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EP-4738651-A1 - ALIGNMENT CONTROL FOR WIRELESS POWER SYSTEM AND POWER TRANSMISSION SYSTEM

EP4738651A1EP 4738651 A1EP4738651 A1EP 4738651A1EP-4738651-A1

Abstract

The invention concerns a wireless power system (1), comprising a first unit (10, 20) including a pad (11, 21) configured to wirelessly transmit or receive power and a wireless communication unit (12, 22); and a control unit (2), wherein the pad (11, 21) is configured to wirelessly transmit or receive power to or from a second unit (10, 20), and the wireless communication unit (12, 22) is configured to receive a communication signal (32) from the second unit (10, 20), and wherein the control unit (2) is configured detect at least one phase value of the communication signal (32) and to determine, based on the detected phase value, a relative position of the wireless communication unit (12, 22) and the second unit (10, 20). Furthermore, the invention concerns a power transmission system (100) comprising the wireless power system (1) and the second unit (10, 20).

Inventors

  • LOESER, LEON ANDREA
  • Enderlin, Jonas

Assignees

  • Delta Electronics (Thailand) Public Co., Ltd.

Dates

Publication Date
20260506
Application Date
20241029

Claims (15)

  1. Wireless power system (1), comprising: • a first unit (10, 20) including a pad (11, 21) configured to wirelessly transmit or receive power and a wireless communication unit (12, 22); and • a control unit (2); • wherein the pad (11, 21) is configured to wirelessly transmit or receive power to or from a second unit (10, 20), and the wireless communication unit (12, 22) is configured to receive a communication signal (32) from the second unit (10, 20), and wherein • the control unit (2) is configured detect at least one phase value of the communication signal (32) and to determine, based on the detected phase value, a relative position of the wireless communication unit (12, 22) and the second unit (10, 20).
  2. Wireless power system (1) according to claim 1, wherein the control unit (2) is configured to calculate a phase-relation as the phase-value, especially a phase-difference, between multiple receptions of the communication signal (32) and to determine said relative position based on the calculated phase-relation.
  3. Wireless power system (1) according to claim 2, wherein the control unit (2) is configured to calculate a time-phase-relation, as the phase-relation, between multiple receptions at respectively different times, especially during relative movement of the wireless communication unit (12, 22) and the second unit (10, 22).
  4. Wireless power system (1) according to claim 3, wherein the control unit (2) is configured to calculate at least two time-phase-relations, respectively between two receptions at different times, and to calculate a time-dependent change between the time-phase-relations.
  5. Wireless power system (1) according to claim 4, wherein the control unit (2) is configured to compare the time-dependent change with input and/or predetermined movement information, especially comprising amount and/or direction, of the wireless communication unit (12, 22).
  6. Wireless power system (1) according to any one of the foregoing claims, wherein the wireless communication unit (12, 22) comprises at least one main communication antenna (13, 23) for transmitting and receiving the communication signal (32), and wherein the wireless communication unit (12, 22) comprises at least one, especially two to four, auxiliary sensing antennas (24) for detecting the relative position.
  7. Wireless power system (1) according to claim 6, wherein the control unit (2) is configured to calculate a space-phase-relation, as the phase value, between multiple receptions of the communication signal (32) at respectively different antennas, of the at least one main communication antenna (13, 23) and the at least one auxiliary sensing antenna (24), and to determine said relative position based on the calculated space-phase-relation.
  8. Wireless power system (1) according to claim 7, wherein the control unit (2) is configured to calculate a difference between phases of the multiple receptions, as the space-phase-relation, and to determine a distance between the respectively different antennas to the second unit (10, 20).
  9. Wireless power system (1) according to any one of claims 6 to 8, wherein a plurality of auxiliary sensing antennas (24) are arranged surrounding, especially symmetrically surrounding, the main communication antenna (23).
  10. Wireless power system (1) according to any one of the foregoing claims, wherein the control unit (2) is further configured to detect a signal strength, especially a maximum amplitude and/or a maximum peak-to-peak value, of the communication signal (32) and to determine, based on the detected signal strength and on the detected phase value, the relative position of the wireless communication unit (12, 22) and the second unit (10, 20).
  11. Wireless power system (1) according to any one of the foregoing claims, wherein the wireless communication unit (12, 22) is separated by a distance to the second unit (10, 20) and the control unit (2) is configured to: • at or below a first predetermined distance value, detect the relative position using the communication signal (32); and/or • at or below a second predetermined distance value, transfer data using the communication signal (32).
  12. Wireless power system (1) according to claim 11, wherein the first predetermined distance value is larger than the second predetermined distance value, and wherein the control unit (2) is configured to transfer data using the communication signal only below the second predetermined distance value.
  13. Wireless power system (1) according to claim 11 or claim 12, wherein the control unit (2) is configured to control the pad (11, 21) to wirelessly transfer and/or receive power at or below a third predetermined distance value, wherein the third predetermined distance value is smaller than the second predetermined distance value.
  14. Power transmission system (100), comprising the wireless power system (1) according to any one of the foregoing claims and the second unit (10, 20), wherein the first unit (10, 20) is a secondary unit (20), the pad (11, 21) is a secondary pad (21) configured to wirelessly receive power, and the wireless communication unit (12, 22) is a secondary wireless communication unit (22), wherein the second unit (10, 20) is a primary unit (10) including a primary pad (11) for wireless power transmission and a primary wireless communication unit (12).
  15. Power transmission system (100) according to claim 14, wherein the primary wireless communication unit (12) comprises at least one primary main communication antenna (23) for transmitting and receiving the communication signal (32), and wherein the primary wireless communication unit (12) comprises at least one, especially two to four, primary auxiliary sensing antennas (24) for detecting the relative position.

Description

Field of the Invention The invention concerns a wireless power system and a power transmission system. Background of the Invention Generally, wireless power systems for wirelessly transferring power between a transmission unit and a reception unit (commonly also referred to as "primary unit" and "secondary unit" or "TX/RX") are known. Therein, it is commonly a challenge to position these with respect to one another for efficient power transmission, commonly referred to as "alignment". Attempts to overcome this challenge are known from for example US2013/0033224 A1, US10,072,947, US2020/0290467 A1, and US2017/0111088 A1. However, these known systems have multiple drawbacks. For one, as described in for example US2013/0033224 A1 or US2020/0290467 A1, common solutions include multiple additional coils which also receive power on the reception side, wherein electrical values such as voltages induced in these or resonant frequencies are compared for determining alignment. This, however, has the drawback in that the additional coils are expensive and reduce efficiency both with respect to heat and electrical usage of transmitted power. Furthermore, their accuracy is relatively low. The conventionally known alignment methods are generally either based on additional sensors or beacons, which are costly, bulky, and inefficient, or are based on the received power from the wireless transmission, which is however inaccurate in providing two- or three-dimensional alignment between the primary pad and the secondary pad and reduces transmission efficiency. Summary It is an object of the present invention to overcome these deficiencies. In particular, it is an object of the present invention to provide a wireless power system which can accurately and efficiently determine a relative position of its first unit relative to a second unit. It is further an object of the present invention to provide a power transmission system with a first unit and a second unit which can accurately and efficiently determine a relative position between the first unit and the second unit. The solution of this object is achieved by the features of the independent claim. The dependent claims contain advantageous embodiments of the present invention. In particular, the solution of these objects is achieved by the wireless power system according to claim 1. The wireless power system comprises a first unit including a pad configured to wirelessly transmit or receive power and a wireless communication unit. The first unit further includes a control unit. Therein, the pad is configured to wirelessly transmit or receive power to or from a second unit, and the wireless communication unit is configured to receive a communication signal from the second unit. The control unit is configured detect a phase value of the communication signal and is configured to determine, based on the detected phase value, a relative position of the wireless communication unit to the second unit. In other words, the control unit is configured to determine the relative position or distance of the wireless communication unit, which is included in the first unit of the wireless power system, to an external second unit. For example, the first unit may be a reception unit (secondary side unit), and the control unit is configured to determine its alignment with a transmission unit (primary side unit). In some examples, the first unit is comprised by a vehicle, whereas the second unit is comprised by an external ground unit or by an external wall unit. Of course, the same holds true for examples in which the first unit is a ground unit or a wall unit and the second unit is an external vehicle-mounted unit. In particular, it is an advantage of the present invention that the wireless power system especially comprises only the first unit. Thereby, the alignment can be carried out by the control unit largely independent from configurations of the second unit. Preferably, the second unit is configured to at least transmit, especially also receive, the communication signal. In the sense herein, the term "relative position" refers to an at least one-dimensional, preferably two-dimensional, more preferably three-dimensional, distance from the first unit to the second unit. Preferably, the absolute position of one of the first unit and second unit is known. For example, one of the units is disposed in a predetermined location, for example in a parking lot or at a charging station. Thereby, an absolute position of the units can thereby be determined via the detected relative position and the known predetermined location. Furthermore, the term "relative position", in some preferable embodiments, also refers to an alignment angle (or spatial angle) between the first unit and the second unit. In the sense herein, power transmission and/or reception will in some instances be abbreviated to "power transfer". Herein, the wireless power system uses the phase value of the communication signal to deter