WO2012132205A1

WO2012132205A1 - Contactless power-reception device

Info

Publication number: WO2012132205A1
Application number: PCT/JP2012/001139
Authority: WO
Inventors: 宮下　功寛; 悟天利
Original assignee: パナソニック株式会社
Priority date: 2011-03-31
Filing date: 2012-02-21
Publication date: 2012-10-04
Also published as: JP2014123999A

Abstract

A contactless power-reception device (10) that is attached to the bottom of a vehicle (40) and receives power wirelessly from a contactless power-feed device (20) disposed below said contactless power-reception device. Said contactless power-reception device has: a power-reception coil (102) for receiving power wirelessly from the power-feed device (20); a wireless circuit board (206) and communication antenna (105) for performing short-range wireless communication with the power-feed device (20); a magnetic-field blocking member (104) comprising a conductor disposed on the vehicle side of the power-reception coil (102); a frame (50) that is made from a conductive material and attached to the top of the contactless power-reception device (10) and the bottom of the vehicle (40); and a magnetic-field suppression member (902) that prevents a loop current from flowing along an opening (L) formed by the contactless power-reception device (10) and the aforementioned frame (50), preventing a magnetic field from being formed thereby.

Description

Non-contact power receiving device

The present invention relates to a contactless power receiving apparatus in a contactless charging system for charging a secondary battery of an electric propulsion vehicle in a contactless manner, for example.

First, an example of a non-contact charging system will be described. In the non-contact charging system, in order to charge a battery installed in an electric propulsion vehicle represented by an electric vehicle or a plug-in hybrid vehicle, a non-contact power feeding device installed on the ground based on the mutual induction action of electromagnetic induction (Hereinafter referred to as “power feeding device”) transmits power in a non-contact manner to a non-contact power receiving device (hereinafter referred to as “power receiving device”) attached to the chassis of the electric propulsion vehicle.

In such a contactless charging system, when power is transmitted in a contactless manner, it is necessary to transmit information such as a charging instruction and required power between the power feeding device and the power receiving device. For this purpose, the power feeding device and the power receiving device include an antenna for short-range wireless communication (for example, see Patent Documents 1 and 2).

For example, the signal transmission coil communication device described in Patent Document 1 is used as a communication device of a non-contact charging system for electric propulsion vehicles. This non-contact charging system includes an antenna coil that is opposed to each other through a small gap space at the time of communication, and is formed in a symmetrical shape in a power feeding device and a power receiving device. The antenna coil has, for example, a substantially 8-character shape or a loop shape. Alternatively, the antenna coil is configured so that the antenna wires are orthogonal to each other on the plane of the planar magnetic body that is wound around the planar magnetic body and faces the power feeding device or the power receiving device. The antenna coil is disposed, for example, in a central space between the power transmission coil and the power reception coil.

JP 2008-288889 A JP 2006-345588 A

By the way, when the power receiving device is mounted on the electric propulsion vehicle, the wireless communication quality between the power feeding device and the power receiving device may be deteriorated depending on the mounting position and mounting method. It is necessary to mount the power receiving device on the electric propulsion vehicle in consideration of the wireless communication quality not deteriorating.

Therefore, an object of the present invention is to provide a non-contact power receiving apparatus that can suppress deterioration in wireless communication quality.

In order to achieve the above object, the present invention is configured as follows.

According to an aspect of the present invention, there is provided a non-contact power receiving device that is contactlessly supplied with power from a non-contact power feeding device that is attached to a lower portion of a vehicle and disposed below, and that is configured to receive power from the power feeding device without contact. A wireless circuit board and a communication antenna for short-distance wireless communication with the power feeding device, a magnetic field shielding member made of a conductor disposed on the vehicle side of the power receiving coil, A loop current is attached to the upper part of the contact power receiving device, attached to the lower part of the vehicle and made from a conductive material, and an opening formed by the non-contact power receiving device and the frame. There is provided a non-contact power receiving device having a magnetic field generation suppressing member that prevents and suppresses the generation of a magnetic field.

According to the present invention, even when the power receiving device is attached to the lower part of the vehicle via the metal frame and the power receiving device and the metal frame form an opening, the generation of the loop current flowing along the opening is prevented by the magnetic field generation suppressing member. Can be prevented. Thereby, generation | occurrence | production of the magnetic field which causes the deterioration of wireless communication quality is suppressed. As a result, the communication antenna of the power receiving apparatus can perform high-quality wireless communication.

These aspects and features of the present invention will become apparent from the following description taken in conjunction with the preferred embodiments with reference to the accompanying drawings. In this drawing,
Schematic diagram showing a non-contact charging system according to the present invention The figure which shows the inside of the electric power receiving apparatus and electric power feeding apparatus which are shown in FIG. Detailed view of the inside of the power receiving device of FIG. Detailed view of the inside of the power supply device of FIG. Detailed view of the metal frame shown in FIG. 1 is a schematic diagram showing an example of a wireless communication system mounted on the electric propulsion vehicle shown in FIG. Schematic diagram showing an example of a wireless communication system that performs in-vehicle-in-vehicle communication mounted on the electric propulsion vehicle shown in FIG. The figure which shows the magnetic field H which generate | occur | produces with the loop current I which flows along the opening formed by the power receiving apparatus and metal frame which are shown in FIG. 2, and a loop current The figure which shows the power receiving apparatus which concerns on Embodiment 1 of this invention The figure which shows the power receiving apparatus which concerns on embodiment of this invention

Figure 1 is a schematic diagram showing a non-contact charging system S according to the present invention. As shown in FIG. 1, the non-contact charging system S includes a non-contact power feeding device (hereinafter referred to as “power feeding device”) 20 and a non-contact power receiving device (hereinafter referred to as “power receiving device”) 10. ing. This non-contact charging system S is used, for example, for charging an electric propulsion vehicle (hereinafter referred to as “vehicle”) 40. In this case, the power receiving device 10 is mounted on the vehicle 40, and the power feeding device 20 is installed on the ground, for example. However, the power supply device 20 is not limited thereto, and may be configured to be buried in a parking space, for example, or to be movable below the vehicle 4.

FIG. 2 is a diagram schematically showing the inside of the power receiving device 10 and the power feeding device 20 shown in FIG. FIG. 2 illustrates a state where the power receiving device 10 and the power feeding device 20 are arranged to face each other, that is, a state in which power is supplied from the power feeding device 20 to the power receiving device 10 in a contactless manner.

FIG. 3 is a diagram showing details of the inside of the power receiving device 10 of FIG. 3A is a top view of the power receiving device 10, FIG. 3B is a side view of the power receiving device 10 viewed from the side of the vehicle 40, and FIG. 3C is a power receiving device 10 viewed from the rear of the vehicle 40. FIG. FIG. 4 is a diagram showing in detail the inside of the power feeding device 20 of FIG. 4A is a top view of the power feeding device 20, FIG. 4B is a side view of the power feeding device 20 viewed from the side of the vehicle 40, and FIG. It is the front view of the electric power feeder 20 seen from.

As shown in FIGS. 2 and 3, the power receiving device 10 includes a load circuit 101, a power receiving coil 102, a ferrite 103, a magnetic field shielding member 104 made of a conductor, a first communication antenna 105, and a first communication antenna 105. Wireless circuit board 106 and a first antenna feed line 107.

The power receiving coil 102 generates electric power by receiving a magnetic field generated by a power transmission coil 108 of the power feeding device 20 described later, that is, receives power from the power feeding device 20 in a non-contact manner. The load circuit 101 includes a rechargeable battery that is charged with power generated by the power receiving coil 102, a rectifier circuit that supplies the power generated by the power receiving coil 102 to the rechargeable battery, and the like.

The ferrite 103 and the magnetic shielding member 104 are disposed on the vehicle side of the power receiving coil 102. As a result, a magnetic field generated by a power transmission coil 108 of the power supply device 20 described later is prevented from spreading to the vehicle side of the power reception coil 102.

As shown in FIG. 4, the power feeding device 20 includes a power transmission coil 108, a metal base 109, a second communication antenna 110, a second wireless circuit board 111, a second antenna power supply line 112, A high-frequency power source 113.

The high frequency power supply 113 outputs high frequency power to the power transmission coil 108. The power transmission coil 108 is connected to a high frequency power supply 113, and generates a high frequency magnetic field when high frequency power is supplied from the high frequency power supply 113.

The first communication antenna 105 of the power receiving apparatus 10 and the second communication antenna 110 of the power supply apparatus 20 exchange signals (perform short-range wireless communication). For example, a signal for detecting misalignment between the power transmission coil 108 and the power reception coil 102 or a signal for synchronizing control of the power feeding device 20 and the power reception device 10 is the first communication antenna 105 and the second communication. The data is exchanged with the antenna 110 for use.

The first communication antenna 105 is a loop antenna that transmits a magnetic field corresponding to a signal. The first communication antenna 105 is also disposed in the vicinity of the power receiving coil 102 and is electrically connected to the first wireless circuit board 106 via the first antenna feed line 107. On the other hand, the second communication antenna 110 is a loop antenna that receives the magnetic field generated by the first communication antenna 105. The second communication antenna 110 is also disposed in the vicinity of the power transmission coil 108 and is electrically connected to the second radio circuit board 111 via the second antenna feed line 112.

Note that the first communication antenna 105 may receive a magnetic field, and the second antenna 110 may transmit the magnetic field.

Further, the first communication antenna 105 and the second communication antenna 110 are not limited to a loop shape, and may be a linear shape or a plate shape.

As shown in FIG. 2, the power receiving device 10 is mounted (attached) to the lower portion of the vehicle 40 via the metal frame 30. FIG. 5 is a detailed view of the metal frame 30. 5A is a top view of the metal frame 30, FIG. 5B is a side view of the metal frame 30 viewed from the side of the vehicle 40, and FIG. It is the front view of the metal frame 30 seen from.

The metal frame 30 is for absorbing an impact applied to the power receiving device 10 due to a rear-end collision with a moving body that has moved from the rear of the vehicle 40, or a collision with a stone or a wheel stop during traveling or parking.

Further, as shown in FIG. 2, the metal frame 30 is for attaching the power receiving device 10 to the lower part of the vehicle 40. The metal frame 30 is attached to the upper part (magnetic field shielding member 104) of the power receiving device 10 and is attached to the lower part of the vehicle 40. In order to facilitate the work of mounting the power receiving device 10 on the vehicle 40, the power receiving device 10 and the metal frame 30 are preferably integrated.

As shown in FIG. 5, the metal frame 30 has a frame shape and is composed of four square bars 401 (a) to 401 (d). A square bar 401 (b) extending in the width direction of the vehicle 40 is connected between the ends of the square bars 401 (c) and 401 (d) extending in parallel to the front-rear direction of the vehicle 40 on the front side of the vehicle 40. Yes. The square bar 401 (a) is connected to the lower part of the rear side end of the vehicle 40 of the square bars 401 (c) and 401 (d). The square bars 401 (c) and 401 (d) have through-holes 402 (a) through which connecting members 114 (a) to 114 (d) (see FIG. 2) for connecting the power receiving apparatus 10 and the vehicle 40 pass. ) To 402 (d) are formed. The through holes 402 (a) to 402 (d) preferably have long hole cross sections so that the power receiving device 10 can be attached to different types of vehicles 40.

Further, as shown in FIG. 1, since the vehicle 40 travels with the power receiving device 10 suspended, the metal frame 30 needs to have strength that can withstand this. Therefore, the metal frame 30 is made of a metal material such as aluminum or iron. Furthermore, the metal frame 30 mounted on the vehicle 40 is preferably as light as possible. For example, the square bars 401 (a) to 401 (d) of the metal frame 30 are made hollow and connected to each other by welding or screws. Further, the square bars 401 (a) to 401 (d) may be connected so that the internal spaces of the square bars 401 (a) to 401 (d) are communicated with each other.

Further, as shown in FIG. 2, a third communication antenna 115 is mounted on the vehicle to which the power receiving device 10 is attached. The third communication antenna 115 is connected to the third radio circuit board 116 via the third antenna feed line 117 and is arranged on the inner side or the outer side of the vehicle 40. The third antenna 115 communicates with an external fourth communication antenna 501 as shown in FIG. The fourth communication antenna 501 is connected to the fourth circuit board 502 via the fourth antenna feed line 503. In this case, the third antenna 115 is, for example, a transmission antenna for a smart entry system or a reception antenna for a terrestrial digital TV.

Further, as shown in FIG. 7, the third communication antenna 115 communicates with the fifth communication antenna 601 in the vehicle. The fifth communication antenna 601 is connected to the fifth circuit board 602 via the fifth antenna feed line 603. In this case, the third antenna 115 in FIG. 7 is, for example, an antenna for Bluetooth (registered trademark) or a wireless LAN (Local Area Network) of a short-range wireless system.

According to such a configuration, the signal (current) output from the first wireless circuit board 106 flows to the loop-shaped first communication antenna 105 made of a conductor. A magnetic field is generated by the current flowing in the loop portion. The generated magnetic field is received by the second communication antenna 110. At this time, a part of the magnetic field induces the magnetic shielding member 104, and a current flows through the magnetic shielding member 104.

As shown in FIG. 1, since the magnetic field shielding member 104 made of a conductor is in contact with the metal frame 30, that is, electrically connected, the current induced in the magnetic field shielding member 104 is applied to the metal frame 30. It flows toward. Then, as shown in FIG. 8, it flows loop current I generates a magnetic field H is. The loop current I flows along the opening L formed by the power receiving device 10 and the metal frame 30. Specifically, the opening L is formed by a part of the square bar 401 (a), a part of the square bar 401 (c), a part of the square bar 401 (d), and the magnetic field shielding member 104 of the power receiving device 10. Is done.

As shown in FIG. 8, when a loop current I flows along the opening L and a magnetic field H is generated along with this, the wireless communication quality between the first communication antenna 105 and the second communication antenna 110 is reduced. descend. In addition, due to the magnetic field H, the quality of wireless communication between the third communication antenna 115 and the fourth communication antenna 501 (or the fifth communication antenna 601) also deteriorates. When the frequency of the magnetic field H generated by the loop current I is substantially the same as the frequency used in wireless communication, the magnetic field distribution changes between the antennas due to the magnetic field H, which affects the reception level of the antenna. As a result, the wireless communication quality is degraded. On the other hand, when the frequency of the magnetic field H and the radio communication frequency are far from each other, the reception sensitivity of the receiver of the radio circuit board is lowered, and the radio communication quality is lowered.

(Embodiment 1)
In order to suppress deterioration in wireless communication quality caused by a magnetic field generated by a loop current flowing along an opening formed by the power receiving device and the metal frame, the power receiving device of the first embodiment is configured to generate a magnetic field. It has a suppression member. The power receiving device according to the first embodiment is the same as the power receiving device 10 described so far, except for the metal frame. Therefore, the metal frame of the power receiving device according to the first embodiment will be mainly described.

As shown in FIG. 9, the metal frame 50 of the power receiving device according to the first embodiment is almost the same as the metal frame 30 shown in FIG. Further, the metal frame 50 according to the first embodiment forms an opening L between the power receiving device 10 and the metal frame 30 shown in FIG. However, in the metal frame 50 of the first embodiment, a part of the portion of the metal frame 50 that forms the opening L is configured by the magnetic field generation suppressing member 902.

Specifically, a part of the portion of the square bar 901 of the metal frame 50 that forms the opening L is composed of a magnetic field generation suppressing member 902. The magnetic field generation suppressing member 902 is made of a nonconductive material. Specifically, the magnetic field generation suppressing member 902 electrically connects the part of the square bar 901 that is electrically connected to the power receiving apparatus 10 and the part of the square bar 901 that is electrically connected to the square bar 401 (a). They are connected in an insulated state. Such a magnetic field generation suppressing member 902 prevents current from flowing along the opening L (generation of the loop current I is prevented). Thereby, generation | occurrence | production of the magnetic field which causes the deterioration of wireless communication quality is suppressed. As a result, the first communication antenna 105 and the second communication antenna 110 can perform high-quality short-range wireless communication.

(Embodiment 2)
Similarly to the power receiving device according to the first embodiment, the power receiving device according to the second embodiment also includes a magnetic field generation suppressing member. However, the form of the magnetic field generation suppressing member of the second embodiment is different from the magnetic field generation member 902 of the first embodiment. Further, the power receiving device of the second embodiment is the same as the power receiving device 10 described so far.

FIG. 10 shows the metal frame member 60 of the second embodiment. The magnetic field generation suppressing member 1001 according to the second embodiment is a member that closes the opening L formed by the metal frame 60 and the power receiving device 10. Specifically, the magnetic field generation suppressing member 1001 is made of a conductive material, and there is no gap between the square bars 401 (a), 401 (c), and 401 (d) of the metal frame 60 and the charging device 10. , Configured to contact these. Such a magnetic field generation suppressing member 902 prevents current from flowing along the opening L (generation of the loop current I is prevented). Thereby, generation | occurrence | production of the magnetic field which causes the deterioration of wireless communication quality is suppressed. As a result, the first communication antenna 105 and the second communication antenna 110 can perform high-quality short-range wireless communication.

Although the present invention has been described with reference to two embodiments, the present invention is not limited to these embodiments. For example, the metal frame for attaching the power receiving device to the lower part of the vehicle may be a resin frame made of a conductive resin material. That is, according to the present invention, the frame for attaching the power receiving device to the vehicle may be conductive.

Although the present invention has been fully described in connection with preferred embodiments with reference to the accompanying drawings, various changes and modifications will be apparent to those skilled in the art. Such changes and modifications are to be understood as being included therein, so long as they do not depart from the scope of the present invention according to the appended claims.

The disclosures of the specification, drawings, and claims of Japanese Patent Application No. 2011-077629 filed on March 31, 2011 are incorporated herein by reference in their entirety. .

The contactless power receiving device according to the present invention is suitable for charging an electric propulsion vehicle that requires high-quality wireless communication.

DESCRIPTION OF SYMBOLS S Contactless charging system 10 Power receiving apparatus 102 Power receiving coil 103 Ferrite 104 Magnetic field shielding member 105 First communication antenna 106 First radio circuit board 107 First antenna feeder 20 Power feeder 40 Electric propulsion vehicle 30 Frame

Claims

A non-contact power receiving device that is attached to the lower part of the vehicle and receives power from the non-contact power feeding device disposed below,
A power receiving coil for receiving power from the power feeding device in a contactless manner;
A radio circuit board and a communication antenna for performing near field communication with the power supply device;
A magnetic field shielding member made of a conductor disposed on the vehicle side of the power receiving coil;
A frame attached to an upper portion of the non-contact power receiving device, attached to a lower portion of the vehicle, and made of a conductive material;
A non-contact power receiving apparatus comprising: a magnetic field generation suppressing member that suppresses generation of a magnetic field by preventing a loop current from flowing along an opening formed by the non-contact power receiving apparatus and the frame.
The non-contact power receiving device according to claim 1, wherein the magnetic field generation suppressing member is made of a non-conductive material and constitutes a part of the portion of the frame that forms the opening to prevent the generation of the loop current. .
The non-contact power receiving device according to claim 1, wherein the magnetic field generation suppressing member is made of a conductive material and blocks the opening to suppress generation of the loop current.
The non-contact power receiving device according to any one of claims 1 to 3, wherein the frame is a metal frame made of a metal material.