even if the electric vehicle 1 does not have a foreign object detection mechanism, the contactless charging can be restarted by the electric vehicle 1 side rather than the ground equipment 100 side. Since the charging power and the like are managed according to the state of the main battery 11, it is more preferable to restart the contactless charging by the electric vehicle 1 than by the ground equipment 100. Furthermore, according to the above-mentioned structure, since there is no need for a foreign object detection mechanism in the electric vehicle 1, the cost of the electric vehicle 1 can be reduced.

[0081] (Implementation Method 2)

[0082] The electric vehicle 1 of the second embodiment includes, in addition to the components of the first embodiment, a foreign object detection unit 38 (in Figure 1 The foreign object detection unit 38 includes, for example, a photographing unit for photographing the lower portion of the power receiving unit 31 and a functional module for image recognition of the photographed image. The foreign object detection unit 38 is not limited to such a configuration, and various configurations such as a configuration using an ultrasonic radar or an optical radar to detect foreign objects may also be used.

[0083] In the electric vehicle 1 of the second embodiment, the confirmation processing unit 34a drives the foreign object detection unit 38 to confirm whether the foreign object has been removed, thereby inquiring the power transmission control unit 105 about the foreign object instead of the confirmation processing unit 34a. The foreign object detection unit 38 is driven by the power of the sub-battery 15. If the confirmation process of whether the foreign object has been removed is repeated a large number of times, the charging rate of the sub-battery 15 will decrease.

[0084] The frequency control unit 34 b sets the frequency of the confirmation process performed by the confirmation processing unit 34 a using the foreign object detection unit 38 according to various situations, similarly to the first embodiment.

[0085] Other components and processing contents are the same as those of the first embodiment.

[0086] According to the electric vehicle 1 of the second embodiment, the confirmation processing unit 34a can use the foreign object detection unit 38 to determine whether the foreign object has been removed, thereby determining whether the non-contact charging can be restarted. Therefore, during the non-contact charging stop process, the communication between the electric vehicle 1 and the ground equipment 100 can be temporarily cut off, and the power consumption during the interval of the confirmation processing can be further reduced.

[0087] The above describes the various embodiments of the present invention. However, the present invention is not limited to the above embodiments. For example, in the above embodiments, the frequency setting process is described as switching the frequency between two levels, but the frequency can also be switched between three or more levels. In addition, it is also possible to comprehensively consider Figure 3 to Figure 6 The frequency is switched according to two or more of the multiple conditions for switching the frequency shown. In addition, in the above-mentioned embodiment, an example is shown in which the frequency setting process is performed only once after the notification of the presence of foreign matter. However, the frequency setting process may be performed and the frequency of the confirmation process may be updated between repeated confirmation processes of whether the foreign matter has been removed. In addition, the details shown in the embodiment may be appropriately changed within the scope of the subject matter of the invention.

Claims

1. An electric vehicle, characterized in that: have: a main battery that stores electric power for traveling; a power receiving unit that receives power for charging the main battery in a contactless manner from a power transmitting device outside the vehicle; a communication unit capable of communicating with the power transmission device; as well as a charging control unit that communicates with the power transmitting device via the communication unit and controls power transmission from the power transmitting device to the power receiving unit, The charging control unit includes: a confirmation processing unit that confirms whether the power transmission can be restarted when the power transmission is stopped due to detection of a foreign object; as well as A frequency control unit is capable of changing a frequency at which the confirmation processing unit performs confirmation.

2. The electric vehicle according to claim 1, characterized in that: The electric vehicle further includes a sub-battery that outputs a voltage lower than a voltage of the main battery. The frequency control section changes the frequency based on a state of the sub-battery.

3. The electric vehicle according to claim 1, characterized in that: The frequency control section changes the frequency based on a total remaining amount of power of the electric vehicle.

4. The electric vehicle according to claim 2, characterized in that: The frequency control section changes the frequency based on a total remaining amount of power of the electric vehicle.

5. The electric vehicle according to claim 1, characterized in that: The electric vehicle further includes a request input unit for receiving a request from a user. The frequency control unit changes the frequency based on a user's request input via the request input unit.

6. The electric vehicle according to any one of claims 1 to 5, characterized in that: The frequency control unit changes the frequency based on the type of the detected foreign matter.

7. The electric vehicle according to any one of claims 1 to 5, characterized in that: The confirmation processing unit inquires the power transmitting device via the communication unit to confirm whether the power transmission can be resumed.

8. The electric vehicle according to claim 6, characterized in that: The confirmation processing unit inquires the power transmitting device via the communication unit to confirm whether the power transmission can be resumed.

9. The electric vehicle according to any one of claims 1 to 5, characterized in that: The electric vehicle further includes a foreign object detection unit for detecting foreign objects. The confirmation processing unit confirms whether the power transmission can be resumed based on the detection result obtained by the foreign object detection unit.

10. The electric vehicle according to claim 6, characterized in that: The electric vehicle further includes a foreign object detection unit for detecting foreign objects. The confirmation processing unit confirms whether the power transmission can be resumed based on the detection result obtained by the foreign object detection unit.

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