JP6527624B2 - Power transmission device, power transmission control method, and program - Google Patents

Description

  The present invention relates to a power transmission device, a power transmission control method, and a program related to wireless power transmission.

  At present, various methods for performing wireless power transmission, such as an electromagnetic induction method and a magnetic field resonance method, are known. Also, there are a plurality of standards for securing the interconnectivity of the power transmission device and the power reception device in the wireless power transmission system. Non-Patent Document 1 describes an IC chip that supports a plurality of standards for wireless power transmission.

http://en.idt.com/about/press-room/idt-announces-industry%E2%80%99s-first-dual-mode-wireless-power-receiver-ic-compatible-both-wpc-and- pma-stan

  In a system in which a plurality of wireless power transmission schemes (WPT schemes) are supported, depending on the wireless power transmission scheme used for power transmission, the efficiency of wireless power transmission may be degraded. For example, the case where the power transmission apparatus supports the first WPT method (the upper limit of transmission power is 5 W) and the second WPT method (the upper limit of transmission power is 10 W) will be described. At this time, when power transmission of 5 W is performed by the first WPT method to the power receiving device (supporting the first and second WPT methods) initially placed on the charging stand in the power transmitting device, the power receiving device is During the power transmission in the above, there is a risk that a power receiving device that supports only the first WPT method can not be charged. Further, for example, in the above case, the efficiency is low if only 5 W can receive power although the power receiving device initially placed on the charging stand can receive 10 W of power supply.

  The present invention has been made to solve the above-mentioned problems, and its object is to improve the efficiency of wireless power transmission in a system in which multiple wireless power transmission schemes are supported.

  In order to solve the above problems, the power transmission device of the present invention has the following configuration. That is, the power transmission apparatus wirelessly transmits power, and the power receiving apparatus detects a power receiving apparatus, and the negotiation for determining a parameter for power transmission wirelessly to the power receiving apparatus detected by the detection section is the power receiving Among the plurality of wireless power transmission methods which are performed between the device and the plurality of wireless power transmission methods having different transmittable power amounts, the wireless power transmission method supported by the power receiving device detected by the detecting portion is performed before the negotiation by the negotiation portion Specific to the power receiving device based on the parameter determined in the negotiation performed with the power receiving device by the negotiation device in accordance with the wireless power transmission method specified by the specifying device, and Power transmission means for wirelessly transmitting power.

  According to the present invention, it is possible to improve the efficiency of wireless power transfer in a system in which a plurality of wireless power transfer schemes are supported.

The conceptual diagram of embodiment. FIG. 2 is a block diagram showing an example of the functional configuration of the power transmission device 101 and the power reception device 103 according to the embodiment. FIG. 7 is a sequence diagram for explaining the operations of the power transmission device 101 and the power reception device 103 according to the first embodiment. 6 is a flowchart for explaining the operation of the power transmission device 101 according to the first embodiment. 6 is a flowchart for explaining the operation of the power receiving device 103 of the first embodiment. The sequence diagram for demonstrating operation | movement of the power transmission apparatus 101 of 2nd Embodiment, and the power receiving apparatus 103. FIG. 7 is a flowchart for explaining the operation of the power transmission device 101 of the second embodiment. 9 is a flowchart for explaining the operation of the power receiving device 103 of the second embodiment. The flowchart for demonstrating the determination processing of whether to change WPT system.

  Hereinafter, the present invention will be described in detail based on preferred embodiments thereof with reference to the attached drawings. In addition, the structure shown in the following embodiment is only an example, and this invention is not limited to the illustrated structure.

First Embodiment
FIG. 1 is a conceptual diagram for explaining an example of a usage scene of the present embodiment. As shown in FIG. 1, a plurality of power reception devices 103 (power reception devices 103-1 and 103-2) exist in the power transmission range 102 of the power transmission device 101. Note that the power transmission device 101 can be incorporated into an electrical product such as a notebook PC, a DVD recorder, or a video deck, or furniture such as a table, a desk, or a television stand. Although FIG. 1 illustrates an example in which the power receiving device 103 is a digital camera or a smartphone, the present invention may be applied to various electric products such as a video camera, a notebook PC, and a feature phone, for example. It is possible. The power reception device 103 is a power reception device capable of receiving the power wirelessly transmitted from the power transmission device 101. The power receiving device 103 can charge the battery and drive the device using received power.

表１において、第１のＷＰＴ方式としての電力伝送の制御用通信方式は負荷変調であり、第２のＷＰＴ方式としての電力伝送の制御用通信方式はBluetooth(登録商標)であり、第３のＷＰＴ方式としての電力伝送の制御用通信方式はIEEE802.11nである。IEEE802.11及びBluetooth(登録商標)の通信可能距離は負荷変調の通信可能距離よりも長い。 In the present embodiment, an example in which the power transmission apparatus 101 supports three wireless power transmission methods (WPT methods) shown in Table 1 will be described. However, the present invention is not limited to this example, and the power transmission apparatus 101 can support a plurality of WPT methods. Further, in the present embodiment, an example will be described in which the power transmission apparatus 101 determines which WPT method is used to transmit power among the three WPT methods supported by the power transmission apparatus 101.

In Table 1, the communication method for controlling power transmission as the first WPT method is load modulation, the communication method for controlling power transmission as the second WPT method is Bluetooth (registered trademark), and the third method is used. The communication system for controlling power transmission as the WPT system is IEEE 802.11n. The communicable distance of IEEE 802.11 and Bluetooth (registered trademark) is longer than the communicable distance of load modulation.

  Although FIG. 1 illustrates an example in which two power receiving devices 103 exist within the power transmission range, three or more power receiving devices 103 may be disposed in the power transmission range 102. The power transmission device 101 according to the present embodiment can perform wireless power transmission to a plurality of power reception devices 103 present in a power transmission range.

  Next, configurations of the power transmission device 101 and the power reception device 103 in the present embodiment will be described with reference to FIG. FIG. 2 is a block diagram for explaining functional configurations of the power transmission device 101 and the power reception device 103. The power transmission apparatus 101 includes a power transmission control unit 201, a UI (user interface) 202, a storage unit 203, a communication control unit 204, a plurality of power transmission units 205, a plurality of power transmission antennas 206, a communication unit 207, a communication antenna 208, and a detection unit 209. Configured to include. In the present embodiment, different power transmission units 205 and power transmission antennas 206 exist for each WPT method, but the power transmission units 205 and the power transmission antennas 206 may be shared by a plurality of WPT methods.

  Among the plurality of wireless power transmission methods (WPT methods) supported by the power transmission device 101, the power transmission control unit 201 determines which WPT method is used to transmit power to the power receiving device 103 within the power transmission range. The outline of the WPT method supported by the power transmission device 101 of the present embodiment is as shown in Table 1 above. In addition, the power transmission control unit 201 receives the power transmission to the power receiving apparatus 103-1, and then detects a power receiving apparatus 103-1 according to the WPT method supported by the power receiving apparatus 103-N newly detected by the detection unit 209. Change the WPT method used for power transfer to That is, the power transmission control unit 201 can switch between the first wireless power transmission method and the second wireless power transmission method. The method of determining the WPT method by the power transmission control unit 201 and the method of changing the WPT method will be described later.

  The UI 202 is an interface for the user to perform various settings on the power transmission apparatus 101. The storage unit 203 stores, for example, various types of information used by the power transmission control unit 201 for determining the WPT method and changing the WPT method. The information stored in the storage unit 203 will be described later. The communication control unit 204 controls the communication unit 207 to realize communication with the power receiving apparatus 103. The communication unit 207 implements communication with the power receiving apparatus 103 via the communication antenna 208 according to the control from the communication control unit 204. In the present embodiment, it is possible to perform communication regarding various control for wireless power transmission using the communication unit 207. A communicable range (communication range) by the communication unit 207 is wider than the power transmission range 102.

  The power transmission unit 205 controls various parameters such as a current value and a voltage value applied to the power transmission antenna 206 based on the control from the power transmission control unit 201, and implements wireless power transmission to the power receiving device 103. Note that the power transmission device 101 of the present embodiment includes the same number of power transmission units 205 and power transmission antennas 206 as the number of WPT methods supported. The detection unit 209 detects that the power receiving device 103 is present in the power transmission range 102 of the power transmission device 101. The detection unit 209 can also detect which power receiving device 103 is present at which position within the power transmission range.

  The power receiving apparatus 103 is configured to include a power receiving antenna 210, a power receiving unit 211, a communication antenna 212, a communication unit 213, a power receiving control unit 214, a UI (user interface) 215, a storage unit 216, a communication control unit 217, and a detection unit 218. Be done. The power reception control unit 214 controls the power reception unit 211 such that the power transmitted by the WPT method determined by the power transmission apparatus 101 can be received. A chargeable battery is connected to the power reception control unit 214, and the power reception control unit 214 charges the battery with the power received by the power reception unit 211. However, the power reception control unit 214 can also control to use the power received from the power transmission apparatus 101 not as the charging of the battery but directly as the power supply of the processor.

  The UI 215 is an interface for the user to perform various settings on the power receiving apparatus 103. The storage unit 216 is used, for example, to store information on settings input from the UI 215. The communication control unit 217 controls the communication unit 213 to realize communication with the power transmission device 101. The communication unit 213 implements communication with the power transmission device 101 via the communication antenna 212 according to control from the communication control unit 217. In the present embodiment, it is possible to use the communication unit 213 to perform communication regarding various controls for wireless power transmission.

  The power receiving apparatus 103 shown in FIG. 2 supports the first WPT method and the second WPT method shown in Table 1. Further, the power receiving apparatus 103 in FIG. 2 includes two power receiving antennas 210 and two power receiving units 211. However, in the present embodiment, a plurality of power receiving devices 103 such as the power receiving device 103 compatible with only one WPT method and the power receiving devices 103 compatible with three WPT methods fall within the power transmission range 102 of the power transmitting device 101. It is assumed that there is a case. Further, in the case where the power receiving antenna 210 and the power receiving unit 211 can be shared by the first WPT method and the second WPT method, the power receiving device 103 can be realized by one power receiving antenna 210 and the power receiving unit 211.

  Next, operations of the power transmission device 101 and the power reception device 103 in the present embodiment will be described using the sequence diagram of FIG. 3. FIG. 3 is a sequence diagram for explaining the operation of the power transmission device 101 and the power reception device 103 according to the present embodiment. In S301 of FIG. 3, the power transmitting apparatus 101 determines whether or not the power receiving apparatus exists in the power transmission range 102 (within the predetermined range). When it is determined that the power receiving apparatus 103-1 exists within the power transmission range (YES in S301), the power transmitting apparatus 101 identifies the WPT method supported by the power receiving apparatus 103-1 and the power receiving apparatus 103-1. Negotiation is performed (S302).

  Although the method of specifying the WPT method is not particularly limited, there are the following methods. For example, the power transmitting apparatus 101 transmits an inquiry signal of each of the first, second, and third WPT methods to the power receiving apparatus 103-1, and the power receiving apparatus 103-1 receives a response from the power receiving apparatus 103-1. Identify supported WPT methods. When the power transmitting apparatus 101 receives the response of the first inquiry signal and the response of the second inquiry signal from the power receiving apparatus 103-1, the power receiving apparatus 103-1 supports the first WPT method and the second WPT method. It is determined that The first WPT method inquiry signal is a signal according to the communication method or format defined as the first WPT method. Further, the second WPT method inquiry signal is a signal conforming to the communication method and format defined as the second WPT method, and the third WPT method inquiry signal is defined as the third WPT method. Signals according to the communication method and format. Further, as another method for specifying the WPT method supported by the power receiving apparatus 103-1, for example, there is a method of transmitting an inquiry message from the power transmitting apparatus 101. The power receiving apparatus 103-1 having received the inquiry message transmits, as a response, identification information of the WPT method supported by itself. Even in this case, the power transmission device 101 can specify the WPT method supported by the power reception device 103-1.

  If the power transmission apparatus 101 determines that the power receiving apparatus 103-1 supports a plurality of WPT methods among the first, second, and third WPT methods, which WPT method should be used to transmit power. decide. Although the method of determining the WPT method is not particularly limited, for example, the power transmitting apparatus 101 can determine the WPT method capable of simultaneously transmitting power to more power receiving apparatuses as the WPT method used for power transmission to the power receiving apparatus 103-1. It is. Using the above determination method, when the power receiving apparatus 103-1 supports the first WPT method and the second WPT method, the power transmitting apparatus 101 receives the power receiving apparatus according to the second WPT method based on Table 1. Decide to transmit power to 103-1. However, this is not the case in the case where power transmission has already been performed to another power reception device 103 -X by the second WPT method.

  Further, as an example of another determination method, the power transmission device 101 can determine the WPT method in which the amount of power that can be transmitted is larger as the WPT method used for power transmission to the power reception device 103-1. According to the above determination method, when the power receiving device 103-1 supports the first WPT method and the second WPT method, the power transmitting device 101 receives the power receiving device according to the second WPT method based on Table 1 Decide to transmit power to 103-1. However, this is not the case in the case where power transmission has already been performed to another power reception device 103 -X by the second WPT method.

  After determining the WPT method used for power transmission to the power receiving device 103-1, the power transmission device 101 performs negotiation with the power receiving device 103-1 according to the WPT method. In the negotiation in the present embodiment, the power transmission device 101 acquires control information such as the charge status (0% to 100%) of the power reception device 103-1, required power (for example, 5 W), and current power consumption from the power reception device 103-1. Do. Then, the power transmission apparatus 101 determines parameters such as a current value, a voltage value, and a drive frequency to be supplied to the power transmission antenna 206 based on the acquired various information related to the power reception apparatus 103-1. When the negotiation is completed, power transmission from the power transmitting apparatus 101 to the power receiving apparatus 103-1 is performed (S303).

  After the start of power transmission, the power transmitting apparatus 101 determines whether a new power receiving apparatus 103-N is present in the power transmission range 102 (within the predetermined range) (S304). If the power transmission device 101 determines that the power reception device 103-N does not exist (NO in S304), it determines whether or not the power transmission should be terminated, and performs the power transmission termination processing when it is determined that the power transmission should be terminated. . On the other hand, when determining that the power transmission should not be ended, the power transmission apparatus 101 continues the power transmission to the power receiving apparatus 103-1. The termination conditions of power transmission include, for example, various errors of the power transmission apparatus 101, full charge of the power reception apparatus 103-1, and time errors due to the power reception apparatus 103-1 being separated from the power transmission range 102.

  If the power transmission apparatus 101 determines that a new power reception apparatus 103-N exists in the power transmission range 102 (YES in S304), it identifies a WPT method supported by another power reception apparatus 103-N (S305). Although the method of specifying the WPT method is not particularly limited, it is possible to use, for example, a method similar to the method of specifying the WPT method supported by the power receiving apparatus 103-1. In addition, when it is determined that the power receiving apparatus 103 -N supports a plurality of WPT methods among the first, second, and third WPT methods, the power transmitting apparatus 101 performs power transmission using any of the WPT methods. Decide. Further, after determining the WPT method to be used for power transmission to the power receiving device 103-N, the power transmitting device 101 acquires predetermined information such as the required power of the power receiving device 103-N from the power receiving device 103-N. This information is used to determine whether to change the WPT method used by the power transmitting apparatus 101 to transmit power to the power receiving apparatus 103-1. When the power transmitting apparatus 101 acquires predetermined information from the power receiving apparatus 103-N, the process proceeds to S306.

  The power transmission device 101 uses the WPT method used for power transmission to the power reception device 103-N and the WPT method used for power transmission to the power reception device 103-1 based on the predetermined information acquired from the power reception device 103-N in S305. It is determined whether or not to change (S306). Details of the determination method of the change of the WPT method will be described later. When it is determined that the WPT method used for power transmission to the power receiving device 103-1 is changed (YES in S306), the power transmitting device 101 negotiates with the power receiving device 103-1 after determining the WPT method after the change (S307) . When it is determined that the power transmission apparatus 101 does not change the WPT method (NO in S306), the process of S307 is not performed. After that, the power transmitting apparatus 101 negotiates with the power receiving apparatus 103-N (S308). When the negotiation of the power transmission device 101 and the power reception device 103-N is completed, the power transmission device 101 starts power transmission to the power reception device 103-1 and the power reception device 103-N (S309).

  Next, the operation of the power transmission device 101 of the present embodiment will be described using FIG. 4. FIG. 4 is a flowchart for explaining the operation of the power transmission device 101 according to the present embodiment. The power transmission device 101 according to the present embodiment realizes the operation illustrated in FIG. 4 by reading out a program required by a CPU (not shown) from the ROM and executing the program. Note that the power transmission device 101 of the present embodiment is a power transmission device that supports a plurality of wireless power transmission methods (WPT methods). That is, the power transmitting apparatus 101 can transmit wireless power to the power receiving apparatus 103 by the first WPT method, and can also transmit wireless power to the power receiving apparatus 103 by the second WPT method. It is also possible to perform power transmission to the power receiving device 103 by the third WPT method. In addition, the power transmission apparatus 101 of the present embodiment starts the process of S401 when the power supply of the power transmission apparatus 101 is turned on.

  In S401 of FIG. 4, the detection unit 209 of the power transmission device 101 detects the power reception device 103 (power reception device 103-1) present in the power transmission range 102 (within the predetermined range). If the detecting unit 209 determines that a new power receiving apparatus 103-1 exists in the power transmission range 102 (YES in S401), the process proceeds to S402. In step S402, the power transmission control unit 201 identifies the WPT method supported by the power receiving apparatus 103-1 detected in step S401. Although the method of specifying the WPT method is not limited, for example, the communication unit 207 of the power transmission apparatus 101 sends a WPT related signal (the first inquiry signal, the second inquiry signal, and the third inquiry signal described above) to the power receiving apparatus 103. There is a way to send The power transmitting apparatus 101 can specify the WPT method supported by the power receiving apparatus 103 based on the presence or absence of the response from the power receiving apparatus 103 to the WPT related signal and / or the content of the response. As an example of the WPT related signal, there are a connection request and a Ping signal defined in each of the first, second and third WPT methods. Further, as another example of the WPT related signal, there is a message for inquiring the WPT method supported by the power receiving apparatus 103 (the above-mentioned inquiry message). The power receiving apparatus 103-1 having received the message transmits the identification information of the WPT method supported by itself as a response message to the power transmitting apparatus 101.

  When the specification of the WPT method supported by the power receiving apparatus 103-1 is finished, the process proceeds to S403. In step S403, the power transmission control unit 201 negotiates with the power reception control unit 214 of the power receiving apparatus 103-1 regarding wireless power transmission. When there are a plurality of WPT methods supported by both the power transmitting apparatus 101 and the power receiving apparatus 103-1, the power transmission control unit 201 determines the WPT method to be used for power transmission to the power receiving apparatus 103-1 before executing the negotiation. Do. Although the method of determining the WPT method is not particularly limited, as described above, for example, the power transmitting apparatus 101 determines the WPT method capable of simultaneously transmitting power to more power receiving apparatuses as the WPT method using power transmission to the power receiving apparatus 103-1. It is possible. Further, as another determination method, the power transmission device 101 can determine the WPT method in which the amount of power that can be transmitted is larger as the WPT method used for power transmission to the power reception device 103-1.

  After determining the WPT method used for power transmission to the power receiving device 103-1, the power transmission device 101 performs negotiation with the power receiving device 103-1 according to the WPT method. In the negotiation in the present embodiment, the power transmission control unit 201 transmits control information such as the charge status (0% to 100%) of the power receiving device 103-1, required power (for example, 5 W), and current power consumption from the power receiving device 103-1. get. Then, the power transmission control unit 201 determines parameters such as a current value, a voltage value, and a driving frequency to be supplied to the power transmission antenna 206 based on the acquired various information related to the power receiving device 103-1. When the negotiation is completed, power transmission from the power transmission unit 205 to the power reception unit 211 is performed (S404: power transmission procedure).

  After the start of power transmission, the detection unit 209 of the power transmission apparatus 101 determines whether or not a new power reception apparatus 103 (power reception apparatus 103 -N) is detected within the power transmission range 102. If the detection unit 209 detects the power receiving apparatus 103 -N within the power transmission range (within the predetermined range) (YES in S405), the process proceeds to S407, and if not detected (NO in S405), the process proceeds to S406. In step S406, the power transmitting apparatus 101 determines whether to end the power transmission to the power receiving apparatus 103. When it is determined that the power transmission to all the power receiving apparatuses 103 is to be ended (YES in S406), the power transmission control unit 201 performs power transmission end processing in S411, and ends the processing in FIG. When it is determined that the power transmission to some of the power receiving devices 103 is ended (NO in S406), the power transmission device 101 performs the power transmission ending process to some of the power receiving devices 103, and returns to S404. The termination conditions of power transmission include, for example, various errors of the power transmission apparatus 101, full charge of the power reception apparatus 103, and time errors due to the power reception apparatus 103 being separated from the power transmission range 102.

  In step S407, the power transmission control unit 201 identifies the WPT method supported by the power receiving apparatus 103-N. Although the method of specifying the WPT method is not particularly limited, it is possible to use, for example, a method similar to the method of specifying the WPT method supported by the power receiving apparatus 103-1. When the power transmission control unit 201 determines that the power receiving apparatus 103 -N supports a plurality of WPT methods among the first, second, and third WPT methods, power transmission is performed using any WPT method. Decide what to do. In addition, after determining the WPT method used for power transmission to the power receiving device 103-N, the power transmission control unit 201 acquires predetermined information such as required power of the power receiving device 103-N from the power receiving device 103-N. This information is used to determine whether the power transmission control unit 201 changes the WPT method used for power transmission to the power receiving device 103-1. When the power transmission control unit 201 acquires predetermined information from the power receiving apparatus 103-N, the process proceeds to step S408.

  The power transmission device 101 uses the WPT method used for power transmission to the power reception device 103-N and the WPT method used for power transmission to the power reception device 103-1 based on the predetermined information acquired from the power reception device 103-N in S407. It is judged whether it changes (S408). The determination method of the change of the WPT method in this embodiment is demonstrated using FIG. FIG. 9 is a flowchart for explaining the determination process (S408) as to whether or not to change the WPT method. As shown in Table 1, the power transmission apparatus 101 can transmit power of 5 W at maximum with the first WPT method, and can transmit power of 20 W at maximum with the second WPT method. The third WPT method Power transmission of up to 50W is possible.

  In S901 of FIG. 9, the power transmission control unit 201 determines whether power transmission to the power receiving apparatus 103 -N newly detected in S405 is possible. When power transmission can be performed according to the required power of the new power receiving apparatus 103-N without changing the WPT method (YES in S901), it is determined not to change the WPT method (S906), and the process proceeds to S409 in FIG. On the other hand, if it is not possible to transmit power to a new power receiving device 103 -N unless the WPT method used for power transmission to the power receiving device 103 being received is changed (NO in S901), the process proceeds to S902. The power receiving device 103 receiving power is a power receiving device which is detected by the power transmitting device 101 before the power receiving device 103 -N is detected, and receives the wireless power supply from the power transmitting device 101.

  In step S <b> 902, the power transmission control unit 201 determines whether the power receiving device 103 receiving power supports a WPT method other than the WPT method currently used. For example, when the power transmitting apparatus 101 is transmitting power to the power receiving apparatus 103-1 according to the first WPT method, the power transmission control unit 201 determines whether the power receiving apparatus 103-1 supports the second and third WPT methods It is determined whether or not. When a plurality of power receiving devices are receiving power, the power transmission control unit 201 determines whether any of the power receiving devices 103 among the power receiving devices 103 that are receiving power supports the second and third WPT methods. If the power transmission control unit 201 determines that the power receiving apparatus 103 currently receiving power does not support a WPT method other than the WPT method currently used (NO in S902), it is determined that the WPT method is not changed (S906), It progresses to S409 of FIG. On the other hand, if the power transmission control unit 201 determines that at least one of the power receiving apparatuses 103 currently receiving power supports a WPT system other than the current WPT system (YES in S902), the process proceeds to S903.

  In step S903, the power transmission control unit 201 determines whether power transmission according to the power required by the power receiving apparatus 103 is possible even if the WPT method used for power transmission to the power receiving apparatus 103 being received is changed. Do. For example, when the power transmitting apparatus 101 is transmitting power of 5 W to the power receiving apparatus 103-1 in the first WPT method, even if the WPT method is changed from the first WPT method to the second or third WPT method, It is determined whether power transmission of 5 W is possible with respect to the power receiving apparatus 103-1. In addition, the power transmission control unit 201 receives power based on the number of power transmission possibilities to a plurality of power reception devices shown in Table 1 and the number of power reception devices 103 currently targeted by the power transmission device 101 to transmit power. It is determined whether it is possible to change the WPT method used for power transmission to the internal power receiving apparatus 103. For example, the power transmitting apparatus 101 transmits power to one power receiving apparatus 103-1 (supporting the first and second WPT systems) by the first WPT method, and three power receiving apparatuses 103-2 by the second WPT method. , 3 and 4, the power transmission control unit 201 determines as follows. That is, when the power transmission control unit 201 changes the WPT method used for power transmission to the power receiving device 103-1, the power transmission control unit 201 determines that power transmission according to the required power to the power receiving device 103-1 can not be performed. However, if the power transmission control unit 201 can change at least one of the power receiving apparatuses 103-2, 3 and 4 to the third WPT system, the WPT system used for power transmission to the power receiving apparatus 103-1 is used. It is determined that power transmission can be performed according to the required power of the power receiving apparatus 103-1 even if the power is changed.

  If the power transmission control unit 201 determines that power transmission according to the required power to the power receiving device 103 can not be performed if the WPT method used for power transmission to the power receiving device 103 being received is changed (NO in S903), the WPT method is selected. It is determined not to change (S906), and the process proceeds to S409 in FIG. On the other hand, when the power transmission control unit 201 determines that power transmission can be performed according to the required power to the power receiving device 103 even if the WPT method used for power transmission to the power receiving device 103 being received is changed (YES in S903) , S904. In S904, if the power transmission control unit 201 changes the WPT method used for power transmission to the power receiving apparatus 103 while receiving power, whether power transmission according to the required power of the new power receiving apparatus 103-N becomes possible Determine if For example, when the power transmitting apparatus 101 is transmitting power of 5 W to the power receiving apparatus 103-1 in the first WPT method, and the required power of the new power receiving apparatus 103-N is 5 W, the power transmission control unit 201 changes the WPT method. It is determined that power transmission to the new power receiving apparatus 103-N becomes possible. On the other hand, when the required power of the new power receiving apparatus 103-N is 10 W, the power transmission control unit 201 determines that power transmission according to the required power of the new power receiving apparatus 103-N can not be performed even if the WPT method is changed. .

  When the power transmission control unit 201 determines that power transmission according to the required power of the new power receiving device 103-N can not be performed even if the WPT method used for power transmission to the power receiving device 103 being received is changed (NO in S904 And the WPT method is not changed (S906), and the process proceeds to S409 in FIG. On the other hand, if the power transmission control unit 201 determines that power transmission can be performed according to the required power of the new power receiving device 103 -N by changing the WPT method used for power transmission to the power receiving device 103 while receiving power ( The processing advances to step S905. In step S905, the power transmission control unit 201 determines to change the WPT method used for power transmission to the power receiving apparatus 103 which is receiving power, and the process advances to step S403 in FIG.

  According to the determination method described above, the power transmission control unit 201 can transmit power by the first WPT method when transmitting power by the first WPT method (first wireless power transmission method) to the new power receiving apparatus 103 -N It is determined whether the amount of power is exceeded. Then, the power transmission control unit 201 changes the WPT method used for power transmission to the power receiving device 103-1 from the first WPT method to the second WPT method according to the result of the above determination. In the above description, although the case where the first WPT method is changed to the second WPT method is described, the present invention is not limited to this. For example, the second WPT method may be changed to the first WPT method, or the third WPT method may be changed to the second WPT method.

  Returning to FIG. 4, when the power transmitting apparatus 101 determines to change the WPT method used for power transmission to the power receiving apparatus 103-1 (YES in S408), after determining the changed WPT system, the power transmitting apparatus 101 negotiates with the power receiving apparatus 103-1. (S403: control procedure). When the power transmission from the power transmitting apparatus 101 to the power receiving apparatus 103-1 is resumed after the negotiation in S403, it is determined in the next S405 that another power receiving apparatus 103-N is present, S407 is skipped, and the determination result in S408 Becomes "NO". Accordingly, the power transmission control unit 201 of the power transmission apparatus 101 negotiates with the power receiving apparatus 103-N (S409). When the negotiation of the power transmitting apparatus 101 and the power receiving apparatus 103-N is completed, the power transmitting apparatus 101 determines whether to end the power transmission (S410). For example, when the negotiation between the power transmission apparatus 101 and the other power reception apparatus 103-N ends in failure, the determination result in S410 is "YES", and the power transmission end process is performed (S411). When it is determined that the power transmission is not ended in S410 (NO in S410), the power transmission control unit 201 starts power transmission to the power receiving device 103-1 and the power receiving device 103-N (S404).

  As described above, when changing the WPT method used for power transmission to the power receiving device 103-1, the power transmission device 101 according to the present embodiment moves to another power receiving device 103-N after the negotiation of the changed WPT method is completed. Start the negotiation of By doing this, if the change of the WPT method used for power transmission to the power reception device 103-1 fails, the power transmission device 101 uses the WPT method before change for the power transmission to the power reception device 103-1. Can be returned to However, the negotiation with the power receiving apparatus 103 -N does not necessarily have to be started after the negotiation of the post-change WPT scheme is completed. For example, when the power transmission control unit 201 of the power transmission apparatus 101 receives from the power receiving apparatus 103-1 a predetermined signal (for example, a positive response to the connection request) regarding control of the WPT method after the change, negotiation with the power receiving apparatus 103-N is performed. You may start it. In this way, the timing of the start of power transmission to the power reception device 103 -N can be advanced.

  Also, for example, before the power transmission apparatus 101 receives from the power receiving apparatus 103-1 a predetermined signal related to control of the WPT system after the change, which is timing after changing the WPT method used for power transmission to the power receiving apparatus 103-1. Power transmission to the power receiving device 103 -N may be started at the timing of In this way, the timing of the start of power transmission to the power reception device 103 -N can be further advanced.

  In addition, when the power transmission control unit 201 of the power transmission device 101 according to the present embodiment changes the WPT method used for power transmission to the power reception device 103-1, when the charging of the power reception device 103-N is completed, the power reception device 103-1. Return the WPT method used for power transmission to before changing. By doing this, it is possible to transmit power by the WPT method selected first as the WPT method used for power transmission to the power receiving device 103-1. However, it is also possible that the power transmission control unit 201 does not return the WPT method before the change. If it is not returned before the change, the load to change the WPT method can be reduced.

  Subsequently, the operation of the power receiving device 103 according to the present embodiment will be described with reference to FIG. FIG. 5 is a flowchart for explaining the operation of the power receiving device 103 according to the present embodiment. The power receiving apparatus 103 according to the present embodiment realizes the operation illustrated in FIG. 5 by reading out a program that requires a CPU (not shown) from the ROM and executing the program. Note that the power receiving apparatus 103 in the present embodiment supports at least one WPT method among the first, second, and third WPT methods (wireless power transmission method). That is, the power reception device 103 can receive power supply from the power transmission device 101 using at least one of the first, second, and third WPT methods. The power receiving apparatus 103 according to the present embodiment starts the process illustrated in FIG. 5 when the user sets the power receiving mode. However, for example, the process of FIG. 5 may be started in response to power on of the power receiving apparatus 103. Further, in the following description, an operation of the power receiving device 103-1 when the first power receiving device 103-1 enters the power transmission range 102 of the power transmission device 101 will be mainly described.

  In step S501, the power reception control unit 214 of the power receiving apparatus 103-1 determines whether a WPT related signal has been received from the power transmission apparatus 101. The WPT related signal is, for example, a connection request or Ping signal defined in each of the first, second, and third WPT methods. However, the message is not limited to this example, and may be, for example, a message for inquiring the WPT method supported by the power receiving apparatus 103-1. The communication unit 213 of the power receiving apparatus 103-1 transmits a response to the WPT related signal to the power transmission apparatus 101 according to the WPT method supported by itself.

  For example, when the power receiving apparatus 103-1 supports the first and second WPT methods and does not support the third WPT method, the response of the WPT related signal of the first and second WPT methods is transmitted. , Does not transmit the response of the WPT related signal of the third WPT method. Alternatively, the power receiving apparatus 103-1 transmits an error message to the power transmitting apparatus 101 as a response to the WPT related signal of the third WPT method. Also, when a message for inquiring the WPT method supported by the power receiving apparatus 103-1 is received as a WPT related signal, the power receiving apparatus 103 transmits a response message including identification information of the WPT method supported by itself. Transmit to the device 101. When the power receiving apparatus 103-1 supports the first and second WPT methods, a response message including identification information of the first and second WPT methods is transmitted to the power transmission apparatus 101.

  In step S <b> 502, the power reception control unit 214 negotiates with the power transmission apparatus 101. In the negotiation in the present embodiment, the power transmission device 101 acquires control information such as the charge status (0% to 100%) of the power reception device 103-1, required power (for example, 5 W), and current power consumption from the power reception device 103-1. Do. Then, the power transmission control unit 201 of the power transmission apparatus 101 determines parameters such as the current value, the voltage value, and the driving frequency to be supplied to the power transmission antenna 206 based on the acquired various information on the power receiving apparatus 103-1. When the negotiation is completed, power transmission is started from the power transmission apparatus 101, and the power reception apparatus 103-1 starts power reception (S503).

  The power reception control unit 214 determines whether or not the WPT method change notification has been received from the power transmission apparatus 101 after power reception has been started (S504). The change notification includes the identification information of the WPT method after the change. The change notification may be a signal for the end of power transmission defined by the WPT method before the change and a signal for the start of power transmission defined by the WPT method after the change. When the communication unit 213 of the power receiving apparatus 103 receives the WPT method change notification (YES in S504), the process returns to S502, and the power reception control unit 214 performs negotiation for receiving power according to the changed WPT method with the power transmitting apparatus 101. Run with On the other hand, if the communication unit 213 does not receive the WPT method change notification (NO in S504), the process proceeds to S505.

  In step S505, the power reception control unit 214 determines whether to end the power reception. The determination conditions of the power reception end include various errors and full charge on the power reception device 103-1 side, reception of a power transmission end signal from the power transmission device 101, and the like. When the power reception is ended in S505 (YES in S505), when the power reception control unit 214 determines that the process proceeds to S506, the power reception end process is performed, and the process of FIG. 5 is ended. If the power reception control unit 214 determines that the power reception is not ended in S505 (NO in S505), the process returns to S503, and the power reception is continued.

  As described above, the power transmission device 101 according to the present embodiment detects the WPT method used for power transmission to the power reception device 103-1 detected by the detection unit 209 after the power reception device 103-1. Change according to the WPT method supported by -2. By doing this, it is possible to improve the efficiency of wireless power transmission in a system in which a plurality of wireless power transmission schemes (WPT schemes) are supported.

  In the above embodiment, the WPT method used for power transmission to the power receiving device 103-1 is different from the WPT method used for power transmission to the power receiving device 103-1 and the WPT method used for power transmission to the power receiving device 103-N. Although the description has been made centering on the modified example, the present invention is not limited to this example. That is, the power transmission control unit 201 of the power transmission apparatus 101 receives the power receiving apparatus 103 so that the WPT method used for power transmission to the power receiving apparatus 103-1 and the WPT method used for power transmission to the power receiving apparatus 103-N are the same. It is also possible to change the WPT method used for power transmission to -1.

  For example, while the power transmitting apparatus 101 transmits power to the power receiving apparatus 103-1 in the first WPT method, the power receiving apparatus 103-N that does not support the first WPT method but supports the second WPT method is a power transmitting apparatus. There may be cases where it is determined to be within the power transmission range 102 of 101. In this case, the power transmission control unit 201 of the power transmission device 101 changes the WPT method used for power transmission to the power receiving device 103-1 from the first WPT method to the second WPT method. By doing this, the WPT method used for power transmission to the power receiving device 103-1 and the power receiving device 103-N can be unified to the second WPT method, so that wireless power transmission with high efficiency can be performed. Become.

Second Embodiment
Next, a second embodiment of the present invention will be described focusing on differences from the first embodiment. In the present embodiment, the power receiving apparatus 103 that is receiving power controls the change of the WPT method used for power reception according to the WPT method (wireless power transmission method) supported by the newly detected power receiving apparatus 103 -N.

  The operations of the power transmission device 101 and the power reception device 103 in the present embodiment will be described using the sequence diagram of FIG. FIG. 6 is a sequence diagram for explaining the operation of the power transmission device 101 and the power reception device 103 according to the present embodiment. In S601 of FIG. 6, the power receiving apparatus 103-1 determines whether or not the power transmission apparatus itself exists within the power transmission range 102 (within the predetermined range) of the power transmission apparatus 101. If it is determined that the power receiving apparatus 103-1 exists within the power transmission range of the power transmitting apparatus 101 (YES in S601), the power receiving apparatus 103-1 identifies the WPT method supported by the power transmitting apparatus 101 and transmits the power. Negotiate with 101 (S602). The method of specifying the WPT method is not particularly limited. For example, the power receiving apparatus 103-1 can transmit an inquiry signal of each of the WPT methods supported by itself to the power transmitting apparatus 101. Then, the power reception device 103-1 can specify the WPT method supported by the power transmission device 101 by the response from the power transmission device 101 to the inquiry signal. Further, as another method for specifying the WPT method supported by the power transmission apparatus 101, for example, there is a method of transmitting an inquiry message from the power receiving apparatus 103-1. The power transmission apparatus 101 having received the inquiry message transmits, as a response, identification information of the WPT method supported by itself. Even in this case, the power receiving apparatus 103-1 can specify the WPT method supported by the power transmitting apparatus 101.

  Also, when it is determined that there are a plurality of WPT methods that also support the power transmission device 101 among the WPT methods that the power receiving device 103-1 supports, the power receiving device 103-1 determines which WPT method is used to transmit power. . Although the method of determining the WPT method is not particularly limited, for example, the power receiving device 103-1 may determine the WPT method capable of simultaneously transmitting power to more power receiving devices as the WPT method used for power transmission to the power receiving device 103-1. Is possible. When both the power transmission apparatus 101 and the power reception apparatus 103-1 support the first and second WPT methods using the above determination method, the power transmission apparatus 101 uses the second WPT method to receive the power reception apparatus 103-1. Power will be transmitted. However, this is not the case when power is already transmitted to another power receiving apparatus 103 -X by the second WPT method.

  Further, as an example of another determination method, the power receiving device 103-1 can determine the WPT method in which the amount of power that can be transmitted is larger as the WPT method used for power transmission to the power receiving device 103-1. When both the power transmission apparatus 101 and the power reception apparatus 103-1 support the first and second WPT methods using the above determination method, the power transmission apparatus 101 uses the second WPT method to receive the power reception apparatus 103-1. Power will be transmitted. However, this is not the case when power is already transmitted to another power receiving apparatus 103 -X by the second WPT method.

  After determining the WPT method used for power transmission from the power transmission device 101 to the power reception device 103-1, the power reception device 103-1 performs negotiation with the power transmission device 101 in accordance with the WPT method. In the negotiation in the present embodiment, the power transmission device 101 acquires control information such as the charge status (0% to 100%) of the power reception device 103-1, required power (for example, 5 W), and current power consumption from the power reception device 103-1. Do. Then, the power transmission apparatus 101 determines parameters such as a current value, a voltage value, and a drive frequency to be supplied to the power transmission antenna 206 based on the acquired various information related to the power reception apparatus 103-1. When the negotiation is completed, power transmission from the power transmitting apparatus 101 to the power receiving apparatus 103-1 is performed (S603).

  After the start of power transmission, the power receiving apparatus 103-1 determines whether the power receiving apparatus 103-N exists in the power transmission range 102 (within the predetermined range) of the power transmission apparatus 101 (S604). If the power receiving apparatus 103-1 determines that there is no other power receiving apparatus 103-N (NO in S604), it determines whether or not power reception should be ended, and if it is determined that power reception should be ended, the power reception ends Do the processing. On the other hand, when it is determined that the power reception should not be ended, the power reception apparatus 103-1 continues the power reception from the power transmission apparatus 101. The determination condition of the power reception end includes, for example, various errors of the power receiving device 103-1, full charge of the power receiving device 103-1, and a time error due to the power receiving device 103-1 being separated from the power transmission range 102.

  If the power receiving apparatus 103-1 determines that another power receiving apparatus 103-N exists in the power transmission range 102 of the power transmitting apparatus 101 (YES in S604), the WPT method supported by the other power receiving apparatus 103-N is selected. It identifies (S605). Although there is no particular limitation on the method of specifying the WPT method, there is a method of transmitting an inquiry signal of each of a plurality of WPT methods and specifying using a response from another power receiving apparatus 103 -N. Further, as a method of specifying the WPT method, a method of transmitting an inquiry message for inquiring the support status of the WPT method from the power transmitting device 101 to the power receiving device 103-N and specifying by a response from the power receiving device 103-N can be considered. However, it is not limited to these methods.

  When the power receiving apparatus 103-1 determines that the power receiving apparatus 103 -N supports a plurality of WPT methods among the first, second, and third WPT methods supported by the power transmitting apparatus 101. It is determined which WPT method is used to transmit power to the power receiving apparatus 103 -N. Further, after determining the WPT method used for power transmission to the power receiving device 103-N, the power receiving device 103-1 acquires predetermined information such as the required power of the power receiving device 103-N from the power receiving device 103-N. This information is used to determine whether to change the WPT method used by the power transmitting apparatus 101 to transmit power to the power receiving apparatus 103-1. If the power receiving apparatus 103-1 acquires predetermined information from the power receiving apparatus 103-N, the process advances to step S606.

  The power receiving apparatus 103-1 uses the WPT method used for power transmission to the power receiving apparatus 103-N, and WPT used for power transmission to the power receiving apparatus 103-1 based on the predetermined information acquired from the power receiving apparatus 103-N in S605. It is determined whether the method is to be changed (S606). Details of the determination method of the change of the WPT method will be described later. If it is determined that the WPT method used for power transmission to the power receiving device 103-1 is changed (YES in S606), the power receiving device 103-1 negotiates with the power transmitting device 101 after determining the changed WPT method (S607) . When it is determined that the power receiving apparatus 103-1 does not change the WPT method (NO in S606), the process of S607 is not performed. After that, negotiation is performed between the power transmission device 101 and the power reception device 103-N (S608). When the negotiation of the power transmission device 101 and the power reception device 103-N is completed, the power transmission device 101 starts power transmission to the power reception device 103-1 and the power reception device 103-N (S609).

  Subsequently, the operation of the power transmission device 101 of the present embodiment will be described next with reference to FIG. FIG. 7 is a flowchart for explaining the operation of the power transmission device 101 according to the present embodiment. The power transmission device 101 according to the present embodiment realizes the operation illustrated in FIG. 7 by reading and executing a program required by a CPU (not shown) from the ROM. Note that the power transmission device 101 of the present embodiment is a power transmission device that supports a plurality of wireless power transmission methods (WPT methods). That is, the power transmitting apparatus 101 can transmit wireless power to the power receiving apparatus 103 by the first WPT method, and can also transmit wireless power to the power receiving apparatus 103 by the second WPT method. It is also possible to perform power transmission to the power receiving device 103 by the third WPT method. In addition, the power transmission apparatus 101 of the present embodiment starts the process of S701 when its own power is turned on.

  In step S701, the power transmission control unit 201 of the power transmission apparatus 101 determines whether a WPT related signal has been received from the power receiving apparatus 103. The WPT related signal is, for example, a connection request or Ping signal defined in each of the first, second, and third WPT methods. For example, it is a message for inquiring the WPT method which the power transmission apparatus 101 supports. The communication unit 207 of the power transmission apparatus 101 transmits a response to the WPT related signal to the power receiving apparatus 103-1 according to the WPT method supported by itself. For example, when the power receiving apparatus 103-1 supports the first and second WPT methods, connection requests of the first and second WPT methods are transmitted. The power transmitting apparatus 101 transmits a response to the connection request of the first and second WPT methods to the power receiving apparatus 103-1. When a message for inquiring the support status of the WPT method is received as a WPT related signal (YES in S701), the power transmitting apparatus 101 supports the WPT method supported by itself (first, second, and third WPT methods) Is transmitted to the power receiving apparatus 103-1.

  In step S702, the power transmission control unit 201 negotiates with the power receiving apparatus 103-1. In the negotiation in the present embodiment, the power transmission device 101 acquires control information such as the charge status (0% to 100%) of the power reception device 103-1, required power (for example, 5 W), and current power consumption from the power reception device 103-1. Do. Then, the power transmission control unit 201 of the power transmission apparatus 101 determines parameters such as the current value, the voltage value, and the driving frequency to be supplied to the power transmission antenna 206 based on the acquired various information on the power receiving apparatus 103-1. When the negotiation is completed, power transmission is started from the power transmitting apparatus 101, and the power receiving apparatus 103-1 receives the power (S703).

  After the power transmission control unit 201 starts power transmission to the power receiving device 103-1, the power transmission control unit 201 determines whether a WPT related signal has been received from another power receiving device 103-N (S704). The WPT related signal in this embodiment is, for example, a connection request or Ping signal defined in each of the first, second, and third WPT methods, as described in S701. Further, for example, the WPT related signal is a message for inquiring the WPT method supported by the power transmission apparatus 101. If the power transmission control unit 201 determines in S704 that the WPT related signal is not received from the power receiving apparatus 103-N (NO in S704), the process proceeds to S705, and it is determined that the WPT related signal is received from the power receiving apparatus 103-N. If it is (YES in S704), the process proceeds to S702. In S702, the power transmission control unit 201 negotiates with the power receiving device 103-N as in the case of the power receiving device 103-1, and when the negotiation is successful, starts power transmission to the power receiving device 103-N.

  In step S705, the power transmission control unit 201 determines whether a WPT method change notification has been received from the power receiving apparatus 103-1. The change notification includes the identification information of the WPT method after the change. The change notification may be a signal for the end of power transmission defined by the WPT method before the change and a signal for the start of power transmission defined by the WPT method after the change. When the communication unit 207 of the power transmission apparatus 101 receives the WPT method change notification (YES in S705), the process returns to S702, and the power transmission control unit 201 performs negotiation for power transmission by the changed WPT method with the power receiving apparatus 103-1. Run between On the other hand, if the communication unit 207 does not receive the WPT method change notification (NO in S705), the process proceeds to S706.

  In step S706, the power transmission control unit 201 determines whether to end power transmission. The determination conditions of the power transmission termination include various errors on the power transmission apparatus 101 side, reception of a power reception termination signal from the power reception apparatus 103, and the like. When the power transmission control unit 201 determines that power transmission is ended in S706 (YES in S706), the process proceeds to S707, performs power transmission end processing, and ends the processing of FIG. When the power transmission control unit 201 determines that the power transmission is not ended in S706 (NO in S706), the process returns to S703, and the power transmission is continued.

  Subsequently, the operation of the power receiving device 103 in the present embodiment will be described with reference to FIG. FIG. 8 is a flowchart for explaining the operation of the power receiving device 103 according to the present embodiment. The power receiving device 103 according to the present embodiment realizes the operation illustrated in FIG. 8 by reading out a program required by a CPU (not shown) from the ROM and executing the program. Note that the power receiving apparatus 103 in the present embodiment supports at least one WPT method among the first, second, and third WPT methods (wireless power transmission method). That is, the power reception device 103 can receive power supply from the power transmission device 101 using at least one of the first, second, and third WPT methods. In addition, the power receiving device 103 according to the present embodiment starts the process illustrated in FIG. 8 when the user sets the power receiving mode. However, for example, the process of FIG. 8 may be started in response to the power-on of the power receiving apparatus 103. Further, in the following description, an operation of the power receiving device 103-1 when the first power receiving device 103-1 enters the power transmission range 102 of the power transmission device 101 will be mainly described.

  In S801 of FIG. 8, the detection unit 218 of the power receiving apparatus 103-1 determines whether the power receiving apparatus 103-1 exists in the power transmission range 102 (within the predetermined range) of the power transmission apparatus 101. If the detection unit 218 determines that the power receiving apparatus 103-1 exists in the power transmission range 102 (YES in S801), the process proceeds to S802. In step S802, the power reception control unit 214 identifies the WPT method supported by the power transmission apparatus 101. Although a method of specifying the WPT method is not limited, for example, there is a method of transmitting a WPT related signal from the communication unit 213 of the power receiving device 103-1 to the power transmitting device 101. The power receiving apparatus 103-1 can specify the WPT method supported by the power transmission apparatus 101 based on the presence or absence of a response from the power transmission apparatus 101 to the WPT related signal and / or the content of the response.

  As an example of the WPT related signal, there are a connection request and a Ping signal defined in each of the first, second and third WPT methods. In addition, as another example of the WPT related signal, there is a message for inquiring the WPT method supported by the power transmission apparatus 101. The power transmitting apparatus 101 having received the message transmits the identification information of the WPT method supported by itself as a response message to the power receiving apparatus 103-1. When the identification of the WPT method supported by the power transmission apparatus 101 is completed, the process proceeds to step S803.

  In step S <b> 803, the power reception control unit 214 negotiates with the power transmission control unit 201 of the power transmission apparatus 101 regarding wireless power transmission. If there are a plurality of WPT methods supported by both the power transmitting apparatus 101 and the power receiving apparatus 103-1, the power reception control unit 214 determines the WPT method to be used for power transmission to the power receiving apparatus 103-1 before executing the negotiation. Do. Although the method of determining the WPT method is not particularly limited, for example, as described above, the power reception control unit 214 uses the WPT method capable of simultaneously transmitting power to more power reception devices as the WPT method using power transmission to the power reception device 103-1. It is possible to make a decision. Further, as another determination method, the power reception control unit 214 can determine the WPT method having a larger amount of transmittable power as the WPT method to be used for power transmission to the power receiving apparatus 103-1.

  The power reception control unit 214 determines a WPT method to be used for power transmission to the power reception device 103-1, and then performs negotiation with the power transmission device 101 according to the WPT method. In the negotiation in the present embodiment, the power transmission control unit 201 transmits control information such as the charge status (0% to 100%) of the power receiving device 103-1, required power (for example, 5 W), and current power consumption from the power receiving device 103-1. get. Then, the power transmission control unit 201 determines parameters such as a current value, a voltage value, and a driving frequency to be supplied to the power transmission antenna 206 based on the acquired various information related to the power receiving device 103-1. When the negotiation is completed, power transmission is started from the power transmission unit 205, and the power reception unit 211 of the power reception device 103 performs power reception (S804: power reception procedure).

  After the start of power reception, the detection unit 218 of the power reception device 103-1 determines whether a new power reception device (power reception device 103-N) is detected within the power transmission range 102 of the power transmission device 101 (S805: detection procedure) . If the detecting unit 218 detects a new power receiving apparatus 103 -N (YES in S805), the process advances to S807, and if not detected (NO in S805), the process advances to S806. In step S806, the power reception control unit 214 of the power reception device 103-1 determines whether to end the power reception from the power transmission device 101. If the power reception control unit 214 determines to end power reception from the power transmission apparatus 101 (YES in S806), the power reception control unit 214 performs power reception end processing in S810, and ends the processing in FIG. The termination condition of the power reception may be, for example, various errors of the power reception device 103-1, full charge of the power reception device 103-1, or a situation in which the power reception device 103-1 leaves the power transmission range 102.

  In step S807, the power reception control unit 214 specifies the WPT method supported by the other power reception apparatus 103-N. Although the method of specifying the WPT method is not particularly limited, for example, there is a method of transmitting a WPT related signal from the communication unit 213 of the power receiving device 103-1 to the power receiving device 103-N. The power reception control unit 214 of the power reception device 103-1 supports the WPT method supported by the power reception device 103-N based on the presence or absence of the response from the power reception device 103-N to the WPT related signal and / or the content of the response. It is possible to identify. Further, when the power reception control unit 214 determines that the power transmission device 101 supports a plurality of WPT methods among the WPT methods supported by the power reception device 103 -N, power transmission is performed to the power transmission device 101 by any WPT method. Decide what to do. Further, the power reception control unit 214 of the power reception device 103-1 obtains predetermined information such as the required power of the power reception device 103-N from the power reception device 103-N after determining the WPT method used for power reception from the power transmission device 101. Do. This information is used to determine whether to change the WPT method used by the power reception control unit 214 for power transmission to the power receiving apparatus 103-1. When the power reception control unit 214 acquires predetermined information from the power reception device 103-N, the process proceeds to step S808.

  In step S808, the power reception control unit 214 of the power reception device 103-1 receives the power reception device 103 based on the WPT method used for power transmission to the power reception device 103-N and the predetermined information acquired from the power reception device 103-N in step S807. It is determined whether to change the WPT method used for power transmission to -1. The determination method of the change of the WPT method in this embodiment is demonstrated using FIG. FIG. 9 is a flowchart for explaining the determination process (S808) as to whether or not to change the WPT method. As shown in Table 1, the power transmission apparatus 101 can transmit power of 5 W at maximum with the first WPT method, and can transmit power of 20 W at maximum with the second WPT method. The third WPT method Power transmission of up to 50W is possible.

  In step S901 in FIG. 9, the power reception control unit 214 determines whether power transmission to the power reception device 103 -N newly detected in step S805 is possible from the power transmission device 101. If power transmission can be performed according to the required power of the new power receiving apparatus 103-N without changing the WPT method (YES in S901), it is determined that the WPT method is not changed (S906), and the process proceeds to S809 in FIG. On the other hand, if it is not possible to transmit power to the new power receiving apparatus 103 -N unless the WPT method used for power transmission to the power receiving apparatus 103 being received is changed (NO in S901), the process proceeds to S902. This determination is performed based on whether power transmission to the power reception device 103 -N by the first WPT method exceeds the number of power reception devices that can transmit power by the first WPT method. In addition, this determination is performed based on whether or not power transmission to the power receiving apparatus 103 -N by the first WPT method exceeds the amount of power that can be transmitted by the first WPT method. Note that the power receiving device 103 that is receiving power is detected by the power transmitting device 101 before the power receiving device 103 -N is detected, and one or more power receiving devices that receive wireless power supply from the power transmitting device 101. It is The power receiving device 103-1 is included in the power receiving device 103 that is receiving power.

  In step S902, the power reception control unit 214 determines whether the power transmission apparatus 101 supports a WPT method other than the WPT method currently used. For example, when the power transmission device 101 is transmitting power to the power reception device 103-1 in the first WPT method, the power reception control unit 214 of the power reception device 103-1 may support the other WPT method. It is determined whether or not. When the power reception control unit 214 determines that the power transmission apparatus 101 does not support a WPT method other than the WPT method currently used (NO in S902), the power reception control unit 214 determines not to change the WPT method (S906). ), Proceed to S809 in FIG. On the other hand, when the power reception control unit 214 determines that the power transmission apparatus 101 supports the other WPT method (YES in S902), the process proceeds to S903.

  Even if the power reception control unit 214 of the power reception device 103-1 changes the WPT method used for power transmission to the power reception device 103 during power reception in S <b> 903, the power transmission device 101 follows the required power of the power reception device 103. It is determined whether power transmission is possible. For example, when the power transmitting apparatus 101 is transmitting power of 5 W to the power receiving apparatus 103-1 in the first WPT method, even if the WPT method is changed from the first WPT method to the second or third WPT method, It is determined whether power transmission of 5 W is possible for the power receiving device 103-1.

  In addition, the power reception control unit 214 receives power based on the number of power transmission possibilities for a plurality of power reception devices shown in Table 1 and the number of power reception devices 103 currently targeted by the power transmission device 101 to transmit power. It is determined whether it is possible to change the WPT method used for power transmission to the internal power receiving apparatus 103. For example, the power transmitting apparatus 101 transmits power to one power receiving apparatus 103-1 (supporting the first and second WPT systems) by the first WPT method, and three power receiving apparatuses 103-2 by the second WPT method. , 3 and 4, the power reception control unit 214 determines as follows. That is, when the WPT method used for power transmission to the power receiving apparatus 103-1 is changed, the power reception control unit 214 determines that power transmission according to the required power to the power receiving apparatus 103-1 can not be performed. However, there is a possibility that at least one of the power receiving apparatuses 103-2, 3 and 4 can be changed to the third WPT system. In such a case, the power reception control unit 214 of the power reception device 103-1 determines that power transmission can be performed according to the required power of the power reception device 103-1 even if the WPT method used for power transmission to the power reception device 103-1 is changed. Do.

  If the power reception control unit 214 determines that power transmission according to the required power to the power receiving device 103 can not be performed if the WPT method used for power transmission to the power receiving device 103 being received is changed (NO in S903), the WPT method is selected. It is determined not to change (S906), and the process proceeds to S809 in FIG. On the other hand, when the power reception control unit 214 determines that power transmission can be performed according to the required power to the power receiving device 103 even if the WPT method used for power transmission to the power receiving device 103 being received is changed (YES in S903) , S904. In step S904, if the power reception control unit 214 changes the WPT method used for power transmission to the power reception device 103 while receiving power, power transmission according to the required power of the new power reception device 103-N can be performed from the power transmission device 101. It is determined whether or not For example, when the power transmitting apparatus 101 is transmitting power of 5 W to the power receiving apparatus 103-1 in the first WPT method, and the required power of the new power receiving apparatus 103-N is 5 W, the power reception control unit 214 changes the WPT method. It is determined that power transmission to the new power receiving apparatus 103-N becomes possible. On the other hand, if the required power of the new power receiving apparatus 103-N is 10 W, the power reception control unit 214 determines that power transmission according to the required power of the new power receiving apparatus 103-N can not be performed even if the WPT method is changed. .

  When the power reception control unit 214 determines that power transmission according to the required power of the new power reception device 103-N can not be performed even if the WPT method used for power transmission to the power reception device 103 being received is changed (NO in S904 And the power reception control unit 214 determines not to change the WPT method (S906), and the process proceeds to S809 in FIG. On the other hand, if the power reception control unit 214 determines that power transmission can be performed according to the required power of the new power receiving device 103 -N by changing the WPT method used for power transmission to the power receiving device 103 while receiving power ( The processing advances to step S905. In step S905, the power reception control unit 214 determines to change the WPT method used for power transmission to the power reception device 103 which is receiving power, and the process proceeds to step S803 in FIG.

  According to the determination method described above, the power reception control unit 214 of the power reception device 103-1 performs the first WPT method when power is transmitted from the power transmission device 101 to the new power reception device 103-N according to the first WPT method. Determine whether the amount of power that can be transmitted is exceeded. The power reception control unit 214 determines whether the number of power transmission devices that can transmit power in the first WPT method exceeds the number of power reception devices that can transmit power in the first WPT method when power transmission is performed from the power transmission device 101 to the power reception device 103 -N. Do. Then, the power reception control unit 214 changes the WPT method used for power transmission to the power receiving device 103-1 (first power receiving device) from the first WPT method to the second WPT method according to the above determination result. Do. In the above description, although the case where the first WPT method is changed to the second WPT method is described, the present invention is not limited to this. For example, the second WPT method may be changed to the first WPT method, or the third WPT method may be changed to the second WPT method.

  Returning to FIG. 8, when the power reception control unit 214 of the power reception apparatus 103-1 determines that the WPT method is not changed in S808 (NO in S808), the power reception control unit 214 determines whether to end power reception (S809). If the power reception control unit 214 determines that the power reception is not ended (NO in S809), the power reception process is continued (S804). On the other hand, when it is determined that the power reception control unit 214 ends the power reception (YES in S809), the process proceeds to S810, performs the power reception end process, and ends the process of FIG.

  As described above, the power receiving apparatus 103 according to the present embodiment changes the WPT method used for power transmission to itself according to the WPT method supported by the power receiving apparatus 103 -N detected after itself. By doing this, it is possible to improve the efficiency of wireless power transmission in a system in which a plurality of wireless power transmission schemes (WPT schemes) are supported.

  In the above embodiment, the WPT method used for power transmission to the power receiving device 103-1 is different from the WPT method used for power transmission to the power receiving device 103-1 and the WPT method used for power transmission to the power receiving device 103-N. Although the description has been made centering on the modified example, the present invention is not limited to this example. That is, the power reception control unit 214 of the power reception device 103-1 receives power such that the WPT method used for power transmission to the power reception device 103-1 and the WPT method used for power transmission to the power reception device 103-N are the same. The WPT method used for power transmission to the device 103-1 can be changed.

  For example, when the power receiving apparatus 103-1 receives power from the power transmitting apparatus 101 in the first WPT method, the power receiving apparatus 103 -N does not support the first WPT method but transmits power in the second WPT method. There may be cases where it is determined to be within the transmission range 102 of the device 101. In this case, the power reception control unit 214 of the power reception device 103-1 changes the WPT method used for power transmission to the power reception device 103-1 from the first WPT method to the second WPT method. By doing this, the WPT method used for power transmission to the power receiving device 103-1 and the power receiving device 103-N can be unified to the second WPT method, so that wireless power transmission with high efficiency can be performed. Become.

Third Embodiment
In the first and second embodiments, the detection unit 209 of the power transmission device 101 or the detection unit 218 of the power reception device 103 determines whether the power reception device 103 exists in the power transmission range 102 of the power transmission device 101. Either 101 or the power receiving apparatus 103 has determined. Here, it may be determined whether the power receiving apparatus 103 exists in the power transmission range 102 of the power transmitting apparatus 101 in both the power transmitting apparatus 101 and the power receiving apparatus 103. That is, the determination results of both the power transmitting apparatus 101 and the power receiving apparatus 103 finally determine that the power receiving apparatus 103 is present only when the power receiving apparatus 103 is present. In this case, accuracy and reliability of detection of the power receiving device 103 in the power transmission device 101 and detection of the power transmission device 101 in the power receiving device 103 can be improved.

  As compared with the first and second embodiments, in the first embodiment, the power transmission device 101 starts the process for specifying the WPT method of the power reception device 103. In the second embodiment, the power receiving apparatus 103 starts processing for specifying the WPT method of the power receiving apparatus 103. On the other hand, either of the power transmission apparatus 101 or the power reception apparatus 103 may perform in the present embodiment. That is, either the power transmission apparatus 101 or the power reception apparatus 103 may start the process of specifying the WPT method and negotiation (S302 in FIG. 3 or S602 in FIG. 6) between the power transmission apparatus 101 and the power reception apparatus 103.

  Further, in the first embodiment, the power transmission apparatus 101 identifies the WPT method of the other power receiving apparatus 103, and in the second embodiment, the power receiving apparatus 103 identifies the WPT method of the other power receiving apparatus 103. On the other hand, either of the power transmission apparatus 101 or the power reception apparatus 103 may perform in the present embodiment. That is, the specification of the WPT method between the power transmission apparatus 101 and the other power reception apparatus 103 (S305 in FIG. 3) or the specification of the WPT method between the power reception apparatus 103 and the other power reception apparatus 103 (S605 in FIG. 6) Alternatively, any of the power receiving device 103 may be used.

Fourth Embodiment
In the first and second embodiments, the WPT method of power transmission is determined by a predetermined determination method regardless of the intention of the user of the power receiving apparatus 103 or another power receiving apparatus 103. The WPT method desired by the user may be directly set by the UI (user interface) 215 of the power reception device 103, and the set WPT method may be notified to the power transmission device 101. At that time, when the power transmission can not be performed by the notified WPT method, that effect may be displayed on the UI (user interface) 215. Similarly, the WPT method desired by the user may be directly set by the UI (user interface) 215 of another power receiving device 103, and the set WPT method may be notified to the power transmitting device 101 or the power receiving device 103. . At that time, when the power transmission can not be performed by the notified WPT method, the effect may be displayed on the UI (user interface) 215 of the other power receiving apparatus 103.

<Other Embodiments>
The present invention is also realized by executing the following processing. That is, software (program) for realizing the functions of the above-described embodiments is supplied to a system or apparatus via a network or various storage media, and a computer (or CPU, MPU or the like) of the system or apparatus reads the program. It is a process to execute.

101 Power Transmission Device 103 Power Receiving Device

Claims (12)

It is a power transmission device that transmits power wirelessly, and
Detection means for detecting a power receiving device;
Negotiation means for executing negotiation with the power receiving device for determining a parameter for wireless power transmission to the power receiving device detected by the detection means;
An identifying unit that identifies a wireless power transmission scheme supported by the power receiving apparatus detected by the detection unit among a plurality of wireless power transmission schemes having different transmittable power amounts before execution of the negotiation by the negotiation unit;
Power transmission means for wirelessly transmitting power to the power receiving device based on the parameter determined in the negotiation performed with the power receiving device by the negotiation means according to the wireless power transmission method specified by the specifying means When,
A power transmission device characterized by having.   The power transmission device according to claim 1, wherein the plurality of wireless power transmission methods have different frequencies used in wireless communication for controlling power transmission to the power reception device performed after completion of the negotiation.   When the power receiving device supports both the first wireless power transmission method supported by the power transmission device and the second wireless power transmission method having a transmittable power amount larger than the first wireless power transmission method, the power transmission unit The power transmission device according to claim 1, wherein power transmission is performed to the power reception device according to the second wireless power transmission system.   When the power receiving device supports two or more wireless power transmission methods among the plurality of wireless power transmission methods supported by the power transmission device, the power transmission unit is a wireless power transmission method with a larger amount of transmittable power. The power transmission device according to claim 1, wherein power transmission is performed to the power reception device.   Among the plurality of wireless power transmission methods supported by the power transmission device, when the power receiving device supports two or more wireless power transmission methods, the power transmission unit can transmit power to more power receiving devices The power transmission device according to claim 1 or 2, wherein power transmission is performed to the power reception device by a wireless power transmission method.   If the detection means detects the second power receiving device while transmitting power to the first power receiving device by the first wireless power transmission method, the first power reception according to the wireless power transmission method supported by the second power receiving device The power transmission device according to any one of claims 1 to 5, further comprising switching means for switching a wireless power transmission system to the device.   7. The apparatus according to any one of claims 1 to 6, further comprising changing means for changing a wireless power transmission method used to wirelessly transmit power to the power receiving device based on a notification from the power receiving device. Power transmission device as described. It has transmitting means for transmitting, to the power receiving device, information on the plurality of wireless power transmission methods supported by the power transmitting device in response to an inquiry from the power receiving device.
The power transmission device according to claim 7, wherein the change unit changes the wireless power transmission method according to reception of the notification from the power reception device after transmission of the information by the transmission unit. A power transmission control method executed by a power transmission apparatus that transmits power wirelessly, wherein
A detection step of detecting a power receiving device;
A negotiation step of executing a negotiation for determining a parameter for wireless power transmission to the power receiving device detected by the detection step with the power receiving device;
A specific step of specifying a wireless power transmission method supported by the power receiving apparatus detected in the detection step among a plurality of wireless power transmission methods having different transmittable power amounts before execution of the negotiation in the negotiation step;
Power is wirelessly transmitted to the power receiving device based on the parameter determined in the negotiation performed with the power receiving device in the negotiation step in accordance with the wireless power transmission method specified in the specifying step Power transmission control step of controlling the power transmission means;
A power transmission control method characterized by comprising:   The power transmission control method according to claim 9, wherein in the plurality of wireless power transmission methods, frequencies used in wireless communication for controlling power transmission to the power receiving device performed after completion of the negotiation are further different.   When the power receiving device supports both the first wireless power transmission method supported by the power transmission device and the second wireless power transmission method having a transmittable power amount larger than the first wireless power transmission method, the power transmission unit 11. The power transmission control method according to claim 9, wherein control is performed in the power transmission control step such that power is transmitted to the power receiving device by the second wireless power transmission scheme. A program for causing a computer to execute the power transmission control method according to any one of claims 9 to 11.

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