Wireless charger

Abstract

To suppress drop of efficiency of charging of a portable terminal by a wireless charger equipped in a vehicle.SOLUTION: A wireless charger is equipped in a vehicle. The wireless charger has a control unit. The control unit estimates the moving direction of the portable terminal on the wireless charger on the basis of the direction of an acceleration in a case where generation of the acceleration, which is at least a predetermined threshold value in a horizontal direction, was detected during charging of the portable terminal. The control unit further determines the position of a power sending coil on the basis of the estimated moving direction of the portable terminal in the wireless charger.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a wireless charging device mounted on a vehicle. [Background technology]

[0002] Patent Document 1 discloses a contactless charging system. The contactless charging system disclosed in Patent Document 1 includes a driving device and a receiving coil position detection unit. The driving device can move the position of the relay coil. The receiving coil position detection unit detects or estimates the relative position of the passive coil with respect to the transmitting coil. Then, the driving device controls the position of the relay coil based on the relative position of the passive coil with respect to the transmitting coil. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2021-180578 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to suppress a decrease in efficiency of charging a portable terminal by a wireless charging device mounted on a vehicle. [Means for solving the problem]

[0005] The wireless charging device according to the present disclosure comprises: A wireless charging device that is mounted on a vehicle and charges a portable terminal placed on the vehicle, When it is detected that acceleration of a magnitude equal to or greater than a predetermined threshold occurs in a horizontal direction while the portable terminal is being charged, estimating a moving direction of the portable terminal on the wireless charging device based on a direction of the acceleration; determining a position of a power transmitting coil to be energized for charging the portable terminal in the wireless charging device based on the estimated moving direction of the portable terminal; The control unit executes the above. Effect of the Invention

[0006] According to the present disclosure, it is possible to suppress a decrease in efficiency of charging a portable terminal by a wireless charging device mounted on a vehicle. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram for explaining an outline of a charging device according to a first embodiment. [Diagram 2] FIG. 2 is a block diagram for explaining a hardware configuration of the charging device and various devices mounted on the vehicle according to the first embodiment. [Diagram 3] FIG. 3 is a flow of current supply control according to the first embodiment. [Figure 4] FIG. 4 is a flow chart showing a process for acquiring the weight of a mobile terminal according to a modified example of the first embodiment. [Diagram 5] The figure shows a flow of current supply control according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] There is known a wireless charging device that is installed in a vehicle to charge a portable terminal of a passenger. When the portable terminal is to be charged by the wireless charging device, the portable terminal is placed on the wireless charging device. Then, a power transmission coil provided in the wireless charging device and the portable terminal Electromagnetic induction is generated between the power receiving coil provided in the power receiving portion and the power receiving coil provided in the power receiving portion, thereby generating electric power in the portable terminal and charging the battery of the portable terminal.

[0009] However, acceleration occurs while the vehicle is traveling. If horizontal acceleration occurs while the mobile terminal is being charged by the wireless charging device, the mobile terminal placed on the wireless charging device may move. If the mobile terminal moves on the wireless charging device, the position of the power receiving coil of the mobile terminal relative to the power transmitting coil of the wireless charging device may shift, reducing the amount of power generated by electromagnetic induction in the mobile terminal, and as a result, there is a risk of a decrease in the charging efficiency of the mobile terminal. The present disclosure has been made in consideration of such problems.

[0010] The wireless charging device according to the present disclosure is configured to be capable of changing the position of a power transmitting coil. More specifically, for example, the wireless charging device may have a plurality of power transmitting coils. Then, while charging the mobile terminal, the position of the power transmitting coil used for charging the mobile terminal may be changed by changing the power transmitting coil to be energized. Also, in the wireless charging device, at least one power transmitting coil may be provided so as to be movable. Then, while charging the mobile terminal, the position of the power transmitting coil may be changed by moving the power transmitting coil itself that is energized.

[0011] The wireless charging device according to the present disclosure also includes a control unit. When the control unit detects that acceleration of a magnitude equal to or greater than a predetermined threshold has occurred in the horizontal direction while the mobile terminal is being charged, the control unit estimates the direction of movement of the mobile terminal on the wireless charging device based on the direction of the acceleration. Here, the predetermined threshold may be determined as a lower limit value of the magnitude of acceleration at which the mobile terminal may move on the wireless charging device due to the occurrence of acceleration. According to this, when acceleration of a magnitude equal to or greater than the predetermined threshold has occurred in the horizontal direction in a vehicle while the mobile terminal is being charged by the wireless charging device, it can be determined that the mobile terminal may have moved on the wireless charging device.

[0012] Furthermore, the control unit determines the position of the power transmitting coil to be energized for charging the portable terminal in the wireless charging device based on the estimated direction of movement of the portable terminal. That is, the control unit changes the position of the power transmitting coil so as to follow the movement of the portable terminal on the wireless charging device.

[0013] According to this, even if the portable terminal being charged moves due to acceleration generated in the vehicle while the vehicle is moving, the positional relationship between the power transmitting coil of the wireless charging device and the power receiving coil of the portable terminal can be quickly corrected to an appropriate position, thereby suppressing a decrease in the efficiency of charging the portable terminal by the wireless charging device mounted on the vehicle.

[0014] Hereinafter, specific embodiments of the present disclosure will be described with reference to the drawings. The dimensions, materials, shapes, and relative positions of the components described in the present embodiments are not intended to limit the technical scope of the present disclosure unless otherwise specified.

[0015] First Embodiment 1 is a diagram for explaining an outline of a charging device according to this embodiment. The charging device 100 is a wireless charging device mounted in a vehicle cabin of a vehicle 10. For example, the charging device 100 may be installed on a dashboard or a center console of the vehicle 10. When a portable terminal 200 carried by a passenger (a driver or a passenger of the vehicle 10) is placed on a placement surface of the charging device 100, the charging device 100 wirelessly charges the portable terminal 200. The portable terminal 200 may be, for example, a smartphone, a tablet terminal, a wearable terminal, or the like.

[0016] The charging device 100 is driven by an on-board battery of the vehicle 10 as a power source. The charging device 100 charges the mobile terminal 200 by an electromagnetic induction method. Specifically, the mobile terminal 200 has a built-in power receiving coil 200a. Meanwhile, the charging device 100 has a plurality of (four in FIG. 1 ) built-in power transmitting coils 100a. When current is applied to any one of the plurality of power transmitting coils 100a in the charging device 100, electromagnetic induction occurs between the power transmitting coil 100a that has been applied and the power receiving coil 200a of the mobile terminal 200. As a result, power is generated in the mobile terminal 200, and the battery of the mobile terminal 200 is charged.

[0017] Here, the charging device 100 is provided with a plurality of power transmitting coils 100a as described above. Then, a power transmitting coil 100a to be energized is selected from the plurality of power transmitting coils 100a according to the position of the mobile terminal 200 on the placement surface of the charging device 100. That is, the power transmitting coil 100a located at a position facing the power receiving coil 200a of the mobile terminal 200 in the charging device 100 is selected and energized. As a result, electricity is applied to the power transmitting coil 100a located at a position where electromagnetic induction is likely to occur between the power transmitting coil 100a and the power receiving coil 200a of the mobile terminal 200. As a result, the mobile terminal 200 can be efficiently charged.

[0018] However, horizontal acceleration may occur while the vehicle 10 is traveling. When the mobile terminal 200 is placed on the placement surface of the charging device 100, that is, while the mobile terminal 200 is being charged, if a relatively large acceleration occurs in the horizontal direction, the mobile terminal 200 may move on the placement surface. As a result, if the relative positional relationship between the power transmitting coil 100a to which current is applied in the charging device 100 and the power receiving coil 200a of the mobile terminal 200 is displaced, the amount of power generated in the mobile terminal 200 may decrease, and the charging efficiency of the mobile terminal 200 may decrease.

[0019] Therefore, in this embodiment, the charging device 100 changes the power transmitting coil 100a to be energized in response to the movement of the portable terminal 200 being charged on the placement surface. At this time, the charging device 100 estimates the moving direction of the portable terminal 200 and the amount of movement of the portable terminal 200 in the moving direction based on the direction of horizontal acceleration generated in the vehicle 10 and the magnitude of the acceleration.

[0020] (Hardware configuration of charging device) 2 is a block diagram for explaining the hardware configuration of the charging device and various devices mounted on the vehicle according to the present embodiment. The charging device 100 includes a control unit 110, a storage unit 120, a charging circuit 130, an in-vehicle communication module 140, and a communication module 150 in addition to the multiple power transmitting coils 100a described above.

[0021] The vehicle 10 also includes a vehicle ECU 11, an acceleration sensor 12, and a vehicle battery 13. The vehicle ECU 11 is an ECU (Electric Central Unit) that controls the behavior of the vehicle 10 based on detection values ​​of various sensors provided in the vehicle 10. The acceleration sensor 12 detects the vehicle 10's speed and direction. 0. The acceleration sensor 12 detects acceleration occurring in three axial directions, namely, the X-axis direction, the Y-axis direction, and the Z-axis direction, in the vehicle 10. The detection values ​​of the acceleration sensor 12 are input to the vehicle ECU 11. The vehicle battery 13 is a power source that supplies power to various devices provided in the vehicle 10, such as the vehicle ECU 11 and the acceleration sensor 12.

[0022] The control unit 110 has a function of performing arithmetic processing for controlling the charging device 100. The control unit 110 includes a processor such as a CPU (Central Processing Unit), a main storage device such as a RAM (Random Access Memory), and an auxiliary storage device such as a ROM (Read Only Memory). The CPU is an example of a processor resource. The RAM and ROM are examples of a memory resource. The control unit 110 controls the CPU based on various programs and various data. Any information processing can be executed. However, some or all of the functions of the control unit 110 may be realized by a hardware circuit such as an ASIC or an FPGA. The storage unit 120 is configured by any storage device such as a RAM, a ROM, or a flash memory. The storage unit 120 stores programs executed by the control unit 110 and various data used for executing the programs.

[0023] The charging circuit 130 is a circuit that converts the DC power supplied from the vehicle battery 13 into AC power of an appropriate amplitude and frequency, and supplies the converted AC power to the transmitting coil 100a to be energized.The charging circuit 130 includes, for example, a DC-DC converter, an inverter, etc.

[0024] The in-vehicle communication module 140 is an interface for the charging device 100 to communicate with other devices provided in the vehicle 10 using a predetermined in-vehicle communication standard. Examples of the predetermined in-vehicle communication standard include CAN (Controller Area Network) and LIN (Local Interconnect Network). The charging device 100 communicates with the in-vehicle communication module 140 via the in-vehicle communication standard. 0. For example, the charging device 100 periodically receives information on the direction and magnitude of horizontal acceleration occurring in the vehicle 10, which is calculated by the vehicle ECU 11 based on the detection value of the acceleration sensor 12, from the vehicle ECU 11 at a predetermined period.

[0025] The communication module 150 is an interface for the charging device 100 to directly communicate with the mobile terminal 200 placed on the placement surface using a predetermined short-range wireless communication standard. Examples of the predetermined short-range wireless communication standard include the Bluetooth (registered trademark) Low Energy standard and WiFi (registered trademark). The charging device 100 communicates with the mobile terminal 200 being charged via the communication module 150. For example, the charging device 100 periodically receives the status of the mobile terminal 200, including the power (power generation amount) generated by electromagnetic induction in the mobile terminal 200, from the mobile terminal 200 at a predetermined period.

[0026] The mobile terminal 200 includes a processor such as a CPU (Central Processing Unit), an RA, The portable terminal 200 has a main storage device such as a Random Access Memory (M) and an auxiliary storage device such as a Read Only Memory (ROM). Furthermore, the portable terminal 200 has a communication module that uses a standard similar to the short-range wireless communication standard used by the communication module 150 of the charging device 100.

[0027] (Power supply control flow) Next, a flow of energization control executed in the charging device 100 will be described with reference to Fig. 3. Fig. 3 shows a flow of energization control according to the present embodiment. This flow is executed by the control unit 110 when the mobile terminal 200 is placed on the placement surface of the charging device 100, that is, while the mobile terminal 200 is being charged by the charging device 100.

[0028] In this flow, first, in S101, the direction and magnitude Va of the acceleration in the horizontal direction occurring in the vehicle 10 are received from the vehicle ECU 11. Next, in S102, it is determined whether or not the magnitude Va of the acceleration received in S101 (i.e., the absolute value of the acceleration) is equal to or greater than a predetermined threshold value Va0. Here, the predetermined threshold value Va0 may be determined as a lower limit value of the magnitude of the acceleration at which the mobile terminal 200 may move on the charging device 100 due to the occurrence of the acceleration. Note that the charging device 100 may be provided with an acceleration sensor capable of detecting the direction and magnitude of the acceleration in the horizontal direction. In this case, the charging device 100 can grasp the acceleration occurring in the vehicle 10 without communicating with the vehicle ECU 11.

[0029] If the determination in S102 is negative, that is, if the magnitude of acceleration Va is less than a predetermined threshold value Va0, it can be assumed that the mobile terminal 200 is not moving on the charging device 100. In this case, the execution of this flow is temporarily terminated.

[0030] On the other hand, if the determination in S102 is positive, that is, if the magnitude of acceleration Va is equal to or greater than the predetermined threshold value Va0, it can be assumed that the portable terminal 200 has moved on the charging device 100. In this case, the process of S103 is then executed. In S103, the moving direction of the portable terminal 200 on the charging device 100 is estimated based on the direction of the acceleration received in S101.

[0031] Next, in S104, the amount of movement of the portable terminal 200 on the charging device 100 is estimated based on the magnitude of the acceleration received in S101. Here, it is estimated that the greater the magnitude of the acceleration received in S101, the greater the amount of movement of the portable terminal 200 on the charging device 100.

[0032] Next, in S105, a power transmitting coil 100a to be energized is selected from among the multiple power transmitting coils 100a based on the moving direction and the moving amount of the mobile terminal 200 estimated in S103. At this time, if it is determined that the power transmitting coil 100a located opposite the power receiving coil 200a of the mobile terminal 200 due to the movement of the mobile terminal 200 is different from the power transmitting coil 100a before the acceleration occurs, the power transmitting coil 100a to be energized is changed. On the other hand, if the power transmitting coil 100a located opposite the power receiving coil 200a of the mobile terminal 200 is the same as the power transmitting coil 100a before the acceleration occurs even after the mobile terminal 200 moves, the same power transmitting coil 100a continues to be energized. After that, the execution of this flow is temporarily terminated.

[0033] According to the above flow, even if the position of the power receiving coil 200a of the mobile terminal 200 relative to the power transmitting coil 100a energized in the charging device 100 shifts due to acceleration occurring in the vehicle 10, the power transmitting coil 100a to be energized can be quickly corrected to an appropriate coil. That is, the position of the power transmitting coil 100a to which power is applied in the charging device 100 for charging the mobile terminal 200 can be quickly changed so as to follow the movement of the mobile terminal 200. Therefore, a decrease in efficiency of charging the mobile terminal 200 by the charging device 100 can be suppressed.

[0034] (Modification) Next, a modified example of this embodiment will be described. As described above, when a relatively large acceleration occurs in the horizontal direction in the vehicle 10 while the portable terminal 200 is being charged, the portable terminal 200 may move on the charging device 100. At this time, even if the magnitude of the acceleration is the same, the amount of movement of the portable terminal 200 may change depending on the weight of the portable terminal 200. Therefore, in this modified example, the control unit 110 of the charging device 100 estimates the amount of movement of the portable terminal 200 on the charging device 100 based on not only the magnitude of the acceleration in the horizontal direction but also the weight of the portable terminal 200.

[0035] More specifically, in this modification, a database (hereinafter referred to as a "portable terminal database") in which information regarding the weight of each model of portable terminal that can be charged is input is stored in storage unit 120 of charging device 100. Furthermore, model information indicating the model of portable terminal 200 placed on charging device 100 is transmitted from portable terminal 200 to charging device 100. Then, when portable terminal 200 is placed on charging device 100, control unit 110 executes a process for acquiring the weight of portable terminal 200.

[0036] 4 is a flow chart showing a process for acquiring the weight of a portable terminal according to this modification. This flow is executed by the control unit 110 when the portable terminal 200 is placed on the placement surface of the charging device 100.

[0037] In this flow, first, in S201, model information of the mobile terminal 200 transmitted from the mobile terminal 200 is received. Next, in S202, the weight of the mobile terminal 200 corresponding to the model information received in S201 is extracted from the mobile terminal database. Next, in S203, the weight of the mobile terminal 200 currently placed on the charging device 100 extracted in S202 is stored in the storage unit 120. Thereafter, the execution of this flow is temporarily terminated. Note that the weight of the mobile terminal 200 stored in the storage unit 120 is deleted from the storage unit 120 when the mobile terminal 200 is removed from the charging device 100.

[0038] In this modification, when control unit 110 executes the process of S104 in the power supply control flow shown in FIG. 3, the weight of mobile terminal 200 is acquired from storage unit 120. Control unit 110 then estimates the amount of movement of mobile terminal 200 based on the magnitude of the horizontal acceleration and the weight of mobile terminal 200.

[0039] According to this modification, it is possible to estimate with higher accuracy the amount of movement of the mobile terminal 200 on the charging device 100 caused by horizontal acceleration of the vehicle 10. This makes it possible to more appropriately select the power transmitting coil 100a to be energized.

[0040] <Second embodiment> In this embodiment, the configurations of the charging device 100 and the mobile terminal 200 are similar to those of the first embodiment. Also in this embodiment, when horizontal acceleration occurs in the vehicle 10 while the mobile terminal 200 is being charged, the moving direction and the moving amount of the mobile terminal 200 are estimated. Then, based on the estimated moving direction and the moving amount of the mobile terminal 200, the charging device 100 selects one of the multiple power transmitting coils 100a to be energized. However, in this embodiment, when horizontal acceleration occurs in the vehicle 10 while the mobile terminal 200 is being charged, unlike the first embodiment, the moving amount of the mobile terminal 200 is estimated based on the amount of change in the amount of power generation in the mobile terminal 200.

[0041] More specifically, charging device 100 periodically receives information on the amount of power generated in portable terminal 200 at a predetermined cycle while portable terminal 200 is being charged. Then, when acceleration of a magnitude equal to or greater than a predetermined threshold value Va0 occurs in vehicle 10 in the horizontal direction while portable terminal 200 is being charged, control unit 110 of charging device 100 calculates the amount of change in the amount of power generated in portable terminal 200 being charged before and after the acceleration occurs.

[0042] As described above, when the relative positional relationship between the power transmitting coil 100a energized in the charging device 100 and the power receiving coil 200a of the mobile terminal 200 is shifted during charging of the mobile terminal 200, the amount of power generated in the mobile terminal 200 decreases. At this time, for example, if the position of the power receiving coil 200a relative to the power transmitting coil 100a energized is a position where the amount of power generated in the mobile terminal 200 is maximum before the occurrence of acceleration, the greater the amount of shift in the relative positional relationship between the coils 100a, 200a after the occurrence of acceleration, the greater the amount of reduction in the amount of power generated in the mobile terminal 200. Therefore, the amount of movement of the mobile terminal 200 can be calculated based on the amount of change in the amount of power generated in the mobile terminal 200 before and after the occurrence of acceleration.

[0043] (Power supply control flow) Hereinafter, a flow of energization control executed in the charging device 100 according to this embodiment will be described with reference to FIG. 5. FIG. 5 shows the flow of energization control according to this embodiment. This flow is executed by the control unit 110 when the mobile terminal 200 is placed on the placement surface of the charging device 100, that is, while the mobile terminal 200 is being charged by the charging device 100. Note that this flow is obtained by replacing S104 of the energization control flow according to the first embodiment shown in FIG. 3 with S304 and S305. Therefore, hereinafter, S304 and S305 will be referred to as the flow of energization control. The processing in step 1 will be described, and the processing in other steps will be omitted.

[0044] In this flow, the process of S304 is executed after S103. In S103, the amount of change dPt in the amount of power generated in the mobile terminal 200 before and after the occurrence of acceleration equal to or greater than a predetermined threshold value Va0 is calculated. At this time, the control unit 110 calculates the amount of change dPt in the amount of power generated from the amount of power generated received from the mobile terminal 200 immediately before the occurrence of the acceleration and the amount of power generated from the mobile terminal 200 immediately after the occurrence of the acceleration.

[0045] Next, in S305, the amount of movement of the portable terminal 200 on the charging device 100 is estimated based on the amount of change dPt in the amount of power generation in the portable terminal 200 calculated in S304. Here, it is estimated that the greater the amount of decrease in the amount of power generation in the portable terminal 200, the greater the amount of movement of the portable terminal 200 on the charging device 100. After S305, the process of S105 is executed.

[0046] In this embodiment, the magnitude Va of the acceleration in the horizontal direction generated in the vehicle 10 is received in S101. Then, the control unit 110 may estimate the amount of movement of the mobile terminal 200 on the charging device 100 based on the magnitude Va of the acceleration and the amount of change dPt in the amount of power generation in the mobile terminal 200.

[0047] Even with the above flow, even if the position of the receiving coil 200a of the mobile terminal 200 relative to the transmitting coil 100a to which current is being applied in the charging device 100 shifts due to acceleration occurring in the vehicle 10, the transmitting coil 100a to be energized can be quickly corrected to an appropriate coil.

[0048] In the first and second embodiments, the charging device 100 includes a plurality of power transmitting coils 100a. In the charging device 100, the position of the power transmitting coil 100a used to charge the mobile terminal 200 is changed by changing the power transmitting coil 100a to which current is applied. However, the configuration of the charging device according to the present disclosure is not limited to such a configuration including a plurality of power transmitting coils. For example, the charging device 100 may be configured to have one power transmitting coil 100a that is configured to be movable in the charging device 100. In this case, in the charging device 100, the control unit 110 controls the position of the power transmitting coil 100a by moving the power transmitting coil 10a itself. In this case, the position of the power transmitting coil 100a itself that is being energized is changed, and the position of the power transmitting coil 100a used to charge the mobile terminal 200 is changed.

[0049] <Other embodiments> The above embodiment is merely an example, and the present disclosure may be modified as appropriate without departing from the spirit and scope of the present disclosure. Furthermore, the processes and means described in the present disclosure may be freely combined and implemented as long as no technical contradiction occurs.

[0050] Furthermore, a process described as being performed by one device may be shared and executed by multiple devices. Alternatively, a process described as being performed by different devices may be executed by one device. In a computer system, the hardware configuration (server configuration) by which each function is realized can be flexibly changed.

[0051] The present disclosure can also be realized by supplying a computer program implementing the functions described in the above embodiments to a computer, and having one or more processors of the computer read and execute the program. Such a computer program may be provided to the computer by a non-transitory computer-readable storage medium connectable to the system bus of the computer, or may be provided to the computer via a network. Non-transitory computer-readable storage media may be, for example, a magnetic disk (floppy disk (registered The term includes any type of medium suitable for storing electronic instructions, such as any type of disk, such as a hard disk (HDD), optical disk (CD-ROM, DVD disk, Blu-ray disk, etc.), read-only memory (ROM), random-access memory (RAM), EPROM, EEPROM, magnetic card, flash memory, or optical card. [Explanation of symbols]

[0052] 10. Vehicle 11. Vehicle ECU 13. Vehicle battery 12 Acceleration sensor 100...Charging device 100a··Transmission coil 110 Control unit 120...Storage section 130...Charging circuit 140 In-vehicle communication module 150··Communication module 200 Mobile terminals 200a Receiving coil

Claims

1. A wireless charging device that is mounted on a vehicle and charges a portable terminal placed on the vehicle, When it is detected that acceleration of a magnitude equal to or greater than a predetermined threshold occurs in a horizontal direction while the portable terminal is being charged, estimating a moving direction of the portable terminal on the wireless charging device based on a direction of the acceleration; determining a position of a power transmitting coil to be energized for charging the portable terminal in the wireless charging device based on the estimated moving direction of the portable terminal; A wireless charging device comprising a control unit that executes the above.

2. the control unit further executes, when it is detected during charging of the portable terminal that acceleration equal to or greater than the predetermined threshold occurs in a horizontal direction, estimating a movement amount of the portable terminal on the wireless charging device based on a magnitude of the acceleration; The control unit determines a position of the power transmitting coil based on the estimated moving direction of the portable terminal and the estimated moving amount of the portable terminal. The wireless charging device according to claim 1 .

3. The control unit is The method further includes obtaining a weight of the mobile device during charging; The control unit estimates a movement amount of the portable terminal on the wireless charging device based on a magnitude of acceleration and a weight of the portable terminal. The wireless charging device according to claim 2 .

4. The control unit further executes receiving model information of the portable terminal from the portable terminal being charged; The control unit acquires a weight of the mobile terminal corresponding to the received model information of the mobile terminal. The wireless charging device according to claim 3 .

5. The control unit is When it is detected during charging of the portable terminal that acceleration equal to or greater than the predetermined threshold has occurred in a horizontal direction, the method further executes estimating an amount of movement of the portable terminal on the wireless charging device based on an amount of change in an amount of power generated in the portable terminal during charging before and after the occurrence of the acceleration; The control unit determines a position of the power transmitting coil based on the estimated moving direction of the portable terminal and the estimated moving amount of the portable terminal. The wireless charging device according to claim 1 .

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