Charging device and charging method

Abstract

To provide a charging device and a charging method in which wireless charging can be properly performed.SOLUTION: A charging device according to the present disclosure includes a casing, a second coil, and a controller. The casing has a placement surface. An object to be charged can be placed on the placement surface. The object to be charged has a first coil. The second coil is housed in a position, in the casing, corresponding to the first coil. The controller obtains a parameter indicating the distance between the first coil and the second coil. In a case where the distance indicated by the parameter is less than a distance threshold, the controller capacitively couples the first coil and the second coil. In a case where the distance indicated by the parameter is greater than the distance threshold, the controller resonantly couples the first coil and the second coil.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a charging device and a charging method. [Background technology]

[0002] In a charging device capable of wireless charging, when an object to be charged is placed on the placement surface of the housing, power is sent in the form of electromagnetic energy or the like from a coil in the housing to a coil in the object to be charged. This allows the charging device to wirelessly charge the object to be charged. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-288429 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the charging device, depending on the distance between the coil in the housing and the coil in the object to be charged, the power sent from the coil in the housing to the coil in the object to be charged may be weaker than the permitted power. This may make it difficult for the charging device to properly wirelessly charge the object to be charged.

[0005] The present disclosure provides a charging device and a charging method that can appropriately perform wireless charging. [Means for solving the problem]

[0006] A charging device according to the present disclosure includes a housing, a second coil, and a controller. The housing has a placement surface. An object to be charged can be placed on the placement surface. The object to be charged has a first coil. The second coil is accommodated in a position corresponding to the first coil in the housing. The controller acquires a parameter indicating a distance between the first coil and the second coil. If the distance indicated by the parameter is below a distance threshold, the controller inductively couples the first coil and the second coil. If the distance indicated by the parameter exceeds the distance threshold, the controller resonantly couples the first coil and the second coil. Effect of the Invention

[0007] According to the charging device of the present disclosure, wireless charging can be performed appropriately. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing an example of an external configuration of a charging device according to an embodiment. [Diagram 2] FIG. 4 is a diagram showing another example of the external configuration of the charging device according to the embodiment. [Diagram 3] FIG. 1 is a diagram showing a configuration of a charging device according to an embodiment. [Figure 4] FIG. 4 is a sequence diagram showing a communication procedure of the charging device according to the embodiment. [Diagram 5] FIG. 4 is a sequence diagram showing a communication procedure in a ping phase according to the embodiment. [Figure 6] 4 is a flowchart showing the operation of the charging device according to the embodiment. [Figure 7] 6 is a flowchart showing the operation of a charging device according to a first modified example of an embodiment. [Figure 8] 10 is a flowchart showing the operation of a charging device according to a second modified example of an embodiment. [Figure 9] 10 is a flowchart showing the operation of a charging device according to a third modified example of an embodiment. [Figure 10] 10 is a flowchart showing the operation of a charging device according to a fourth modified example of an embodiment. [Figure 11]FIG. 13 is a diagram showing a data structure of setting information according to a fourth modified example of the embodiment. [Figure 12] FIG. 13 is a diagram showing an example of a schematic configuration of a charging system according to a fifth modified example of an embodiment. [Figure 13] FIG. 13 is a diagram showing an example of a configuration related to power transmission of a charging system according to a fifth modified example of an embodiment. [Figure 14] FIG. 13 is a diagram showing an example of the configuration of a controller according to a fifth modified example of an embodiment. [Figure 15] 13 is a flowchart showing an example of the flow of a control process executed by a charging device in a fifth modified example of an embodiment. [Figure 16] 13 is a flowchart showing an example of the flow of a fine adjustment process based on control of a resonance capacitor in a fifth modified example of the embodiment. [Figure 17] 13 is a flowchart showing an example of the flow of fine adjustment processing based on a change in the relative position of the coils in the fifth modified example of the embodiment. [Figure 18] 13 is a flowchart showing the operation of a charging device according to a ninth modified example of an embodiment. [Figure 19] 23 is a flowchart showing the operation of a charging device according to a tenth modified example of an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of a charging device according to the present disclosure will be described with reference to the drawings.

[0010] (Embodiment) The charging device in the embodiment is capable of wireless charging, and when an object to be charged is placed on the placement surface of the housing, power is sent in the form of electromagnetic energy or the like from a coil inside the housing to a coil inside the object to be charged, and measures are taken to ensure proper wireless charging.

[0011] The charging device 1 may be configured as shown in Fig. 1 or Fig. 2. Fig. 1 is a diagram showing an example of the external configuration of the charging device 1, exemplifying the external configuration when the charging device 1 is a horizontal type. Fig. 2 is a diagram showing another example of the external configuration of the charging device 1, exemplifying the external configuration when the charging device 1 is a vertical type.

[0012] The object to be charged 100 may be an electronic device having a display such as a smartphone terminal, a tablet terminal, or a smart watch, or may be an electronic device without a display such as a wireless earphone, a wireless speaker, or a wireless mouse. The object to be charged 100 may have a flat box shape. Accordingly, the charging device 1 may have a box shape.

[0013] The charging device 1 has a wireless charging function, and an object to be charged 100 compatible with the wireless charging function can be placed on the placement surface 2a of the charging device 1. Figs. 1 and 2 show an example of a state in which the object to be charged 100 is placed on the placement surface 2a. The charging device 1 has a housing 2 and a power transmission coil 3. In the charging device 1, the power transmission coil 3 is placed in the housing 2 near the placement surface 2a. In the following, the longitudinal direction of the housing 2 is defined as the X direction, the lateral direction of the housing 2 is defined as the Y direction, and the direction perpendicular to the X direction and the Y direction is defined as the Z direction.

[0014] In this specification, the positive direction of the Z axis may be expressed as "upward," "upper side," or "upper surface side." Similarly, the negative direction of the Z axis may be expressed as "downward," "lower side," or "lower surface side." Furthermore, the plane and the direction within the plane spanned by the X and Y axes may be expressed as the "horizontal plane" and the "horizontal direction," respectively.

[0015] In this specification, "parallel," "horizontal," "vertical," and "orthogonal" do not only mean completely parallel, horizontal, vertical, and orthogonal, but also mean deviations from parallel, horizontal, vertical, and orthogonal within a margin of error. Furthermore, "approximately" means roughly the same.

[0016] The object to be charged 100 has a housing 102 and a receiving coil 103. The housing 102 has a front surface 102a and a rear surface 102b. The object to be charged 100 has a display structure (not shown) near the front surface 100a, and the receiving coil 103 is disposed near the rear surface 102b inside the housing 102. The charging device 1 may have a moving-type wireless charging function, and the transmitting coil 3 may be configured to be movable in the XY directions inside the housing 2. As shown in Figs. 1 and 2, the charging device 1 may be capable of efficient wireless charging by moving the transmitting coil 3 in the XY directions so that the XY positions of the transmitting coil 3 match the XY positions of the receiving coil 103.

[0017] It is possible to use electromagnetic induction wireless charging as the wireless charging of the charging device 1. In electromagnetic induction wireless charging, the power transmitting coil 3 and the power receiving coil 103 are inductively coupled, and power is sent from the power transmitting coil 3 to the power receiving coil 103 in the form of electromagnetic energy or the like.

[0018] In the charging device 1, the distance d in the Z direction between the power transmitting coil 3 and the power receiving coil 103 may become large.

[0019] For example, when the charging device 1 is of a horizontal type, gravity acts in the -Z direction and tends to press the object to be charged 100 against the placement surface 2a. As shown in Fig. 1, the object to be charged 100 may have a convex structure 102b1 such as a camera lens on the back surface 102b. In this case, when the object to be charged 100 is placed on the placement surface 2a, the Z-direction distance d between the transmitting coil 3 and the receiving coil 103 increases by the Z thickness of the convex structure 102b1 from the expected distance.

[0020] Alternatively, when the charging device 1 is of a vertical type, gravity acts in the -Y direction, making it difficult to press the object to be charged 100 against the placement surface 2a. As shown in Fig. 2, the object to be charged 100 can be placed so that its housing 102 is spaced apart in the Z direction from the housing 2 of the charging device 1. In this case, when the object to be charged 100 is placed on the placement surface 2a, the Z-directional distance d between the power transmitting coil 3 and the power receiving coil 103 increases by the amount of the clearance between the housings 2 and 102, compared to the planned distance.

[0021] In the case of electromagnetic induction type wireless charging, when the Z-direction distance d between the power transmitting coil 3 and the power receiving coil 103 becomes large, the power transmitted from the power transmitting coil 3 to the power receiving coil 103 becomes weaker than the allowable power, and the charging time may become longer or automatic charging may not start. This may make it difficult for the charging device 1 to appropriately perform wireless charging on the object to be charged 100.

[0022] On the other hand, there is a magnetic resonance method in which a pair of coils are resonantly coupled to transmit power in the form of electromagnetic energy from one coil to the other coil. The magnetic resonance method is also called the magnetic resonance method. If the magnetic resonance method is applied to wireless charging of the charging device 1, it is expected that appropriate charging will be possible even if the Z-direction distance d between the power transmitting coil 3 and the power receiving coil 103 is long.

[0023] Therefore, the charging device 1 acquires a parameter indicating the Z-direction distance d between the transmitting coil 3 and the receiving coil 103, and switches the wireless charging method between the electromagnetic induction method and the magnetic field resonance method depending on the Z-direction distance d indicated by the parameter, thereby optimizing wireless charging over a wide distance range.

[0024] 3, the charging device 1 has a DC power supply 11, a DC-DC converter circuit 12, an inverter circuit 13, a voltage detection circuit 14, a voltage detection circuit 15, a drive frequency control circuit 5, a capacitor 4, a signal demodulation circuit 16, a position detection pattern coil 19, a position detection circuit 20, a transmitting coil moving mechanism 6, and a controller 17 in addition to the case 2 and the transmitting coil 3. The object to be charged 100 has a capacitor 104, a receiving circuit 105, and a load 106 in addition to the case 102 and the receiving coil 103. FIG. 3 is a diagram showing the configuration of the charging device 1.

[0025] In the charging device 1, a controller 17 comprehensively controls each part of the charging device 1.

[0026] For example, the controller 17 acquires a parameter Pd indicating a distance d in the Z direction between the power transmitting coil 3 and the power receiving coil 103. When the Z direction distance d indicated by the parameter Pd is below a distance threshold THpd, the controller 17 inductively couples the power transmitting coil 3 and the power receiving coil 103 so that wireless charging is performed by an electromagnetic induction method. When the Z direction distance d indicated by the parameter Pd exceeds the distance threshold THpd, the controller 17 resonantly couples the power transmitting coil 3 and the power receiving coil 103 so that wireless charging is performed by a magnetic field resonance method.

[0027] Here, a coupling coefficient k between the power transmitting coil 3 and the power receiving coil 103 may be used as a parameter Pd indicating the Z-direction distance d between the power transmitting coil 3 and the power receiving coil 103. The coupling coefficient k indicates the degree of inductive coupling between the power transmitting coil 3 and the power receiving coil 103, and takes a value between 0 and 1. The coupling coefficient k can be defined by the following Equation 1.

number

[0028] In the formula 1, L3 represents the self-inductance of the power transmitting coil 3. 103 indicates the self-inductance of the receiving coil 103. 3_103 indicates the mutual inductance between the power transmitting coil 3 and the power receiving coil 103. The coupling coefficient k is correlated with the Z-direction distance d between the power transmitting coil 3 and the power receiving coil 103. The value of the coupling coefficient k tends to be smaller as the Z-direction distance d between the power transmitting coil 3 and the power receiving coil 103 increases.

[0029] The controller 17 may obtain the coupling coefficient k by calculating the coupling coefficient k as described below. When the coupling coefficient k exceeds a coefficient threshold THk, the controller 17 may inductively couple the power transmitting coil 3 and the power receiving coil 103 to perform wireless charging by an electromagnetic induction method. The coefficient threshold THk corresponds to a distance threshold THpd. When the coupling coefficient k is below the coefficient threshold THk, the controller 17 may resonantly couple the power transmitting coil 3 and the power receiving coil 103 to perform wireless charging by a magnetic field resonance method.

[0030] The DC power supply 11 generates a DC power supply voltage Vdc1. The DC power supply 11 may be, for example, a battery, a power supply circuit that receives a DC power supply voltage from an external source, or a power supply circuit that receives an AC power supply voltage from an external source and converts it into a DC power supply voltage. The DC power supply 11 supplies the DC power supply voltage Vdc1 to the DC-DC converter circuit 12.

[0031] The DC-DC converter circuit 12 converts the DC power supply voltage Vdc1 into the DC voltage Vdc2 under the control of the controller 17. The DC-DC converter circuit 12 may step up the DC power supply voltage Vdc1 and convert it into the DC voltage Vdc2, or may step down the DC power supply voltage Vdc1 and convert it into the DC voltage Vdc2, or may convert the DC power supply voltage Vdc1 into the DC voltage Vdc2 while adjusting the waveform while keeping it at a constant voltage. The DC-DC converter circuit 12 supplies the DC voltage Vdc2 to the inverter circuit 13.

[0032] The drive frequency control circuit 5 generates a control signal for controlling the drive frequency of the inverter circuit 13 under the control of the controller 17. If the inverter circuit 13 has a switching element, the control signal may be a switching control signal for turning the switching element on and off at a period corresponding to the drive frequency. The drive frequency control circuit 5 supplies the control signal to the inverter circuit 13.

[0033] For example, when the Z-direction distance d indicated by the parameter Pd falls below the distance threshold THpd, the controller 17 controls the drive frequency of the inverter circuit 13 to a predetermined frequency fc. The predetermined frequency fc may be experimentally determined in advance as a frequency suitable for the electromagnetic induction method and may be fixedly set in the controller 17. When the coupling coefficient k exceeds the coefficient threshold THk, the controller 17 may control the drive frequency of the inverter circuit 13 to the predetermined frequency fc. In response to the control of the controller 17, the drive frequency control circuit 5 generates a control signal for controlling the drive frequency to the predetermined frequency fc and supplies it to the inverter circuit 13. This allows the controller 17 to perform wireless charging by the electromagnetic induction method.

[0034] When the Z-direction distance d indicated by the parameter Pd exceeds the distance threshold THpd, the controller 17 controls the drive frequency of the inverter circuit 13 to the resonance frequency fr. When the coupling coefficient k is below the coefficient threshold THk, the controller 17 may control the drive frequency of the inverter circuit 13 to the resonance frequency fr. The resonance frequency fr is the resonance frequency of the resonance circuit formed by the receiving coil 103 and the capacitor 104 in the object to be charged 100. The controller 17 may obtain the resonance frequency fr using the inductance design value of the receiving coil 103 and the capacitance design value of the capacitor 104. The drive frequency control circuit 5 generates a control signal for controlling the drive frequency to the resonance frequency fr and supplies it to the inverter circuit 13 according to the control of the controller 17. This allows the controller 17 to perform wireless charging by the magnetic field resonance method.

[0035] The inverter circuit 13 operates at a drive frequency indicated by the control signal, and converts the DC voltage Vdc2 into a single-phase AC voltage Vac1. The inverter circuit 13 may have a switching element, and may convert the DC voltage Vdc2 into the single-phase AC voltage Vac1 by turning the switching element on and off at a cycle corresponding to the drive frequency. The inverter circuit 13 can supply the single-phase AC voltage Vac1 to the power transmitting coil 3 via the capacitor 4. This allows the inverter circuit 13 to drive the power transmitting coil 3 via the capacitor 4.

[0036] The capacitor 4 is connected between the inverter circuit 13 and the power transmitting coil 3. One end of the capacitor 4 is connected to the P-side output node of the inverter circuit 13, and the other end is connected to the power transmitting coil 3. The capacitor 4 receives a single-phase AC voltage Vac1 from the inverter circuit 13 and transmits it to the power transmitting coil 3. By providing the capacitor 4 between the inverter circuit 13 and the power transmitting coil 3, the AC voltage Vac1 can be smoothed, and the efficiency and stability of wireless charging can be improved.

[0037] The power transmitting coil 3 is connected between the capacitor 4 and the inverter circuit 13. One end of the power transmitting coil 3 is connected to the capacitor 4, and the other end is connected to an N-side output node of the inverter circuit 13.

[0038] The voltage detection circuit 14 detects the voltage Vin on the input side of the inverter circuit 13. A detection node of the voltage detection circuit 14 is connected to a line connecting the DC-DC converter circuit 12 and the inverter circuit 13. The voltage detection circuit 14 may detect the voltage Vin on the input side of the inverter circuit 13 via the detection node. The voltage detection circuit 14 supplies the detected voltage Vin to the controller 17. This allows the controller 17 to calculate the coupling coefficient k using the voltage Vin.

[0039] The voltage detection circuit 15 detects the voltage V CTX_PPThe voltage detection circuit 15 has a detection node connected to a line connecting the inverter circuit 13 and the capacitor 4. The voltage detection circuit 15 detects the maximum amplitude voltage of the AC voltage Vac on the output side of the inverter circuit 13 via the detection node as a voltage V CTX_PP The voltage detection circuit 15 may detect the detected voltage V CTX_PP to the controller 17. As a result, the controller 17 supplies the voltage V CTX_PP The coupling coefficient k can be calculated using

[0040] The controller 17 can communicate with the object to be charged 100 .

[0041] For example, the controller 17 may transmit information to the object to be charged 100 via the drive frequency control circuit 5, the inverter circuit 13, and the power transmitting coil 3. The controller 17 frequency-modulates the drive frequency according to the information, and transmits an AC signal including a modulated component to the object to be charged 100. When the object to be charged 100 receives the AC signal at the power receiving coil 103, the power receiving circuit 105 extracts the modulated component from the AC signal and restores the information. The object to be charged 100 may perform an operation according to the restored information.

[0042] The controller 17 may transmit the information to the object to be charged 100 via the DC-DC converter circuit 12, the inverter circuit 13, and the transmitting coil 3. The controller 17 amplitude-modulates the amplitude of the DC voltage Vdc2 in accordance with the information, and transmits an AC signal including a modulated component to the object to be charged 100. When the object to be charged 100 receives the AC signal at the receiving coil 103, the receiving circuit 105 extracts the modulated component from the AC signal and restores the information. The object to be charged 100 may perform an operation according to the restored information.

[0043] It should be noted that the controller 17 may transmit information using a modulation method other than frequency modulation and amplitude modulation.

[0044] Furthermore, the controller 17 may receive information from the object to be charged 100 via the power transmitting coil 3 and the signal demodulation circuit 16. When an AC signal is received from the object to be charged 100, the signal demodulation circuit 16 extracts a modulated component from the AC signal to restore the information. The signal demodulation circuit 16 may restore the information by a frequency modulation method, an amplitude modulation method, or another modulation method. The signal demodulation circuit 16 supplies the restored information to the controller 17.

[0045] The position detection pattern coil 19 is disposed between the power transmission coil 3 and the arrangement surface 2a (see FIGS. 1 and 2). The position detection pattern coil 19 includes a plurality of coils distributed in the X and Y directions.

[0046] The position detection circuit 20 is connected between the position detection pattern coil 19 and the controller 17. The position detection circuit 20 is connected to each of the multiple coils of the position detection pattern coil 19. The position detection circuit 20 is capable of detecting the XY position of the power receiving coil 103 under the control of the controller 17.

[0047] The controller 17 may detect the XY position of the receiving coil 103 in the object to be charged 100 using the position detection circuit 20 and the position detection pattern coil 19. The position detection circuit 20 supplies a pulse to each of the multiple coils of the position detection pattern coil 19 in response to the control of the controller 17. Each of the multiple coils generates a magnetic flux corresponding to the pulse. When the multiple coils receive magnetic flux as an echo from the receiving coil 103, they generate an induced current corresponding to the magnetic flux and return it to the position detection circuit 20. The position detection circuit 20 specifies the XY position of the receiving coil 103 in response to the induced current of each of the multiple coils. The position detection circuit 20 supplies the specified XY position to the controller 17.

[0048] The power transmitting coil moving mechanism 6 is capable of moving the power transmitting coil 3 in the X and Y directions under the control of a controller 17.

[0049] The controller 17 may use the power transmitting coil moving mechanism 6 to move the power transmitting coil 3 in the X and Y directions in accordance with the X and Y positions of the power receiving coil 103 detected by the position detection circuit 20. The power transmitting coil moving mechanism 6 moves the power transmitting coil 3 in the X and Y directions in accordance with the control of the controller 17 so as to approach the X and Y positions of the power receiving coil 103. This allows the X and Y positions of the power transmitting coil 3 to be aligned so as to match the X and Y positions of the power receiving coil 103.

[0050] In the object to be charged 100, the receiving coil 103 is connected between the capacitor 104 and the receiving circuit 105. The transmitting coil 3 has one end connected to the capacitor 104 and the other end connected to an input node of the receiving circuit 105.

[0051] Capacitor 104 is connected between power receiving coil 103 and power receiving circuit 105. One end of capacitor 104 is connected to power receiving coil 103, and the other end is connected to an N-side input node of power receiving circuit 105. Capacitor 104 receives power supply voltage Vac2 from power receiving coil 103 and transmits it to power receiving circuit 105.

[0052] The power receiving circuit 105 generates a charging current according to the induced electromotive force generated in the power receiving coil 103 .

[0053] The load 106 is, for example, a battery, and is charged by the output current of the power receiving circuit 105 .

[0054] In the charging device 1, the controller 17 functionally includes a coupling coefficient calculation unit 171, a judgment unit 172, and a drive frequency determination unit 173. Each unit in the controller 17 may be realized in software as a module configured in the controller 17 by executing software. For example, the controller 17 may be a system including a processor, a nonvolatile memory, and a volatile memory. The nonvolatile memory stores a program. The processor may read and start the program from the nonvolatile memory when the power supply of the charging device 1 is turned on as a trigger, and may expand the modules corresponding to each unit into the volatile memory collectively at the time of compilation or sequentially as the processing progresses. In this way, the processor may operate according to the program. Alternatively, each unit in the controller 17 may be realized in hardware as a circuit configured in the controller 17. Alternatively, some of the units in the controller 17 may be realized in software and the rest may be realized in hardware.

[0055] The coupling coefficient calculation unit 171 receives the voltage Vin from the voltage detection circuit 14 and the voltage V CTX_PP The coupling coefficient calculation unit 171 receives the voltage Vin and the voltage V CTX_PP The coupling coefficient calculation unit 171 may calculate an approximation of the value of the coupling coefficient by using the following Equation 2 and Equation 3.

number

number

[0056] In Equation 2, E0 corresponds to the output voltage of the charging device 1, and is a parameter specific to the circuit characteristics of the charging device 1 and the object to be charged 100. E1 corresponds to the input voltage of the charging device 1, and is a parameter specific to the circuit characteristics of the charging device 1 and the object to be charged 100. E0 and E1 can each be obtained in advance by calibration or the like and set in the controller 17. p is obtained by Equation 3.

[0057] In Equation 3, Vrect is the voltage reported by the object to be charged 100 through communication. Vin is the voltage detected by the voltage detection circuit 14. CTX_PP is the voltage detected by the voltage detection circuit 15.

[0058] The coupling coefficient calculation unit 171 supplies the calculated coupling coefficient k to the determination unit 172 .

[0059] The determination unit 172 may determine whether the object to be charged 100 is located at a location farther away than the distance threshold THpd from the value of the coupling coefficient k, using a coefficient threshold THk. The coefficient threshold THk may be experimentally determined in advance as a Z-direction distance at which power can be transmitted by the electromagnetic induction method. The coefficient threshold THk may be, for example, 0.2 to 0.7.

[0060] The determination unit 172 compares the coupling coefficient k with the coefficient threshold THk, and if the coupling coefficient k exceeds the coefficient threshold THk, determines that the object to be charged 100 is not farther than the distance threshold THpd. If the coupling coefficient k is below the coefficient threshold THk, the determination unit 172 determines that the object to be charged 100 is farther than the distance threshold THpd. The determination unit 172 supplies the determination result to the drive frequency determination unit 173.

[0061] The drive frequency determination unit 173 determines the drive frequency of the inverter circuit 13 according to the determination result of the determination unit 172. When the object to be charged 100 is not farther away than the distance threshold THpd, the drive frequency determination unit 173 determines the drive frequency of the inverter circuit 13 to be a predetermined frequency fc. When the object to be charged 100 is farther away than the distance threshold THpd, the drive frequency determination unit 173 determines the drive frequency of the inverter circuit 13 to be a resonance frequency fr of the power receiving coil 103 and the capacitor 104. The drive frequency determination unit 173 may determine the frequency fr by the following formula 4.

number

[0062] In Equation 4, k is the coupling coefficient. 103 is a design value of the self-inductance of the power receiving coil 103, and can be set in advance in the controller 17. 104 is a design value of the capacitance of the capacitor 104 and can be set in advance in the controller 17.

[0063] The controller 17 controls the drive frequency of the inverter circuit 13 to the determined frequency via the drive frequency control circuit 5 .

[0064] Next, a communication procedure of the charging device 1 will be described with reference to Fig. 4. Fig. 4 is a sequence diagram showing a communication procedure of the charging device.

[0065] When the object to be charged 100 is placed on the placement surface 2a of the charging device 1, the charging device 1 executes a process of the ping phase (SC10).

[0066] In the ping phase (SC10), SC11 to SC15 shown in Fig. 5 are carried out. Fig. 5 is a sequence diagram showing the communication procedure in the ping phase (SC10).

[0067] In the charging device 1, the controller 17 transmits an analog ping (SC11), transmits a predetermined protection request (Protection) (SC12), and then transmits an object detection request (Object Detection) (SC13). The controller 17 may perform the processes of SC11 to SC13 using the position detection circuit 20 and the position detection pattern coil 19. The controller 17 waits until there is a response to SC11 to SC13 in order to detect whether or not an object exists within a communication range (Examine Operating Volume).

[0068] When the controller 17 receives responses to SC11 to SC13, it determines that the presence of the object to be charged 100 has been detected, and transmits a digital ping including a wake-up request (Wake Up Power Receiver) to the object to be charged 100 (SC14).

[0069] In response to this, the object to be charged 100 transmits the signal strength data SIG or the end power data EPT to the charging device 1 as a response to SC14 in order to indicate its own presence (Indicate Presence).

[0070] In the charging device 1, when the controller 17 receives the signal strength data SIG or the end power data EPT, it determines that the ping phase (SC10) is completed and executes processing of the configuration phase (SC20).

[0071] In the configuration phase (SC20), the controller 17 transmits a configuration information request to the object to be charged 100, and receives the configuration information from the object to be charged 100 as a response thereto.

[0072] At this time, the controller 17 may calculate the coupling coefficient k according to Equation 3 using the voltage Vrect included in the configuration information.

[0073] When the configuration information is received, the controller 17 determines that the configuration phase (SC20) is completed, and executes processing of the negotiation phase (SC30).

[0074] In the negotiation phase (SC30), the controller 17 transmits power contract information including a transmittable power level to the charge target 100, and then receives a power contract request including a power level calculated by taking into account the transmittable power level and the receivable power level from the charge target 100. In this way, the controller 17 negotiates the power contract.

[0075] When the controller 17 receives the power contract request, it determines that the negotiation phase (SC30) is completed, and executes the processing of the power transmission phase (SC40).

[0076] In the power transmission phase (SC40), the controller 17 transmits power to the object to be charged 100 in accordance with the power contract.

[0077] At this time, when the coupling coefficient k exceeds the coefficient threshold THk, the controller 17 inductively couples the power transmitting coil 3 and the power receiving coil 103 so that wireless charging is performed by the electromagnetic induction method. When the coupling coefficient k is below the coefficient threshold THk, the controller 17 resonantly couples the power transmitting coil 3 and the power receiving coil 103 so that wireless charging is performed by the magnetic field resonance method.

[0078] Next, the operation of the charging device 1 will be described with reference to Fig. 6. Fig. 6 is a flowchart showing the operation of the charging device 1. Fig. 6 illustrates an example of the operation of the charging device 1 when the charging device 1 has, as operation modes, an induction mode corresponding to an electromagnetic induction method and a resonance mode corresponding to a magnetic field resonance method.

[0079] In the default state, the operation mode of the charging device 1 is set to the induction mode. When the object to be charged 100 is placed on the placement surface 2a and the presence of the object to be charged 100 is detected, the controller 17 executes a digital ping (S1). The controller 17 transmits the digital ping to the object to be charged 100. In response, when the controller 17 receives the signal strength data SIG or the end power data EPT from the object to be charged 100, it transmits a configuration information request to the object to be charged 100.

[0080] In response to this, when the controller 17 receives the configuration information from the object to be charged 100, the controller 17 calculates the coupling coefficient k by Equation 3 using the voltage Vrect included in the configuration information (S2).

[0081] The controller 17 determines whether the object to be charged 100 is located away from the object to be charged 100 by a distance threshold value THpd or not, depending on the coupling coefficient k calculated in S2 (S3).

[0082] If the coupling coefficient k exceeds the coefficient threshold THk, the controller 17 determines that the object to be charged 100 is not farther away than the distance threshold THpd (No in S3), and maintains the induction mode (S4). The controller 17 performs wireless charging in the induction mode (S5). That is, the controller 17 controls the operating frequency of the inverter circuit 13 to a predetermined frequency fc, and drives the power transmitting coil 3 at the predetermined frequency fc. As a result, the controller 17 inductively couples the power transmitting coil 3 and the power receiving coil 103, and transmits power from the power transmitting coil 3 to the power receiving coil 103 by electromagnetic induction.

[0083] If the coupling coefficient k is less than the coefficient threshold THk, the controller 17 determines that the object to be charged 100 is farther away than the distance threshold THpd (Yes in S3), and changes the operation mode from the induction mode to the resonance mode (S6). 103 and the capacitance design value C of the capacitor 104 104 The resonance frequency fr is calculated by using the formula 4 (S7).

[0084] The controller 17 changes the operating frequency of the inverter circuit 13 from a predetermined frequency fc to a resonant frequency fr (S8) and performs wireless charging in a resonant mode (S9). That is, the controller 17 controls the operating frequency of the inverter circuit 13 to the resonant frequency fr and drives the power transmitting coil 3 at the resonant frequency fr. As a result, the controller 17 resonantly couples the power transmitting coil 3 and the power receiving coil 103 and transmits power from the power transmitting coil 3 to the power receiving coil 103 by an electric field resonance method.

[0085] When wireless charging in the resonant mode (S9) is completed, the controller 17 changes the operation mode back from the resonant mode to the inductive mode (S10).

[0086] As described above, in the embodiment, in the charging device 1, the controller 17 acquires the parameter Pd indicating the Z direction distance d between the power transmitting coil 3 and the power receiving coil 103, and switches the wireless charging method between the electromagnetic induction method and the magnetic field resonance method according to the Z direction distance d indicated by the parameter Pd. This enables the charging device 1 to optimize wireless charging over a wide distance range.

[0087] The concept of this embodiment may be applied to a charging device 1 having a wireless charging function other than that of the moving type.

[0088] For example, a charging device with a multi-coil wireless charging function has multiple power transmitting coils that are distributed in the XY directions and are fixed, and changes which of the multiple power transmitting coils to energize depending on the XY position of the power receiving coil in the object to be charged. In this charging device, the controller also acquires a parameter Pd indicating the Z direction distance d between the power transmitting coil 3 and the power receiving coil 103, and switches the wireless charging method between the electromagnetic induction method and the magnetic field resonance method depending on the Z direction distance d indicated by the parameter Pd, thereby optimizing wireless charging over a wide distance range.

[0089] (First Modification) In addition, as a first modified example of the embodiment, the controller 17 may calculate the resonant frequency fr using the measured inductance value of the receiving coil 103 and the measured capacitance value of the capacitor 104 instead of the designed inductance value of the receiving coil 103 and the designed capacitance value of the capacitor 104.

[0090] For example, when the object to be charged 100 is manufactured, the inductance of the receiving coil 103 and the capacitance of the capacitor 104 may be measured and stored as the measured inductance value of the receiving coil 103 and the measured capacitance value of the capacitor 104, respectively, included in the configuration information.

[0091] In this case, in the configuration phase (SC20) shown in FIG. 4, when the controller 17 receives configuration information from the object to be charged 100, the controller 17 reads the inductance measurement value L of the receiving coil 103 included in the configuration information. 103 ' and the capacitance measurement C of the capacitor 104 104 The resonance frequency fr may be calculated by the following formula 5 using the above formula.

number

[0092] Formula 5 is the L in Formula 4 103 and C 104 are L 103 ' and C 104 ' has been replaced with '.

[0093] The charging device 1 may perform the operation shown in Fig. 7 instead of Fig. 6. Fig. 7 is a flowchart showing the operation of the charging device 1 according to the first modified example of the embodiment.

[0094] After steps S1 to S6 are performed in the same manner as in the embodiment, the controller 17 receives the inductance measurement value L of the power receiving coil 103 included in the configuration information received in S2. 103 ' and the capacitance measurement C of the capacitor 104 104 Using the above, the resonance frequency fr is calculated by Equation 5 (S11). After that, steps S8 to SI0 are performed in the same manner as in the embodiment.

[0095] This makes it possible to more accurately determine the resonance frequency fr, and to perform wireless charging with even higher efficiency when switching to the magnetic field resonance method.

[0096] As a second modification of the embodiment, the charging device 1 may perform an operation taking into consideration the standard.

[0097] For example, the Qi2 standard established by the Wireless Power Consortium (WPC) prescribes the Magnetic Power Profile (MPP) as a wireless charging function in addition to the Baseline Power Profile (BPP) and Extended Power Profile (EPP).

[0098] BPP supports low-speed wireless charging and transmits power at a slow rate with relatively low power. EPP supports high-speed wireless charging and transmits power at a fast rate with relatively high power. MPP supports even faster wireless charging and uses magnets to align the transmitting coil and receiving coil, transmitting power at a fast rate with relatively high power when aligned with high precision.

[0099] (Second Modification) The charging device 1 may perform the operation shown in Fig. 8 instead of Fig. 6. Fig. 8 is a flowchart showing the operation of the charging device 1 according to the second modified example of the embodiment.

[0100] If the object to be charged 100 is compatible with the EPP, configuration information including information indicating that the object to be charged is compatible with the EPP may be stored in advance at the time of manufacture. If the object to be charged 100 is provided with a magnet 107 (not shown) whose XY position relative to the receiving coil 103 is fixed, the object to be charged 100 is compatible with the MPP, and configuration information further including information indicating that the object to be charged is compatible with the MPP may be stored in advance at the time of manufacture. If the object to be charged 100 is not provided with the magnet 107, the object to be charged 100 is not compatible with the MPP, and configuration information not including information indicating that the object to be charged is compatible with the MPP may be stored in advance at the time of manufacture.

[0101] When a magnet 7 (not shown) whose XY position relative to the power transmitting coil 3 is fixed is provided, the charging device 1 supports MPP, and therefore sets the charging mode indicating the wireless charging function to MPP.

[0102] After S1 is performed in the same manner as in the embodiment, when the controller 17 receives configuration information from the object to be charged 100 in response to the digital ping, the controller 17 uses the information on the wireless charging function included in the configuration information to determine whether the object to be charged 100 supports MPP (S21).

[0103] If the object to be charged 100 does not support MPP (No in S21), the controller 17 maintains the induction mode (S4) and performs wireless charging in the induction mode (S5).

[0104] If the object to be charged 100 is compatible with MPP (Yes in S21), the controller 17 calculates the coupling coefficient k by Equation 3 using the voltage Vrect included in the configuration information (S2).

[0105] In addition, the Qi2 standard prescribes the calculation of the coupling coefficient k if the wireless charging function is MPP. The controller 17 calculates the coupling coefficient k while complying with the Qi2 standard.

[0106] The controller 17 determines whether the object to be charged 100 is located away from the object to be charged 100 by a distance threshold value THpd or not, depending on the coupling coefficient k calculated in S2 (S3).

[0107] If the coupling coefficient k exceeds the coefficient threshold THk, the controller 17 determines that the object to be charged 100 is not farther away than the distance threshold THpd (No in S3), maintains the induction mode (S4), and performs wireless charging in the induction mode (S5).

[0108] If the coupling coefficient k is lower than the coefficient threshold THk, the controller 17 determines that the object to be charged 100 is farther away than the distance threshold THpd (Yes in S3), and uses the information on the wireless charging function included in the configuration information to determine whether the object to be charged 100 supports EPP (S22).

[0109] If the object to be charged 100 does not support EPP (No in S22), the controller 17 maintains the induction mode (S4) and performs wireless charging in the induction mode (S5).

[0110] If the object to be charged 100 is compatible with EPP (Yes in S22), the controller 17 changes the operation mode from the induction mode to the resonance mode (S6), and switches the charging mode from MPP to EPP (S23).

[0111] In addition, the Qi2 standard does not allow the selection of EPP when both the charging device 1 and the object to be charged 100 support MPP, or the switching from MPP to EPP during charging. If the Qi2 standard were changed to allow the selection of EPP when both the charging device 1 and the object to be charged 100 support MPP, or the switching from MPP to EPP during charging, it would be possible to execute S23 while complying with the Qi2 standard.

[0112] Thereafter, steps S7 to S10 are carried out in the same manner as in the embodiment.

[0113] In this way, in the second modified example of the embodiment, the charging device 1 starts with MPP as a wireless charging function, and switches to EPP depending on the Z direction distance d from the object to be charged 100. This allows the charging device 1 to perform an operation that takes into account the standard.

[0114] (Third Modification) Furthermore, as a third modified example of the embodiment, when the controller 17 operates while taking into consideration the standards to the extent possible, the controller 17 may calculate the resonant frequency fr using the measured inductance value of the receiving coil 103 and the measured capacitance value of the capacitor 104 instead of the designed inductance value of the receiving coil 103 and the designed capacitance value of the capacitor 104.

[0115] For example, when the object to be charged 100 is manufactured, the inductance of the receiving coil 103 and the capacitance of the capacitor 104 may be measured and stored as the measured inductance value of the receiving coil 103 and the measured capacitance value of the capacitor 104, respectively, included in the configuration information.

[0116] In this case, in the configuration phase (SC20) shown in FIG. 4, when the controller 17 receives configuration information from the object to be charged 100, the controller 17 reads the inductance measurement value L of the receiving coil 103 included in the configuration information. 103 ' and the capacitance measurement C of the capacitor 104 104 The resonance frequency fr may be calculated by Equation 5 using the above formula.

[0117] The charging device 1 may perform the operation shown in Fig. 9 instead of that shown in Fig. 8. Fig. 9 is a flowchart showing the operation of the charging device 1 according to the third modified example of the embodiment.

[0118] After steps S1 to S23 are performed in the same manner as in the second modified example of the embodiment, the controller 17 receives the inductance measurement value L of the power receiving coil 103 included in the configuration information received in S21. 103 ' and the capacitance measurement C of the capacitor 104 104 The resonance frequency fr is calculated by using Equation 5 using ' (S11). After that, steps S8 to SI0 are performed in the same manner as in the second modified example of the embodiment.

[0119] This makes it possible to more accurately determine the resonance frequency fr, and to perform wireless charging with even higher efficiency when switching to the magnetic field resonance method.

[0120] (Fourth Modification) As a fourth modification of the embodiment, the charging device 1 may search for the resonance frequency fr by observing the communication response of the object to be charged 100 without calculating the coupling coefficient k, instead of calculating the coupling coefficient k and calculating the resonance frequency fr using the coupling coefficient k, as shown in Fig. 10. Fig. 10 is a flowchart showing the operation of the charging device 1 according to the fourth modification of the embodiment.

[0121] In the charging device 1, when the object to be charged 100 is placed on the placement surface 2a and the presence of the object to be charged 100 is detected, the controller 17 controls the drive frequency of the inverter circuit 13 to the resonant frequency fr when the object to be charged 100 is nearby (S31).

[0122] For example, the controller 17 may have setting information 174 as shown in Fig. 11. Fig. 11 is a diagram showing the data structure of the setting information 174 in the fourth modified example of the embodiment.

[0123] The setting information 174 corresponds to a plurality of different coupling coefficients and resonant frequencies. The setting information 174 has a coupling coefficient field 1741 and a resonant frequency field 1742. The coupling coefficient field 1741 records a value of the coupling coefficient. The resonant frequency field 1742 records a value of the resonant frequency. The resonant frequency value recorded in the resonant frequency field 1742 may be a value determined experimentally in advance. By referring to the setting information 174, it is possible to specify a value of the resonant frequency corresponding to the value of the coupling coefficient. By referring to the setting information 174, it is possible to specify that the resonant frequency fr=f1 corresponds to the coupling coefficient k=0.1. It is possible to specify that the resonant frequency fr=f2 corresponds to the coupling coefficient k=0.2. It is possible to specify that the resonant frequency fr=f7 corresponds to the coupling coefficient k=0.7. It is possible to specify that the resonant frequency fr=f8 corresponds to the coupling coefficient k=0.8. It is possible to specify that the resonant frequency fr=f9 corresponds to the coupling coefficient k=0.9. It can be determined that the resonant frequency fr=f10 corresponds to the coupling coefficient k=0.95.

[0124] The controller 17 may set the coupling coefficient k=0.9 when the object to be charged 100 is nearby, and refer to the setting information 174 to control the drive frequency of the inverter circuit 13 to the resonance frequency fr=f9 corresponding to the coupling coefficient k=0.9.

[0125] The controller 17 executes the digital ping (S32). The controller 17 controls the operating frequency of the inverter circuit 13 to the resonant frequency fr, and drives the power transmitting coil 3 at the resonant frequency fr. As a result, the controller 17 resonantly couples the power transmitting coil 3 and the power receiving coil 103, and transmits a digital ping from the power transmitting coil 3 to the power receiving coil 103 by the electric field resonance method.

[0126] As a response, the controller 17 receives the signal strength data SIG or the end power data EPT from the object to be charged 100. The controller 17 determines whether or not the response to the digital ping has been correctly received, depending on the contents of the signal strength data SIG or the end power data EPT (S34).

[0127] When the signal strength data SIG or the end power data EPT cannot be restored, or when it is determined that the restored data contains a bit error based on an error detection code or the like, the controller 17 determines that the response to the digital ping cannot be received correctly (No in S34). In response to this, the controller 17 changes the drive frequency of the inverter circuit 13 to the resonant frequency fr when the object to be charged 100 is one step farther away (S35).

[0128] For example, if the current resonant frequency is fr=f9 corresponding to the coupling coefficient k=0.9, the controller 17 refers to the setting information 174, reduces the coupling coefficient by one step to k=0.8, changes the drive frequency of the inverter circuit 13 to fr=f8 corresponding to the coupling coefficient k=0.8, and executes digital ping again (S32).

[0129] When the signal strength data SIG or the end power data EPT can be restored and it is determined that no bit error is included based on the error detection code or the like, the controller 17 determines that the response to the digital ping can be correctly received (Yes in S34). In response to this, the controller 17 completes the ping phase (SC10) shown in Fig. 4 for the object to be charged 100, and sequentially performs the configuration phase (SC20), the negotiation phase (SC30), and the power transmission phase (SC40) (S36). At this time, the operating frequency of the inverter circuit 13 is maintained at the value of the resonant frequency fr after the change.

[0130] In the power transmission phase (SC40), the controller 17 resonantly couples the power transmitting coil 3 and the power receiving coil 103 to perform wireless charging by a magnetic field resonance method. That is, the controller 17 controls the operating frequency of the inverter circuit 13 to the resonant frequency fr, and drives the power transmitting coil 3 at the resonant frequency fr. As a result, the controller 17 resonantly couples the power transmitting coil 3 and the power receiving coil 103, and transmits power from the power transmitting coil 3 to the power receiving coil 103 by an electric field resonance method.

[0131] Thus, in the fourth modified example of the embodiment, in the charging device 1, the controller 17 searches for the resonance frequency fr corresponding to the receiving coil 103 and the capacitor 104 while communicating with the object to be charged 100, and adjusts the drive frequency of the inverter circuit 13 to the searched resonance frequency fr to resonantly couple the transmitting coil 3 and the receiving coil 103. As a result, the transmitting coil 3 and the receiving coil 103 are resonantly coupled without calculating the coupling coefficient k, and power can be transmitted from the transmitting coil 3 to the receiving coil 103 by an electric field resonance method.

[0132] (Fifth Modification) For example, a power transmitting coil may be moved to the position of a power receiving coil of a terminal device with a built-in battery, and the terminal device may be wirelessly charged by the power transmitting coil. In such wireless charging, there is a demand for improved power efficiency. In order to improve power efficiency, the power transmitting coil and the power receiving coil are brought closer to each other, for example, by aligning the centers between the power transmitting coil and the power receiving coil. The position of the power receiving coil is roughly detected by multiple rows of position detection coils, and the position where the oscillation frequency of the AC power source is the highest is precisely detected as the position of the power receiving coil, while the power transmitting coil is brought closer to the power receiving coil.

[0133] However, in consideration of the recent market demand for high power efficiency, there is a demand for further improvement in power efficiency. In addition, for example, when a cover or case is attached to a terminal device, or when a mechanism for changing the relative positions of the power transmitting coil and the power receiving coil is provided, the power transmitting coil and the power receiving coil cannot be brought close enough due to physical restrictions, and sufficient power cannot be transmitted, resulting in reduced power efficiency.

[0134] Therefore, as a fifth modified example of the embodiment, another technique for improving power efficiency in wireless charging will be described. In the following, the case where the object to be charged by the charging device is a terminal device such as a smartphone, a tablet terminal, an audio player, or a mobile phone will be exemplified, but the object to be charged is not limited to a terminal device and may be any electronic device having a communication function and a wireless charging function.

[0135] 12 is a diagram showing an example of a schematic configuration of a charging system 201 according to an embodiment. The charging system 201 includes a charging device 210 and a terminal device 220, as shown in FIG.

[0136] The charging device 210 is a device that performs non-contact charging, that is, wireless charging, on a terminal device 220 to be charged that is placed on a placement surface 212A of the charging device 210.

[0137] Here, wireless charging means charging wirelessly. In the following, a form in which wireless charging means charging by electromagnetic induction will be described as an example.

[0138] In wireless charging, as an example, with the terminal device 220 to be charged placed on the upper surface (e.g., the placement surface 212A) of the placement section of the charging device 210, the power transmission coil 230 of the charging device 210 is moved by the moving mechanism 236 to approach the power receiving coil 222 of the terminal device 220, thereby aligning the power transmission coil 230 and the power receiving coil 222.

[0139] In wireless charging, the closer the power transmitting coil 230 of the charging device 210 and the power receiving coil 222 of the terminal device 220 to be charged are to a positional relationship in which they face each other, the more efficient the charging becomes. In consideration of the MPP (Magnetic Power Profile), the charging device 210 according to the present disclosure may have a magnet arranged together with the power transmitting coil 230.

[0140] The terminal device 220 as the target of charging by the charging device 210 is an example of an electronic device incorporating a battery 224. The terminal device 220 is configured to be operable using power from the built-in battery 224. The battery 224 is configured to be rechargeable by power wirelessly transmitted from the charging device 210.

[0141] The terminal device 220 further includes at least a power receiving coil 222. The power receiving coil 222 is configured to be able to receive power wirelessly transmitted from the charging device 210. The power receiving coil 222 is, for example, an induction coil that is electromagnetically coupled to the power transmitting coil 230 of the charging device 210. The power induced by the power receiving coil 222 is supplied to the battery 224.

[0142] A magnetic sheet 226 is provided on the back surface of the power receiving coil 222. The magnetic sheet 226 prevents malfunctions of various electronic circuits provided in the terminal device 220.

[0143] A mounting surface 212A is provided on the housing 212 of the charging device 210. The mounting surface 212A is a surface for mounting a terminal device 220 to be wirelessly charged. In the present embodiment, a form in which the mounting surface 212A is a partial area of ​​the outer surface of the housing 212 and is a two-dimensional planar area will be described as an example.

[0144] In the fifth modified example, the description will be made assuming that the placement surface 212A is a two-dimensional plane along a plane defined by a first direction and a second direction perpendicular to the first direction. Also, as shown in FIG. 12, the description will be made assuming that the first direction is the X-axis direction and the second direction is the Y-axis direction. The X-axis direction and the Y-axis direction are directions perpendicular to each other along the two-dimensional plane of the placement surface 212A. The description will be made assuming that the Z-axis direction perpendicular to the X-axis direction and the Y-axis direction coincides with the thickness direction of the housing 212. The Z-axis direction coincides with the opposing direction of the terminal device 220 and the charging device 210 placed on the placement surface 212A.

[0145] The charging device 210 has at least a power transmitting coil 230, a moving mechanism 236, a plurality of sensing coils 240, and a controller 250. For example, the power transmitting coil 230, the moving mechanism 236, the plurality of sensing coils 240, and the controller 250 are provided inside a housing 212 of the charging device 210.

[0146] The power transmitting coil 230 is a coil for transmitting power to the terminal device 220. In detail, the power transmitting coil 230 is a charging coil for generating an AC magnetic field for charging and supplying power to the power receiving coil 222 of the terminal device 220 by electromagnetic induction with the power receiving coil 222.

[0147] A magnetic sheet 232 is provided on the back surface of the power transmitting coil 230. The magnetic sheet 232 prevents the AC magnetic field generated by the power transmitting coil 230 from affecting various electronic circuits provided in the region of the power transmitting coil 230 on the opposite side of the detection coil 240 in the charging device 210. The magnetic sheet 232 also effectively supplies power from the AC magnetic field generated by the power transmitting coil 230 to the power receiving coil 222. That is, the magnetic sheet 232 contributes to preventing malfunction of various electronic circuits provided in the charging device 210 and improving the efficiency of power transmission from the power transmitting coil 230 to the power receiving coil 222.

[0148] In the fifth modification, the power transmitting coil 230 is placed on a transport stand 234 with a magnetic sheet 232 therebetween.

[0149] The moving mechanism 236 is a mechanism that changes the relative position between the power transmitting coil 230 and the power receiving coil 222. In the fifth modified example, the moving mechanism 236 is a mechanism that moves the power transmitting coil 230 along the mounting surface 212A. In the fifth modified example, the moving mechanism 236 moves the transport table 234, on which the magnetic sheet 232 and the power transmitting coil 230 are mounted in this order, along the mounting surface 212A, thereby moving the power transmitting coil 230 mounted on the transport table 234 together with the magnetic sheet 232 along the mounting surface 212A.

[0150] The moving mechanism 236 is configured using at least one driving motor such as a stepping motor or a servo motor, a support member, etc. The moving mechanism 236 is configured to be able to move the transport platform 234 in each of the X-axis direction and the Y-axis direction along the mounting surface 212A by driving the driving motor. In other words, the power transmitting coil 230 is configured to be able to move by the moving mechanism 236 along a two-dimensional plane that is the XY plane along the mounting surface 212A.

[0151] The multiple detector coils 240 are a coil group for detecting the position of the power receiving coil 222 of the terminal device 220 on the placement surface 212A. The position of the power receiving coil 222 of the terminal device 220 is represented by a position on a two-dimensional plane consisting of an XY plane along the placement surface 212A. When the power receiving coil 222 is a circular induction coil as shown in FIG. 12, the position of the power receiving coil 222 is defined as, for example, the position of the center point of the circle on the XY plane along the placement surface 212A. The multiple detector coils 240 are arranged along the placement surface 212A below the placement surface 212A within the housing 212 of the charging device 210. For example, the multiple detector coils 240 are arranged in a matrix in a direction intersecting each other. Here, the multiple detector coils 240 are an example of a detection unit.

[0152] Note that the charging device 210 only needs to be configured to be able to detect the position of the power receiving coil of the terminal device 220 placed on the placement surface 212A, and may have other configurations as a detection unit than the multiple detection coils 240. In this case, for example, the charging device 210 may be provided with various sensors such as a weight sensor, a pressure sensor, or an optical sensor capable of detecting the position of the terminal device 220 placed on the placement surface 212A, or a camera that captures the placement surface 212A, as a detection unit.

[0153] Fig. 13 is a diagram showing an example of a configuration related to power transmission of the charging system 201 of Fig. 12. The charging device 210 further includes an AC power supply 261, a resonance capacitor 263, and a switch 265 for feeding power to a coil.

[0154] In the example of FIG. 13, one end of the power transmission coil 230 of the charging device 210 is electrically connected to one end of an AC power supply 261 via a resonance capacitor 263, and the other end is electrically connected to the other end of the AC power supply 261 via a coil power supply switch 265.

[0155] In the example of FIG. 13, one end of each of the multiple detection coils 240 of the charging device 210 is electrically connected to one end of the AC power supply 261 on the side of the resonance capacitor 263, and the other end is electrically connected to the other end of the AC power supply 261 via the coil power supply switch 265.

[0156] 13, one end of the power receiving coil 222 of the terminal device 220 is electrically connected to the load 223 via the capacitance 221, and the other end is electrically connected to the other end of the load 223. Note that the capacitance 221 can be configured by, for example, the stray capacitance of the power receiving coil 222, but a capacitor may also be actually provided. The load 223 includes a battery 224.

[0157] One end of the AC power supply 261 is electrically connected to the resonance capacitor 263, and the other end is electrically connected to the coil power supply switch 265. The AC power supply 261 outputs AC power to be supplied to the power transmitting coil 230 or the multiple detection coils 240, using power from an external power supply provided outside the charging device 210, such as an in-vehicle battery or a commercial power supply, or a battery mounted in the charging device 210.

[0158] The resonance capacitor 263 is electrically connected between the AC power supply 261 and the power transmitting coil 230. The resonance capacitor 263 is configured to have a variable capacitance. The resonance capacitor 263 is configured to be able to adjust the resonance frequency (induction frequency) on the power transmitting coil 230 side by changing the capacitance. For example, the resonance capacitor 263 may be a plurality of capacitors that are selectively enabled, or a capacitor with a variable capacitance.

[0159] FIG. 13 illustrates a resonance capacitor 263 in which a plurality of capacitors 2631 are selectively enabled by a plurality of switches 2633, thereby making the capacitance thereof variable. In the example of FIG. 13, the plurality of capacitors 2631 include a first capacitor 2631a, a second capacitor 2631b, and a third capacitor 2631c. Each of the plurality of switches 2633 is configured to switch on and off according to the control of the controller 250. The plurality of switches 2633 include a first switch 2633a and a second switch 2633b. The first capacitor 2631a has one end electrically connected to the AC power supply 261, and the other end electrically connected to the power transmitting coil 230. The second capacitor 2631b has one end electrically connected to the AC power supply 261, and the other end electrically connected to the power transmitting coil 230 via the first switch 2633a. The third capacitor 2631c has one end electrically connected to the AC power supply 261, and the other end electrically connected to the power transmitting coil 230 via the second switch 2633b. Therefore, the resonance capacitor 263 in Fig. 13 can change its capacitance in four stages depending on the on / off states of the first switch 2633a and the second switch 2633b.

[0160] The number of the plurality of capacitors 2631 and the capacitance of each of them may be appropriately determined depending on, for example, the adjustment range of the resonant frequency and the number of adjustment stages. Similarly, the number of the plurality of switches 2633 may be appropriately determined depending on, for example, the adjustment range of the resonant frequency and the number of adjustment stages, and the number of the plurality of capacitors 2631 and the capacitance of each of them.

[0161] The coil power supply switch 265, under the control of the controller 250, switches the coil to which one end of the AC power supply 261 on the opposite side to the resonance capacitor 263 is electrically connected, between the power transmission coil 230 and the multiple detection coils 240. Note that the coil power supply switch 265, under the control of the controller 250, can also set the one end of the AC power supply 261 on the opposite side to the resonance capacitor 263 to a state in which it is not electrically connected to either the power transmission coil 230 or the multiple detection coils 240.

[0162] The coil power supply switch 265 may include a switch for switching on / off the supply of AC power to the power transmission coil 230, and a switch for switching on / off the supply of AC power to the plurality of detection coils 240. The coil power supply switch 265 may be provided as a part of the AC power supply 261.

[0163] For example, when the coil power supply switch 265 electrically connects one end of the AC power supply 261 opposite the resonance capacitor 263 to the transmitting coil 230 under the control of the controller 250, the transmitting coil 230 is electromagnetically coupled to the receiving coil 222 of the terminal device 220 to supply AC power from the AC power supply 261 to the receiving coil 222.

[0164] Here, the efficiency of power transmission from the power transmitting coil 230 to the power receiving coil 222, i.e., the power efficiency, correlates with the coupling coefficient of this electromagnetic coupling. The coupling coefficient is defined as a value between 0 and 1. For example, when the coupling coefficient is "0", the magnetic flux Mf1 from the power transmitting coil 230 is not transmitted to the power receiving coil 222, indicating a state of no coupling. On the other hand, when the coupling coefficient is "1", the magnetic flux Mf1 from the power transmitting coil 230 indicates a state of complete coupling with no leakage magnetic flux Mf2. However, a maximum coupling coefficient does not necessarily mean that the power efficiency between the coils is maximum.

[0165] The AC power supplied to the power receiving coil 222 is converted to DC power by a rectifier (not shown) of the load 23 provided in the terminal device 220, and charges the battery 224 of the load 223 built in the terminal device 220. As a result, the battery 224 of the terminal device 220 is wirelessly charged.

[0166] The controller 250 is configured to control the operation of the charging device 210 and to execute, for example, a charging process. Fig. 14 is a diagram showing an example of the configuration of the controller 250 in Fig. 12.

[0167] The controller 250 includes a processor 251, a storage unit 253, and a communication interface 255. Here, the controller 250 according to the embodiment is an example of a control unit.

[0168] The processor 251 controls the overall operation of the controller 250. The processor 251 reads out a control program 2531 stored in, for example, a ROM (Read Only Memory) of the storage unit 253, and executes the control program 2531 loaded into a RAM (Random Access Memory) of the storage unit 253, thereby realizing functions as a detection function 2511, a communication function 2512, a drive function 2513, and a fine adjustment function 2514.

[0169] As the processor 251, various types of processors such as a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), or a field programmable gate array (FPGA) can be appropriately used.

[0170] In the detection function 2511, the processor 251 controls the multiple detection coils 240 to detect the position of the power receiving coil 222. For example, the processor 251 selectively outputs a signal for generating a magnetic field for detection to each of the multiple detection coils 240 in sequence. The processor 251 is also configured to identify the arrangement position of the terminal device 220 to be charged, i.e., the position of the power receiving coil 222, based on an echo signal detected by each of the multiple detection coils 240 in response to the magnetic field for detection from the power receiving coil 222.

[0171] In the communication function 2512, the processor 251 controls the power transmitting coil 230 and communicates with the power receiving coil 222. For example, the processor 251 is configured to communicate with the terminal device 220 via the power transmitting coil 230 when the power transmitting coil 230 is moved to a position facing the power receiving coil 222 of the terminal device 220 by the control of the drive function 2513.

[0172] Here, the communication function between the charging device 210 and the terminal device 220 will be described. As described above, the power transmitting coil 230 of the charging device 210 and the power receiving coil 222 of the terminal device 220 can be electromagnetically coupled, and the charging device 210 and the terminal device 220 communicate with each other using this electromagnetic coupling. For example, by adjusting the loads of the power transmitting coil 230 and the power receiving coil 222, the charging device 210 and the terminal device 220 transmit data as fluctuations in the coupling field. Specifically, the charging device 210 transmits data modulated by FSK (Frequency Shift Keying) to the terminal device 220. Furthermore, when the charging device 210 receives data modulated by load modulation in the terminal device 220, it demodulates the data. These processes enable information exchange between the charging device 210 and the terminal device 220.

[0173] In the driving function 2513, the processor 251 controls the moving mechanism 236 to change the relative position between the coils based on the detected position of the power receiving coil 222. The adjustment of the relative position between the coils is a first stage adjustment in the control process, and can be expressed as a "rough adjustment" or a "coarse adjustment". Here, the "rough adjustment" is an example of a first adjustment. The relative position after the "rough adjustment" is an example of a first relative position. For example, the processor 251 is configured to move and position the power transmitting coil 230 to a charging start position corresponding to the detected position of the terminal device 220 to be charged, and transmit power to the power transmitting coil 230. Here, the charging start position is the position where the terminal device 220 is placed, that is, the position facing the detected position of the power receiving coil 222, and is the relative position after the "rough adjustment". In other words, the processor 251 starts charging control to transmit power to the terminal device 220 at the relative position after the "rough adjustment". Typically, the horizontal positions of the charging start position and the detection position of the power receiving coil 222, i.e., the positions as viewed from above, match or nearly match. In other words, at the charging start position, the center positions of the power transmitting coil 230 and the power receiving coil 222 match or nearly match.

[0174] In the fine adjustment function 2514, the processor 251 is configured to execute at least one of a fine adjustment process based on the control of the resonance capacitor 263 (see FIG. 16 ) and a fine adjustment process based on a change in the coil relative position (see FIG. 17 ) when the power transmission coil 230 is moved to the charging start position and power transmission by the power transmission coil 230 is started.

[0175] For example, in a fine adjustment process based on the control of the resonance capacitor 263, the processor 251 adjusts the resonance frequency of the power wirelessly transmitted from the power transmitting coil 230 by controlling the capacitance of the resonance capacitor 263 based on a parameter (communication information) related to a coupling coefficient, prior to "fine adjustment" of the relative position between the coils described later. Note that this adjustment of the resonance frequency is a second-stage adjustment in the control process according to this embodiment, and is an example of a third adjustment.

[0176] For example, in a fine adjustment process based on a change in the coil relative position, the processor 251 controls the moving mechanism 236 to change the relative position between the coils from the relative position after adjustment by the "coarse adjustment" based on information (communication information) related to the amount of power received from the power receiving coil 222 by communication. This adjustment of the relative position between the coils is a second stage adjustment in the control process according to this embodiment, and can be expressed as "fine adjustment" or "precise adjustment". Here, the "fine adjustment" of the relative position between the coils is an example of a second adjustment. Also, the relative position after the "fine adjustment" of the relative position between the coils is an example of a second relative position. As an example, the second relative position is a position different from the first relative position, and is a position where the center positions of the power transmitting coil 230 and the power receiving coil 222 do not match. Typically, the second relative position is a peak position of power efficiency, which is the ratio of the amount of power received by the power receiving coil 222 to the power wirelessly transmitted from the power transmitting coil 230.

[0177] The storage unit 253 can use various storage media and storage devices such as a ROM, a hard disk drive (HDD), a solid state drive (SSD), a flash memory, etc. as appropriate as a hardware configuration. The storage unit 253 is further provided with a RAM for temporarily storing data being worked on. The storage unit 253 stores various data and programs used by the controller 250.

[0178] The communication interface 255 is configured to be able to wirelessly communicate with a terminal device to be charged. The communication interface 255 has a communication circuit for wireless communication as a hardware configuration. As the communication circuit for wireless communication, a communication circuit compatible with various standards such as 4G, 5G, 6G, Wi-Fi (registered trademark), Bluetooth (registered trademark), and infrared communication can be appropriately used.

[0179] Next, a description will be given of the flow of control processing executed by the charging device 210 configured as above. Fig. 15 is a flowchart showing an example of the flow of control processing executed by the charging device of Fig. 12.

[0180] The detection function 2511 detects the terminal device 220 placed on the placement surface 212A by the multiple detection coils 240 (S41). As an example, the detection function 2511 controls the coil power supply switch 265 to electrically connect one end of the AC power supply 261 opposite to the resonance capacitor 263 to the multiple detection coils 240, and starts detection of the terminal device 220. Note that the detection of the terminal device 220 is performed at any time at a predetermined period that is, for example, predetermined and stored in the storage unit 253 or the like.

[0181] The detection function 2511 determines whether the terminal device 220 has been detected (S42). If the terminal device 220 has not been detected (S42: No), the process returns to S41.

[0182] On the other hand, if the terminal device 220 is detected (S42: Yes), the detection function 2511 identifies the detected position of the terminal device 220, that is, the position of the power receiving coil 222 (S43).

[0183] Furthermore, the driving function 2513 controls the moving mechanism 236 to move the power transmitting coil 230 to the identified position of the power receiving coil 222 (S44). As an example, the driving function 2513 performs a "coarse adjustment" to adjust the relative positions of the power transmitting coil 230 and the power receiving coil 222 so that their central positions match or approximately match. Here, "approximately matching central positions between the coils" means that the central positions are close to the matching position.

[0184] The driving function 2513 switches the power supply to the power transmitting coil 230 that has been "coarsely adjusted" (S45). As an example, the driving function 2513 controls the coil power supply switch 265 at the stage when the "coarse adjustment" is completed, thereby electrically connecting one end of the AC power source 261 on the opposite side to the resonance capacitor 263 to the power transmitting coil 230, and switches the supply destination of the AC power to the power transmitting coil 230.

[0185] Thereafter, the communication function 2512 establishes communication with the terminal device 220 (S46). After the communication with the terminal device 220 is established, the fine-tuning function 2514 performs a fine-tuning process based on the control of the resonance capacitor 263 (S47). The fine-tuning process based on the control of the resonance capacitor 263 will be described later (see FIG. 16). The drive function 2513 drives the power transmitting coil 230 and starts a charging operation including power transmission from the power transmitting coil 230 to the power receiving coil 222 (S48). After performing the fine-tuning process based on the control of the resonance capacitor 263, the fine-tuning function 2514 performs a fine-tuning process based on a change in the coil relative position (S49). The fine-tuning process based on a change in the coil relative position will be described later (see FIG. 17).

[0186] Here, the fine adjustment process based on the control of the resonance capacitor 263 will be described with reference to the drawings. Fig. 16 is a flow chart showing an example of the flow of the fine adjustment process based on the control of the resonance capacitor 263 in the control process of Fig. 15 .

[0187] The fine-tuning function 2514 acquires a parameter related to the coupling coefficient by using the communication established with the terminal device 220 (S101). The parameter related to the coupling coefficient is information related to the coupling coefficient of the electromagnetic coupling between the power receiving coil 222 and the power transmitting coil 230, and is an example of communication information. The parameter related to the coupling coefficient may be the value of the coupling coefficient itself, or may be various values ​​required for calculating the coupling coefficient. That is, the calculation of the coupling coefficient may be performed by the terminal device 220 or may be performed by the charging device 210.

[0188] For example, the fine tuning function 2514 calculates a coupling coefficient based on the distance between the coils, the angle, the relative size and shape of each coil.

[0189] Up to this point, the transmission of power used for charging has been described as using a natural phenomenon called electromagnetic induction, but when the resonant frequencies of charging device 210 and terminal device 220 match, the phenomenon of electromagnetic induction transitions to a phenomenon called magnetic field resonance in which they resonate with each other, and a phenomenon occurs in which power can be transmitted even if charging device 210 and terminal device 220 are far apart. This phenomenon is generally called magnetic field resonance, magnetic resonance, resonant mode, or resonant mode.

[0190] In principle, the coupling coefficient is proportional to the magnitude of mutual inductance between the coils and is not affected by the value of the capacitor. However, depending on the calculation method, in the case of phenomena known as magnetic field resonance, magnetic resonance, resonant mode, and resonance mode (hereinafter referred to as resonant mode), it can be affected by the value of the capacitor and the value of the resonant frequency.

[0191] Since the coupling coefficient cannot actually be measured directly, one method is to measure the electromotive force of the terminal device 220 and calculate an approximation based on inherent parameters such as the distance between the coils, the angle, the relative size, and the shape of each coil, as mentioned above.

[0192] Furthermore, in the case of the resonant mode, the electromotive force of the terminal device 220 varies with the resonant frequency, and as a result, the coupling coefficient depends on the resonant frequency and on the capacitance value of the resonant circuit.

[0193] Thus, in the case of the resonant mode, when the resonant frequencies of the charging device 210 and the terminal device 220 approximately match, the coupling coefficient is maximized.

[0194] It should be noted that the shape and size of the power transmitting coil 230 are, for example, set in advance and stored in the storage unit 253. In the "coarse adjustment" according to the present disclosure, the relative positions are adjusted so that the center positions of the coils match or approximately match, for example, and therefore the distance and angle between the coils may be treated as known values.

[0195] Furthermore, for example, a predetermined value may be prepared in advance for the distance between the coils in the thickness direction (Z-axis direction) of charging device 210. This specified value may be prepared for each relative size between the coils, the shape of each coil, and the charging standard, or may be calculated by correcting the predetermined value based on the relative size between the coils, the shape of each coil, and the charging standard.

[0196] Furthermore, the fine adjustment function 2514 may approximately calculate the value of the coupling coefficient using the above formulas 2 and 3 based on the electromotive force of the terminal device 220, for example.

[0197] In other words, the ratio p of the electromotive force Vrect of the terminal device 220 to the power (VCTX_PP+Vin) of the charging device 210 in Equation 3 is approximated as a linear expression via inherent parameters in Equation 2 to calculate the coupling coefficient k.

[0198] In Equation 2, E0 is a parameter specific to the circuit characteristics that affects the output voltage of charging device 210. E1 is a parameter specific to the circuit characteristics that corresponds to the input voltage of charging device 210. E0 and E1 are each calculated in advance by calibration or the like, and are used as the basis for calculating coupling coefficient k by approximating it with a linear expression.

[0199] That is, Vrect is received by communication from terminal device 220 to charging device 210, and coupling coefficient k is calculated by approximating the linear expression using characteristic parameter E0 corresponding to the slope of the linear expression and characteristic parameter E1 corresponding to the intercept of the linear expression.

[0200] Here, the coupling coefficient k calculated by this approximation is merely an approximate calculation that assumes electromagnetic induction.

[0201] On the other hand, in the case of the resonant mode, when the resonant frequencies of the charging device 210 and the terminal device 220 roughly match, the electromotive force Vrect of the terminal device 220 behaves as if it has a maximum value, and therefore the coupling coefficient calculated by Equation 2 and Equation 3 also behaves as if it has a maximum value depending on the resonant frequency.

[0202] That is, by switching the capacitor of the resonance capacitor 263, the resonance frequency of the charging device 210 can be changed, and the coupling coefficient can be set to a maximum value (maximum value). The method is described below.

[0203] The fine-tuning function 2514 switches the capacitance of the resonance capacitor 263 so as to maximize the coupling coefficient (S102). For example, the fine-tuning function 2514 controls the on / off of each of the multiple switches 2633 to switch which of the multiple capacitors 2631 is to be enabled.

[0204] It should be noted that the correspondence between the value or range of the coupling coefficient and the capacitor to be enabled is, for example, set in advance and stored in the storage unit 253. In other words, the fine-tuning function 2514 specifies the capacitor to be enabled by referring to the storage unit 253 according to the coupling coefficient.

[0205] The correspondence between the coupling coefficient and the capacitor may indicate a capacitor to be enabled for each value or range of the coupling coefficient, or may indicate the on / off state of each of the multiple switches 2633 for each value or range of the coupling coefficient. Alternatively, the resonance capacitor 263 may be provided with a dedicated circuit (not shown) that switches on / off each of the multiple switches 2633 in response to an input of a coupling coefficient value. In this case, the fine adjustment function 2514 may output a signal indicating a value of the coupling coefficient in order to switch the capacitor of the resonance capacitor 2633 so that the coupling coefficient is maximized, instead of a control signal for controlling each of the multiple switches 2633.

[0206] Here, the fine adjustment process based on the change in the relative position of the coils will be described with reference to the drawings. Fig. 17 is a flow chart showing an example of the flow of the fine adjustment process based on the change in the relative position of the coils in the control process of Fig. 15 .

[0207] The fine adjustment function 2514 sets the X direction as the movement direction of the power transmitting coil 230 (S201).

[0208] The fine-tuning function 2514 moves the power transmitting coil 230 by "+1" step (S202). The fine-tuning function 2514 also acquires information on the amount of received power from the terminal device 220 (S203). The information on the amount of received power is, for example, information on the amount of power received by the power receiving coil 222 of the terminal device 220 with respect to the power wirelessly transmitted from the power transmitting coil 230, and is an example of communication information. The information on the amount of received power includes, for example, the value of the amount of power. Note that the information on the amount of received power may further include a parameter related to a coupling coefficient. In this case, the coupling coefficient may be acquired by correcting the previously calculated coupling coefficient based on, for example, a change in the distance or angle between the coils due to a change in the relative position of the coils. The fine-tuning function 2514 also determines whether the received power has decreased (S204). In addition, when the transmission power to be transmitted changes, the fine adjustment function 2514 may determine in this step whether the power efficiency (power transmission efficiency) obtained by dividing the value of the received power by the value of the transmitted power has decreased. If the received power has not decreased (S204: No), the process returns to S202.

[0209] If the received power has decreased (S204: Yes), the fine-tuning function 2514 moves the power transmitting coil 230 by "-1" step (S205). The fine-tuning function 2514 also acquires information on the amount of received power from the terminal device 220 in the same manner as S203 (S206). The fine-tuning function 2514 also determines whether the received power has decreased (S207) in the same manner as S204. If the received power has not decreased (S207: No), the process returns to S205. In this way, the fine-tuning function 2514 repeats the same processes as S202 to S204 with the movement direction of the power transmitting coil 230 reversed.

[0210] If the received power has decreased even after the moving direction is reversed (S207: Yes), the fine-tuning function 2514 moves the transmitting coil 230 back one step (S208). That is, the fine-tuning function 2514 moves the transmitting coil 230 by "+1" step. In this manner, the fine-tuning function 2514 moves the transmitting coil 230 in that moving direction to a position where the received power peaks as the resonant frequency changes with the change in the coil relative position, that is, to a position where the power efficiency is at its peak.

[0211] Thereafter, the fine adjustment function 2514 determines whether the processing for all directions is complete (S209). If the processing for all directions is not complete (S209: No), the fine adjustment function 2514 sets the Y direction as the movement direction for the movement of the power transmitting coil 230 (S210). Thereafter, the process returns to S202, and S202 to S208 for the Y direction are performed in the same manner as S202 to S208 for the X direction. Then, if the processing for all directions is complete (S209: Yes), the process ends.

[0212] 17 illustrates an example in which the power transmitting coil 230 is moved to the position of the power efficiency peak in the X direction, and then moved to the position of the power efficiency peak in the Y direction, but is not limited thereto. The flow in FIG. 17 may be a flow in which processing is performed in the Y direction first. Also, the order of movement in each movement direction, specifically, the processing order of S202 to S204 and S205 to S207, may be interchanged.

[0213] In this manner, the charging device 210 according to the embodiment is configured to perform "fine tuning" by changing the relative coil position to adjust the resonance frequency, and move the power transmitting coil 230 to the efficiency peak of the power efficiency. This configuration makes it possible to realize a state in which the coil centers are shifted between the power transmitting coil 230 and the power receiving coil 222, that is, charging at the efficiency peak. Therefore, according to the charging device 210 according to the embodiment, the power efficiency in wireless charging can be improved by charging using resonance.

[0214] More specifically, the charging device 210 according to the embodiment is configured to start charging at the stage where "rough adjustment" is completed, that is, before "fine adjustment". In other words, the charging device 210 according to the embodiment is configured to perform two-stage control: a first stage in which, for example, the coil centers are aligned to maximize the coupling coefficient and match the resonance frequency based on the detection results of the multiple detection coils 240, and a second stage in which fine adjustment is performed to align the relative position of the coils with the efficiency peak of the power efficiency at which the received power is maximized. With this configuration, charging can be started in a state where the position is determined by "rough adjustment". More specifically, with the above configuration, power efficiency can be improved by "fine adjustment" after "rough adjustment", so there is no need to configure the charging to not start unless the charging power exceeds a certain level (for example, 5 W) specified by the charging standard, and charging can be started quickly.

[0215] Moreover, the charging device 210 according to the embodiment is configured to adjust the resonance frequency by changing the coil relative position after adjusting the resonance frequency by controlling the capacitance of the resonance capacitor 263 in "fine adjustment" after completing the "coarse adjustment". According to this configuration, the resonance frequency can be roughly adjusted by electrical adjustment by controlling the capacitance of the resonance capacitor 263, and then the resonance frequency can be adjusted by changing the coil relative position. In other words, in the "fine adjustment", the power transmitting coil 230 is moved to a position where the power efficiency is at its peak based on the coupling coefficient and the power transmitted from the power transmitting coil 230 to the power receiving coil 222. Therefore, according to the above configuration, it is possible to speed up the fine adjustment for moving the power transmitting coil 230 to the power efficiency peak and to expand the adjustment range.

[0216] Furthermore, with the above configuration, it is possible to make "fine adjustments" to match the peak of power efficiency at that time in response to efficiency degradation due to temperature changes and position shifts caused by vibrations in the relative position of the coils between the transmitting coil 230 and the receiving coil 222, and therefore it is possible to track such changes. Therefore, with the above configuration, it is possible to suppress deterioration in power efficiency due to temperature changes and position shifts caused by vibrations in the relative position of the coils.

[0217] Furthermore, according to the above configuration, even when a charging frequency (e.g., 360 kHz) is specified, for example, as in the MPP standard, that is, even when the driving frequency of charging by the AC power supply 261 cannot be adjusted, it is possible to improve power efficiency.

[0218] (Sixth Modification) In addition, in the charging device 210 according to the present disclosure, the second stage of “fine-tuning” for improving power efficiency may be performed, for example, by only one of the fine-tuning process based on control of the resonant capacitor and the fine-tuning process based on a change in the relative position of the coil.

[0219] Also, for example, fine adjustment function 2514 may adjust the resonance frequency by adjusting the drive frequency of charging by AC power supply 261 as "fine adjustment" depending on the charging standard.

[0220] Even with these configurations, the same effects as those of the fifth modified example of the above-described embodiment can be obtained.

[0221] (Seventh Modification) In addition, in charging device 210 according to the present disclosure, the change in the relative position (coil relative position) between power transmitting coil 230 and power receiving coil 222 may be achieved by other methods of moving power transmitting coil 230.

[0222] For example, the charging device 210 may be configured to detachably support the terminal device 220 to be charged on the placement surface 212A. In this case, the "coarse adjustment" may be performed by attaching the terminal device 220 to a support section provided so that the power receiving coil 222 is positioned in accordance with the position of the power transmitting coil 230. Alternatively, the charging device 210 may be configured to perform the "coarse adjustment" by moving the attached terminal device 220, for example, by configuring a support section that detachably supports the terminal device 220 to be movable.

[0223] The support unit supports the terminal device 220 on the placement surface 212A, thereby defining the relative position between the power transmitting coil 230 and the power receiving coil 222 at a predetermined relative position. Here, the predetermined relative position defined by the support unit is an example of a first relative position. The support unit may be configured, for example, as a recess into which the terminal device 220 can be fitted. Alternatively, the support unit may be configured, for example, to sandwich and hold the terminal device 220. In this case, the support unit may be provided with, for example, a movable part for sandwiching the terminal device 220. The movable part may be biased by an elastic member such as a spring, or may be configured to be fixable by a screw or the like. Alternatively, the support unit may be configured, for example, as a magnet provided together with the power transmitting coil 230. This magnet may be realized by a permanent magnet or an electromagnet as long as it can attract the magnet provided together with the power receiving coil 222 of the terminal device 220. Furthermore, the magnet provided together with the power transmitting coil 230 may be configured to be movable independently of the power transmitting coil 230. For this reason, the moving mechanism that moves the magnet may be configured integrally with the moving mechanism 236 that moves the power transmitting coil 230, or may be provided independently.

[0224] The moving mechanism for moving the support unit may share a part of the moving mechanism 236 according to the above embodiment, may be provided separately as an independent moving mechanism, or may be provided in place of the moving mechanism 236. That is, in the charging device 210 configured to be able to move the terminal device 220 by the support unit, the power transmitting coil 230 does not have to be configured to be movable. In these configurations, the "fine adjustment" based on the change in the relative position of the coils is performed, for example, by moving the support unit, but may be performed by moving the power transmitting coil 230, or may be performed by moving both. The support unit does not have to be moved in the "coarse adjustment".

[0225] Even with these configurations, the same effects as those of the fifth modified example of the above-described embodiment can be obtained.

[0226] (Eighth Modification) The charging device 210 may have a plurality of power transmission coils 230 in order to charge a plurality of terminal devices 220. In this case, since charging is possible even at a distance due to fine adjustment of the resonant frequency, there is a risk of crosstalk occurring in communication between the terminal device 220 newly placed on the placement surface 212A and the terminal device 220 already being charged.

[0227] For this reason, the fine adjustment function 2514 may be configured to perform only the first stage of "coarse adjustment" and not the second stage of "fine adjustment" when the distance between the terminal devices 220 is smaller than a threshold value previously set and stored in the storage unit 253, for example. Note that in the charging device 210 according to the present disclosure, the terminal position on the placement surface 212A can be accurately grasped based on the detected positions by the multiple detection coils 240, the calculated coupling coefficients, and the like.

[0228] Further, the fine adjustment function 2514 may determine the degree of resonance, such as whether to move closer to or farther from the resonance point, in addition to determining whether or not to execute "fine adjustment" based on a distance threshold. That is, the fine adjustment function 2514 may determine the presence or absence and the degree of resonance based on the positional relationship between the terminal devices 220, such as adjusting the driving frequency of charging by the AC power source 261, fine adjustment by switching a capacitor to be enabled among the multiple capacitors 2631 of the resonance capacitor 263, and fine adjustment by changing the relative position of the coil.

[0229] Also, the fine-tuning function 2514 may, for example, adjust the resonance frequency by "fine-tuning", that is, when charging using resonance and another terminal device 220 is newly placed at a distance closer than a threshold, avoid resonance in charging the terminal device 220 being charged, that is, slow down the charging speed. Also, for the newly placed terminal device 220, for example, after starting charging without using resonance, the fine-tuning function 2514 may adjust the resonance frequency by "fine-tuning" to improve power efficiency after the terminal device 220 that was previously being charged is moved or its charging is completed.

[0230] According to these configurations, even in a configuration in which multiple terminal devices 220 are charged, if the distance between the terminals is sufficient or if they are far apart, charging can be performed efficiently through resonance, and if the distance between the terminals is short, resonance can be avoided and the occurrence of crosstalk can be suppressed.

[0231] The charging device 210 according to the fifth to eighth modified examples described above can be used as, for example, an in-vehicle device, but is not limited thereto. It can also be used as various wireless chargers conforming to standards such as the Qi standard, such as devices used on a desk.

[0232] The programs executed by charging device 210 of the fifth to eighth variants are provided in the form of files in an installable or executable format recorded on a computer-readable recording medium such as a CD-ROM, FD, CD-R, or DVD.

[0233] The programs executed by the charging device 210 of the fifth to eighth modified examples may be stored on a computer connected to a network such as the Internet and provided by being downloaded via the network. The programs executed by the charging device 210 may be provided or distributed via a network such as the Internet.

[0234] Moreover, the programs executed by the charging device 210 of the fifth to eighth modifications may be configured to be provided by being pre-installed in a ROM or the like.

[0235] According to at least one of the fifth to eighth modified examples described above, it is possible to improve the power efficiency in wireless charging.

[0236] (Ninth Variation) As a ninth modification of the embodiment, the charging device 1 (see Fig. 3) may perform the operation shown in Fig. 18 instead of Fig. 6. Fig. 18 is a flowchart showing the operation of the charging device 1 according to the ninth modification of the embodiment.

[0237] After steps S1 to S9 are performed in the same manner as in the embodiment, the controller 17 performs fine adjustment processing based on the change in the relative coil position (S49i). The controller 17 performs processing equivalent to steps S201 to S210 in FIG. 17 as the fine adjustment processing based on the change in the relative coil position.

[0238] For example, the controller 17 sets the X direction as the movement direction of the power transmitting coil 3 (S201).

[0239] The controller 17 moves the power transmitting coil 3 by "+1" step (S202). In addition, the controller 17 acquires information on the amount of received power from the object to be charged 100 (S203).

[0240] The controller 17 determines whether the received power has decreased (S204). If the received power has not decreased (S204: No), the process returns to S202.

[0241] If the received power has decreased (S204: Yes), the controller 17 moves the power transmitting coil 3 by "-1" step (S205). The controller 17 acquires information on the amount of received power from the object to be charged 100 in the same manner as in S203 (S206). The controller 17 determines whether the received power has decreased (S207) in the same manner as in S204. If the received power has not decreased (S207: No), the process returns to S205. In this way, the controller 17 repeats the same processes as in S202 to S204 with the moving direction of the power transmitting coil 3 reversed.

[0242] If the received power decreases even after the moving direction is reversed (S207: Yes), the controller 17 moves the power transmitting coil 3 back by one step (S208).

[0243] The controller 17 determines whether the processing for all directions is complete (S209). If the processing for all directions is not complete (S209: No), the controller 17 sets the Y direction as the movement direction for the movement of the power transmitting coil 3 (S210). Thereafter, the process returns to S202, and S202 to S208 for the Y direction are performed in the same manner as S202 to S208 for the X direction. Then, if the processing for all directions is complete (S209: Yes), the process ends.

[0244] After S49i, SI0 is performed in the same manner as in the embodiment.

[0245] In this way, in the charging device 1, by performing fine adjustment processing based on the change in the relative position of the coil after S9, the drive frequency can be made closer to the resonance frequency on the side of the object to be charged 100, and the efficiency of power transmission can be further improved.

[0246] (Tenth Variation) As a tenth modification of the embodiment, the charging device 1 (see Fig. 3) may perform the operation shown in Fig. 19 instead of Fig. 6. Fig. 19 is a flowchart showing the operation of the charging device 1 according to the tenth modification of the embodiment.

[0247] The charging device 1 has a resonance capacitor 263 (see FIG. 13) instead of the capacitor 4 (see FIG. 3).

[0248] After steps S1 to S8 are performed in the same manner as in the embodiment, the controller 17 performs fine adjustment processing based on the control of the resonance capacitor 263 (S47i). As the fine adjustment processing based on the control of the resonance capacitor 263, the controller 17 performs processing equivalent to S101 to S102 in FIG.

[0249] For example, the controller 17 acquires a parameter related to a coupling coefficient by using the communication established with the object to be charged 100 (S101). The parameter related to the coupling coefficient is information related to the coupling coefficient of the electromagnetic coupling between the receiving coil 103 and the transmitting coil 3, and is an example of communication information. The parameter related to the coupling coefficient may be the value of the coupling coefficient itself, or may be various values ​​required for calculating the coupling coefficient. In other words, the calculation of the coupling coefficient may be performed in the object to be charged 100 or in the charging device 1.

[0250] The controller 17 switches the capacitance of the resonance capacitor 263 so as to maximize the coupling coefficient (S102). For example, the controller 17 switches which of the multiple capacitors 2631 to activate by controlling the on / off of each of the multiple switches 2633 (see FIG. 13).

[0251] After S47i, SI0 is performed in the same manner as in the embodiment. Then, the controller 17 performs fine adjustment processing based on the change in the relative coil position (S49i). The controller 17 performs processing equivalent to S201 to S210 in FIG. 17 as the fine adjustment processing based on the change in the relative coil position.

[0252] For example, the controller 17 sets the X direction as the movement direction of the power transmitting coil 3 (S201).

[0253] The controller 17 moves the power transmitting coil 3 by "+1" step (S202). In addition, the controller 17 acquires information on the amount of received power from the object to be charged 100 (S203).

[0254] The controller 17 determines whether the received power has decreased (S204). If the received power has not decreased (S204: No), the process returns to S202.

[0255] If the received power has decreased (S204: Yes), the controller 17 moves the power transmitting coil 3 by "-1" step (S205). The controller 17 acquires information on the amount of received power from the object to be charged 100 in the same manner as in S203 (S206). The controller 17 determines whether the received power has decreased (S207) in the same manner as in S204. If the received power has not decreased (S207: No), the process returns to S205. In this way, the controller 17 repeats the same processes as in S202 to S204 with the moving direction of the power transmitting coil 3 reversed.

[0256] If the received power decreases even after the moving direction is reversed (S207: Yes), the controller 17 moves the power transmitting coil 3 back by one step (S208).

[0257] The controller 17 determines whether the processing for all directions is complete (S209). If the processing for all directions is not complete (S209: No), the controller 17 sets the Y direction as the movement direction for the movement of the power transmitting coil 3 (S210). Thereafter, the process returns to S202, and S202 to S208 for the Y direction are performed in the same manner as S202 to S208 for the X direction. Then, if the processing for all directions is complete (S209: Yes), the process ends.

[0258] After S49i, SI0 is performed in the same manner as in the embodiment.

[0259] In this way, in the charging device 1, by performing fine-tuning processing based on the control of the resonant capacitor 263 after S8 and performing fine-tuning processing based on a change in the relative position of the coil after S9, the driving frequency can be made closer to the resonant frequency of the object to be charged 100, and the efficiency of power transmission can be further improved.

[0260] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope of the invention and its equivalents described in the claims, as well as in the scope and spirit of the invention.

[0261] (Additional Note) [Appendix 1] A housing having a placement surface on which an object to be charged having a first coil can be placed; a second coil accommodated in the housing at a position corresponding to the first coil; a controller that acquires a parameter indicating a distance between the first coil and the second coil, and inductively couples the first coil and the second coil when the distance indicated by the parameter is below a distance threshold, and resonantly couples the first coil and the second coil when the distance indicated by the parameter exceeds the distance threshold; A charging device comprising: [Appendix 2] the parameters include a coupling coefficient indicating a degree of inductive coupling between the first coil and the second coil; The controller inductively couples the first coil and the second coil when the coupling coefficient exceeds a coefficient threshold corresponding to the distance threshold, and resonantly couples the first coil and the second coil when the coupling coefficient is below the coefficient threshold. 2. A charging device as described in claim 1. [Appendix 3] a drive circuit to which the second coil is connected and capable of driving the second coil; the object to be charged further includes a first capacitor to which the first coil is connected, When the distance indicated by the parameter exceeds the distance threshold, the controller adjusts a drive frequency of the drive circuit to a resonant frequency corresponding to the first coil and the first capacitor to resonantly couple the first coil and the second coil. 2. A charging device as described in claim 1. [Appendix 4] a drive circuit to which the second coil is connected and capable of driving the second coil; a first voltage detection circuit connected to an input side of the drive circuit and configured to detect a first voltage on the input side of the drive circuit; a second voltage detection circuit connected to an output side of the drive circuit and configured to detect a second voltage on the output side of the drive circuit; Further equipped with The controller determines the coupling coefficient in response to the first voltage and the second voltage. 6. A charging device as described in claim 2. [Appendix 5] When the distance indicated by the parameter exceeds the distance threshold, the controller communicates with the object to be charged via the drive circuit and the second coil to obtain information regarding a value of the first coil and a value of the first capacitor, and calculates a resonant frequency according to the value of the first coil and the value of the first capacitor indicated by the information. 4. A charging device as described in claim 3. [Appendix 6] A plurality of detector coils housed in the housing and arranged along the arrangement surface; a moving mechanism that changes a relative position between the second coil and the first coil; Further equipped with the controller controls the plurality of detector coils to detect a position of the first coil, controls the second coil to communicate with the first coil, controls the moving mechanism to perform a first adjustment to change the relative position to a first relative position based on the detected position of the first coil, and controls the moving mechanism to perform a second adjustment to change the first relative position to a second relative position based on communication information received from the first coil through the communication; the first relative position is a position where a center position of the first coil and a center position of the second coil coincide with each other; The second relative position is a position different from the first relative position, and is a position where a center position of the first coil does not match a center position of the second coil. 2. A charging device as described in claim 1. [Appendix 7] a support portion that supports the object to be charged on the placement surface to thereby define a relative position between the second coil and the first coil to a first relative position; a moving mechanism that changes a relative position between the second coil and the first coil; Further equipped with the controller controls the second coil to communicate with the first coil, and controls the moving mechanism to perform a second adjustment to change the first relative position to a second relative position based on communication information received from the first coil through the communication; the first relative position is a position where a center position of the first coil and a center position of the second coil coincide with each other; The second relative position is a position different from the first relative position, and is a position where a center position of the first coil does not match a center position of the second coil. 2. A charging device as described in claim 1. [Appendix 8] The communication information is information regarding the amount of power received by the first coil, which is related to the power wirelessly transmitted from the second coil. 8. The charging device according to claim 6 or 7. [Appendix 9] The second relative position is a peak position of power efficiency, which is a ratio of the amount of power received by the first coil to the amount of power wirelessly transmitted from the second coil. 9. A charging device as described in claim 8. [Appendix 10] The communication information further includes information regarding a coupling coefficient of electromagnetic coupling between the first coil and the second coil. 9. A charging device as described in claim 8. [Appendix 11] The coil further includes a resonance capacitor electrically connected to the second coil and configured to have a variable capacitance. the controller performs a third adjustment, prior to the second adjustment, in which a capacitance of the resonance capacitor is controlled based on information about the coupling coefficient to adjust a resonance frequency of power wirelessly transmitted from the second coil; 11. The charging device of claim 10. [Appendix 12] The controller starts charge control at the first relative position. 8. The charging device according to claim 6 or 7. [Appendix 13] A housing having a placement surface on which an object to be charged can be placed, the object having a first coil and a first capacitor to which the first coil is connected; a second coil accommodated in the housing at a position corresponding to the first coil; a drive circuit to which the second coil is connected; A controller that searches for a resonance frequency corresponding to the first coil and the first capacitor while communicating with the object to be charged via the drive circuit and the second coil, and adjusts the drive frequency of the drive circuit to the searched resonance frequency to resonate and couple the first coil and the second coil; A charging device comprising: [Appendix 14] Acquiring a parameter indicating a distance between a first coil in an object to be charged placed on a placement surface of a housing and a second coil accommodated in a position corresponding to the first coil in the housing; resonantly coupling the first coil and the second coil when the distance indicated by the parameter exceeds a distance threshold; Including charging methods. [Appendix 15] the parameters include a coupling coefficient between the first coil and the second coil; The resonant coupling includes: resonantly coupling the first coil and the second coil when the coupling coefficient is below a coefficient threshold corresponding to the distance threshold. Charging method as described in Appendix 14. [Appendix 16] detecting a position of the first coil by controlling a plurality of detector coils housed in the housing and arranged along the placement surface; controlling the second coil to communicate with the first coil; performing a first adjustment to change the relative position between the second coil and the first coil to a first relative position where a center position of the first coil coincides with a center position of the second coil based on the detected position of the first coil by controlling a moving mechanism that changes the relative position between the second coil and the second coil; performing a second adjustment by controlling the moving mechanism to change the first relative position to a second relative position different from the first relative position and in which a central position of the first coil does not coincide with a central position of the second coil based on communication information received from the first coil through the communication; Also includes Charging method as described in Appendix 14. [Appendix 17] supporting the object to be charged on the placement surface with a support portion, so that a relative position between the second coil and the first coil is defined as a first relative position where a center position of the first coil coincides with a center position of the second coil, and controlling the second coil to communicate with the first coil; performing a second adjustment to change the first relative position to a second relative position different from the first relative position and in which a center position of the first coil does not coincide with a center position of the second coil based on communication information received from the first coil through the communication by controlling a moving mechanism that changes a relative position between the second coil and the first coil; Also includes Charging method as described in Appendix 14. [Appendix 18] A charging object is arranged on a placement surface of a housing and has a first coil and a first capacitor connected to the first coil. A second coil is accommodated in a position corresponding to the first coil in the housing, and the second coil is driven by a drive circuit to communicate with the charging object, and a resonant frequency corresponding to the first coil and the first capacitor is searched for; Adjusting a drive frequency of the drive circuit to the searched resonant frequency to resonantly couple the first coil and the second coil; Including charging methods. (References) [Reference Note 1] A charging device that wirelessly charges a terminal device having a power receiving coil that is disposed on a placement surface and receives wirelessly transmitted power, A power transmission coil that transmits power to the terminal device; a plurality of detector coils for detecting the position of the power receiving coil of the terminal device on the placement surface; a moving mechanism that changes a relative position between the power transmitting coil and the power receiving coil; Controlling the plurality of detector coils to detect the position of the receiving coil; Controlling the power transmitting coil to communicate with the power receiving coil; performing a first adjustment to change the relative position to a first relative position based on the detected position of the power receiving coil by controlling the moving mechanism; performing a second adjustment by controlling the moving mechanism to change the first relative position to a second relative position based on the communication information received from the power receiving coil through the communication; A controller, the first relative position is a position where a center position of the power receiving coil and a center position of the power transmitting coil coincide with each other; The second relative position is a position different from the first relative position, and is a position where a center position of the power receiving coil and a center position of the power transmitting coil do not match. Charging device. [Reference Note 2] A charging device that wirelessly charges a terminal device having a power receiving coil that is disposed on a placement surface and receives wirelessly transmitted power, A power transmission coil that transmits power to the terminal device; a support portion that supports the terminal device on the placement surface to define a relative position between the power transmitting coil and the power receiving coil at a first relative position; a moving mechanism that changes a relative position between the power transmitting coil and the power receiving coil; Controlling the power transmitting coil to communicate with the power receiving coil; performing a second adjustment by controlling the moving mechanism to change the first relative position to a second relative position based on the communication information received from the power receiving coil through the communication; A controller, the first relative position is a position where a center position of the power receiving coil and a center position of the power transmitting coil coincide with each other; The second relative position is a position different from the first relative position, and is a position where a center position of the power receiving coil and a center position of the power transmitting coil do not match. Charging device. [Reference Note 3] The communication information is information regarding the amount of power received by the power receiving coil, regarding the power wirelessly transmitted from the power transmitting coil. 2. A charging device according to claim 1 or 2. [Reference Note 4] The second relative position is a peak position of power efficiency, which is a ratio of the amount of power received by the power receiving coil to the amount of power wirelessly transmitted from the power transmitting coil. Charging device as described in Appendix 3. [Reference Note 5] The communication information further includes information regarding a coupling coefficient of electromagnetic coupling between the power receiving coil and the power transmitting coil. Charging device as described in Appendix 3. [Reference Note 6] The power transmission device further includes a resonance capacitor electrically connected to the power transmission coil and configured to have a variable capacitance. the controller performs a third adjustment prior to the second adjustment in which a capacitance of the resonance capacitor is controlled based on information about the coupling coefficient to adjust a resonance frequency of power wirelessly transmitted from the power transmitting coil. Charging device as described in Appendix 5. [Reference Note 7] The controller starts charge control at the first relative position. 2. A charging device according to claim 1 or 2. [Reference Note 8] A method for controlling a charging device, comprising: a power transmitting coil that transmits power to a terminal device that is placed on a placement surface and has a power receiving coil that receives wirelessly transmitted power; a plurality of detector coils that detect a position of the power receiving coil of the terminal device on the placement surface; and a movement mechanism that changes a relative position between the power transmitting coil and the power receiving coil, the method comprising: detecting a position of the power receiving coil by controlling the plurality of detector coils; Controlling the power transmitting coil to communicate with the power receiving coil; performing a first adjustment of changing the relative position to a first relative position based on the detected position of the power receiving coil by controlling the moving mechanism; performing a second adjustment by controlling the moving mechanism to change the first relative position to a second relative position based on communication information received from the power receiving coil through the communication; the first relative position is a position where a center position of the power receiving coil and a center position of the power transmitting coil coincide with each other; The second relative position is a position different from the first relative position, and is a position where a center position of the power receiving coil and a center position of the power transmitting coil do not match. A method for controlling a charging device. [Reference Note 9] A method for controlling a charging device, comprising: a power transmitting coil that transmits power to a terminal device arranged on a placement surface and has a power receiving coil that receives wirelessly transmitted power; a support unit that supports the terminal device on the placement surface to set a relative position between the power transmitting coil and the power receiving coil to a first relative position; and a movement mechanism that changes the relative position between the power transmitting coil and the power receiving coil, Controlling the power transmitting coil to communicate with the power receiving coil; performing a second adjustment by controlling the moving mechanism to change the first relative position to a second relative position based on communication information received from the power receiving coil through the communication; the first relative position is a position where a center position of the power receiving coil and a center position of the power transmitting coil coincide with each other; The second relative position is a position different from the first relative position, and is a position where a center position of the power receiving coil and a center position of the power transmitting coil do not match. A method for controlling a charging device. [Reference Note 10] The communication information is information regarding the amount of power received by the power receiving coil, regarding the power wirelessly transmitted from the power transmitting coil. A method for controlling a charging device according to Reference Appendix 8 or Reference Appendix 9. [Reference Note 11] The second relative position is a peak position of power efficiency, which is a ratio of the amount of power received by the power receiving coil to the amount of power wirelessly transmitted from the power transmitting coil. A method for controlling a charging device as described in Appendix 10. [Reference Note 12] The communication information further includes information regarding a coupling coefficient of electromagnetic coupling between the power receiving coil and the power transmitting coil. A method for controlling a charging device as described in Appendix 10. [Reference Note 13] the charging device further includes a resonance capacitor electrically connected to the power transmission coil and configured to have a variable capacitance; and performing, prior to the second adjustment, a third adjustment in which a capacitance of the resonance capacitor is controlled based on information about the coupling coefficient to adjust a resonance frequency of power wirelessly transmitted from the power transmitting coil. A method for controlling a charging device as described in Appendix 12. [Reference Note 14] and initiating charge control at the first relative position. A method for controlling a charging device according to Reference Appendix 8 or Reference Appendix 9. [Explanation of symbols]

[0262] 1,210 Charging equipment 2,212 units 3,230 Transmission coil 13 Inverter circuit 17,250 Controllers 100 Charged object 103,234 Receiving coil

Claims

1. A housing having a placement surface on which an object to be charged having a first coil can be placed; a second coil accommodated in the housing at a position corresponding to the first coil; a controller that acquires a parameter indicating a distance between the first coil and the second coil, and inductively couples the first coil and the second coil when the distance indicated by the parameter is below a distance threshold, and resonantly couples the first coil and the second coil when the distance indicated by the parameter exceeds the distance threshold; A charging device comprising:

2. the parameters include a coupling coefficient indicating a degree of inductive coupling between the first coil and the second coil; The controller inductively couples the first coil and the second coil when the coupling coefficient exceeds a coefficient threshold corresponding to the distance threshold, and resonantly couples the first coil and the second coil when the coupling coefficient is below the coefficient threshold. The charging device according to claim 1 .

3. a drive circuit to which the second coil is connected and capable of driving the second coil; The object to be charged further includes a first capacitor to which the first coil is connected, When the distance indicated by the parameter exceeds the distance threshold, the controller adjusts a drive frequency of the drive circuit to a resonant frequency corresponding to the first coil and the first capacitor to resonantly couple the first coil and the second coil. The charging device according to claim 1 .

4. a drive circuit to which the second coil is connected and capable of driving the second coil; a first voltage detection circuit connected to an input side of the drive circuit and configured to detect a first voltage on the input side of the drive circuit; a second voltage detection circuit connected to an output side of the drive circuit and configured to detect a second voltage on the output side of the drive circuit; Further equipped with The controller determines the coupling coefficient in response to the first voltage and the second voltage. The charging device according to claim 2.

5. When the distance indicated by the parameter exceeds the distance threshold, the controller communicates with the object to be charged via the drive circuit and the second coil to obtain information regarding a value of the first coil and a value of the first capacitor, and calculates a resonant frequency according to the value of the first coil and the value of the first capacitor indicated by the information. The charging device according to claim 3.

6. A plurality of detector coils housed in the housing and arranged along the arrangement surface; a moving mechanism that changes a relative position between the second coil and the first coil; Further equipped with the controller controls the plurality of detector coils to detect a position of the first coil, controls the second coil to communicate with the first coil, controls the moving mechanism to perform a first adjustment to change the relative position to a first relative position based on the detected position of the first coil, and controls the moving mechanism to perform a second adjustment to change the first relative position to a second relative position based on communication information received from the first coil through the communication; the first relative position is a position where a center position of the first coil and a center position of the second coil coincide with each other; the second relative position is a position different from the first relative position, and is a position where a center position of the first coil does not coincide with a center position of the second coil; The charging device according to claim 1 .

7. a support portion that supports the object to be charged on the placement surface to thereby define a relative position between the second coil and the first coil at a first relative position; a moving mechanism that changes a relative position between the second coil and the first coil; Further equipped with the controller controls the second coil to communicate with the first coil, and controls the moving mechanism to perform a second adjustment to change the first relative position to a second relative position based on communication information received from the first coil through the communication; the first relative position is a position where a center position of the first coil and a center position of the second coil coincide with each other; the second relative position is a position different from the first relative position, and is a position where a center position of the first coil does not coincide with a center position of the second coil; The charging device according to claim 1 .

8. The communication information is information regarding the amount of power wirelessly transmitted from the second coil and received by the first coil.

8. The charging device according to claim 6 or 7.

9. The second relative position is a peak position of power efficiency, which is a ratio of an amount of power received by the first coil to an amount of power wirelessly transmitted from the second coil. The charging device according to claim 8.

10. The communication information further includes information regarding a coupling coefficient of electromagnetic coupling between the first coil and the second coil. The charging device according to claim 8.

11. A resonance capacitor electrically connected to the second coil and configured to have a variable capacitance is further provided. the controller performs a third adjustment, prior to the second adjustment, in which a capacitance of the resonance capacitor is controlled based on information about the coupling coefficient to adjust a resonance frequency of power wirelessly transmitted from the second coil; The charging device according to claim 10.

12. The controller starts charge control at the first relative position. The charging device according to claim 6 or 7.

13. A housing having a placement surface on which an object to be charged can be placed, the object having a first coil and a first capacitor to which the first coil is connected; a second coil accommodated in the housing at a position corresponding to the first coil; a drive circuit to which the second coil is connected; A controller that searches for a resonance frequency corresponding to the first coil and the first capacitor while communicating with the object to be charged via the drive circuit and the second coil, and adjusts the drive frequency of the drive circuit to the searched resonance frequency to resonantly couple the first coil and the second coil; A charging device comprising:

14. Acquiring a parameter indicating a distance between a first coil in an object to be charged that is placed on a placement surface of a housing and a second coil that is accommodated in a position corresponding to the first coil in the housing; resonantly coupling the first coil and the second coil when the distance indicated by the parameter exceeds a distance threshold; Including charging methods.

15. the parameters include a coupling coefficient between the first coil and the second coil; The resonant coupling includes: resonantly coupling the first coil and the second coil when the coupling coefficient is below a coefficient threshold corresponding to the distance threshold. The charging method according to claim 14.

16. detecting a position of the first coil by controlling a plurality of detector coils housed in the housing and arranged along the placement surface; controlling the second coil to communicate with the first coil; performing a first adjustment to change the relative position between the second coil and the first coil to a first relative position where a center position of the first coil coincides with a center position of the second coil based on the detected position of the first coil by controlling a moving mechanism that changes the relative position between the second coil and the second coil; performing a second adjustment by controlling the moving mechanism to change the first relative position to a second relative position different from the first relative position and in which a central position of the first coil does not coincide with a central position of the second coil based on communication information received from the first coil through the communication; Also includes The charging method according to claim 14.

17. supporting the object to be charged on the placement surface with a support portion, so that a relative position between the second coil and the first coil is defined as a first relative position where a center position of the first coil coincides with a center position of the second coil, and controlling the second coil to communicate with the first coil; performing a second adjustment to change the first relative position to a second relative position different from the first relative position and in which a center position of the first coil does not coincide with a center position of the second coil based on communication information received from the first coil through the communication by controlling a moving mechanism that changes a relative position between the second coil and the first coil; Also includes The charging method according to claim 14.

18. A charging object has a first coil and a first capacitor connected to the first coil, and the charging object is driven by a driving circuit to communicate with the charging object by driving a second coil accommodated in a position corresponding to the first coil in the housing; and searching for a resonance frequency corresponding to the first coil and the first capacitor. Adjusting a drive frequency of the drive circuit to the searched resonant frequency to resonantly couple the first coil and the second coil; Including charging methods.

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