WIRELESS POWER-SUPPLYING SYSTEM, POWER-RECEIVING DEVICE, AND POWER-TRANSMITTING DEVICE

• US 20170018973A1
• Filed: 09/29/2016
• Published: 01/19/2017
• Est. Priority Date: 05/30/2014
• Status: Active Grant

• Current Assignee: IHI Corporation
• Original Assignee: IHI Corporation
• Inventors: MURAYAMA, Takahiko, ARAKI, Jun
• Granted Patent: US 10,305,334 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B60L 53/126 Methods for pairing a vehicle and a charging station, e.g. establishing a one-to-one relation between a wireless power transmitter and a wireless power receiver
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/00712 the cycle being controlled or terminated in response to electric parameters
• CPC Class Codes: H02M 3/01 Resonant DC/DC converters
• CPC Class Codes: H02M 3/33573 Full-bridge at primary side of an isolation transformer
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

A wireless power-supplying system includes a power-transmitting device that transmits power in a wireless manner and a power-receiving device that receives the power and supplies the received power to a load, the power-receiving device includes a switch that switches the connection to the load and a load circuit that is supplied with the power when the switch is in an open state, and the wireless power-supplying system includes a control unit that performs a position determining process of determining whether the power-transmitting device and the power-receiving device have a positional relationship in which power is suppliable to the load on the basis of at least one of power, voltage, and current in at least one of the power-transmitting device and the power-receiving device when the power is supplied to the load circuit.

Claims

1. A wireless power-supplying system comprising:

a power-transmitting device that transmits power in a wireless manner; and

a power-receiving device that receives the power and supplies the received power to a load,

wherein the power-receiving device includes

a switch that switches connection to the load, and

a load circuit that is supplied with the power when the switch is in an open state, and

wherein the wireless power-supplying system includes a control unit that performs a position determining process of determining whether the power-transmitting device and the power-receiving device have a positional relationship in which power is suppliable to the load on the basis of at least one of power, voltage, and current in at least one of the power-transmitting device and the power-receiving device when the power is supplied to the load circuit.

2. The wireless power-supplying system according to claim 1, wherein the control unit controls the power-transmitting device so as to output a lower voltage when the load circuit is supplied with power compared to a case in which the load is supplied with power.

3. The wireless power-supplying system according to claim 1, wherein impedance of the load circuit is a rated impedance of the load.

4. The wireless power-supplying system according to claim 1, wherein the power-transmitting device includes:

a transmitting-side power converter that converts power supplied from the outside into DC power; and

an inverter circuit that converts the DC power from the transmitting-side power converter into AC power, and

wherein the control unit performs the position determining process on the basis of at least one of power, voltage, and current in the transmitting-side power converter or the inverter circuit.

5. The wireless power-supplying system according to claim 4, wherein the control unit calculates input power on the basis of a voltage and a current of a voltage converter or the inverter circuit and performs the position determining process on the basis of the input power.

6. The wireless power-supplying system according to claim 4, wherein the control unit calculates output power on the basis of a voltage and a current of the load circuit and performs the position determining process on the basis of the output power.

7. The wireless power-supplying system according to claim 4, wherein the control unit:

calculates input power on the basis of a voltage and a current of the transmitting-side power converter or the inverter circuit,

calculates output power on the basis of a voltage and a current of the load circuit,

calculates power efficiency on the basis of the input power and the output power, and

performs the position determining process on the basis of the power efficiency.

8. The wireless power-supplying system according to claim 4, wherein the control unit performs the position determining process on the basis of a voltage of the load circuit.

9. The wireless power-supplying system according to claim 4, wherein the control unit performs the position determining process on the basis of a current of the load circuit.

10. The wireless power-supplying system according to claim 4, wherein the control unit calculates transmitting-side input impedance on the basis of a voltage and a current input to the inverter circuit and performs the position determining process on the basis of the transmitting-side input impedance.

11. The wireless power-supplying system according to claim 10, wherein the control unit determines that the power-transmitting device and the power-receiving device have a positional relationship in which power is not suppliable to the load when the transmitting-side input impedance is greater than an upper limit which is determined on the basis of a withstanding voltage of an element in the wireless power-supplying system.

12. The wireless power-supplying system according to claim 10, wherein the control unit determines that the power-transmitting device and the power-receiving device have a positional relationship in which power is not suppliable to the load when the transmitting-side input impedance is less than a lower limit which is determined on the basis of a heatproof temperature of an element in the wireless power-supplying system.

13. The wireless power-supplying system according to claim 4, wherein the control unit performs the position determining process on the basis of a phase difference between a voltage and a current output from the inverter circuit.

14. A power-receiving device that receives power from a power-transmitting device in a wireless manner, the power-receiving device comprising:

a power converter that converts power from the power-transmitting device into power to be supplied to a load device;

a switch that is disposed between the power converter and the load device; and

a control unit that opens the switch to open connection between the power converter and the load device and determines whether a voltage of the power converter induced from transmission of power from the power-transmitting device is equal to or greater than a power-suppliable threshold value.

15. The power-receiving device according to claim 14, wherein a voltage of the power transmitted from the power-transmitting device when the switch is opened is lower than a voltage of the power transmitted from the power-transmitting device when the switch is closed.

16. The power-receiving device according to claim 14, wherein the power converter includes a rectifier circuit that rectifies power from the power-transmitting device and the voltage of the power converter is an output voltage of the rectifier circuit.

17. A power-transmitting device including an inverter circuit that converts DC power into AC power and a transmitting-side pad that generates a magnetic field on the basis of the AC power and supplying power to a power-receiving device in a wireless manner, the power-transmitting device comprising:

a control unit that determines whether a power efficiency linked value which is information indicated by input power or output power of the inverter circuit and is linked with power efficiency in the supplying of power is within a range in which a specified power efficiency is obtainable.

18. The power-transmitting device according to claim 17, wherein the control unit adjusts at least one of inductance and capacitance of the transmitting-side pad so that the power efficiency linked value will be within the range, when the power efficiency linked value is not within the range.

19. The power-transmitting device according to claim 17, wherein the power efficiency linked value is input impedance of the inverter circuit.

20. The power-transmitting device according to claim 17, wherein the power efficiency linked value is output impedance of the inverter circuit.

21. The power-transmitting device according to claim 17, wherein the power efficiency linked value is a phase difference between an output voltage and an output current of the inverter circuit.

22. The power-transmitting device according to claim 17, wherein the range is a range in which specified power efficiency is obtainable and in which it is possible that a withstanding voltage of an element of at least one of the inverter circuit and the transmitting-side pad is not exceeded.