Power transmission apparatus, and power transmitting device and power receiving device for the power transmission apparatus

• US 10,128,687 B2
• Filed: 07/11/2014
• Issued: 11/13/2018
• Est. Priority Date: 07/12/2013
• Status: Expired due to Fees

• Current Assignee: Toshiba Tec Corporation (Toshiba Corporation)
• Original Assignee: Toshiba Tec Corporation (Toshiba Corporation)
• Inventors: Usami, Yutaka
• Primary Examiner(s): Cavallari, Daniel
• Application Number:
  US14/328,859
• Publication Number:
  US 20150015081A1
• Time in Patent Office: 1,586 Days
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02M 3/01 Resonant DC/DC converters
• CPC Class Codes: H02M 3/33523 with galvanic isolation between input and output of both the power stage and the feedback loop
• CPC Class Codes: H04B 5/266 One coil at each side, e.g. with primary and secondary coils
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

There is provided a non-contact power transmission apparatus which can supply stable power from a power transmitting side to a power receiving side even if a load is changed. The power transmission apparatus transmits power from a power transmitting device to a power receiving device in a non-contact manner. The power transmitting device includes a series circuit which is connected to a direct-current power source, and includes a parallel resonance circuit including a first capacitor and a first inductor, and a switch element, a drive source to drive on or off the switch element, and a first series resonance circuit connected to a connection point between the parallel resonance circuit and the switch element and including a second inductor, a second capacitor and a power transmission coil. The power receiving device includes a second series resonance circuit including a power receiving coil paired with the power transmission coil and a third capacitor connected in series to the power receiving coil, and a rectifying circuit to rectify a voltage generated in the second series resonance circuit and to supply the voltage to a load circuit.

Claims

1. A power transmission apparatus for transmitting power from a power transmitting device to a power receiving device in a non-contact manner, wherein

the power transmitting device comprises:

a series circuit which is connected between a direct-current power source and a reference potential point, and includes a parallel resonance circuit including a first capacitor and a first inductor, and a switch element including a parasitic diode in parallel to a main current path;

a drive source to drive on or off the switch element; and

a first series resonance circuit which is connected to a connection point between the parallel resonance circuit and the switch element and includes a second inductor, a second capacitor and a power transmission coil, and

the power receiving device comprises;

a second series resonance circuit including a power receiving coil paired with the power transmission coil, and a third capacitor connected in series to the power receiving coil; and

a rectifying circuit to rectify a voltage generated in the second series resonance circuit and to supply the voltage to a load circuit.

2. The apparatus according to claim 1, wherein a resonance frequency f1 of the parallel resonance circuit is set to be 1.1 to 1.2 times a drive frequency f0 of the switch element, and a resonance frequency f2 of the first series resonance circuit is set to be 0.8 to 0.9 times f0.

3. The apparatus according to claim 1, wherein a resonance frequency f3 of the second series resonance circuit is set in a range of 0.9 to 1.0 (f3 ≠

f0) of a drive frequency f0 of the switch element.

5. The apparatus according to claim 1, wherein the parallel resonance circuit of the power transmitting device includes:

the first inductor and the first capacitor connected in parallel between the direct-current power source and an output end of the switch element.

6. The apparatus according to claim 1, wherein the parallel resonance circuit of the power transmitting device includes:

the first inductor connected between the direct-current power source and an output end of the switch element, and the first capacitor connected between the output end of the switch element and the reference potential point.

4. A power transmitting device for transmitting power to a power receiving device in a non-contact manner, comprising:

a series circuit which is connected between a direct-current power source and a reference potential point, and includes a parallel resonance circuit including a first capacitor and a first inductor, and a switch element including a parasitic diode in parallel to a main current path;

a drive source to drive on or off the switch element; and

a first series resonance circuit which is connected to a connection point between the parallel resonance circuit and the switch element and includes a second inductor, a second capacitor and a power transmission coil.

7. The apparatus according to claim 4, wherein a resonance frequency f1 of the parallel resonance circuit is set to be 1.1 to 1.2 times a drive frequency f0 of the switch element, and a resonance frequency f2 of the first series resonance circuit is set to be 0.8 to 0.9 times f0.

8. The apparatus according to claim 4, wherein the parallel resonance circuit includes:

the first inductor and the first capacitor connected in parallel between the direct-current power source and an output end of the switch element.

9. The apparatus according to claim 4, wherein the parallel resonance circuit includes:

the first inductor connected between the direct-current power source and an output end of the switch element, and the first capacitor connected between the output end of the switch element and the reference potential point.