Temperature estimation device and temperature estimation method for contactless power-reception device

• US 10,180,361 B2
• Filed: 04/07/2015
• Issued: 01/15/2019
• Est. Priority Date: 04/07/2015
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Ozaki, Michio
• Primary Examiner(s): Jagan, Mirellys
• Application Number:
  US15/564,283
• Publication Number:
  US 20180136048A1
• Time in Patent Office: 1,379 Days
• Field of Search: 374152, 374141
• CPC Class Codes: B60L 2240/36 Temperature of vehicle components or parts
• CPC Class Codes: B60L 2260/44 by parameter estimation
• CPC Class Codes: B60L 3/00 Electric devices on electrically-propelled vehicles for safety purposes; Monitoring operating variables, e.g. speed, deceleration or energy consumption methods or circuit arrangements for monitoring or controlling batteries or fuel cells B60L58/00
• CPC Class Codes: B60L 50/30 using propulsion power stored mechanically, e.g. in fly-wheels
• CPC Class Codes: B60L 53/12 Inductive energy transfer
• CPC Class Codes: B60L 53/36 by positioning the vehicle
• CPC Class Codes: B60L 53/38 specially adapted for charging by inductive energy transfer
• CPC Class Codes: G01K 1/14 Supports; Fastening devices; Arrangements for mounting thermometers in particular locations
• CPC Class Codes: G01K 3/005 Circuits arrangements for indicating a predetermined temperature fire detection G08B17/00
• CPC Class Codes: G01K 3/10 in respect of time, e.g. reacting only to a quick change of temperature
• CPC Class Codes: G01R 21/00 Arrangements for measuring electric power or power factor G01R7/12 takes precedence
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• 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 50/12 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 7/00309 Overheat or overtemperature protection
• 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
• CPC Class Codes: Y02T 90/16 : Information or communication technologies improving the operation of electric vehicles

Abstract

A charging controller (25) acquires the power loss of a power transmission coil (31) from a power supply device (100) via wireless communication. A temperature estimation unit (33) estimates the ambient temperature of a power reception coil on the basis of a preset amount of heat generation of a power reception device (200) and the power loss of the power transmission coil (31). In this case, when the positional relationship between the power transmission coil (31) and the power reception coil (41) is shifted from a normal positional relationship, the temperature estimation unit (33) increases, in accordance with the magnitude of positional shift amount, the contribution to a temperature rise due to the power loss of the power transmission coil (31). Accordingly, an abnormal increase in the ambient temperature of the power reception coil (41) can be prevented.

Claims

1. A temperature estimation device for estimating an ambient temperature of a power reception coil which contactlessly receives a power transmitted from a power transmission coil, the temperature estimation device comprising:

a power transmission-side power loss acquisition unit which acquires a power loss of the power transmission coil;

a positional shift amount acquisition unit which acquires

a gap between the power transmission coil and the power reception coil and

a planar positional shift amount between the power transmission coil and the power reception coil, and

determines a correction coefficient on a basis of the gap and the planar positional shift amount; and

a temperature estimation unit which estimates the ambient temperature of the power reception coil on a basis of a preset amount of heat generation of the power reception device and the power loss of the power transmission coil, wherein

when a positional relationship between the power transmission coil and the power reception coil is shifted from a normal positional relationship, the temperature estimation unit changes, a magnitude of influence of the power loss to a rising amount of the estimated ambient temperature, by multiplying the power loss of the power transmission coil by the correction coefficient.

2. The temperature estimation device according to claim 1, further comprising:

a coupling coefficient acquisition unit which acquires a coupling coefficient between the power transmission coil and the power reception coil, wherein

the positional shift amount acquisition unit acquires the gap on a basis of the planar positional shift amount and the coupling coefficient.

3. The temperature estimation device according to claim 1, wherein

the positional shift amount acquisition unit acquires a positional shift amount in an X-axis direction and a positional shift amount in a Y-axis direction perpendicular to the X-axis, as the planar positional shift amount, and further calculates the correction coefficient by a formula:

C=(a*Lx+b*Ly+c)/G²

where a, b, and c are coefficients, G is the gap between the power transmission coil and the power reception coil, and Lx, Ly are the positional shift amount in the X-axis direction and the positional shift amount in the Y-axis direction, respectively.

4. A temperature estimation method for estimating an ambient temperature of a power reception coil which contactlessly receives a power transmitted from a power transmission coil, the temperature estimation method comprising the steps of:

acquiring a power loss of the power transmission coil;

acquiring

a gap between the power transmission coil and the power reception coil and

a planar positional shift amount between the power transmission coil and the power reception coil, and

determining a correction coefficient on a basis of the gap and the planar positional shift amount;

estimating the ambient temperature of the power reception coil on a basis of a preset amount of heat generation of the power reception device and the power loss of the power transmission coil; and

changing a magnitude of influence of the power loss to a rising amount of the estimated ambient temperature by multiplying the power loss of the power transmission coil by the correction coefficient, in a case where a positional relationship between the power transmission coil and the power reception coil is shifted from a normal positional relationship.