Wireless power supply system

• US 10,195,951 B2
• Filed: 04/09/2015
• Issued: 02/05/2019
• Est. Priority Date: 04/09/2015
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Maikawa, Kengo
• Primary Examiner(s): Barnie, Rexford
• Assistant Examiner(s): Willoughby, Terrence
• Application Number:
  US15/564,840
• Publication Number:
  US 20180105049A1
• Time in Patent Office: 1,398 Days
• CPC Class Codes: B60L 50/60 using power supplied by batteries in combination with fuel cells B60L50/75
• 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 53/31 Charging columns specially adapted for electric vehicles
• CPC Class Codes: B60L 53/37 using optical position determination, e.g. using cameras
• CPC Class Codes: B60L 53/38 specially adapted for charging by inductive energy transfer
• CPC Class Codes: B60M 7/00 Power lines or rails specially adapted for electrically-propelled vehicles of special types, e.g. suspension tramway, ropeway, underground railway
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• 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 supply system of the present invention performs wireless power supply between a power transmission coil installed at a parking space and a power reception coil mounted on a vehicle, transmits judging power for judging a parking position from the power transmission coil to the power reception coil in an operation of parking the vehicle in the parking space, and sets an excitation frequency of the judging power to a frequency lower than an in-phase resonance point or higher than an anti-phase resonance point.

Claims

1. A wireless power supply system that performs wireless power supply between a power transmission system installed at a parking space and a power reception system mounted on a vehicle, the wireless power supply system comprising:

a power transmission coil; and

a controller configured to;

set an excitation frequency of judging power to a first frequency lower than a predetermined in-phase resonance point or higher than a predetermined anti-phase resonance point, wherein at the first frequency, a transimpedance representing a ratio of a received power voltage of a power reception coil to an excitation current of the power transmission coil is equal to or higher than a predetermined value; and

generate an excitation voltage command to cause the power transmission coil to transmit the judging power whose excitation frequency is set to the first frequency for judging a parking position from the power transmission coil to the power reception coil in an operation of parking the vehicle in the parking space,

wherein the predetermined in-phase resonance point is a frequency at which a magnetic flux generated at the power transmission coil and a magnetic flux generated at a power reception coil resonate with each other while strengthening each other, and the predetermined anti-phase resonance point is a frequency at which a magnetic flux generated at the power transmission coil and a magnetic flux generated at the power reception coil resonate with each other while cancelling out each other.

2. The wireless power supply system according to claim 1, wherein the received power voltage of the power reception coil is set within a range higher than a minimum resolution of a voltage detector that detects the received power voltage of the power reception coil.

3. The wireless power supply system according to claim 1, wherein the excitation current of the power transmission coil is set within a range in which a surface leakage magnetic flux density of the power transmission coil is equal to or lower than a standard value set for the power transmission coil.