WO2015121934A1

WO2015121934A1 - Wireless power transmission device, wireless power reception device, and wireless power transmission and reception system

Info

Publication number: WO2015121934A1
Application number: PCT/JP2014/053251
Authority: WO
Inventors: 浩喜工藤; 亜希子山田; 芙美杜塚
Original assignee: 株式会社東芝
Priority date: 2014-02-13
Filing date: 2014-02-13
Publication date: 2015-08-20
Also published as: JP6343292B2; JPWO2015121934A1

Abstract

[Problem] To propose a wireless power transmission device, a wireless power reception device, a wireless power transmission and reception system that, when detecting a foreign object, reduce the possibility of erroneously detecting a power transmission target as the foreign object. [Solution] The wireless power transmission device according to the present embodiment comprises a power transmission unit, a power transmission target detection unit, and a foreign object detection unit. The power transmission unit wirelessly transmits power to a power transmission target. The power transmission target detection unit detects that the power transmission target has entered a predetermined detection range including the power transmission unit. The foreign object detection unit detects a foreign object within the detection range, said foreign object preventing the power transmission unit from transmitting power. Based on the detection result of the power transmission target detection unit, the foreign object detection unit starts or terminates the foreign object detection.

Description

Non-contact power transmission device, non-contact power reception device, and non-contact power transmission / reception system

Embodiments of the present invention relate to a non-contact power transmission device, a non-contact power reception device, and a non-contact power transmission and reception system.

In the field of contactless power transmission where power is transmitted contactlessly from a power transmission device to a power reception device, foreign matter detection for detecting foreign matter present between the power transmission device and the power reception device is performed. The foreign matter causes a reduction in the power transmission efficiency, and also has a risk of generating heat during power transmission. Foreign object detection is particularly important when transmitting a large amount of power, such as an electric car. However, the conventional foreign matter detection method has a problem in that the power transmission target itself is erroneously detected as the foreign matter.

For example, as a foreign matter detection method for non-contact power transmission to an electric vehicle, the power transmission device recognizes the power reception device (electric vehicle) by communication means using a power transmission and reception coil, and detects a foreign object when the power reception device receives a response. Foreign object detection methods have been proposed. However, in the case of such a foreign matter detection method, since the communicable range of the communication means using the power transmission and reception coil is very narrow, the electric vehicle approaches the power transmission coil when the power transmission device recognizes the power reception device. There is a possibility that the electric vehicle is erroneously detected as a foreign object.

Further, as a foreign matter detection method for non-contact power transmission to an electric vehicle, there has been proposed a technique of changing the parameters to improve the foreign matter detection accuracy in foreign matter detection before and during power transmission. However, in the case of such a foreign matter detection method, there is still a possibility that the electric vehicle may be erroneously detected as a foreign matter if the parameter is not changed at an appropriate timing.

JP 2011-229265 A JP, 2013-59239, A

A non-contact power transmission device, a non-contact power reception device, and a non-contact power transmission and reception system are proposed, which reduce the possibility that a power transmission target is erroneously detected as a foreign object when detecting a foreign object.

The non-contact power transmission device according to the present embodiment includes a power transmission unit, a power transmission target detection unit, and a foreign matter detection unit. The power transmission unit transmits power without contact to the power transmission target. The power transmission target detection unit detects that the power transmission target has entered a predetermined detection range including the power transmission unit. The foreign matter detection unit detects foreign matter that interferes with power transmission by the power transmission unit within the detection range. The foreign matter detection unit starts or ends the detection of the foreign matter based on the detection result by the power transmission target detection unit.

FIG. 1 is a block diagram showing a configuration of a non-contact power transmission and reception system according to a first embodiment. BRIEF DESCRIPTION OF THE DRAWINGS The block diagram which shows the structure of the non-contact power transmission apparatus which concerns on 1st Embodiment. The block diagram which shows the other example of a structure of the non-contact power transmission apparatus which concerns on 1st Embodiment. The block diagram which shows the other example of a structure of the non-contact power transmission apparatus which concerns on 1st Embodiment. FIG. 1 is a block diagram showing a configuration of a non-contact power reception device according to a first embodiment. The figure which shows the specific example of the non-contact power transmission and reception system which concerns on 1st Embodiment. FIG. 7 is a block diagram showing another example of the configuration of the non-contact power reception device according to the first embodiment. FIG. 7 is a block diagram showing another example of the configuration of the non-contact power reception device according to the first embodiment. The transition diagram which shows an example of the transition of the operation state of the non-contact power transmission apparatus which concerns on 1st Embodiment. FIG. 7 is a transition diagram showing an example of transition of the operation state of the foreign matter detection unit according to the first embodiment. 3 is a flowchart showing the operation of the non-contact power transmission and reception system according to the first embodiment. 3 is a flowchart showing the operation of the non-contact power transmission and reception system according to the first embodiment. 3 is a flowchart showing the operation of the non-contact power transmission and reception system according to the first embodiment. 3 is a flowchart showing the operation of the non-contact power transmission and reception system according to the first embodiment. 3 is a flowchart showing the operation of the non-contact power transmission and reception system according to the first embodiment. 3 is a flowchart showing the operation of the non-contact power transmission and reception system according to the first embodiment. 3 is a flowchart showing the operation of the non-contact power transmission and reception system according to the first embodiment. 3 is a flowchart showing the operation of the non-contact power transmission and reception system according to the first embodiment. 3 is a flowchart showing the operation of the non-contact power transmission and reception system according to the first embodiment. 3 is a flowchart showing the operation of the non-contact power transmission and reception system according to the first embodiment. The transition diagram which shows an example of the transition of the operation state of the non-contact power transmission apparatus which concerns on 2nd Embodiment. The flowchart which shows operation | movement of the non-contact power transmission and reception system which concerns on 2nd Embodiment. The block diagram which shows the structure of the non-contact power transmission apparatus which concerns on 3rd Embodiment. The flowchart which shows operation | movement of the non-contact power transmission and reception system which concerns on 3rd Embodiment. The block diagram which shows the structure of the non-contact power transmission apparatus which concerns on 4th Embodiment. The flowchart which shows operation | movement of the non-contact power transmission and reception system which concerns on 4th Embodiment. The flowchart which shows operation | movement of the non-contact power transmission and reception system which concerns on 5th Embodiment. The block diagram which shows the structure of the non-contact power transmission apparatus which concerns on 6th Embodiment. The flowchart which shows operation | movement of the non-contact power transmission and reception system which concerns on 6th Embodiment. The block diagram which shows the structure of the non-contact power transmission and reception system which concerns on 7th Embodiment. The flowchart which shows operation | movement of the non-contact power transmission and reception system which concerns on 7th Embodiment.

Hereinafter, embodiments of the non-contact power transmission and reception system will be described with reference to the drawings. A non-contact power transmission and reception system is configured of a non-contact power transmission device for transmitting power without contact to a power transmission target and a non-contact power reception device mounted on the power transmission target. The non-contact power transmission and reception system can be applied to, for example, a parking lot for charging an electric vehicle such as a parked electric vehicle, an EV bus, or an EV taxi in a non-contact manner, or an industrial production line. In the case of a parking lot, the non-contact power transmission device is installed in the parking lot, and the non-contact power reception device is mounted on an electric vehicle to be transmitted. Further, in the case of a manufacturing line, the non-contact power transmission device is installed on a conveyance path such as a belt conveyor, and the non-contact power reception device is mounted on a power transmission target (product) conveyed by a belt conveyor or the like.

The non-contact power transmission device may be used alone. For example, it can be used to transmit power to a power receiving means provided with a corresponding power transmission method other than the non-contact power receiving device according to the present embodiment. Similarly, the non-contact power reception device may be used alone. For example, it can be used to receive power from power transmission means provided with a corresponding power transmission method other than the non-contact power transmission device according to the present embodiment. In the following description, the non-contact power transmission device, the non-contact power reception device, and the non-contact power transmission and reception system are respectively referred to as a power transmission device, a power reception device, and a power transmission and reception system.

First Embodiment
The power transmission and reception system according to the first embodiment will be described below with reference to FIGS. 1 to 20. Here, FIG. 1 is a block diagram showing a configuration of a power transmission and reception system according to the present embodiment. As shown in FIG. 1, the power transmission and reception system according to this embodiment includes a power transmission device 100 that transmits power without contact and a power reception device 200 that receives power without contact.

The power transmission device 100 is a device for contactlessly transmitting power to a power transmission target. Here, FIG. 2 is a block diagram showing a configuration of the power transmission device 100 according to the present embodiment. As shown in FIG. 2, the power transmission apparatus 100 includes a power transmission unit 101 that performs non-contact power transmission, a first power transmission target detection unit 104 that detects a power transmission target, and a foreign matter detection unit 105 that detects a foreign object that interferes with power transmission. A power transmission control unit 106 that controls the power transmission device 100 and a communication unit 107 that communicates with the power reception device 200 are provided.

The power transmission unit 101 transmits power without contact to power reception means of a power reception system corresponding to the power transmission system of the power transmission unit 101. In the present embodiment, the power transmission method of the power transmission unit 101 corresponds to the power reception method of the power reception unit 201 of the power reception device 200. The power transmission unit 101 can transmit power without being limited to the power reception unit 201 as long as the power reception unit of the power reception method corresponding to the power transmission method of the power transmission unit 101 is used. The power transmission method of the power transmission unit 101 of FIG. 2 is a magnetic field resonance method. The power transmission unit 101 includes a power transmission circuit 102 and a power transmission coil 103.

The power transmission circuit 102 is connected to the power supply 110, and converts the power supplied from the power supply 110 into a frequency or voltage suitable for power transmission. The power source 110 may be a system power source such as AC 100 V or AC 200 V, or may be a storage battery or a storage facility. A configuration in which the power supply 110 is included in the power transmission unit 101 is also possible. The power transmission circuit 102 can be configured by, for example, a power factor adjustment circuit or a high frequency inverter.

The power transmission coil 103 is a magnetic field emission type power antenna. The power transmission coil 103 is supplied with power from the power transmission circuit 102, and performs non-contact power transmission by LC resonance. The power transmission coil 103 achieves high power transmission efficiency at a specific frequency.

The power transmission method of the power transmission unit 101 is not limited to the magnetic field resonance method, and any existing power transmission method such as an electromagnetic induction method or a radio wave method can be adopted. FIG. 3 is a block diagram showing an example of the power transmission unit 101 adopting another power transmission method. As shown in FIG. 3, the power transmission unit 101 includes a power transmission antenna 103 instead of the power transmission coil 103. As the power transmission antenna 103, a rectifying antenna or an antenna for electric field coupling can be used.

The first power transmission target detection unit 104 detects that the power transmission target has entered the first detection range. The first detection range is a range predetermined to detect that the power transmission target approaches the power transmission range that can be transmitted by the power transmission unit 101 (the power transmission coil 103), and is set to include the power transmission range. . Further, the first detection range is set wider than the false detection range so as to include the false detection range described later. The foreign matter detection unit 105 starts the foreign matter detection processing at the timing when the power transmission target enters the first detection range.

In order to detect that the power transmission target has entered the first detection range, the first power transmission target detection unit 104 can detect the power transmission target in part or all of the surroundings of the first detection range. One or more are provided. When the approach direction of the power transmission target is determined in advance, one first power transmission target detection unit 104 may be installed in the approach direction of the first detection range. For example, various detection means such as an infrared sensor, an ultrasonic sensor, and a weight sensor can be used as the first power transmission object detection unit 104. Also, the function of the first power transmission target detection unit 104 can be realized using the communication unit 107 described later. The detection method of the power transmission target using the communication unit 107 will be described later. The configuration of the first power transmission target detection unit 104 is not limited to these, and may be any configuration that can detect that the power transmission target has entered the first detection range.

The foreign matter detection unit 105 detects a foreign matter that interferes with the power transmission by the power transmission unit 101. The foreign matter includes an object that reduces the power transmission efficiency by the power transmission unit 101, a metal that may generate heat, and the like. As the foreign matter detection unit 105, various sensors and detection methods such as a CMOS image sensor such as a camera, an ultrasonic sensor, an infrared sensor, and a capacitive sensor used for a touch panel such as a smartphone can be used. The foreign matter detection unit 105 starts the foreign matter detection processing based on the detection result of the first power transmission target detection unit 104. The foreign matter detection processing by the foreign matter detection unit 105 will be described later.

The foreign substance detection unit 105 may be configured by one sensor or detection method, or may be configured by combining a plurality of sensors or detection methods. For example, as shown in FIG. 4, the power transmission apparatus 100 may include a foreign matter detection unit 105A used for foreign matter detection processing before power transmission and a foreign matter detection unit 105B used for foreign matter detection processing during power transmission.

In this case, it is conceivable to use a magnetic field sensor such as a metal detector as the foreign matter detection unit 105A. When the power transmission target approaches, the magnetic field sensor may erroneously detect the power transmission target as a foreign object due to the metal contained in the power transmission target, or the detection accuracy of the foreign object may be deteriorated due to the magnetic field generated during power transmission. . However, in the foreign object detection before power transmission, since the power transmission target is separated from the foreign object detection unit 105, the foreign object can be detected with high accuracy.

Moreover, it is possible to use an ultrasonic sensor etc. which can detect a foreign substance also during power transmission as foreign substance detection part 105B. As described above, foreign matter detection can be performed with high accuracy by using the foreign matter detection unit of the foreign matter detection method which is different before and during power transmission. In addition, a configuration is also possible in which foreign matter detection can be performed with high accuracy by using the same foreign matter detection method before power transmission and during power transmission and changing the parameter for foreign matter detection.

The foreign matter detection unit 105 sets an erroneous detection range in advance. The erroneous detection range is a range in which the foreign object detection unit 105 may erroneously detect the power transmission object as a foreign object when the power transmission object enters the range. The erroneous detection range can be set, for example, by the relative position (relative distance) from the foreign matter detection unit 105 or the power transmission unit 101 (power transmission coil 103).

More specifically, the false detection range is, for example, false in the case where the foreign matter detection unit 105 detects a foreign matter before power transmission during practical use or a test, but the foreign matter detection unit 105 does not detect a foreign matter during power transmission. It can be defined as detection and can be set based on the erroneously detected relative position information of the power transmission target. For example, a plurality of pieces of relative position information of the power transmission object erroneously detected by the above-described method can be acquired, and a range inside the average value or the maximum value of the acquired relative positions (relative distances) can be set as the erroneous detection range . The erroneous detection range can sequentially update the relative position information of the erroneously detected power transmission target, and can update the foreign matter detection range based on the updated relative position information.

The erroneous detection range can also be set in accordance with the specification of the sensor and detection method that constitute the foreign matter detection unit 105. In any case, the false detection range is preferably set to include the power transmission range. The erroneous detection range set in this manner may be stored in advance as a table.

The power transmission control unit 106 controls the operation of the power transmission device 100 based on the signals acquired from the respective components of the power transmission device 100. The power transmission control unit 106 causes the foreign object detection unit 105 to start the foreign object detection processing based on, for example, the power transmission object detection signal received from the first power transmission object detection unit 104. Also, for example, the power transmission control unit 106 causes the power transmission unit 101 to stop power transmission based on the foreign matter detection signal received from the foreign matter detection unit 105. The transmission control unit 106 can be realized by using a central processing unit (CPU), a digital signal processor (DSP), a field-programmable gate array (FPGA), or the like as basic hardware.

The communication unit 107 is connected to the transmission control unit 106, and enables wireless communication between the power transmission control unit 106 and an external device such as the power receiving device 200. As the communication unit 107, any existing wireless communication means such as a wireless LAN including Wi-Fi (registered trademark) or Bluetooth (registered trademark) can be used. The power transmission device 100 can also acquire relative position information of the power transmission target by communicating with the power transmission target via the communication unit 107. By comparing the relative position information of the power transmission target with the first detection range, the power transmission device 100 can detect that the power transmission target has entered the first detection range. That is, the function of the first power transmission target detection unit 104 can be realized using the communication unit 107.

The power receiving device 200 is a device for receiving power without contact from the power transmission unit. The power receiving device 200 can charge the received power to a load such as a battery or can supply the power to an external device as motive power. Here, FIG. 5 is a block diagram showing a configuration of the power receiving device 200 according to the present embodiment. As shown in FIG. 5, the power receiving apparatus 200 includes a power receiving unit 201 that receives power without contact, a power receiving control unit 204 that controls the power receiving apparatus 200, and a communication unit 205 that communicates with the power transmission apparatus 100.

The power reception unit 201 receives power without contact from the power transmission unit of the power transmission method corresponding to the power reception method of the power reception unit 201. As described above, the power reception method of the power reception unit 201 and the power transmission method of the power transmission unit 101 correspond to each other. The power reception unit 201 can receive power without being limited to the power transmission unit 101 as long as the power transmission unit of the power transmission method corresponding to the power reception method of the power reception unit 201 is used. The power reception method of the power reception unit 201 in FIG. 5 is a magnetic field resonance method. The power receiving unit 201 includes a power receiving coil 202 and a power receiving circuit 203.

The power receiving coil 202 is a magnetic field emission type power antenna. The power receiving coil 202 is supplied with power from the power transmitting coil 100 and receives power without contact by LC resonance. The power receiving coil 202 achieves high power reception efficiency at a specific frequency.

The power receiving circuit 203 is connected to the load 206, and converts the power supplied through the power receiving coil 202 into a frequency or voltage suitable for charging. The load 206 is, for example, a battery. A configuration in which the load 206 is included in the power receiving unit 201 is also possible. The power receiving circuit 203 converts the power supplied via the power receiving coil 202 into a direct current when the frequency suitable for charging is 0 Hz, that is, a direct current. In this case, the power receiving circuit 203 can be configured by a rectifier and a DC / DC converter.

The power reception method of the power reception unit 201 is not limited to the magnetic field resonance method, and may be an electromagnetic induction method or a radio wave method. The power receiving unit 201 may include a power receiving antenna instead of the power receiving coil 202. As the power receiving antenna, a rectifying antenna or an antenna for electric field coupling can be used.

The power reception control unit 204 controls the operation of the power reception device 200 based on the signal acquired from each component of the power reception device 200. The power reception control unit 204 can also transmit and receive a signal to / from the control unit of the power transmission target on which the power reception device 200 is mounted. Thereby, for example, the power reception control unit 204 acquires various types of information on the power transmission target from the control unit, generates a signal based on the acquired information, and transmits the signal to an external device such as the power transmission apparatus 100 via the communication unit 205. You can do it. The reception control unit 204 can be realized by using a central processing unit (CPU), a digital signal processor (DSP), a field-programmable gate array (FPGA), or the like as basic hardware.

The communication unit 205 is connected to the reception control unit 204, and enables wireless communication between the power reception control unit 204 and an external device such as the power transmission device 100. As the communication unit 205, any existing wireless communication means such as a wireless LAN including Wi-Fi, Bluetooth, etc. can be used.

FIG. 6 is a view showing a specific example in which the power transmission and reception system according to the present embodiment is applied to a parking lot for charging an electric vehicle. In FIG. 6, the power transmission target is an electric vehicle, the power transmission device 100 is installed in a parking lot, and the power reception device 200 is mounted in the electric vehicle.

The electric vehicle is parked in a parking space indicated by a white line in FIG. The power transmission coil 103 is installed in the parking lot so that power can be transmitted to the power reception coil 202 of the parked electric vehicle, and transmits power to the power reception coil 202 located on the power transmission range. Foreign matter detection unit 105 detects foreign matter present in a range including the power transmission range of power transmission coil 103. The first power transmission target detection unit 104 detects that the electric vehicle has entered a first detection range including the erroneous detection range of the foreign matter detection unit 105.

As shown in FIG. 6, when the power transmission device 100 is installed in a parking lot, the configuration of the first power transmission target detection unit 104 may be realized by a ticket issuing device of a parking ticket. In this case, the first detection range is in a parking lot inside the ticket issuing device, and the ticket issue signal of the parking ticket transmitted from the ticket issuing device can be used as a power transmission target detection signal. In addition, in FIG. 6, only the receiving coil 202 is shown in figure, and the other structure is abbreviate | omitted.

As described above, when the power transmission target is an electric vehicle, as shown in FIG. 7, the power reception control unit 204 and an ECU (Engine Control Unit) 207 that is a control unit of the electric vehicle include predetermined ones such as CAN-BUS. It may be connected via the interface of With such a configuration, the power reception control unit 204 can acquire various types of information regarding the electric vehicle from the ECU. The information acquired by the power reception control unit 204 includes information on the traveling speed of the electric vehicle and information indicating that the electric vehicle has stopped. The power reception control unit 204 can generate a signal based on these pieces of information, and can transmit the signal to an external device such as the power transmission device 100 via the communication unit 205.

Moreover, the structure by which the communication part 205 was connected to ECU207 is also possible. In this case, the power reception control unit 204 transmits the generated signal to an external device via the communication unit 205 connected to the ECU 207. Furthermore, as shown in FIG. 8, a configuration in which the function of the power reception control unit 204 is realized by the ECU 207 is also possible.

Next, the operation of the power transmission and reception system according to the present embodiment will be described with reference to FIGS. 9 to 20. In the following, when the power transmission and reception system is applied to a parking lot for charging an electric vehicle as in FIG. 6, that is, the power transmission target is the electric vehicle, the power transmission device 100 is installed in the parking lot, and the power reception device 200 is The case of being mounted on an electric vehicle will be described. However, as described above, the power transmission and reception system is applicable not only to the parking lot but also to other applications.

First, the transition of the operation state of the power transmission control unit 106 will be described with reference to FIG. FIG. 9 is a transition diagram showing an example of the transition of the operation state of the power transmission control unit 106 according to the present embodiment. As shown in FIG. 9, the power transmission control unit 106 is in the standby state M1 until the electric vehicle approaches the parking lot. In the standby state M1, the first power transmission target detection unit 104 executes power transmission target detection processing. In the standby state M1, the foreign matter detection unit 105 may or may not perform the foreign matter detection process, but it is preferable that the foreign matter detection process is not performed. Thereby, the power consumption of the power transmission device 100 can be reduced. When the first power transmission target detection unit 104 detects a power transmission target, the power transmission control unit 106 transitions to the pre-power transmission foreign object detection state M2.

In the pre-transmission foreign object detection state M2, the foreign object detection unit 105 executes a foreign object detection process (pre-transmission foreign object detection process). The foreign object detection process before power transmission is performed for a predetermined duration. The duration is set such that the foreign object detection processing before power transmission ends before the power transmission target enters the erroneous detection range. Instead of the duration, the number of foreign object detections may be set such that the foreign object detection processing before power transmission ends before the power transmission target enters the erroneous detection range. In the foreign object detection state before power transmission M2, the first power transmission target detection unit 104 may or may not execute the power transmission target detection process.

In the foreign object detection state M2 before power transmission, when the foreign object detection unit 105 detects a foreign object, the power transmission control unit 106 transitions to the power transmission impossible state M3. In the power transmission impossible state M3, the power transmission unit 101 does not perform power transmission even if the electric vehicle is parked in the parking space. The power transmission device 100 may perform foreign object detection notification to notify the driver of the electric vehicle of the presence of the foreign object. The foreign matter detection and notification method will be described later. The power transmission impossible state M3 continues until the foreign matter detected by the foreign matter detection unit 105 is removed. In the power transmission impossible state M3, when the foreign matter detected by the foreign matter detection unit 105 is removed, the power transmission control unit 106 transitions to the standby state M1.

In the foreign object detection state M2 before power transmission, the foreign object detection unit 105 may continue the foreign object detection process. In this case, the power transmission control unit 106 determines that the foreign matter has been removed when the foreign matter detection unit 105 no longer detects the foreign matter, and transitions to the standby state M1. The foreign matter detection processing in the foreign matter detection state M2 before power transmission may be continued until the foreign matter is removed, or may be continued for a predetermined time. Power consumption of the power transmission device 100 can be reduced by limiting the duration of the foreign matter detection process to a predetermined time.

In the foreign matter detection state M2 before power transmission, the foreign matter detection unit 105 may end the foreign matter detection processing. In this case, the power transmission device 100 may be provided with a foreign matter removal notification unit for notifying that the driver of the electric vehicle has removed the foreign matter. The foreign matter removal notification means will be described later. When the foreign matter is removed in the power non-transferable state M3, the power transmission control unit 106 may transition to the power transmittable state M4 instead of the standby state M1.

In the foreign object detection state M2 before power transmission, when the foreign object detection unit 105 does not detect a foreign object, the power transmission control unit 106 transitions to the power transmittable state M4. In the power transmittable state M4, the power transmission unit 101 performs power transmission when the electric vehicle is parked in the parking space. The power transmittable state M4 continues until the electric car is parked in the parking space, more specifically, until the power receiving coil 202 of the power receiving device 200 mounted on the electric car is positioned on the power transmission range. When the power transmission control unit 106 transitions to the power transmittable state M4, the foreign matter detection unit 105 ends the foreign matter detection processing. The foreign object detection process is started when the electric vehicle enters the first detection range, and the foreign object detection unit 105 erroneously detects the electric vehicle as a foreign object by ending the foreign object detection process before entering the false detection range. The possibilities can be reduced. When a foreign object is detected, the power transmission control unit 106 transitions to the power transmission impossible state M3 and power transmission is not performed. Therefore, power transmission efficiency can be prevented safely and power transmission can be performed safely. In the power transmittable state M4, when the electric vehicle is parked in the parking space, the power transmission control unit 106 transitions to the power transmission state M5.

In the power transmission state M5, first, the foreign object detection unit 105 starts foreign object detection processing (foreign object detection processing during power transmission), and when no foreign object is detected, the power transmission unit 101 starts power transmission to the electric vehicle. That is, as shown in FIG. 10, the operation state of the foreign object detection unit 105 is the foreign object detection state before power transmission detection state m1 (the foreign object detection state before power transmission in the power transmission control unit 106) and the foreign object during power transmission. The foreign object detection state m2 (power transmission state M5 in the power transmission control unit 106) performing the detection process and the foreign object detection stop state m3 (power transmittable state M4 in the power transmission control unit 106) are not executed. Transition.

The foreign object detection unit 105 may execute the foreign object detection process by the same method in the foreign object detection state m1 before power transmission and the foreign object detection state m2 during power transmission, or may perform the foreign object detection processing by a different method. For example, the foreign matter detection unit 105 may perform foreign matter detection using different sensors before power transmission and during power transmission, or uses the same sensor before power transmission and during power transmission, and differs as a parameter for detecting foreign substances. Parameters may be used. As described above, foreign matter can be detected more accurately by changing the foreign matter detection method before power transmission and during power transmission.

In the power transmission state M5, when the foreign object detection unit 105 detects a foreign object, the power transmission control unit 106 transitions to the power transmission impossible state M3. On the other hand, in the power transmission state M5, when charging of the battery of the electric vehicle is completed without detecting the foreign object, the power transmission portion 101 ends power transmission, and the operation state of the power transmission control portion 106 transitions to the standby state M1. Do.

Next, a specific example of the operation of the power transmission and reception system will be described with reference to FIGS. 11 to 20. Here, FIG. 11 is a flowchart showing an operation of the power transmission and reception system until the operation state of the power transmission control unit 106 transitions from the standby state M1 to the power transmission impossible state M3 or the power transmission possible state M4. In the standby state M1, as described above, the power transmission target detection process is executed by the first power transmission target detection unit 104. Further, in FIG. 11, it is assumed that the electric vehicle is traveling.

When the traveling electric vehicle enters the first detection range, the first power transmission object detection unit 104 detects that the electric vehicle has entered the first detection range (step S1), and transmits the power transmission object detection signal. It transmits to the control part 106 (step S2). When the power transmission control unit 106 receives the power transmission target detection signal (step S3), the power transmission control unit 106 transitions to the foreign object detection state M2 before power transmission.

In the pre-transmission foreign object detection state M2, the power transmission control unit 106 transmits a pre-transmission foreign object detection start signal to the foreign object detection unit 105 (step S4). When receiving the pre-power transmission foreign object detection start signal, the foreign object detection unit 105 starts the pre-power transmission foreign object detection process (step S5), and transmits the result of the foreign object detection to the power transmission control unit 106 (step S6). After transmitting the detection result, the foreign matter detection unit 105 stands by for a predetermined time (step S7), and transmits the detection result to the power transmission control unit 106 again. That is, when the foreign object detection unit 105 starts the foreign object detection process before power transmission, the foreign object detection unit 105 transmits the detection result to the power transmission control unit 106 at predetermined time intervals.

The power transmission control unit 106 receives the detection result from the foreign matter detection unit 105 (step S8), and transitions to the power transmission impossible state M3 when the foreign matter is detected (Yes in step S9). On the other hand, when no foreign object is detected (No in step S9), the power transmission control unit 106 determines whether a predetermined duration has elapsed (step S10).

The power transmission control unit 106 receives the result of foreign matter detection at predetermined time intervals until the continuation time elapses, and when the continuation time elapses without detection of foreign matter (Yes in step S10), the foreign matter detection before power transmission ends A signal is transmitted to the foreign object detection unit 105 (step S11), and a transition to the power transmittable state M4 is made. When the foreign object detection unit 105 receives the foreign object detection completion signal before power transmission, the foreign object detection unit 105 ends the foreign object detection processing before power transmission (step S12).

In FIG. 11, the timing of the end of the pre-transmission foreign object detection state M2, that is, the timing of the end of the pre-transmission foreign object detection process by the foreign object detection unit 105 is limited by a predetermined duration. It may be limited by the number of foreign object detection (the number of transmission of detection results).

FIG. 12 is a flowchart showing a specific example of the operation of the power transmission and reception system until the power transmission control unit 106 transitions from the power transmission possible state M4 to the power transmission impossible state M3 or the power transmission state M5. In the power transmittable state M4, as described above, the foreign object detection processing before power transmission by the foreign object detection unit 105 is completed. Further, in FIG. 12, it is assumed that the electric vehicle is parked in the parking space so as to be able to transmit power by the power transmission device 100.

When the traveling electric vehicle is parked in the parking space, the power receiving device 200 mounted on the electric vehicle transmits a parking signal to the power transmission control unit 106 (step S13). Details of the parking signal transmission process (step S13) by the power receiving device 200 will be described later.

When the power transmission control unit 106 receives a parking signal (step S14), first, it transmits a foreign object detection start signal during power transmission to the foreign object detection unit 105 (step S15). When receiving the foreign object detection start signal during power transmission, the foreign object detection unit 105 starts the foreign object detection processing during power transmission (step S16), and transmits the detection result to the power transmission control unit 106 (step S17). After transmitting the detection result, the foreign matter detection unit 105 stands by for a predetermined time (step S18), and transmits the detection result again to the power transmission control unit 109 (step S19). In other words, when the foreign object detection process during power transmission is started, the foreign object detection unit 105 transmits the detection result to the power transmission control unit 106 at predetermined time intervals.

The power transmission control unit 106 receives the detection result from the foreign matter detection unit 105 (step S20), and transitions to the power transmission impossible state M3 when the foreign matter is detected (Yes in step S21). On the other hand, when no foreign object is detected (No in step S21), the power transmission control unit 106 executes power transmission start processing that causes the power transmission unit 101 to start power transmission (step S22), and transitions to the power transmission state M5. That is, the power transmission apparatus 100 starts power transmission after confirming that no foreign object is present according to the detection result of the foreign object detection processing during power transmission. Therefore, even if a foreign object appears between the end of the foreign object detection process before power transmission and the start of the foreign object detection process during power transmission, it can be detected before the start of power transmission. Therefore, it is possible to prevent the decrease in the power transmission efficiency due to the foreign matter and safely perform the power transmission.

The power transmission control unit 106 receives the detection result of the foreign object detection unit 105 at predetermined time intervals after transition to the power transmission state M5 (step S23). When the foreign object is detected by the foreign object detection unit 105 (Yes in step S24), the power transmission control unit 106 executes power transmission stop processing for causing the power transmission unit 101 to stop the power transmission processing (step S25). Transition. On the other hand, when the foreign object is not detected by the foreign object detection unit 105 (No in step S24), the power transmission control unit 106 maintains the power transmission state M5 and continues the power transmission.

Here, the parking signal transmission process (step S13) by the power receiving device 200 will be described in detail. The power reception control unit 204 of the power reception device 200 acquires a control signal of the ECU 207 of the electric vehicle as needed. As shown in FIG. 13, when the power reception control unit 204 acquires a control signal for parking the shift lever from the ECU 207, it determines that the electric vehicle has stopped, that is, parked in the parking space, and outputs a parking signal. , And transmits a parking signal to the power transmission device 100 via the communication unit 205 (step S13). Further, as shown in FIG. 14, the power reception control unit 204 can also transmit a parking signal to the power transmission device 100 when acquiring a control signal for turning on the side brake from the ECU 207 (step S13). Furthermore, as shown in FIG. 15, the power reception control unit 204 can also transmit a parking signal to the power transmission device 100 when acquiring a control signal for turning off the ignition key from the ECU 207 (step S13). Besides, the power reception control unit 204 can also transmit a parking signal to the power transmission device 100 when acquiring a control signal for unlocking the door key from the ECU 207 or a control signal for turning on only the accessory of the ignition key.

Furthermore, a configuration in which a parking signal is acquired from devices other than the power receiving device 200 is also possible. For example, a power transmission start terminal for causing the power transmission apparatus 100 to start power transmission is provided in the vicinity of a parking space or in a parking lot, and the driver who parked the electric vehicle operates the power transmission start terminal. It can also be configured to be sent to The power transmission device 100 may perform the processing of step S15 and subsequent steps triggered by the parking signal received from the power transmission start terminal. The power transmission start terminal is connected to the power transmission apparatus 100 in a wired or wireless manner.

FIG. 16 is a flowchart showing an operation of the power transmission / reception system from transition to the standby state M1 after the power transmission control unit 106 transitions from the pre-transmission foreign object detection state M2 or the power transmission state M5 to the power transmission impossible state M3. .

As shown in FIG. 16, when the foreign object detection state before power transmission M2 (power transmission state M5) is changed to the power non-transferable state M4, the foreign object detection unit 105 continues the foreign object detection processing before power transmission (foreign object detection processing during power transmission) ing. Therefore, the foreign matter detection unit 105 transmits the detection result at predetermined time intervals (steps S26 and S27), and the power transmission control unit 106 receives the transmitted detection result (step S28), and the foreign matter is detected. (Yes in step S29), the power transmission impossible state M4 is maintained. On the other hand, when the foreign object is not detected (No in step S29), the power transmission control unit 106 transmits the foreign object detection end signal before power transmission (the foreign object detection end signal during power transmission) (step S30), and transitions to the standby state M1. . When the foreign object detection unit 105 receives the foreign object detection end signal before power transmission (foreign object detection completion signal during power transmission), the foreign object detection unit 105 ends the foreign object detection processing before power transmission (foreign object detection processing during power transmission) (step S31).

If the foreign object detection state before power transmission M2 transitions to the power non-transferable state M4, the power transmission control unit 106 may transition to the power transmission enabled state M4 after step S30. When the power transmission state M5 transitions to the power transmission impossible state M4, after step S29, the processing may transition to the power transmission state M5 without ending the foreign object detection processing during power transmission. The operation of the power transmission and reception system after transition to the power transmission state M5 will be described later.

When transitioning to the power transmission impossible state M4, the power transmission control unit 106 may transmit a foreign substance detection notification signal to notify the driver of the electric vehicle that a foreign substance has been detected, as shown in FIG. For example, the power transmission control unit 106 can transmit a foreign object detection notification signal to the power receiving device 200 via the communication unit 107 (step S32). When the power receiving apparatus 200 receives the foreign substance detection notification signal via the communication unit 205 (step S33), the power receiving apparatus 200 notifies the driver that the foreign substance is detected (step S34). For example, the power receiving device 200 can display, via the ECU 207, an operation terminal of a car navigation system mounted on an electric vehicle that a foreign object has been detected. Notification to the driver may be performed by voice.

Also, a foreign matter detection and notification terminal other than the power reception device 200 may be provided. For example, the foreign matter detection notification terminal may be provided near the parking space, and the foreign matter detection notification signal may be transmitted to the foreign matter detection notification terminal. The foreign substance detection notification terminal that has received the foreign substance detection notification signal notifies the driver that the foreign substance has been detected by an image or a voice. As the foreign matter detection and notification terminal, an information terminal such as a mobile phone or a smartphone of a driver, or in the case of an electric vehicle, a key or an operation terminal of a car navigation system may be used.

Furthermore, the power transmission and reception system may include foreign matter removal notification means for notifying the power transmission device 100 that the driver has removed the foreign matter. In this case, in the power transmission impossible state M4, it is possible to set a predetermined duration for continuing the foreign matter detection processing. As shown in FIG. 18, the power transmission control unit 106 determines whether the continuation time of the foreign matter detection processing has elapsed (step S35), and when the continuation time has elapsed, transmits the foreign matter detection end signal before power transmission (during power transmission). (Step S36) The foreign object detection unit 105 that receives the foreign object detection end signal before power transmission (during power transmission) ends the foreign object detection processing before power transmission (during power transmission) (step S37). Thereafter, the power transmission control unit 106 stands by until the foreign matter removal notification signal for notifying that the driver has removed the foreign matter is received from the foreign matter removal notification means (step S38).

When the power transmission control unit 106 receives the foreign matter removal notification signal (Yes in step S38), it transmits a foreign matter detection start signal (step S39), and the foreign matter detection unit 105 that receives the foreign matter detection start signal executes foreign matter detection ( Step S40). The power transmission control unit 105 receives the detection result from the foreign matter detection unit 105 (steps S41 and S42), and when no foreign matter is detected (No in step S43), transitions to the standby state M1. On the other hand, when the foreign object is detected (No in step S43), the power transmission control unit 106 transmits the foreign object detection notification signal again (step S32).

The foreign matter removal notification means may be a terminal provided near the parking space, or may be a mobile phone of a driver. A foreign object detection and removal signal may be transmitted from the operation terminal of the car navigation system mounted on the electric vehicle via the power receiving device 200. With such a configuration, when foreign matter is not removed forever, the foreign matter detection unit 105 can be prevented from continuing to execute the foreign matter detection processing, and power consumption of the power transmission device 100 can be reduced.

FIG. 19 is a flowchart showing an operation of the power transmission and reception system until the power transmission control unit 106 transitions from the power transmission state M4 to the standby state M1. In the power transmission state M4, the foreign object detection processing during power transmission is executed, and when a foreign object is detected, the power transmission control unit 106 transitions to the power transmission impossible state M3. Such an operation is as described in FIG. 12, and thus the description thereof is omitted in FIG.

As shown in FIG. 19, in the power transmission state M4, the ECU 207 of the electric vehicle confirms the charge state of the battery (step S44), and determines whether the charge amount is equal to or more than the full charge threshold (step S45). If the battery is fully charged (Yes in step S45), the power reception control unit 204 acquires a control signal indicating that the battery is fully charged from the ECU 207, and the power transmission control unit 106 via the communication unit 206. The power transmission stop signal is transmitted to (step S46). When the function of the power reception control unit 204 is realized by the ECU 207, the ECU 207 transmits a power transmission stop signal. Further, the power reception control unit 204 may determine whether or not the battery is fully charged.

When the power transmission control unit 106 receives the power transmission stop signal (step S47), the power transmission control unit 106 executes power transmission end processing for causing the power transmission unit 101 to end power transmission (step S48). When the power transmission ends, the power transmission control unit 106 transmits a power transmission end signal to the power reception control unit 204 (step S49), and transitions to the standby state M1. The power reception control unit 204 receives the power transmission end signal (step S50), and charging of the battery is completed. Such operation of the power transmission and reception system can prevent overcharging of the battery of the electric vehicle.

Further, as shown in FIG. 20, it is also possible to end power transmission in accordance with the departure of the electric vehicle. When receiving a signal to turn on the ignition key from the ECU of the electric vehicle (step S51), the power reception control unit 204 determines the departure of the electric vehicle and transmits a power transmission stop signal to the power transmission control unit 106 (step S46). The following operation is similar to that of FIG. 19 and steps S47 to S50. The power reception control unit 204 determines the departure of the electric vehicle based on a control signal to turn off the side brake, a control signal to turn on the shift lever for driving or the like, a signal to unlock the door key, etc. You can also.

As described above, according to the present embodiment, foreign object detection processing before power transmission is performed before the power transmission object enters the erroneous detection range, that is, when the power transmission object enters the first detection range. The possibility of false detection is suppressed. Moreover, since foreign object detection is performed before and during power transmission and power transmission is performed after power transmission is performed after it is confirmed that foreign objects are not detected, power transmission efficiency can be prevented safely and safely.

Second Embodiment
Hereinafter, the power transmission and reception system according to the second embodiment will be described with reference to FIGS. 21 and 22. The configurations of the power transmission device 100 and the power reception device 200 in the present embodiment are the same as in the first embodiment.

Here, FIG. 21 is a transition diagram illustrating an example of the transition of the operation state of the power transmission control unit 106 according to the present embodiment. As shown in FIG. 21, in the present embodiment, the power transmission control unit 106 has a power transmission object authentication state M6 in which an authentication process is performed on the power transmission object detected by the first power transmission object detection unit 104.

In the standby state M1, when the power transmission target is detected by the first power transmission target detection unit 104, the operation state of the power transmission control unit 106 transitions to the power transmission target recognition state M6. In the power transmission target recognition state M6, the power transmission target unit 104 (power transmission target authentication unit) determines whether the power transmission target is a power transmission target that can be transmitted by the power transmission unit 101. If the power transmission control unit 106 determines that power transmission to the detected power transmission target is possible (if authentication is successful), the power transmission control unit 106 transitions to the pre-power transmission foreign object detection state M2. On the other hand, when the power transmission control unit 106 determines that power transmission to the detected power transmission target is impossible, the power transmission control unit 106 transitions to the standby state M1.

The case where the power transmission target detected by the first power transmission target detection unit 104 can not transmit power is, for example, the case of an electric vehicle of a power reception method different from the power transmission method of the power transmission unit 101. In addition, when the first power transmission target detection unit 104 detects a power transmission target using a weight sensor, it may be considered that a vehicle other than the electric vehicle (such as a gasoline car) is detected as the power transmission target. In the present embodiment, it is not necessary to execute various types of processing on a power transmission target that can not transmit power by determining in advance whether power transmission can be performed on power transmission targets, so the power consumption of the power transmission apparatus 100 can be reduced. it can.

FIG. 22 is a flowchart showing the operation of the power transmission and reception system until the operation state of the power transmission control unit 106 transitions from the standby state M1 to the foreign object detection state before power transmission M2. Steps S1 to S3 in FIG. 22 are the same as those in FIG. In addition, the operation of the power transmission and reception system after the foreign object detection state M2 before power transmission is the same as that of the above-described embodiment.

In the present embodiment, when the power transmission control unit 106 receives the power transmission target detection signal (step S3), the power transmission control unit 106 transitions to the power transmission target authentication state M6. In the power transmission target authentication state M6, the power transmission control unit 106 executes wireless connection processing with the power reception control unit 204 via the communication unit 107 (step S51). When the function of the power reception control unit 204 is realized by the ECU 207, the wireless connection process with the ECU 207 is executed. When the wireless connection is not established within a predetermined time (step S52), the power transmission control unit 106 determines that the power transmission target detected by the first power transmission target detection unit 104 can not transmit power, and transitions to the standby state M1. On the other hand, when the wireless connection is established within a predetermined time (Yes in step S52), the power transmission control unit 106 transmits a power transmission target authentication inquiry to the power reception control unit 204 (step S53). The power transmission control unit 106 requests authentication information for determining whether or not the power transmission target detected by the first power transmission target detection unit 104 can transmit power in the power transmission target authentication inquiry. The authentication information includes, for example, ID information of the power receiving device 200 and the electric vehicle.

If the power reception control unit 204 can not obtain a response from the power reception control unit 204 within a predetermined time (No in step S54), the power transmission control unit 106 transitions to the standby state M1. On the other hand, when the power transmission control unit 106 receives a response from the power reception control unit 204 within a predetermined time (Yes in step S54), that is, the power reception control unit 204 that has received the power transmission object authentication inquiry transmits authentication information. When the power transmission control unit 106 receives the authentication information (steps S55 to S57), the authentication process is performed (step S58). The power transmission control unit 106 determines whether power transmission is possible based on the received authentication information, and when it is determined that power transmission is not possible (authentication failure) (No in step S58), transits to the standby state M1 and power transmission is possible (authentication When it is determined that the process is successful (Yes in step S58), the state is switched to the foreign object detection state M2 before power transmission.

The power reception control unit 204 may acquire the authentication information from the ECU 207 in step S56. In addition, the power reception control unit 204 may include an authentication information storage unit storing authentication information, and may transmit the authentication information acquired from the authentication information storage unit to the power transmission control unit 106. The power reception control unit 204 transmits the acquired authentication information to the power transmission control unit 106 via the communication unit 205.

As described above, according to the present embodiment, various types of power transmission can not be performed by determining in advance (authentication) whether the power transmission target detected by the first power transmission target detection unit 104 can actually transmit power. The power consumption of the power transmission and reception system can be reduced because it is not necessary to execute the processing (for example, foreign substance detection processing) of the above.

Third Embodiment
The power transmission and reception system according to the third embodiment will be described below with reference to FIGS. 23 and 24. In the present embodiment, the foreign object detection unit 105 ends the foreign object detection process before power transmission when the power transmission target enters the second detection range. Here, FIG. 23 is a block diagram showing a configuration of the power transmission device 100 according to the present embodiment. As shown in FIG. 23, the power transmission device 100 includes a power transmission unit 101, a first power transmission target detection unit 104, a foreign object detection unit 105, a power transmission control unit 106, and a communication unit 107. The above configuration is the same as that of the above embodiment. In the present embodiment, the power transmission device 100 further includes a second power transmission target detection unit 108.

The second power transmission target detection unit 108 detects that the power transmission target has entered the second detection range. The second detection range is a range predetermined to detect that the power transmission target approaches the false detection range, and is set to include the false detection range. Further, the second detection range is set to be included in the first detection range, that is, set narrower than the first detection range. The second detection range may coincide with the false detection range. The foreign object detection unit 105 ends the foreign object detection process before power transmission at the timing when the power transmission target enters the second detection range.

In order to detect that the power transmission target has entered the second detection range, the second power transmission target detection unit 108 can detect the power transmission target in part or all of the periphery of the second detection range, One or more are provided. When the approach direction of the power transmission target is determined in advance, one second power transmission target detection unit 108 may be installed in the approach direction of the second detection range. As the second power transmission target detection unit 108, various detection means such as an infrared sensor, an ultrasonic sensor, and a weight sensor can be used, for example. Further, as in the case of the first power transmission target detection unit 104, it can be realized using the communication unit 107. Furthermore, the configuration of the second power transmission target detection unit 108 may be the same as or different from that of the first power transmission target detection unit 104. Also, the functions of the first power transmission target detection unit 104 and the second power transmission target detection unit 108 may be realized by a single power transmission target detection unit. The configuration of the second power transmission target detection unit 108 is not limited to these, and may be any configuration that can detect that the power transmission target has entered the second detection range.

FIG. 24 is a flowchart showing an operation of the power transmission and reception system until the power transmission control unit 106 transitions from the pre-power transmission foreign object detection state M2 to the power non-transmission possible state M3 or the power transmission possible state M4. The operation up to the foreign object detection state M2 before power transmission and the operations after the power non-permission state M3 and the power transmission possible state M4 are the same as those in the above-described embodiment.

In the foreign object detection state before power transmission M2, the power transmission control unit 106 transmits a power transmission target detection start signal to the second power transmission target detection unit 108 (step S59). When the power transmission target detection start signal is received, the second power transmission target detection unit 108 starts power transmission target detection processing (step S60). That is, the second power transmission target detection unit 108 does not operate until the power transmission control unit 106 transitions to the foreign object detection state M2 before power transmission. Thereby, the power consumption of the power transmission and reception system can be reduced.

The second power transmission target detection unit 108 executes detection processing at predetermined time intervals, and transmits the detection result to the power transmission control unit 106 (steps S61 and S62). Further, the power transmission control unit 106 causes the foreign object detection unit 105 to start the foreign object detection processing before power transmission (steps S4 to S7). The foreign object detection processing before power transmission by the foreign object detection unit 105 is the same as that of the above-described embodiment.

The power transmission control unit 106 receives the detection result from the second power transmission target detection unit 108 at predetermined time intervals (step S63). When the power transmission target has not entered the second detection range (No in step S64), the power transmission control unit 106 receives the detection result from the foreign object detection unit 105 (step S8). When the foreign object is detected (Yes in step S9), the power transmission control unit 106 transitions to the power transmission impossible state, and when the foreign object is not detected (step S9), the detection result of the second power transmission object detection unit 108 It receives again (step S63).

On the other hand, when the power transmission target enters the second detection range (Yes at step S64), the power transmission control unit 106 ends the foreign object detection processing before power transmission by the foreign object detection unit 105 (steps S11 and S12). The power transmission target detection process by the target detection unit 108 is ended (steps S65 and S66), and the state is transitioned to the power transmittable state M4.

As described above, the foreign object detection unit 105 starts the foreign object detection processing before power transmission when the power transmission target enters the first detection range, and ends the foreign object detection processing before power transmission when the power transmission target enters the second detection range. . The second detection range is set to include the erroneous detection range, so that the possibility that the power transmission target is erroneously detected as a foreign object by the foreign object detection unit 105 can be more reliably reduced.

Fourth Embodiment
The power transmission and reception system according to the fourth embodiment will be described below with reference to FIGS. 25 and 26. Here, FIG. 25 is a block diagram showing a configuration of the power transmission device 100 according to the present embodiment. As shown in FIG. 25, in the present embodiment, the second power transmission target detection unit 108 includes a position detection unit 109 and a power transmission control unit 106. The other configuration is the same as that of the third embodiment.

The position detection unit 109 detects the relative position (relative distance) of the power transmission target with respect to the position detection unit 109 and the power transmission coil 103. As the position detection unit 109, for example, alignment means can be used. The alignment means is a means for aligning the power transmission coil 103 and the power reception coil 202, and is configured of a sensor or the like capable of detecting a position within several meters. The alignment means includes, for example, proximity wireless such as RFID and NFC, an ultrasonic sensor, a CMOS sensor, and the like. By using the alignment unit as the position detection unit 109, a new sensor or the like for configuring the second power transmission object detection unit 108 becomes unnecessary, and the configuration of the second power transmission object detection unit 108 can be simplified. .

The power transmission control unit 106 detects that the power transmission target has entered the second detection range by comparing the relative position of the power transmission target detected by the position detection unit 109 with the second detection range. That is, the function of the second power transmission target detection unit 108 in the third embodiment is realized by the position detection unit 109 and the power transmission control unit 106.

FIG. 26 is a flowchart showing a specific example of the operation of the power transmission and reception system until the power transmission control unit 106 transitions from the pre-power transmission foreign object detection state M2 to the power non-transmission possible state M3 or the power transmission possible state M4. The operation up to the foreign object detection state M2 before power transmission and the operations after the power non-permission state M3 and the power transmission possible state M4 are the same as those in the above-described embodiment.

In the foreign object detection state M2 before power transmission, the power transmission control unit 106 transmits a position detection start signal to the position detection unit 109 (step S67). When the position detection unit 109 receives the position detection start signal, the position detection unit 109 starts position detection processing (step S68). That is, the position detection unit 109 does not operate until the power transmission control unit 106 transitions to the pre-power transmission foreign object detection state M2. Thereby, the power consumption of the power transmission and reception system can be reduced.

The position detection unit 109 executes position detection processing at predetermined time intervals, and transmits the detection result to the power transmission control unit 106 (steps S69 and S70). Further, the power transmission control unit 106 causes the foreign object detection unit 105 to start the foreign object detection processing before power transmission (steps S4 to S7). The foreign object detection processing before power transmission by the foreign object detection unit 105 is the same as that of the above-described embodiment.

The power transmission control unit 106 receives the detection result from the position detection unit 109 at predetermined time intervals (step S71), and the received detection result, that is, the relative position of the power transmission target and the second detection range set in advance Are compared, and it is determined whether the power transmission target has entered the second detection range (step S72). The determination can be performed, for example, by comparing the relative distance from the position detection unit 109 or the power transmission coil 103 set as the second relative distance with the relative distance of the detected power transmission target.

When it is determined that the power transmission target has not entered the second detection range (No in step S72), the power transmission control unit 106 receives the detection result from the foreign object detection unit 105 (step S8). When the foreign object is detected (Yes in step S9), the power transmission control unit 106 transitions to the power transmission impossible state, and when the foreign object is not detected (step S9), the detection result of the second power transmission object detection unit 108 It receives (step S71).

On the other hand, when the power transmission control unit 106 determines that the power transmission target has entered the second detection range (Yes in step S72), the foreign object detection unit 105 ends the pre-power transmission foreign object detection processing (steps S11 and S12), The position detection process by the position detection unit 109 is ended (steps S73 and S74), and the state is transitioned to the power transmittable state M4. When the above-mentioned alignment means is used as the position detection unit 109, it is preferable to omit steps S73 and S74 in FIG. 26 and continue the position detection process.

Fifth Embodiment
The power transmission and reception system according to the fifth embodiment will be described below with reference to FIG. In the present embodiment, the configuration of the power transmission and reception system is the same as that of the fourth embodiment. However, in the present embodiment, the power transmission control unit 106 determines whether the power transmission target has entered the third detection range, and the foreign object detection unit 105 detects foreign objects after the power transmission target has entered the third detection range. Execute the process

Here, FIG. 27 is a flowchart illustrating a specific example of the operation of the power transmission and reception system until the power transmission control unit 106 transitions from the pre-power transmission foreign object detection state M2 to the power non-transferable state M3 or the power transmittable state M4. The operation up to the foreign object detection state M2 before power transmission and the operations after the power non-permission state M3 and the power transmission possible state M4 are the same as those in the above-described embodiment. Further, in the present embodiment, the operation (steps S67 to S71) from the transition of the power transmission control unit 106 to the foreign object detection state before power transmission to the reception of the detection result (steps S67 to S71) is similar to that of the fourth embodiment.

When the power transmission control unit 106 receives the detection result (step S71), the power transmission control unit 106 determines whether the power transmission target has entered the third detection range (step S75). The third detection range is a range that includes the false detection range and is included in the first detection range, and is set by adding a predetermined offset distance to the false detection range.

The offset distance is preferably a few cm to 1 m or less. In particular, the offset distance is the moving speed v (m / s) of the power transmission target, and the delay time t (s) from when the power transmission control unit 106 causes the foreign object detection unit 105 to start the foreign object detection processing until the detection result is received. It is preferable that the offset distance v v (m / s) x t (s).

The moving speed of the power transmission target is provided with a timer in the position detection unit 109, and the difference of the relative position of the power transmission target when position detection is performed twice or more is divided by the position detection interval (predetermined time in step S70). It can be calculated by When the power transmission target includes the speed measurement device, the power transmission device 100 may acquire the moving speed of the power transmission target from the speed measurement device via the power reception device 200.

If the power transmission control unit 106 determines that the power transmission target has entered the third detection range (Yes in step S75), the power transmission control unit 106 transmits a foreign object detection start signal before power transmission to the foreign object detection unit 105 (step S4). When the foreign object detection unit 105 receives the foreign object detection start signal before power transmission (step S5), the foreign object detection unit 105 performs foreign object detection a predetermined number of times, transmits the detection result (step S6), and ends the foreign object detection process before power transmission ( Step S12). The number of times the foreign object detection unit 105 executes foreign object detection is determined according to the offset distance, and the foreign object detection process before power transmission is determined to end before the power transmission target enters the erroneous detection range. For example, in the case of offset distance = v (m / s) × t (s), the object to be transmitted does not enter at least the erroneous detection range within the delay time until the foreign matter detection result is received once. Detection is performed only once. When a foreign object is detected, the power transmission control unit 106 transitions to the power transmission impossible state M3. When no foreign object is detected, the power transmission control unit 106 ends the position detection process and the foreign object detection process, and transitions to the power transmittable state M4.

As described above, according to the present embodiment, the foreign object detection processing before power transmission starts when the power transmission target enters the third detection range, and ends before entering the erroneous detection range. Therefore, the process can be simplified as compared with the fourth embodiment in which the determination as to whether or not the power transmission target has entered the second detection range and the foreign object detection process are simultaneously performed.

In the present embodiment, the power transmission control unit 106 may end the position detection process when it is determined that the power transmission target has entered the third detection range.

Sixth Embodiment
The power transmission and reception system according to the sixth embodiment will be described below with reference to FIGS. 28 and 29. Here, FIG. 28 is a block diagram showing a configuration of the power transmission device 100 according to the present embodiment. As shown in FIG. 28, in the present embodiment, the first power transmission target detection unit 104 and the second power transmission target detection unit 108 are both configured by the position detection unit 109 and the power transmission control unit 106. In addition, the other structure is the same as that of the above-mentioned embodiment.

FIG. 29 is a flowchart showing an operation of the power transmission and reception system until the power transmission control unit 106 transitions from the standby state M1 to the foreign object detection state M2 before power transmission. As shown in FIG. 29, the position detection unit 109 always executes position detection processing (steps S76 and S77), and the power transmission control unit 106 receives detection results from the position detection unit 109 at predetermined time intervals. (Step S78). When the position detection of the power transmission target is possible (Yes at step S79), the power transmission control unit 106 determines that the power transmission target has entered the first detection range (step S80), and sets the foreign object detection state before power transmission M2. Transition. That is, in the present embodiment, the first detection range is a detectable range of the position detection unit 109. The subsequent operation is the same as that of the fifth embodiment.

As described above, in the present embodiment, the position detection unit 109 and the power transmission control unit 106 constitute a first power transmission object detection unit 104 and a second power transmission object detection unit 108. Therefore, the configuration of power transmission device 100 can be simplified.

In the present embodiment, the first detection range may be set by the relative position from the position detection unit 109. In this case, the power transmission control unit 106 has entered the first detection range by comparing the relative position of the power transmission target detected by the position detection unit 109 with the first detection range set in advance. It can be determined whether or not. In addition, it is possible to determine whether the power transmission target has entered the second detection range or the third detection range by the second power transmission target detection unit 108 configured by the position detection unit 109 and the power transmission control unit 106. It is.

Seventh Embodiment
The power transmission and reception system according to the seventh embodiment will be described below with reference to FIGS. 30 and 31. Here, FIG. 30 is a block diagram showing a configuration of a power transmission and reception system according to the present embodiment. As shown in FIG. 30, in the present embodiment, the second power transmission target detection unit 108 is provided in the power receiving device 200. When detecting that the power transmission target has entered the second detection range, the second power transmission target detection unit 108 notifies the power transmission control unit 106 via the communication unit 205. In addition, the other structure is the same as that of the above-mentioned embodiment.

FIG. 31 is a flowchart showing an operation of the power transmission and reception system until the power transmission control unit 106 transitions from the pre-power transmission foreign object detection state M2 to the power non-transmission possible state M3 or the power transmission possible state M4. As shown in FIG. 31, the power transmission control unit 106 causes the second power transmission object detection unit 108 provided in the power receiving device 200 to start power transmission object detection processing in the foreign object detection state before power transmission 200 and detects at predetermined time intervals. The result is received (steps S59 to S63). The subsequent operation is the same as that of FIG.

In order to enable such an operation, the power transmission control unit 106 establishes communication with the power receiving device 200 in advance via the communication unit 107. For example, as described in FIG. 22, communication may be established by performing authentication processing between the power transmission control unit 106 and the power receiving apparatus 200. Also, at the time of transition to the foreign object detection state M2 before power transmission, communication between the power transmission control unit 106 and the power receiving device 200 may be established.

In the present embodiment, the second power transmission target detection unit 108 is provided in the power reception device 200, but the first power transmission target detection object 104 may be provided in the power reception device 200, or the first power transmission target detection unit and the second Both of the power transmission target detection units 108 may be provided in the power receiving apparatus 200.

Further, instead of the second power transmission target detection unit 108, the position detection unit 109 may be provided in the power reception device 200. In this case, at least one of the first power transmission object detection unit 104 and the second power transmission object detection unit 108 is configured by the position detection unit 109 provided in the power reception device 200 and the power transmission control unit 106 provided in the power transmission device 100. May be That is, based on the relative position information of the power transmission target received from the position detection unit 109 provided in the power reception device 200, the power transmission control unit 106 has entered the first detection range (second detection range). May be detected.

Furthermore, at least one of the first power transmission object detection unit 104 and the second power transmission object detection unit 108 may be configured by the position detection unit 109 and the power reception control unit 204 provided in the power reception device 200. In this case, the power reception control unit 204 detects that the power transmission target has entered the first detection range (second detection range) based on the relative position information of the power transmission target detected by the position detection unit 109, and transmits power. The detection signal may be transmitted to the power transmission control unit 106.

The present invention is not limited to the above embodiments as it is, and at the implementation stage, the constituent elements can be modified and embodied without departing from the scope of the invention. In addition, various inventions can be formed by appropriately combining the plurality of components disclosed in the above-described embodiments. Further, for example, a configuration in which some components are removed from all the components shown in each embodiment is also conceivable. Furthermore, the components described in different embodiments may be combined as appropriate.

100: power transmission device, 101: power transmission unit, 102: power transmission circuit, 103: power transmission coil, 104: first power transmission object detection unit, 105: foreign object detection unit, 106: power transmission control unit, 107: communication unit, 108: second Power transmission object detection unit 109: position detection unit 110: power supply 200: power reception device 201: power reception unit 202: power reception coil 203: power reception circuit 204: power reception control unit 205: communication unit 206: load

Claims

A power transmission unit that transmits power without contact to the power transmission target;
A power transmission target detection unit that detects that the power transmission target has entered a predetermined detection range including the power transmission unit;
In the detection range, a foreign matter detection unit that detects foreign matter that impedes power transmission by the power transmission unit;
Equipped with
The non-contact power transmission device, wherein the foreign matter detection unit starts or ends detection of a foreign matter based on a detection result by the power transmission target detection unit.
The power transmission target detection unit includes a first power transmission target detection unit that detects that the power transmission target has entered a first detection range.
The non-contact power transmission device according to claim 1, wherein the foreign matter detection unit starts the detection of a foreign matter when the first power transmission object detection unit detects that the power transmission object has entered the first detection range.
3. The foreign matter detection unit according to claim 1, wherein the foreign matter detection unit terminates the detection of the foreign matter before the power transmission target enters an erroneous detection range preset as a range in which the power transmission target may be erroneously detected as the foreign matter. Contactless power transmission device as described.
The power transmission target detection unit includes a second power transmission target detection unit that detects that the power transmission target has entered the second detection range,
The foreign matter detection unit according to claim 2 or 3, wherein the foreign matter detection unit terminates the detection of the foreign matter when the second power transmission object detection unit detects that the power transmission object has entered the second detection range. Contact power transmission device.
The non-contact power transmission device according to claim 3, wherein the first detection range includes the false detection range.
The non-contact power transmission device according to claim 4 or 5, wherein the second detection range includes the false detection range.
The non-contact power transmission device according to any one of claims 4 to 6, wherein the first detection range includes the second detection range.
The non-contact power transmission device according to any one of claims 3 to 7, wherein the erroneous detection range is set according to the relative position from the foreign matter detection unit.
The erroneous detection range is set according to the relative position of the power transmission target when the power transmission target is erroneously detected as a foreign substance by the foreign substance detection unit. Contactless power transmission device.
The non-contact power transmission device according to any one of claims 1 to 9, wherein the foreign matter detection unit performs foreign matter detection during power transmission to the power transmission target by the power transmission unit.
The non-contact power transmission device according to any one of claims 1 to 10, further comprising: a foreign matter detection and notification means for notifying that the foreign matter is detected by the foreign matter detection unit.
The non-contact power transmission device according to claim 10, wherein the foreign matter detection unit detects foreign matter using different methods or parameters for foreign matter detection before power transmission start and foreign matter detection during power transmission.
The power transmission target authentication unit according to any one of claims 1 to 12, further comprising: a power transmission target authentication unit that determines whether the power transmission target detected by the power transmission target detection unit is a power transmission target that can transmit power by the power transmission unit. Contactless power transmission device.
The power transmission target detection unit includes a position detection unit that detects the relative position of the power transmission target, and the power transmission target enters the detection range based on the relative position information of the power transmission target detected by the position detection unit. The non-contact power transmission device according to any one of claims 1 to 13, which detects an event.
The second power transmission target detection unit according to any one of claims 4 to 14, wherein when the power transmission target is detected by the first power transmission target detection unit, detection of the power transmission target is started. Contact power transmission device.
The non-contact power transmission device according to any one of claims 1 to 15, wherein the power transmission unit transmits power by a magnetic field resonance method, an electromagnetic induction method, or a radio wave method.
The non-contact power transmission device according to any one of claims 1 to 16, further comprising a communication unit that enables wireless communication with an external device.
It is mounted on a power transmission target that transmits power without contact.
A power receiving unit that receives power without contact;
A power reception control unit that acquires information on the power transmission target;
A communication unit that enables communication with an external device;
Non-contact power receiving device comprising
The power reception control unit acquires, from the control unit of the power transmission target, information indicating that the power transmission target has stopped,
The non-contact power receiving device according to claim 18, wherein a stop signal notifying that the power transmission target has stopped is transmitted to the external device via the communication unit based on the information.
The non-contact power reception device according to claim 18, wherein the power reception unit charges the received power to a battery included in the power transmission target.
The non-contact according to any one of claims 18 to 20, wherein the power reception control unit transmits authentication information indicating that the power transmission target can receive power without contact via the communication unit to an external device. Power receiving device.
The non-contact power receiving device according to any one of claims 18 to 21, wherein the information on the power transmission target includes information indicating a moving speed of the power transmission target.
It further comprises a power transmission object detection unit that detects that the power transmission object has entered into a predetermined detection range,
The non-contact power receiving device according to any one of claims 18 to 22, wherein the power reception control unit notifies an external device that the power transmission target has entered the detection range via the communication unit.
A power transmission unit for transmitting power without contact to the power transmission target; a power transmission target detection unit for detecting that the power transmission target has entered a predetermined detection range including the power transmission unit; and the power transmission within the detection range And a non-contact power transmission device for starting or ending detection of a foreign object based on a detection result by the power transmission target detection unit.
A non-contact power receiving device comprising: a power receiving unit mounted on the power transmission target and receiving power without contact; a power reception control unit acquiring information on the power transmission target; and a communication unit enabling communication with an external device ,
Contactless power transmission and reception system comprising