Contactless electricity supply device

• US 9,969,280 B2
• Filed: 05/23/2012
• Issued: 05/15/2018
• Est. Priority Date: 05/27/2011
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Maikawa, Kengo, Tanaka, Hiroshi, Imazu, Tomoya
• Primary Examiner(s): Siek, Vuthe
• Assistant Examiner(s): Lin, Aric
• Application Number:
  US14/119,536
• Publication Number:
  US 20140103871A1
• Time in Patent Office: 2,183 Days
• CPC Class Codes: B60L 53/12 Inductive energy transfer
• CPC Class Codes: B60L 53/122 Circuits or methods for driving the primary coil, e.g. supplying electric power to the coil
• CPC Class Codes: B60L 53/124 Detection or removal of foreign bodies
• 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 2310/48 for electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: H02J 50/10 using inductive coupling
• 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 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• 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 contactless electric power supply device 100 to charge a battery 28 of a vehicle includes a power transmitting circuit 101 having a power transmitting coil 12 and a charging circuit 201 having a power receiving coil 22. An electric power is transmitted from power transmitting coil 12 to power receiving coil 22 in a contactless manner. When the vehicle approaches power supply device 100, a trial power supply in which a electric power transmission through a minute electric power is carried out is executed and a power transmission efficiency from power transmitting coil 12 to power receiving coil 22 is estimated on a basis of a current flowing through power transmitting circuit 101. From this power transmission efficiency, a determination of whether power receiving coil 22 falls in a range in which battery 28 is chargeable with respect to power transmitting coil 12 is made.

Claims

1. A contactless power supply device for transmitting an electric power from a first coil to a second coil in a contactless manner by at least a magnetic coupling, comprising:

a power transmitting circuit including the first coil;

a sensor configured to measure a current flowing through the power transmitting circuit or to measure a voltage applied to the power transmitting circuit;

a battery providing a power source of a vehicle;

a charging circuit including the second coil and configured to charge the battery;

an informing device; and

a control section in communication with the sensor, the control section being configured to;

determine an input electric power of the power transmitting circuit from at least either one of values from a detected current or a detected voltage detected by the sensor;

estimate a power transmission efficiency from the first coil to the second coil on a basis of a correlation between the power transmission efficiency from the first coil to the second coil and the input electric power such that as the input electric power becomes higher, the estimated power transmission efficiency becomes higher;

determine that a positional deviation between the first coil and the second coil falls in a range in which the battery is chargeable, in a case where the power transmission efficiency estimated by the control section is higher than a predetermined value;

based on the determination that the positional deviation falls in the range in which the battery is chargeable, control the informing device to indicate that the charging is allowed; and

in response to the indication that the charging is allowed, enable a user of the vehicle to confirm via the informing device that the control section controls the charging circuit to charge the battery.

2. The contactless power supply device as claimed in claim 1, further comprising a switch connected between the battery and the charging circuit wherein the switch is in an off state during a traveling of the vehicle.

3. The contactless power supply device as claimed in claim 1, wherein the control section is further configured to estimate the power transmission efficiency during a traveling of the vehicle.

4. The contactless power supply device as claimed in claim 1, wherein a trial power supply to supply the electric power through a minute electric power is carried out and, while the trial power supply is carried out, the estimation of the power transmission efficiency is carried out.

5. The contactless power supply device as claimed in claim 1, wherein, when a distance between the vehicle and the first coil becomes shorter than a predetermined distance, a trial power supply to supply electric power through a minute electric power is carried out and, while the trial power supply is carried out, the estimation of the power transmission efficiency is carried out.

6. A contactless power supply device for transmitting an electric power from a first coil to a second coil in a contactless manner by at least a magnetic coupling, comprising:

a power transmitting circuit including the first coil;

a sensor configured to measure a current flowing through the power transmitting circuit or to measure a voltage applied to the power transmitting circuit;

a battery providing a power source of a vehicle;

a charging circuit including the second coil and configured to charge the battery;

an informing device; and

a controller in communication with the sensor, the controller being configured to;

determine an input electric power of the power transmitting circuit from at least either one of values from a detected current or a detected voltage detected by the sensor;

estimate a power transmission efficiency from the first coil to the second coil on a basis of a correlation between the power transmission efficiency from the first coil to the second coil and the input electric power such that as the input electric power becomes higher, the estimated power transmission efficiency becomes higher;

determine that a positional deviation between the first coil and the second coil falls in a range in which the battery is chargeable, in a case where the power transmission efficiency estimated by the controller is higher than a predetermined value;

based on the determination that the positional deviation falls in the range in which the battery is chargeable, control the informing device to indicate that the charging is allowed; and

in response to the indication that the charging is allowed, enable a user of the vehicle to confirm via the informing device that the controller controls the charging circuit to charge the battery.