RECEIVING UNIT, TRANSMISSION UNIT, POWER TRANSMISSION SYSTEM AND METHOD FOR WIRELESS POWER TRANSMISSION

Abstract

The invention firstly relates to a receiver unit (200), configured to interact for wireless energy transfer with a transmitter unit (100) separate from the receiving unit, said transmitter unit (100) comprising a primary coil (L.sub.1) that can be supplied with a supply voltage (U.sub.V), wherein the receiver unit (200) comprises a secondary coil (L.sub.2) to which a DC link capacitor (C.sub.Z) and an energy storage unit (220) are connected by a power converter (210). According to the invention, the receiver unit (200) contains a device (240) for actuating the power converter (210) when a voltage is applied on the DC link capacitor (C.sub.Z) for supplying an alternating current (I) flowing through the secondary coil (L.sub.2) by actuating the power converter (210) to generate an energy pulse (E.sub.P). Secondly, the invention relates to a transmitter unit (100) configured to interact with a receiver unit (200) separate from the transmitter unit for wireless energy transfer, wherein the transmitter unit (100) comprises a primary coil (L.sub.1) that can be supplied with a supply voltage (U.sub.V). There is a device (140) in the transmitter unit for detecting a voltage (U.sub.I) induced in the primary coil when the supply voltage is disconnected from the primary coil (L.sub.1).

Claims

1-14. (canceled)

15. A system for wireless power transmission, the system comprising: a transmitter unit comprising a primary coil and a voltage detecting device, the primary coil configured to be supplied with a supply voltage, and the voltage detecting device configured to detect an induced voltage in the primary coil when the primary coil is disconnected from the supply voltage; and a receiver unit comprising a secondary coil and a processor, the secondary coil connected to a DC link capacitor and an energy storage unit via a power converter, and the processor configured to control the power converter when a voltage is applied by the energy storage unit to the DC link capacitor such that a current flowing through the secondary coil is configured to generate an energy pulse, wherein the energy pulse causes the induced voltage in the primary coil, wherein the voltage detecting device is configured to control an inverter configured to apply the supply voltage to the primary coil for the wireless power transmission from the primary coil when a value of the induced voltage in the primary coil or a value derived therefrom satisfies a predetermined condition, wherein the inverter is configured to prevent the wireless power transmission from the primary coil when the value of the voltage induced in the primary coil or the value derived therefrom does not satisfy the predetermined condition, and wherein the processor of the receiver unit is configured to repeatedly generate the energy pulse via the power converter until a charging process of the energy storage unit by the transmitter unit is detected.

16. The system of claim 15, wherein the power converter is an active rectifier.

17. The system of claim 15, wherein the receiver unit is configured to be positioned underneath a skin.

18. The system of claim 15, wherein the transmitter unit is configured to be positioned on a skin.

19. The system of claim 15, wherein the processor of the receiver unit is configured to repeatedly generate the energy pulse periodically at a predetermined time interval.

20. The system of claim 19, wherein the predetermined time interval is 30 seconds.

21. The system of claim 15, wherein a duration of the energy pulse does not exceed one second.

22. A method for wireless power transmission , the method comprising: detecting energy pulses generated at a receiver unit, wherein the energy pulses cause an induced voltage in a primary coil of a transmitter unit; determining a value of the induced voltage at the primary coil; determining that the value of the induced voltage at the primary coil satisfies a predetermined condition; and wirelessly transmitting power to the receiver unit, wherein the receiver unit is configured to repeatedly generate the energy pulses until a charging process of an energy storage unit of the receiver unit is detected.

23. The method of claim 22, wherein the receiver unit is configured to repeatedly generate the energy pulses at a predetermined time interval.

24. The method of claim 23, wherein the predetermined time interval is 30 seconds.

25. The method of claim 22, wherein a duration of each of the energy pulses does not exceed one second.

26. The method of claim 22, wherein the transmitter unit is configured to be positioned proximate to the receiver unit until the induced voltage reaches a threshold value.

27. The method of claim 22, wherein the transmitter unit is configured to be positioned proximate to the receiver unit until the transmitter unit transfers energy wirelessly to the receiver unit.

28. The method of claim 22 further comprising: detecting proximal positioning of the receiver unit relative to the transmitter unit.

29. A system for wireless power transmission, the system comprising: a transmitter unit comprising an inverter and a primary coil configured to be supplied with a supply voltage; and a receiver unit comprising a secondary coil and an energy storage unit, the energy storage unit configured to cause a current flowing through the secondary coil and generate an energy pulse, the energy pulse configured to cause an induced voltage in the primary coil, wherein when a value of the induced voltage in the primary coil satisfies a predetermined condition, the inverter of the transmitter unit is configured to apply the supply voltage to the primary coil for wireless power transmission between the transmitter unit and the receiver unit.

30. The system of claim 29, wherein when the value of the induced voltage in the primary coil does not satisfy the predetermined condition, the inverter prevents the wireless power transmission between the transmitter unit and the receiver unit.

31. The system of claim 29, wherein the energy storage unit is configured to repeatedly generate the energy pulse until a charging process of the energy storage unit is detected.

32. The system of claim 29, wherein the energy storage unit is configured to generate the energy pulse at a predetermined interval.

33. The system of claim 32, wherein the predetermined interval is 30 seconds.

34. The system of claim 32, wherein a duration of the energy pulse does not exceed one second.

Description

[0032] The figures show:

[0033] FIG. 1 a schematic representation of a transmitter unit and a receiver unit in an energy transfer system; and

[0034] FIG. 2 a schematic representation of voltage and current profiles during operation of the energy transfer system.

[0035] FIG. 1 shows a schematic representation of an energy transfer system 300 according to the invention for wireless energy transfer in a preferred embodiment. The energy transfer system has a transmitter unit 100 and a receiver unit 200 separated therefrom, each according to a preferred embodiment of the invention.

[0036] The transmitter unit 100 comprises a primary coil L.sub.1, to which an inverter 110 can supply a voltage U.sub.V, said inverter having four semiconductor switches, for example MOSFETs or bipolar transistors, designated as S.sub.1 to S.sub.4. In addition, a pre-filter 120 and a compensation capacitance with unspecified components are arranged between the inverter 110 and the primary coil L.sub.1. The compensation capacitance is used for resonant actuation (actuation with the design frequency) as reactive power compensation.

[0037] When the voltage U.sub.V is applied and the inverter is suitably actuated, an alternating magnetic field can thus be generated by means of the coil L.sub.1.

[0038] The receiver unit 200 has a secondary coil L.sub.2 with compensation capacitance, to which a DC link capacitor C.sub.Z is connected by a power converter 210. In turn, an energy storage unit 220 is connected to the DC link capacitor C.sub.Z by means of two semi-conductor switches S.sub.5 and S.sub.6, which can for example be configured as MOSFETs or bipolar transistors, and together with an inductance and a capacitance act as a buck converter, in particular. A load can be connected, for example, on the indicated connections. An output voltage U.sub.out with an output current I.sub.out can be set on the energy storage unit, for example by using the mentioned buck converter.

[0039] The power converter 210 is designed as an active rectifier with four semiconductor switches, for example MOSFETs or bipolar transistors, designated as S.sub.1 to S.sub.4. The energy storage unit 220 can be a storage battery or a rechargeable battery, in particular.

[0040] The receiver unit 200 can now in particular be configured to be arranged or implanted underneath the skin indicated here as 310, and for example used for a cardiac or ventricular support system. In particular, the energy storage unit 220 can be used for the energy supply of such a cardiac or ventricular support system.

[0041] With the transmitter unit 100 positioned correspondingly outside or on the skin 310, and assuming corresponding positioning, a coupling is achieved between the primary coil L.sub.1 of the transmitter unit 100 and the secondary coil L.sub.2 of the receiver unit 200.

[0042] If the transmitter unit is now actuated or operated in such a way that an alternating magnetic field is generated by means of the primary coil L.sub.1, the coupling induces a voltage or current flow in the secondary coil L.sub.2. This, in turn, causes the DC link capacitor C.sub.Z to be charged.

[0043] In the context of the present invention, the receiver unit 200 is now configured to actuate the power converter 210 embodied as an active rectifier with voltage U.sub.Z applied on the DC link capacitor by the energy storage unit 220 such that an energy pulse, schematically indicated here as E.sub.P, is generated by means of the secondary coil L.sub.2. The power converter 210 configured as an active rectifier is thus actuated in particular in the sense of an inverter. However, it is also conceivable to actuate the power converter 210 configured as an active rectifier by applying only a short voltage pulse with a rising flank to the secondary coil L.sub.2 in order to generate a rising magnetic field.

[0044] A computing unit 240 integrated in the receiver unit 200 can be used, for example, for this actuation of the power converter 210 configured as an active rectifier. The computing unit 240 then forms a device designed to actuate the power converter 210 with a voltage applied by the energy storage unit 220 to the DC link capacitor C.sub.Z, such that an AC current I flowing through the secondary coil L.sub.2 is provided to generate an energy pulse E.sub.P.

[0045] In the context of the present invention, the transmitter unit 100 is configured to detect a voltage U.sub.I induced in the primary coil when the primary coil L.sub.1 is disconnected from the supply voltage U.sub.V. This induced voltage U.sub.I is in this case, for example, tapped across a resistor. A suitable voltage measuring device can also be used for this purpose, which can for example be provided in the computing unit 140 shown and integrated into the transfer unit 100.

[0046] However, it is also conceivable that the induced voltage is not, as shown, tapped after the rectification of the voltage or energy pulse induced in the primary coil L.sub.1, but rather is tapped or detected prior thereto. A suitable voltage measuring device can also be used for this purpose, which can for example be provided in the computing unit 140 shown and integrated in the transmitter unit 100.

[0047] The computing unit 140 thus forms a device for detecting a voltage U.sub.I induced in the primary coil when a supply voltage is disconnected from the primary coil L.sub.1.

[0048] If the value of the induced voltage U.sub.I is then below a predetermined threshold value, it can be assumed that the two coils L.sub.1 and L.sub.2 are positioned sufficiently precisely to one another and the charging process of the energy storage unit 220 can be started. For this purpose, the supply voltage U.sub.V can then again first be applied to the primary coil L.sub.1, and the active rectifier 210 can again be operated as a rectifier in the receiver unit 200.

[0049] The computing unit 140 integrated into the transmitter unit 100 causes a predetermined function to be carried out due to the induced voltage U.sub.I detected in the primary coil L.sub.1 when a supply voltage is disconnected, said function consisting of the application of the supply voltage U.sub.V to the primary coil L.sub.1 and the actuation of the primary coil L.sub.1 for wireless energy transfer.

[0050] The inverter 110 is then actuated by means of the computing unit 140 such that the supply voltage U.sub.V is applied to the primary coil L.sub.1 and a current flow is generated in the primary coil L.sub.1 for wireless energy transfer when a value of the voltage U.sub.I induced in the primary coil or a metric derived therefrom exceeds or falls below a predetermined threshold value.

[0051] The computing unit 140 is thus a device that serves to perform a predetermined function due to the induced voltage U.sub.I detected in the primary coil L.sub.1 when the supply voltage is disconnected.

[0052] FIG. 2 schematically shows voltage and current graphs when using an energy transfer system according to a preferred embodiment of the invention. For this purpose, the upper diagram shows in V the voltage U.sub.I induced in the transmitter unit, the middle diagram shows a current I in A in the oscillating circuit formed in the receiver unit with the secondary coil L.sub.2, and the bottom diagram shows the associated voltage U in V applied to this oscillating circuit and corresponding to this current I, each plotted over time t in s.

[0053] It can be seen here that a voltage in the primary coil can be induced by a suitable actuation of the receiver unit 200 or the secondary coil L.sub.2 and the energy pulse E.sub.P generated therewith, with which, for example, a capacitor connected to the primary coil (which can be, for example, connected in parallel to the supply voltage) is charged.

[0054] Such an energy pulse can then for example be repeatedly generated at predetermined time intervals of, for example, 30 s, and, as soon as a sufficient value of the induced voltage is measured by the transmitter unit, the transmitter unit can transition into the regular operating mode for energy transfer.

[0055] The duration of such an energy pulse can be selected very briefly, for example at most one second, so that it can be ensured that no undesirable heating occurs of metallic objects located in the vicinity.

[0056] It is conceivable, for example, that the transmitter unit is repositioned relative to the receiver unit until the induced voltage reaches the predetermined threshold value and/or until the charging process starts automatically or in an automated fashion. Furthermore, it can be determined that a positioning test has been carried out and another positioning method can alternatively be used. In this case, the power pulse only serves as a start signal for the transmitter unit.

[0057] In addition, it is thus made possible that the charging process can start automatically or in an automated fashion strictly by positioning the transmitter unit and in particular without further intervention, because the transmitter unit is given a start signal by the energy pulse.

[0058] In summary, the following preferred features of the invention should be noted, in particular:

[0059] The invention firstly relates to a receiver unit 200 configured to interact for wireless energy transfer with a transmitter unit 100 separate from the receiver unit, said transmitter unit 100 having a primary coil L.sub.1 that can be supplied with a supply voltage U.sub.V, wherein the receiver unit 200 has a secondary coil L.sub.2 to which a DC link capacitor C.sub.Z and an energy storage unit 220 are connected by a power converter 210. The receiver unit 200 contains a device 240 for actuating the power converter 210 with a voltage applied to the DC link capacitor C.sub.Z for supplying an AC current I flowing through the secondary coil L.sub.2 by actuating the power converter 210 in order to thereby generate an energy pulse E.sub.P.

[0060] Secondly, the invention relates to a transmitter unit 100 configured to interact for wireless energy transfer with a receiver unit 200 separate from the transmitter unit, wherein the transmitter unit 100 comprises a primary coil L.sub.1 that can be supplied with a supply voltage U.sub.V. There is a device 140 in the transmitter unit for detecting a voltage U.sub.I induced in the primary coil when the supply voltage is disconnected from the primary coil L.sub.1.

[0061] The invention relates, in particular, to the aspects specified in the following clauses:

[0062] 1. Receiver unit (200), configured to interact for wireless energy transfer with a transmitter unit (100) separate from the receiving unit, said transmitter unit (100) comprising a primary coil (L.sub.1) that can be supplied with a supply voltage (U.sub.V), wherein the receiver unit (200) comprises a secondary coil (L.sub.2) to which a DC link capacitor (C.sub.Z) and an energy storage unit (220) are connected by a power converter (210),

characterized in that [0063] the receiver unit (200) is configured to actuate the power converter (210) when voltage is applied by the energy storage unit (220) to the DC link capacitor (C.sub.Z) such that an energy pulse (E.sub.P) is generated by means of the secondary coil (L.sub.2).

[0064] 2. Receiver unit (200) according to clause 1, wherein the power converter (210) is configured as an active rectifier.

[0065] 3. Receiver unit (200) according to clause 1 or 2 configured to generate the energy pulse (E.sub.P) repeatedly, in particular at predetermined time intervals.

[0066] 4. Receiver unit (200) according to clause 3, configured to repeatedly generate the energy pulse (E.sub.P) until a charging process of the energy storage unit (220) carried out by the transmitter unit (100) is detected.

[0067] 5. Receiver unit (200) according to any of the above clauses, designed to be arranged underneath the skin (310) in a human or animal body.

[0068] 6. Transmitter unit (100) configured to interact for wireless energy transfer with a receiver unit (200) separate from the transmitter unit, [0069] wherein the transmitter unit (100) comprises a primary coil (L.sub.1) that can be supplied with a supply voltage (U.sub.V),
characterized in that [0070] the transmitter unit (100) is configured to detect a voltage (U.sub.I) induced in the primary coil when a primary coil (L.sub.1) is disconnected from the supply voltage and to perform at least one predetermined function based thereon.

[0071] 7. Transmitter unit (100) according to clause 6, wherein the at least one predetermined function comprises the application of the supply voltage (U.sub.V) to the primary coil (L.sub.1) and the actuation of the primary coil (L.sub.1) for wireless energy transfer.

[0072] 8. Transmitter unit (100) according to clause 6 or 7, configured to apply the supply voltage (U.sub.V) to the primary coil (L.sub.1) and to actuate the primary coil (L.sub.1) for wireless energy transfer when a value of the voltage (U.sub.I) induced in the primary coil or a metric derived therefrom exceeds or falls below a predetermined threshold value.

[0073] 9. Transmitter unit (100) according to clause 8, configured to not actuate the primary coil (L.sub.1) for wireless energy transfer when the value of the voltage induced in the primary coil (U.sub.I) or the metric derived therefrom does not exceed or does not fall below the predetermined threshold value.

[0074] 10. Transmitter unit (100) according to any of the clauses 6 to 9, designed to be arranged on the skin (310) outside of a human or animal body.

[0075] 11. Energy transfer system (300) for wireless energy transfer with a transmitter unit (100) according to any of clauses 6 to 10 and a receiver unit (200) separate therefrom according to any of clauses 1 to 5.

[0076] 12. Method for wireless energy transfer by means of an energy transfer system (300) according to clause 11, wherein an energy transfer is started automatically when an energy pulse (E.sub.P) generated by means of the receiver unit (200) in the primary coil (L.sub.1) of the transmitter unit (100) induces a voltage, and when a value of the voltage (U.sub.I) induced in the primary coil or a metric derived therefrom exceeds or falls below a predetermined threshold value.

LIST OF REFERENCE SYMBOLS

[0077] 100 Transmitter unit [0078] 110 Inverter [0079] 120 Pre-filter [0080] 140 Computing unit [0081] 200 Receiver unit [0082] 210 Power converter/rectifier [0083] 220 Energy storage unit/Energy storage [0084] 240 Computing unit [0085] 300 Energy transfer system [0086] 310 Skin [0087] C.sub.Z z DC link capacitor [0088] E.sub.P Energy pulse [0089] I Current [0090] I.sub.out Output current [0091] L.sub.1 Primary coil [0092] L.sub.2 Secondary coil [0093] S.sub.1 to S.sub.6 Semiconductor switch [0094] t Time [0095] U Voltage [0096] U.sub.out Output voltage [0097] U.sub.I Induced voltage [0098] U.sub.V Supply voltage [0099] U.sub.Z Voltage