Wireless power supply

Abstract

Even if there is already a terminal receiving power, the position of a newly placed terminal will be reliably detected. [Solution] The wireless power supply device comprises a plurality of power transmission coils, a plurality of first detection coils arranged in a plurality of rows along a first direction, a plurality of second detection coils arranged in a plurality of rows along a second direction intersecting the first direction, a position detection device that outputs a pulse signal for position detection to the detection coils and detects the position of the receiving coil of a powered device placed on a predetermined charging surface based on the detection voltages in the first and second detection coils, a power transmission coil moving device that moves the power transmission coil to a position opposite to the receiving coil detected by the position detection device, and a power supply unit. The position detection device, when power is already being supplied via any of the power transmission coils, invalidates and excludes from detection the first and second detection coils and the receiving coils located within a predetermined distance from the mounting position of the receiving coil to which power is being supplied.

Description

Technical Field

[0001] The present disclosure relates to a wireless power supply device.

Background Art

[0002] In recent years, as Qi-compatible terminals charged by a wireless charging device compliant with the Qi standard, which is a unified standard for wireless charging, have expanded to products other than smartphones such as earphones, mice, tablets, etc., it has become common for a person to possess a plurality of Qi-compatible terminals. Therefore, when attempting to charge these Qi-compatible terminals in an environment such as inside a vehicle, on a bullet train, in a restaurant, etc., a charging stand with a larger charging area and capable of charging a plurality of Qi-compatible terminals with a single charging stand is desired rather than a conventional charging stand specialized for smartphones.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in a charging stand capable of charging a plurality of terminals with a single charging stand as described above, a terminal detection coil is provided to detect that a terminal has been placed and the placement position. However, when charging is already being performed on a terminal, there is a risk that it may be affected by the magnetic field due to charging and the position of a newly placed terminal cannot be accurately detected.

[0005] In view of the above problems, an object of the present invention is to provide a wireless power supply device capable of reliably detecting the position of a newly placed terminal even in a state where a terminal that is already supplying power exists.

Means for Solving the Problems

[0006] The wireless power supply device of the embodiment comprises: a plurality of power transmission coils; a plurality of first detection coils arranged in a plurality of rows along a first direction; a plurality of second detection coils arranged in a plurality of rows along a second direction intersecting the first direction; a position detection device that outputs position detection pulse signals to the first detection coils and the second detection coils, and receives echo signals from the powered device via the first detection coils and the second detection coils, and detects the position of the power receiving coil of the powered device placed on a predetermined charging surface based on the detection voltages in the first detection coils and the second detection coils; a power transmission coil moving device that moves one of the plurality of power transmission coils to a position opposite to the power receiving coil detected by the position detection device; and a power supply unit that supplies power to the power transmission coils. The position detection device, when power is already being supplied via one of the power transmission coils, invalidates and excludes from detection the first detection coils and the second detection coils located within a predetermined distance from the mounting position of the power receiving coil to which power is being supplied. [Effects of the Invention]

[0007] According to the wireless power supply device of this disclosure, the location of a newly placed terminal can be reliably detected even when there is a terminal already receiving power. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a plan view of the main part of a wireless power supply device according to the first embodiment. [Figure 2] Figure 2 is a front view of the main part of the wireless power supply device according to the first embodiment. [Figure 3] Figure 3 is a side view of the main part of the wireless power supply device according to the first embodiment. [Figure 4] Figure 4 is an exploded perspective view of a wireless power supply device according to the first embodiment. [Figure 5] Figure 5 is a perspective view of a wireless power supply device according to the first embodiment. [Figure 6] Figure 6 is a block diagram of a wireless power supply device and a power receiving terminal according to the first embodiment. [Figure 7] Figure 7 is an explanatory diagram of the detected voltage waveforms in the first and second search coils. [Figure 8] Figure 8 is a flowchart of the operation process of the first embodiment. [Figure 9] Figure 9 is an explanatory diagram of the settings for the first search coil, which is disabled and not used for position detection. [Figure 10] Figure 10 is a flowchart of the operation process of the second embodiment. [Figure 11] Figure 11 is an operation process flowchart (part 1) of the third embodiment. [Figure 12] Figure 12 is an operation process flowchart (part 2) of the third embodiment. [Figure 13] Figure 13 is an explanatory diagram of an example of threshold voltage setting. [Figure 14] Figure 14 is an explanatory diagram of the range of the X coordinate. [Figure 15] Figure 15 is an explanatory diagram of a specific example of the fourth embodiment. [Modes for carrying out the invention]

[0009] In each of the embodiments described below, the control method of the wireless power supply device 1 of this disclosure will be explained with reference to the drawings. However, each of the embodiments described below is only a part of the various embodiments of this disclosure. Each of the embodiments described below can be modified in various ways depending on the design, etc., as long as the objectives of this disclosure are achieved. Furthermore, each of the embodiments described below may be implemented by combining them as appropriate, including modified versions.

[0010] Furthermore, the figures described in each embodiment below are schematic diagrams, and the ratios of the size and thickness of each component shown in the figures do not necessarily reflect the actual dimensional ratios.

[0011] In addition, the arrows indicating the front-back, left-right, and up-down directions in each drawing are merely for illustrative purposes and do not have a physical entity. Also, the arrows indicating the X-axis and Y-axis in each drawing are merely for illustrative purposes and do not have a physical entity.

[0012] In addition, the front-back, left-right, and up-down directions in the present disclosure are merely examples and are not intended to limit the direction during the use of the wireless power supply device 1.

[0013] Also, the X-axis direction and the Y-axis direction intersect each other. In the present disclosure, it is described that the X-axis direction and the Y-axis direction are perpendicular to each other, the X-axis direction coincides with the left-right direction, and the Y-axis direction coincides with the front-back direction. However, it is not essential that the X-axis direction and the Y-axis direction are perpendicular to each other.

[0014] In addition, the flowcharts shown in the following description are merely examples of the usage method (control method) of the wireless power supply device 1 according to the present disclosure, and the order of the processes may be appropriately changed, and processes may be appropriately added or omitted.

[0015] [1] First Embodiment FIG. 1 is a plan view of the main part of the wireless power supply device according to the first embodiment. FIG. 2 is a front view of the main part of the wireless power supply device according to the first embodiment. FIG. 3 is a side view of the main part of the wireless power supply device according to the first embodiment. FIG. 4 is an exploded perspective view of the wireless power supply device according to the first embodiment. FIG. 5 is a perspective view of the wireless power supply device according to the first embodiment. When the power receiving terminal 9 (see FIG. 5) is placed (arranged) on the power transmission possible area 210 (see FIG. 5) provided on the surface of the wireless power supply device 1, the wireless power supply device 1 transmits power to the power receiving terminal 9. In this case, the power receiving terminal 9 operates, for example, by the power received from the wireless power supply device 1, or charges a battery by the power received from the wireless power supply device 1.

[0016] As shown in Figure 1, the wireless power supply device 1 of this embodiment comprises a power transmission unit 8, a position detection device 3 (see Figure 4), a movement system M1, and a housing 2. The power transmission unit 8 includes a power transmission coil 81. The power transmission coil 81 transmits power to a power receiving coil 91 located in the power receiving terminal 9. The position detection device 3 detects the position of the power receiving coil 91. Based on the position of the receiving coil 91 detected by the position detection device 3, the moving system M1 moves the transmitting coil 81 to a position opposite the receiving coil 91. In the above configuration, the housing 2 houses the power transmission unit 8, the mobile system M1, and the position detection device 3. The moving system M1 includes an X-axis rail 4 along the X-axis direction, a Y-axis rail 6 along the Y-axis direction intersecting the X-axis direction, an X-axis drive unit 5 that moves the Y-axis rail 6 along the X-axis rail 4, and a Y-axis drive unit 7 that moves the power transmission unit 8, which is movably connected to the Y-axis rail 6, along the Y-axis rail 6. The Y-axis rail 6 is movably connected to the X-axis rail 4. The X-axis drive unit 5 is held by the Y-axis rail 6. The Y-axis drive unit 7 is held by the power transmission unit 8.

[0017] Furthermore, as shown in Figure 1, the wireless power supply device 1 of this embodiment includes two power transmission units 8, two Y-axis rails 6, two X-axis drive units 5, and two Y-axis drive units 7.

[0018] Hereafter, the two power transmission units 8 will also be referred to as the first power transmission unit 8A and the second power transmission unit 8B, respectively. Furthermore, the power transmission coil 81 included in the first power transmission unit 8A will also be referred to as the first power transmission coil 81A, and the power transmission coil 81 included in the second power transmission unit 8B will also be referred to as the second power transmission coil 81B.

[0019] The two Y-axis rails 6 are also referred to as the first Y-axis rail 6A and the second Y-axis rail 6B, respectively. The two X-axis drive units 5 are also referred to as the first X-axis drive unit 5A and the second X-axis drive unit 5B, respectively. The two Y-axis drive units 7 are also referred to as the first Y-axis drive unit 7A and the second Y-axis drive unit 7B, respectively.

[0020] The second power transmission coil 81B of the second power transmission unit 8B transmits power to the power receiving coil 91 of the power receiving terminal 9.

[0021] The second Y-axis rail 6B is movably connected to the X-axis rail 4. The second Y-axis rail 6B is aligned along the Y-axis direction.

[0022] The second X-axis drive unit 5B moves the second Y-axis rail 6B along the X-axis rail 4, independently of the movement of the first Y-axis rail 6A. The second X-axis drive unit 5B is held by the second Y-axis rail 6B.

[0023] The second Y-axis drive unit 7B is connected to the second Y-axis rail 6B so as to be movable, and the second power transmission unit 8B is connected to it. It moves along the second Y-axis rail 6B. The second Y-axis drive unit 7B is held by the second power transmission unit 8B.

[0024] In this way, since the first Y-axis rail 6A and the second Y-axis rail 6B are movably connected to a common X-axis rail 4, the number of X-axis rails 4 can be reduced, making the moving system M1 more compact.

[0025] The mobile system M1 of the wireless power supply device 1 is controlled by a control method performed by a computer system. The mobile system M1 moves the first power transmission unit 8A, which includes the first power transmission coil 81A, and the second power transmission unit 8B, which includes the second power transmission coil 81B. The first power transmission coil 81A transmits power to the power receiving coil 91 of the power receiving terminal 9. The second power transmission coil 81B transmits power to the power receiving coil 91. The control method includes a position detection process and a movement control process. In the position detection process, the position of the power receiving coil 91 is detected. In the movement control process, based on the position of the power receiving coil 91 detected in the position detection process, the mobile system M1 is controlled to move at least one of the first power transmission coil 81A and the second power transmission coil 81B.

[0026] If the position detection process detects the position of one power receiving coil 91, the movement control process moves one of the first power transmitting coil 81A and the second power transmitting coil 81B to a position opposite the power receiving coil 91. The first power transmitting unit 8A is movably connected to the first Y-axis rail 6A along the Y-axis direction. The second power transmitting unit 8B is movably connected to the second Y-axis rail 6B along the Y-axis direction. The first Y-axis rail 6A and the second Y-axis rail 6B are movably connected to the X-axis rail 4 along the X-axis direction which intersects with the Y-axis direction. The movement control process includes a first process of moving the first Y-axis rail 6A along the X-axis rail 4, a second process of moving the first power transmission unit 8A along the first Y-axis rail 6A, a third process of moving the second Y-axis rail 6B along the X-axis rail 4 independently of the movement of the first Y-axis rail 6A, and a fourth process of moving the second power transmission unit 8B along the second Y-axis rail 6B.

[0027] With the above configuration, the first Y-axis rail 6A and the second Y-axis rail 6B are movably connected to a common X-axis rail 4, and the first to fourth processes allow the first power transmission unit 8A and the second power transmission unit 8B to be moved in the X-axis and Y-axis directions. Therefore, convenience can be improved compared to the case where only the first power transmission unit 8A is moved.

[0028] Furthermore, compared to a case where the first Y-axis rail 6A is movably connected to the first X-axis rail, while the second Y-axis rail 6B is not movably connected to the first X-axis rail but is movably connected to the second X-axis rail, the number of X-axis rails 4 can be reduced, making the moving system M1 more compact.

[0029] The wireless power supply device 1 of this embodiment will be described in more detail below. As shown in Figures 1 and 4, the wireless power supply device 1 comprises a first power transmission unit 8A, a second power transmission unit 8B, a position detection device 3, a movement system M1, a housing 2, and a controller 14.

[0030] The moving system M1 includes two X-axis rails 4 (4A and 4B), two X-axis drive units 5, two Y-axis rails 6, two Y-axis drive units 7, two cables 12, and two driven units 13. As shown in Figure 1, it is preferable that the moving system M1 further includes two first support bases 11A and two second support bases 11B. By including these support bases, the height of the X-axis rails 4 can be adjusted.

[0031] This allows for the commonization of the mobile system M1 across multiple wireless power supply devices with different power transmission area ranges 210 or different housing shapes 2, thereby reducing costs.

[0032] As shown in Figure 1, the wireless power supply device 1 includes two Y-axis rail units U1. Each of the two Y-axis rail units U1 is movably connected to the two X-axis rails 4. Each of the two Y-axis rail units U1 includes the aforementioned power transmission unit 8, X-axis drive unit 5, Y-axis rail 6, Y-axis drive unit 7, cable 12, and driven unit 13.

[0033] Although Figure 1 shows two Y-axis rail units U1, there may be one or three or more. Multiple Y-axis rail units U1 provided by a single wireless power supply device 1 may all have the same structure. Therefore, there is an effect of reducing the manufacturing cost of multiple Y-axis rail units U1.

[0034] Furthermore, this design allows for the use of a common Y-axis rail unit U1 in both wireless power supply units 1 with a relatively long X-axis rail 4 and wireless power supply units 1 with a relatively short X-axis rail 4.

[0035] Figure 6 is a block diagram of a wireless power supply device and a power receiving terminal according to the first embodiment. As shown in Figure 6, the wireless power supply device 1 further comprises multiple (two in Figure 6) power transmission circuits 83 and a communication circuit 84. In Figure 6, the double lines connecting each part represent power lines, and the single lines connecting each part represent communication lines.

[0036] The housing 2 has a cover 21 and a base 22, as shown in Figures 4 and 5. The cover 21 has a rectangular parallelepiped shape and has an opening on its lower surface. The cover 21 also has a display device 211. The display device 211 displays a predetermined information, as will be described later. The display device 211 includes, for example, a display. The area where the display device 211 is provided includes at least a portion of the power transmission area 210. When a power receiving terminal 9 is placed in the power transmission area 210, one of the two power transmission coils 81 moves to a position facing the power receiving coil 91 of the power receiving terminal 9 and transmits power to the power receiving coil 91.

[0037] The base 22 has a rectangular parallelepiped shape and an opening 220 on its upper surface. The opening 220 in the base 22 faces the opening on the lower surface of the cover 21. The cover 21 is attached to the base 22 and covers the opening 220 in the base 22. Two power transmission units 8, a position detection device 3, and a movement system M1 are housed in the space between the cover 21 and the base 22. More specifically, as shown in Figure 4, the two power transmission units 8 and the movement system M1 are positioned below the position detection device 3.

[0038] The controller 14 includes a computer system having one or more processors and memory. At least some of the functions of the controller 14 are realized by the execution of a program stored in the memory of the computer system by the processor of the computer system. The program may be stored in memory, provided via a telecommunication line such as the Internet, or provided on a non-temporary recording medium (such as a memory card) that is readable by the computer system.

[0039] As shown in Figure 1, the controller 14 has an identification unit 141 and a movement control unit 142. Note that these merely represent the functions realized by the controller 14 and do not necessarily represent the actual physical configuration.

[0040] The identification unit 141 determines the position of the power receiving coil 91 based on the detection result of the position detection device 3. The movement control unit 142 controls the movement of the two power transmission units 8 by controlling the operation of the two X-axis drive units 5 and the two Y-axis drive units 7.

[0041] The controller 14 may be housed in the housing 2 as shown in Figure 1. Alternatively, the controller 14 may be located outside the housing 2. Furthermore, the controller 14 may be a component of a device separate from the wireless power supply device 1.

[0042] The two power transmission circuits 83 correspond one-to-one with the two power transmission coils 81. Each power transmission circuit 83 supplies power to its corresponding power transmission coil 81.

[0043] Each power transmission circuit 83 includes, for example, a full-bridge inverter or an oscillator circuit such as a Class D or Class E oscillator. The power transmission circuit 83 is connected to a DC power source and converts the DC power input from the DC power source into AC power for output. This AC power is supplied to the power transmission coil 81 via the cable 12 and transmitted to the power receiving terminal 9 via the magnetic flux generated by the power transmission coil 81 based on the principle of electromagnetic induction.

[0044] The communication circuit 84 communicates wirelessly with the communication circuit 94 of the power receiving terminal 9 and receives information from the power receiving terminal 9, for example, which is necessary for transmitting power from the power transmitting coil 81 to the power receiving coil 91. This information is transmitted to the controller 14 and used to control the transmission frequency and the magnitude of the transmitted power sent out by the power transmitting coil 81.

[0045] The controller 14, the two power transmission circuits 83, and the communication circuit 84 may be integrated into a single package, or they may be distributed across multiple packages.

[0046] As shown in Figure 4, the position detection device 3 includes a first detection unit 31 and a second detection unit 32. The first detection unit 31 includes a plurality of first search coils 310. The second detection unit 32 includes a plurality of second search coils 320. Each of the multiple first search coils 310 extends in the front-to-back direction, which is the first direction, in the example shown in Figure 4, and the first search coils 310 are arranged parallel to each other. Similarly, in the example shown in Figure 4, each of the multiple second search coils 320 extends in the second direction, which is the left-right direction, and the second search coils 320 are arranged parallel to each other.

[0047] The first detection unit 31 and the second detection unit 32 are each plate-shaped. The first detection unit 31 overlaps the second detection unit 32 in the vertical direction.

[0048] The position detection device 3 includes, for example, a printed circuit board, which is, for example, a double-sided board or a multilayer board. The printed circuit board includes a first layer (for example, a layer provided on the top surface) and a second layer (for example, a layer provided on the bottom surface, or a layer between the top and bottom surfaces) that overlaps the first layer in the vertical direction. A plurality of first search coils 310 are arranged on the first layer of the printed circuit board, and a plurality of second search coils 320 are arranged on the second layer of the printed circuit board.

[0049] Each of the multiple first search coils 310 has a rectangular shape when viewed from above. The longitudinal direction of each of the multiple first search coils 310 is aligned with the front-to-back direction, which is the first direction. The multiple first search coils 310 are arranged parallel to each other in the left-to-right direction.

[0050] Each of the multiple second search coils 320 has a rectangular shape when viewed from above. The longitudinal direction of each of the multiple second search coils 320 is aligned with the left-right direction, which is the second direction. The multiple second search coils 320 are arranged parallel to each other in the front-back direction.

[0051] Here, we will explain the general operation of the position detection device 3. Figure 7 is an explanatory diagram of the detected voltage waveforms in the first and second search coils. In this case, it is assumed that only one power receiving terminal 9 is located in the power transmission area 210, and that no charging is being performed. At a predetermined position detection timing, the identification unit 141 of the controller 14 supplies a predetermined position detection pulse signal P1 (for example, a 1 MHz rectangular pulse) as shown in Figure 7(A) to a plurality of first search coils 310 and a plurality of second search coils 320.

[0052] When the power receiving terminal 9 is placed in the terminal mounting area on the upper surface of the cover 21, the power receiving coil 91 of the power receiving terminal 9 is excited by the position detection pulse signal P1 and transmits the echo signal E1 shown in Figure 7(B).

[0053] As a result, among the multiple first search coils 310, the first search coil 310 in the vicinity of the power receiving coil 91 receives the echo signal E1 from the power receiving coil 91 and outputs it to the identification unit 141. Similarly, among the multiple second search coils 320, the second search coil 320 in the vicinity of the receiving coil 91 receives the echo signal E1 from the receiving coil 91 and outputs it to the identification unit 141.

[0054] The identification unit 141 determines the X coordinate of the receiving coil 91 based on the position information of each of the multiple first search coils 310 and the voltage level of the echo signal E1. For example, the identification unit 141 determines that the X-coordinate of the first search coil 310 whose echo signal E1 level is above a threshold voltage and is the highest among the multiple first search coils 310 is the X-coordinate of the receiving coil 91.

[0055] In this case, for simplicity, the center coordinates of the first search coil 310 in the X direction (left-right direction) can be used as the X coordinate of the receiving coil 91. However, to more accurately determine the X coordinate of the receiving coil 91, interpolation may be performed based on the intensity of the echo signals E1 of multiple adjacent first search coils 310 to determine the X coordinate of the receiving coil 91.

[0056] Incidentally, as shown in Figure 7(C), if a power receiving terminal 9 is already in operation, the detection voltage may increase due to the noise signal N1 caused by the power supply, exceeding the threshold voltage th, which could lead to a false detection that the power receiving coil 91 is in position. Therefore, in the first embodiment, the first search coil 310 and the second search coil 320 are disabled in order to prevent them from being used for position detection when they are in this state.

[0057] Next, the operation of the position detection device 3 will be explained. In the initial state, it is assumed that there are no power receiving terminals 9 having a power receiving coil 91 to be detected, or that only one such terminal is installed.

[0058] The position detection device 3, under the control of the controller 14, outputs a position detection pulse signal P1 shown in Figure 7(A) to the first search coil 310 at predetermined terminal detection timings, and compares the output voltage of the first search coil 310 after output with a predetermined threshold voltage th.

[0059] Furthermore, after comparing the output voltages of the first search coil 310, the position detection device 3 outputs the position detection pulse signal P1 shown in Figure 7(A) to the second search coil 320, and compares the output voltage of the second search coil 320 after output with a predetermined threshold voltage th.

[0060] In this case, if the power receiving terminal 9 is not located on the upper surface of the position detection device 3, no echo signal E1 will be output from the power receiving coil 91 of the power receiving terminal 9, and therefore the output voltages of the multiple first search coils 310 and the multiple second search coils 320 will not exceed a predetermined threshold voltage th.

[0061] In contrast, if the power receiving terminal 9 is located on the upper surface of the position detection device 3, an echo signal E1 will be output from the power receiving coil 91 of the power receiving terminal 9. Therefore, the position detection device 3 will identify the first search coil 310 and the second search coil 320 from among the plurality of first search coils 310 and plurality of second search coils 320 whose output voltage exceeds a predetermined threshold voltage th.

[0062] The position detection device 3 then identifies the first search coil 310 and the second search coil 320, which have detected higher voltages, and determines that the receiving coil 91 of the receiving terminal 9 is located at the intersection of the identified first search coil 310 and second search coil 320 when the position detection device 3 is viewed from above (corresponding to the receiving terminal position), and acquires its position.

[0063] Alternatively, instead of the intersection of the first search coil 310 and the second search coil 320 described above, the position of the power receiving coil 91 of the power receiving terminal 9 may be identified and acquired by the following method.

[0064] Specifically, for the first search coil 310 whose output voltage exceeds a predetermined threshold voltage th, a graph is assumed in which the detected voltages are arranged in the order of the first search coil 310's position. The detected voltages are interpolated, and the first position, which is the highest voltage position on the graph, is calculated.

[0065] Similarly, for the second search coil 320 whose output voltage exceeds a predetermined threshold voltage th, a graph is assumed in which the detected voltages are arranged in the order of the second search coil 320's position. The detected voltages are interpolated, and the second position, which is the highest voltage position on the graph, is calculated. Then, the intersection point of a straight line passing through the first position and extending in the first direction, and a straight line passing through the second position and extending in the second direction, is identified and acquired as the position of the power receiving coil 91 of the power receiving terminal 9.

[0066] Next, the operation of the wireless power supply device of the first embodiment will be described. Figure 8 is a flowchart of the operation process of the first embodiment. When the wireless power supply device reaches a predetermined timing for detecting the presence or absence of a power receiving terminal, the position detection device 3 performs a detection process to determine whether or not a power receiving terminal 9 is present (step S11).

[0067] Then, in the detection process of step S11, it is determined whether the detection level of the voltage of either the first search coil 310 or the second search coil 320 is equal to or greater than a predetermined threshold voltage th (step S12).

[0068] In the determination in step S12, if the detected voltage levels of all first search coils 310 and second search coils 320 are below a predetermined threshold voltage th (step S12; No), the process proceeds to step S11, and the system enters a waiting state until the next power receiving terminal presence detection timing, at which point the above-described process is performed.

[0069] In the determination in step S12, if the detected voltage level of either the first search coil 310 or the second search coil 320 is equal to or greater than a predetermined threshold voltage th (step S12; Yes), the position detection device 3 performs the position detection process described above and obtains the position information of the first power receiving terminal 9 (step S13).

[0070] Next, the controller 14 moves the power transmission coil 81 via the mobile system M1 to a position corresponding to the location information of the first power receiving terminal 9, starts supplying power (charging) to the first power receiving terminal 9, and stores the location information of the first power receiving terminal 9 in a memory (not shown) (step S14).

[0071] In this state, since there already exists a power receiving terminal 9 that is already being supplied with power (charged), it is necessary to avoid affecting the position detection of other power receiving terminals 9. For this reason, so that the position detection process in the position detection device 3 is not affected by the magnetic flux (magnetic field) generated by power supply, among the first search coil 310 and the second search coil 320 in the position detection device 3, the first search coil 310 and the second search coil 320 that are not used for position detection are set to be invalidated (step S15).

[0072] Here, the setting of the first search coil 310 and the second search coil 320 that are not used for position detection will be described taking the first search coil 310 as an example. FIG. 9 is an explanatory diagram of the setting of the first search coil that is invalidated and not used for position detection. In the following description, as an example, it is assumed that there are cases where the power supply power is 5 W and the power supply power is 12 W. As shown in FIG. 9, assuming that the X coordinate of the power receiving coil 91 of the power receiving terminal 9 during power reception is x, the region where the first search coil 310 is affected when 5 W of power is supplied is when at least a part of the first search coil 310 is located within the X coordinate range AR_L = x + a to x - a.

[0073] Similarly, assuming that the X coordinate of the power receiving coil 91 of the power receiving terminal 9 during power reception is x, the region where the first search coil 310 is affected when 12 W of power is supplied is when at least a part of the first search coil 310 is located within the X coordinate range AR_H = x + b to x - b (where a < b).

[0074] More specifically, in the case of the example shown in FIG. 9, the first search coil 310(n) located in the nth row is not entirely located within either the X coordinate range AR_L = x + a to x - a or the X coordinate range AR_H = x + b to x - b. Therefore, regardless of whether it is 5 W power supply or 12 W power supply, the detection voltage of the first search coil 310(n) will not be affected. Therefore, in the position detection device 3, the first search coil 310(n) is recognized as a search coil effective for position detection. On the one hand, the first search coil 310(n+1) located in the (n+1)-th column is not entirely located within the X-coordinate range AR_L = x + a to x - a, but a part of it is located within the X-coordinate range AR_H = x + b to x - b. Therefore, in the case of 5W power supply, it will not affect the detected voltage of the first search coil 310(n), but in the case of 12W power supply, it will be affected. Therefore, in the position detection device 3, unless the power supply power is determined, there is a possibility of false detection. Thus, the first search coil 310(n+1) will be set as a search coil with ineffective position detection.

[0075] Therefore, in the first embodiment, since the transmission power (in the case of the above example, either 5W power supply or 12W power supply) is not judged, in order to more reliably prevent false detection, when 12W power supply is performed, the X-coordinate range = x + b to x - b (where a < b), which is the area that affects the first search coil 310, is used to set the ineffective search coil.

[0076] As described above, when at least a part of the first search coil 310 is located in the area affected by the power supply, even when the echo signal E1 does not exist, as shown in Fig. 7(C), the detected voltage becomes high due to the noise signal N1 caused by the power supply to the power receiving terminal 9 that has already been executed, exceeding the threshold voltage th, and there is a high possibility of false detection that the power receiving coil 91 is located.

[0077] Therefore, since the position detection device 3 stores the position of the first search coil 310 in advance, it is set not to use the first search coil 310 located within the predetermined X-coordinate range for position detection.

[0078] In this case, not using for position detection can be considered in the following two modes. In the first aspect, the position detection device 3 outputs a position detection pulse signal P1 to a first search coil 310 set not to be used for position detection, and does not detect an echo signal E1. As a result, regardless of the presence or absence of the generation of the echo signal E1 and the detection voltage of the first search coil 310, it is not determined whether the detection voltage of the first search coil 310 is equal to or higher than a threshold voltage th, so it is not used for position detection.

[0079] In the second aspect, the position detection device 3 does not output a position detection pulse signal P1 to the first search coil 310 set not to be used for position detection, and does not detect an echo signal E1. As a result, the echo signal E1 does not occur either, and regardless of the detection voltage of the first search coil 310, it is not determined whether the detection voltage of the first search coil 310 is equal to or higher than a threshold voltage th, so the first search coil 310 is not used for position detection.

[0080] Also, for the second search coil 320, assuming that the Y coordinate of the power receiving coil 91 of the power receiving terminal 9 during power reception is y, when 5W power supply is performed, the region where the second search coil 320 is affected is when a part of the second search coil 320 is located within the Y coordinate range of y + a to y - a.

[0081] Similarly, assuming that the Y coordinate of the power receiving coil 91 of the power receiving terminal 9 during power reception is y, when 12W power supply is performed, the region where the second search coil 320 is affected is when a part of the second search coil 320 is located within the Y coordinate range of y + b to y - b (where a < b).

[0082] In the first embodiment, as described above, the transmission power (in the case of the above example, either 5W power supply or 12W power supply) is not determined. Therefore, in order to prevent false detection, when 12W power supply is performed, the setting is made using the Y coordinate range of y + b to y - b (where a < b), which is the region where the second search coil 320 is affected.

[0083] Once the settings for the first search coil 310 and the second search coil 320, which are not used for position detection, are completed, the position detection device 3 removes the first search coil 310 and the second search coil 320 that have been disabled and are not used for position detection, thereby limiting the number of valid first search coils 310 and the second search coil 320 used for position detection, and performs the detection of the presence or absence of a new power receiving terminal 9 (step S16).

[0084] Then, in the detection process of step S11, it is determined whether the detection level of the voltage of either the first search coil 310 or the second search coil 320 is equal to or greater than a predetermined threshold voltage th (step S17).

[0085] In the determination in step S17, if the detected voltage levels of all first search coils 310 and second search coils 320 are below a predetermined threshold voltage th (step S17; No), the process proceeds to step S16, and the system enters a waiting state until the next power receiving terminal presence detection timing, at which point the above-described process is performed.

[0086] In the determination in step S17, if the detected voltage level of either the first search coil 310 or the second search coil 320 is equal to or greater than a predetermined threshold voltage th (step S17; Yes), the position detection device 3 performs the position detection process described above and obtains the position information of the second power receiving terminal 9 (step S18).

[0087] Next, the controller 14 moves the power transmission coil 81, which is not currently charging, to a position corresponding to the location information of the second power receiving terminal 9 via the mobile system M1, starts supplying power (charging) to the second power receiving terminal 9, and stores the location information of the first power receiving terminal 9 in a memory (not shown) (step S19).

[0088] As described above, according to this first embodiment, even when there is a powered device that is already receiving power, the influence of power supply on the position detection device 3 can be suppressed, and the position of a new powered device can be correctly detected.

[0089] [2] Second embodiment The difference between the second embodiment and the first embodiment is that the second embodiment acquires the maximum power corresponding to the transmission power mode for the powered terminal 9, which is the powered device, and sets a search coil that is not used for position detection based on the maximum power. Since the device configuration of the second embodiment is the same as that of the first embodiment, the operation of the wireless power supply device of the second embodiment will be described below.

[0090] Figure 10 is a flowchart of the operation process of the second embodiment. In Figure 10, parts identical to those in Figure 8 shall be denoted by the same reference numerals. When the wireless power supply device reaches a predetermined timing for detecting the presence or absence of a power receiving terminal, the position detection device 3 performs a detection process to determine whether or not a power receiving terminal 9 is present (step S11).

[0091] Then, in the detection process of step S11, it is determined whether the detection level of the voltage of either the first search coil 310 or the second search coil 320 is equal to or greater than a predetermined threshold voltage th (step S12).

[0092] In the determination in step S12, if the detected voltage levels of all first search coils 310 and second search coils 320 are below a predetermined threshold voltage th (step S12; No), the process proceeds to step S11, and the system enters a waiting state until the next power receiving terminal presence detection timing, at which point the above-described process is performed.

[0093] In the determination in step S12, if the detected voltage level of either the first search coil 310 or the second search coil 320 is equal to or greater than a predetermined threshold voltage th, the position detection device 3 performs the position detection process described above and obtains the position information of the first power receiving terminal 9 (step S13).

[0094] Subsequently, the controller 14 moves the power transmission coil 81 to a position corresponding to the position information of the first power receiving terminal 9 via the movement system M1, starts power supply (charging) to the first power receiving terminal 9, and stores the position information of the first power receiving terminal 9 in a memory (not shown) (step S14).

[0095] Next, the position detection device 3 acquires from the controller 14 the maximum transmission power corresponding to the transmission power mode of the first power receiving terminal 9 (step S21). Then, the position detection device 3 determines whether or not the maximum transmission power corresponding to the transmission power mode of the first power receiving terminal 9 acquired is 12 W or more (step S22).

[0096] In the determination of step S22, when the maximum transmission power corresponding to the transmission power mode of the first power receiving terminal 9 is 12 W or more (step S22; Yes), since there already exists a power receiving terminal 9 for which power supply (charging) is already being performed, it is necessary to avoid affecting the position detection of other power receiving terminals 9.

[0097] Therefore, when the maximum transmission power is 12 W or more, the position detection device 3 sets the first search coil 310 and the second search coil 320 that are not used for position detection (step S23).

[0098] More specifically, assuming that the X coordinate of the power receiving coil 91 of the power receiving terminal 9 during power reception is x, when power supply of 12 W is being performed, the region where the first search coil 310 is affected is the first search coil 310 at least partially located within the X coordinate range of x + b to x - b (where a < b), and thus the first search coil 310 corresponding to this is set as the first search coil 310 not used for position detection.

[0099] Similarly, assuming that the Y coordinate of the power receiving coil 91 of the power receiving terminal 9 during power reception is y, when 12 W power supply is being performed, the region that affects the second search coil 320 is the second search coil 320 where at least a part is located in the Y coordinate range of y + b to y - b (where a < b). Therefore, the second search coil 320 corresponding to this is set as an invalid second search coil 320 that is not used for position detection.

[0100] In the determination of step S22, even when the maximum transmission power corresponding to the transmission power mode of the first power receiving terminal 9 is less than 12 W (step S22; No), since there already exists a power receiving terminal 9 for which power supply (charging) is already being performed, it is necessary to avoid affecting the position detection of other power receiving terminals 9.

[0101] For this reason, the position detection device 3 sets the first search coil 310 and the second search coil 320 that are not used for position detection when the maximum transmission power is less than 12 W (step S24).

[0102] More specifically, assuming that the X coordinate of the power receiving coil 91 of the power receiving terminal 9 during power reception is x, when 12 W power supply is being performed, the region that affects the first search coil 310 is the first search coil 310 where at least a part is located in the X coordinate range of x + a to x - a (where a < b). Therefore, the first search coil 310 corresponding to this is set as the first search coil 310 that is not used for position detection.

[0103] Similarly, assuming that the Y coordinate of the power receiving coil 91 of the power receiving terminal 9 during power reception is y, when 12 W power supply is being performed, the region that affects the second search coil 320 is the second search coil 320 where at least a part is located in the Y coordinate range of y + a to y - a (where a < b). Therefore, the second search coil 320 corresponding to this is set as an invalid second search coil 320 that is not used for position detection.

[0104] Once the settings for the first search coil 310 and the second search coil 320, which are not used for position detection, are completed, the position detection device 3 removes the first search coil 310 and the second search coil 320 that have been disabled and are not used for position detection, thereby limiting the number of valid first search coils 310 and the second search coil 320 used for position detection, and performs the detection of the presence or absence of a new power receiving terminal 9 (step S16).

[0105] Then, in the detection process of step S11, it is determined whether the detection level of the voltage of either the first search coil 310 or the second search coil 320 is equal to or greater than a predetermined threshold voltage th (step S17).

[0106] In the determination in step S17, if the detected voltage levels of all first search coils 310 and second search coils 320 are below a predetermined threshold voltage th (step S17; No), the process proceeds to step S16, and the system enters a waiting state until the next power receiving terminal presence detection timing, at which point the above-described process is performed.

[0107] In the determination in step S17, if the detected voltage level of either the first search coil 310 or the second search coil 320 is equal to or greater than a predetermined threshold voltage th (step S17; Yes), the position detection device 3 performs the position detection process described above and obtains the position information of the second power receiving terminal 9 (step S18).

[0108] Next, the controller 14 moves the power transmission coil 81, which is not currently charging, to a position corresponding to the location information of the second power receiving terminal 9 via the mobile system M1, starts supplying power (charging) to the second power receiving terminal 9, and stores the location information of the first power receiving terminal 9 in a memory (not shown) (step S19).

[0109] As described above, according to this second embodiment, even when there is a powered device already receiving power, the impact of power supply on the position detection device 3 can be suppressed by minimizing the first search coil 310 and the second search coil 320 that are not used for position detection based on the maximum power supply, thereby securing more positions where the position of a new powered device can be correctly detected. Alternatively, the number of power transmission coils can be increased to supply power to more receiving terminals in the same area.

[0110] [3] Third embodiment The third embodiment differs from the first and second embodiments described above in that the threshold voltage used for position detection is not constant, but is changed and set. Since the device configuration of the second embodiment is the same as that of the first embodiment, the operation of the wireless power supply device of the second embodiment will be described below.

[0111] Figure 11 is an operation process flowchart (part 1) of the third embodiment. Figure 12 is an operation process flowchart (part 2) of the third embodiment. In Figures 11 and 12, the same reference numerals are used for parts that are the same as those in the second embodiment of Figure 10. Furthermore, in the following explanation, for the sake of ease of understanding, we will mainly describe the processing applied to the first search coil 310, but the same processing will be applied to the second search coil 320. When the wireless power supply device reaches a predetermined timing for detecting the presence or absence of a power receiving terminal, the position detection device 3 performs a detection process to determine whether or not a power receiving terminal 9 is present (step S11).

[0112] Then, in the detection process of step S11, it is determined whether the detection level of the voltage of either the first search coil 310 or the second search coil 320 is equal to or greater than a predetermined threshold voltage th (step S12).

[0113] In the determination in step S12, if the detected voltage levels of all first search coils 310 and second search coils 320 are below a predetermined threshold voltage th (step S12; No), the process proceeds to step S11, and the system enters a waiting state until the next power receiving terminal presence detection timing, at which point the above-described process is performed.

[0114] In the determination in step S12, if the detected voltage level of either the first search coil 310 or the second search coil 320 is equal to or greater than a predetermined threshold voltage th, the position detection device 3 performs the position detection process described above and obtains the position information of the first power receiving terminal 9 (step S13).

[0115] Next, the controller 14 moves the power transmission coil 81 via the mobile system M1 to a position corresponding to the location information of the first power receiving terminal 9, starts supplying power (charging) to the first power receiving terminal 9, and stores the location information of the first power receiving terminal 9 in a memory (not shown) (step S14). Next, the position detection device 3 obtains the maximum transmission power corresponding to the transmission power mode of the first power receiving terminal 9 from the controller 14 (step S21). Then, the position detection device 3 determines whether the maximum transmission power corresponding to the transmission power mode of the first power receiving terminal 9 is 12W or more (step S22). For ease of understanding, the following explanation will primarily use the first search coil 310 as an example.

[0116] Figure 13 is an explanatory diagram of an example of threshold voltage setting. In the following explanation, three threshold voltages, thA to thC, will be used as threshold voltages corresponding to the detected voltage.

[0117] For example, the threshold voltage thA is set when it is assumed that the influence of power supply to other powered terminals 9 has the smallest possible impact on the location detection of a new powered terminal. For example, the threshold voltage thA is set to 0.5[V].

[0118] The threshold voltage thB is a threshold voltage set when it is assumed that the influence of power supply to other power receiving terminals 9 on the position detection of the new power receiving terminal is relatively large. For example, the threshold voltage thB is set to 3 [V].

[0119] The threshold voltage thC is a threshold voltage set when it is assumed that the influence of power supply to other power receiving terminals 9 on the position detection of the new power receiving terminal is large. For example, the threshold voltage thB is set to 5 [V].

[0120] FIG. 14 is an explanatory diagram of the range of the X coordinate. In the determination of step S22, when the maximum transmission power corresponding to the transmission power mode of the first power receiving terminal 9 is 12 W or more (step S22; Yes), for any one of the first search coils 310 (in the example of FIG. 14, for the first search coil 310(n), assuming that the X coordinate of the power receiving coil 91c of the power receiving terminal 9 during power reception is x, it is determined whether at least a part of each first search coil 310 is located within the X coordinate range AR_M = x + b to x - b (where a < b)) (step S41).

[0121] In the determination of step S41, when at least a part of the first search coil 310 is located within the X coordinate range AR_M = x + b to x - b (where a < b) (step S41; Yes), the threshold voltage for presence / absence detection is set to the threshold voltage thC (5 [V] in the above example) that is least affected by the power supply to the power receiving terminal 9 among the predetermined threshold voltages (step S42), and the process proceeds to step S50.

[0122] In the determination of step S41, when the first search coil 310 is not located within the X coordinate range AR_M = x + b to x - b (where a < b) (step S41; No), it is determined whether at least a part of the first search coil 310 is located within the X coordinate range AR_H = x + c to x - c (where b < c) (step S43).

[0123] In the determination of step S43, if at least a part of the first search coil 310 is located within the X - coordinate range AR_H = x + c to x - c (where a < b), (step S43; Yes), the threshold voltage for presence / absence detection is set to a threshold voltage thB (for example, 3 [V]) that is slightly more susceptible to the power supply influence on the power - receiving terminal 9 than the threshold voltage thC (for example, 5 [V]) which is least susceptible to the power supply influence on the power - receiving terminal 9 among the predetermined threshold voltages thA to thC (step S44), and the process proceeds to step S50.

[0124] In the determination of step S43, if the first search coil 310 is not located within the X - coordinate range AR_H = x + c to x - c b (where a < b), (step S43; No), the threshold voltage for presence / absence detection is set to the threshold voltage thA (for example, 0.5 [V]) that is most susceptible to the power supply influence on the power - receiving terminal 9 among the predetermined threshold voltages thA to thC (step S49), and the process proceeds to step S50.

[0125] On the other hand, in the determination of step S22, if the maximum transmission power corresponding to the transmission power mode of the first power - receiving terminal 9 is less than 12 W, (step S22; No), it is determined whether at least a part of the first search coil 310 is located within the X - coordinate range = x + a to x - a (where a < b < c) (step S45).

[0126] In the determination of step S45, if at least a part of the first search coil 310 is located within the X - coordinate range AR_L = x + a to x - a (where a < b < c), (step S45; Yes), the threshold voltage for presence / absence detection is set to the threshold voltage thC (for example, 5 [V]) that is least susceptible to the power supply influence on the first search coil 310 among the predetermined threshold voltages thA to thC (step S46), and the process proceeds to step S50.

[0127] In the determination of step S45, if the first search coil 310 is not located within the X coordinate range AR_L = x + a to x - a (where a < b < c) (step S45; No), it is determined whether at least a part of the first search coil 310 is located within the X coordinate range = x + b to x - b (where a < b < c) (step S47).

[0128] In the determination of step S47, if at least a part of the first search coil 310 is located within the X coordinate range AR_L = x + a to x - a (where a < b < c) (step S47; Yes), the threshold voltage for presence / absence detection is set to a threshold voltage thB (in the above example, 3 [V]) that is slightly more likely to be affected by power supply to the power receiving terminal 9 than the threshold voltage thC (for example, 5 [V]) which is the least likely to be affected by power supply to the power receiving terminal 9 among the predetermined threshold voltages thA to thC (step S48), and the process proceeds to step S50.

[0129] In the determination of step S47, if the first search coil 310 is not located within the X coordinate range AR_L = x + a to x - a (where a < b < c) (step S47; No), the threshold voltage for presence / absence detection is set to the threshold voltage thA (in the above example, 0.5 [V]) that is most likely to be affected by power supply to the power receiving terminal 9 among the predetermined threshold voltages thA to thC (step S49), and the presence / absence of the receiving terminal is detected (step S50).

[0130] Then, it is determined whether the detected level of the voltage of the first search coil 310 is equal to or higher than the set predetermined threshold voltage (threshold voltage thA) (step S51).

[0131] In the determination of step S51, if the detected level of the first search coil 310 is equal to or higher than the set predetermined threshold voltage thA (step S51; Yes), as information for specifying the first search coil 310, the position information and detected voltage information of the search coil whose detected voltage exceeds the set threshold voltage thA are acquired (step S52), and the process proceeds to step S53.

[0132] In the determination in step S51, if the detection level of the first search coil 310 is less than a predetermined threshold voltage thA (step S51; No), it is determined whether or not information for all search coils has been acquired (step S53).

[0133] In the determination in step S53, if information on all search coils has not been obtained (step S53; No), select the search coils for which information has not yet been obtained (step S54), proceed back to step S41, and repeat the process described above.

[0134] In the determination in step S53, if information on all search coils has been acquired (step S53; Yes), the position detection device 3 performs the position detection process described above based on the acquired search coil information (position information and detection voltage information of search coils whose detection voltage exceeds the set threshold voltage) and acquires the position information of the second power receiving terminal 9 (step S18).

[0135] Next, the controller 14 moves the power transmission coil 81, which is not currently charging, to a position corresponding to the location information of the second power receiving terminal 9 via the mobile system M1, starts supplying power (charging) to the second power receiving terminal 9, and stores the location information of the first power receiving terminal 9 in a memory (not shown) (step S19).

[0136] As described above, according to this third embodiment, even when there are powered devices already receiving power, by using a suitable threshold voltage (any of threshold voltages thA to thC) for each of the first search coils 310 and second search coils 320, the influence of power supply on the position detection device 3 can be suppressed, and more positions can be secured in which the position of new powered devices can be correctly detected. Alternatively, the number of power transmission coils can be increased to supply power to more powered terminals in the same area.

[0137] [4] Fourth Embodiment In each of the above embodiments, the configuration included a plurality of first search coils 310 arranged in a plurality of rows along a first direction and a plurality of second search coils 320 arranged in a plurality of rows along a second direction intersecting the first direction. However, in this fourth embodiment, at least one of the first search coils 310 or the second search coils 320 is arranged in multiples in the same row. Figure 15 is an explanatory diagram of a specific example of the fourth embodiment. In Figure 15, the multiple first search coils 310, arranged in multiple rows along the first direction, are arranged in pairs in the same row, while the multiple second search coils 320, arranged in multiple rows along the second direction intersecting the first direction, are arranged in pairs in the same row. According to this fourth embodiment, when applied to the first and second embodiments, the number of ineffective search coils can be reduced, and position detection can be performed more reliably. Furthermore, when applied to any of the first to third embodiments, It can perform position detection with high accuracy.

[0138] While embodiments of this disclosure have been described above, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel 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 novel embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents. [Explanation of symbols]

[0139] 1. Wireless power supply device 3. Position detection device 5 X-axis drive unit 8 Power transmission section 8A No. 1 Transmission Section 8B Second Power Transmission Section 9. Power receiving terminal 14 Controllers 31 First detection unit 32 Second detection unit 81 Power transmission coil 81A No. 1 Transmission Coil 81B Second transmission coil 83 Power transmission circuit 84 Communication Circuit 91 Power receiving coil 94 Communication Circuit 141 Identification Unit 142 Movement Control Unit 210 Power transmission area 211 Display device 310 First Search Coil 320 Second Search Coil E1 Echo signal N1 Noise signal P1 pulse signal for position detection thA~thC threshold voltage

Claims

1. Multiple power transmission coils, Multiple first detection coils arranged in multiple rows along a first direction, Multiple second detection coils arranged in multiple rows along a second direction intersecting the first direction, A position detection device that outputs position detection pulse signals to the first detection coil and the second detection coil, and receives echo signals from the powered device via the first detection coil and the second detection coil, and detects the position of the powered coil of the powered device placed on a predetermined charging surface based on the detection voltages in the first detection coil and the second detection coil, A power transmission coil moving device moves one of several power transmission coils to a position opposite to the power receiving coil detected by the position detection device, The system includes a power supply unit that supplies power to the power transmission coil, The position detection device, when power is already being supplied via one of the power transmission coils, disables and excludes from detection the first detection coil and the second detection coil located within a predetermined distance from the mounting position of the power receiving coil to which power is being supplied. Wireless power supply device.

2. The predetermined distance is set to be longer the greater the transmission power from the power transmission coil. The wireless power supply device according to claim 1.

3. The position detection device detects the position of the power receiving coil of the powered device by comparing the detection voltage in the first detection coil and the second detection coil with a predetermined threshold voltage. The wireless power supply device according to claim 1.

4. The threshold voltage is set to be higher the greater the transmitted power from the power transmission coil. The wireless power supply device according to claim 3.

5. Multiple threshold voltages are provided. The threshold voltage is set to a higher voltage the greater the transmitted power from the power transmission coil. The wireless power supply device according to claim 3.

6. The first detection coils are arranged in multiples in each row along the first direction. The wireless power supply device according to claim 1.

7. The second detection coils are arranged in multiples in each row along the second direction. The wireless power supply device according to claim 1.

8. When the position detection device disables the first detection coil or the second detection coil and excludes them from the detection target, The output of the position detection pulse signal to the first detection coil or the second detection coil to be disabled is stopped. The wireless power supply device according to claim 1.

9. When the position detection device disables the first detection coil or the second detection coil and excludes them from the detection target, The echo signal from the power supply device input via the first detection coil or the second detection coil to be disabled is excluded from the detection process. The wireless power supply device according to claim 1.

10. Multiple power transmission coils, Multiple first detection coils arranged in multiple rows along a first direction, Multiple second detection coils arranged in multiple rows along a second direction intersecting the first direction, A position detection device that outputs position detection pulse signals to the first detection coil and the second detection coil, and receives echo signals from the powered device via the first detection coil and the second detection coil, and detects the position of the powered coil of the powered device placed on a predetermined charging surface based on the detection voltages in the first detection coil and the second detection coil, A power transmission coil moving device moves one of several power transmission coils to a position opposite to the power receiving coil detected by the position detection device, The system includes a power supply unit that supplies power to the power transmission coil, At least one of the first detection coil or the second detection coil is arranged in multiples in the same row. The position detection device, when power is already being supplied via one of the power transmission coils, disables and excludes from detection the first detection coil and the second detection coil located within a predetermined distance from the mounting position of the power receiving coil to which power is being supplied. Wireless power supply device.

11. The predetermined distance is set to be longer the greater the transmission power from the power transmission coil. The wireless power supply device according to claim 10.

12. The position detection device detects the position of the power receiving coil of the powered device by comparing the detection voltage in the first detection coil and the second detection coil with a predetermined threshold voltage. The wireless power supply device according to claim 10.

13. The threshold voltage is set to a higher voltage the greater the transmitted power from the power transmission coil. The wireless power supply device according to claim 12.

14. Multiple threshold voltages are provided. The threshold voltage is set to a higher voltage the greater the transmitted power from the power transmission coil. The wireless power supply device according to claim 13.

Images