Inductive Power Transmission Method

Abstract

A method of inductive power transmission by a transmitter and a receiver of an electrically operated device, the transmitter having at least one transmitter coil and the receiver having at least one receiver coil, a control for the power to be transmitted is provided in the transmitter, a minimum power is transmitted by the transmitter through the control at the start of a power transmission, the minimum transferring power is sufficiently dimensioned to activate a controller of the receiver of the electrically operated device. By influencing the field of the transmitter coil, the controller supplies data packets to the control that contain information about the electrically operated device so that an optimal power adapted to the power class of the device is transmitted by the transmitter.

Claims

1.-10. (canceled)

11. A method of inductive power transmission by a transmitter to a receiver of an electrically operated device, the transmitter having a control for power to be transmitted and at least one transmitter coil and the receiver having at least one receiver coil, the method comprising: transmitting a minimum power by the transmitter at a start of a power transmission, wherein the minimum power is configured to activate a controller of the receiver of the electrically operated device; receiving by the control, from the controller of the receiver, data packets that contain information about the electrically operated device by influencing a field of the transmitter coil; and transmitting a power adapted to a power class of the electrically operated device by the transmitter based at least in part on the data packets.

12. The method according to claim 11, wherein the information allows the control to: identify the electrically operated device; and rank the electrically operated device in a power class, wherein the power adapted to the power class is transmitted by the transmitter, and a fine adjustment of the power is carried out in the electrically operated device.

13. The method according to claim 11, wherein the transmitted power is reduced by a power class when an overvoltage occurs.

14. The method according to claim 11, wherein a plurality of transmitter coils are provided, and wherein the transmitter coils transmit the minimum power consecutively through the control, the method further comprising: switching by the control switches the plurality of transmitter coils for an optimum power transmission in which at least one of a coupling with the receiver coil and/an influencing of its electrical field is greatest.

15. Method according to claim 14, wherein the coils are arranged in more than one plane so as to overlap, wherein the transmitter coils of a first plane transmit the minimum power consecutively through the control and the overlapping transmitter coils of the next plane transmit the minimum power consecutively through the control; and wherein the control switches the transmitter coil for the optimal power transmission in which at least one of the coupling with the receiver coil and the influencing of its electric field is greatest.

16. The method according to claim 14, further comprising: interrupting the optimal power transmission of the switched transmitter coil at predeterminable time interval and the minimum power is applied to at least one of the transmitter coils adjacent to the previously switched transmitter coil and the transmitter coils overlapping the previously switched transmitter coil; and switching, by the control, the transmitter coil for the optimal power transmission in which at least one of the coupling with the receiver coil and the influencing of its electrical field is greatest.

17. The method according to claim 14, wherein a group of transmitter coils is switched.

18. The method according to claim 11, wherein the data packets contain base area information of the electrically operated device, whereupon a power adapted to the base area of the electrically operated device is transmitted by the transmitter.

19. The method according to claim 11, further comprising: increasing a base area of the electrically operated device by shielding material beyond an extent of the transmitter coil when the electrically operated device have a receiver coil with a base area having smaller dimensions than those of the transmitter coil.

20. The method according to claim 11, wherein a transmission of at least one training sequence precedes a data packet.

21. The method according to claim 15, further comprising: interrupting the optimal power transmission of the switched transmitter coil at predeterminable time interval and the minimum power is applied to at least one of the transmitter coils adjacent to the previously switched transmitter coil and the transmitter coils overlapping the previously switched transmitter coil; and switching, by the control, the transmitter coil for the optimal power transmission in which at least one of the coupling with the receiver coil and the influencing of its electrical field is greatest.

22. The method according to claim 11, wherein the electrically operated device is one of a laptop, a smartphone, and a tablet.

23. The method according to claim 11, further comprising supplying, by the controller of the receiver of the electrically operated device, the data packets that contain the information about the electrically operated device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The invention will be described more fully with reference to the drawing in which devices for carrying out the method are shown only schematically.

[0027] The sole FIGURE shows a transmitter 1 and an electrically operated device 2.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

[0028] As shown in the FIGURE, the transmitter 1 has a plurality of transmitter coils 3, 4, shown only schematically, which are arranged in two planes in an overlapping manner, for example, on the upper side and underside of a circuit board 5. A coil arrangement of this kind is ideally suited for integration in a worktop, in a tabletop of a conference table, or the like, for supplying power to electrically operated devices 2 placed thereon as indicated by arrow 6.

[0029] The control of the individual transmitter coils 3, 4, possibly also a controlling of transmitter coils 3, 4 in groups, is carried out as indicated by double arrow 7, toward the right in the FIGURE, by a matrix control 8 switched by a microcontroller. This matrix control 8 distributes the transmission power provided by a power stage 9, according to distributor 10, to an individual transmitter coil 3 or 4 or to a group of transmitter coils 3, 4 via a further interconnection, not shown.

[0030] For the inductive power transmission, the electrically operated device 2 has a corresponding receiver coil 12. When the device 2 is placed above the transmitter coils 3, 4 according to arrow 6 for an inductive power transmission, the power stage 9 is set to a minimum power output by a control 13 controlled by a microcontroller according to arrow 14.

[0031] In principle, the transmitter coils 3, 4 are then consecutively connected to the minimum power in each instance. This minimum power output is sufficient for activating, via the receiver coil 12 of the device 2 with associated receiver 15, a controller 16 through which the field of the transmitter coils 3, 4 is influenced.

[0032] As a consequence of the influencing, a transmission of information about the electrically operated device 2 takes place according to double arrow 7, toward the left in FIG. 1, to the control 13 via the matrix control 8 according to double arrow 17. In this way, the transmitter 1 can identify the device 2 and, in particular, also transmit an optimal power adapted to the power class of the device 2.

[0033] For example, if intermediate values should be necessary for an optimal supply, a fine adjustment of this kind takes place within the device 2. In case of an overvoltage event, the transmitted power is reduced by a power class.

[0034] For an optimal power transmission, the transmitter coil 3, 4 with the largest coupling to the receiver coil 9 is used by the control 13 according to double arrow 17 via the matrix control 8.

[0035] Since a plurality of transmitter coils 3, 4 is provided in two planes in the embodiment example, the control 13 will apply the minimum power supplied by power stage 9 first, for example, to the transmitter coils 3 of a first plane consecutively via the matrix control 8. It is then determined by the control 13 which of the coils 3 has undergone a maximum change of field. Thereupon, it will preferably again apply, via the matrix control 8, the minimum power only to the transmitter coils 4 of the next plane that overlap with the transmitter coil 3 of the first plane, and the coil 3, 4 of the two planes in which the change in the electrical field is the greatest is then chosen.

[0036] An approach of this type can also be adapted to groups of transmitter coils if the receiver coil 12 has a corresponding two-dimensional extension.

[0037] However, the base area of the receiver coil 12 is often comparatively small, often smaller than that of a transmitter coil 3, 4. The transmitted data packets will then contain information about the base area of the device 2, whereupon the power stage 9 is switched by the control 13 to the minimum power output which is then switched by the matrix control 8 to the relevant transmitter coil 3, 4. A maximum permissible inductive power transmission can be ensured in this way.

[0038] A demodulation of the change in field of a transmitter coil 3, 4 is required for reading out the information about, or status of, an electrically operated device 2. To ensure complete demodulation of a data packet with respect to time, it can further be provided that the transmission of the data packet is preceded by the transmission of a training sequence.

[0039] Thus, while there have shown and described and pointed out fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions and substitutions and changes in the form and details of the devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, it is expressly intended that all combinations of those elements and/or method steps which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Moreover, it should be recognized that structures and/or elements and/or method steps shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.