JP5384195B2 - Non-contact power supply device - Google Patents

Description

The present invention relates to a contactless power supply device that supplies power to a load (for example, a battery, a light bulb, a power supply of a mechanical device, etc.) of a mobile vehicle in a contactless manner.

For example, a vehicle powered by a battery in a factory, etc., needs to be charged regularly. Stop the vehicle near the charger at a predetermined place and connect the battery of the vehicle and the charger using a connection cord. The battery was being charged. However, when charging a battery using a connection cord, it is extremely troublesome to connect the connection cord to a power supply source. For example, as shown in Patent Documents 1 to 3, power is supplied to the vehicle without contact. To be done. In Patent Documents 1 to 3, a primary coil connected to a high-frequency power source and a secondary coil connected to a load are provided, and L (reactor) and C (capacity) are provided on the primary coil side or the secondary coil side. A resonant circuit is provided.

Japanese Patent Laid-Open No. 2005-94862 JP 2006-325350 A WO2006 / 022365 JP-A-63-73837

However, as described in Patent Documents 1 to 3, when a resonance circuit is incorporated on the primary coil side or the secondary coil side, there is a problem that it is difficult to obtain a large load current. Although the reason for this is not clear, it is presumed that the circuit queue (Q) is lowered because a load is connected to the circuit.

On the other hand, FIG. 7 of Patent Document 4 proposes a power supply device that uses a saturable iron core and includes a secondary coil that connects a load and a tertiary coil that uses a capacitor for resonance (capacitor) as a load. The capacitor circuit and the secondary coil are described as being electrically insulated.
Therefore, the present inventor provides a tertiary coil in addition to the secondary coil, and incorporates a resonance circuit in the tertiary coil, that is, when a predetermined amount of capacitor is connected in parallel and arranged near the secondary coil, It was confirmed that the load current can be sufficiently passed through the secondary coil, but even if the secondary coil and the tertiary coil are arranged in an insulated state, when the secondary coil and the tertiary coil are wound on the same core, Since a large-capacity resonance current (for example, more than 100 A) flows through the tertiary coil, there is a problem that the secondary coil is excessively heated and the frequency of the high-frequency power source needs to be shifted considerably from the resonance frequency. understood. If the resonance frequency is shifted, there arises a problem that the power propagation efficiency from the primary coil to the secondary coil decreases.

Then, although the secondary coil and the tertiary coil were separated and the trial production of the non-contact power supply device was made, when the primary coil, the secondary coil, and the tertiary coil are arranged in this order, the secondary coil is also excessive (for example, 200 ° C. If the frequency of the high-frequency power source is not shifted from the resonance frequency, the practical application is difficult. However, if the primary coil, the tertiary coil, and the secondary coil are arranged in this order, the reason is not clear, but even if the frequency of the high-frequency power source is adjusted to the resonance frequency or a value close thereto, the heat generation of the secondary coil can be suppressed to some extent. I found out.

The present invention has been made in view of such circumstances, and devised the configuration and arrangement of a tertiary coil connected to a resonance capacitor and a secondary coil that generates power to be supplied to a load, and a power feeding unit and a power receiving unit. It is an object of the present invention to provide a non-contact power supply apparatus that is capable of obtaining a larger current as a secondary current by separating the distance.

A non-contact power supply apparatus according to a first invention that meets the above-mentioned object is mounted on a moving vehicle, including a power feeding unit that is arranged in a fixed state and is connected to a high-frequency power source. When located at a position or in a predetermined region, the power feeding unit is opposed to each other with a gap, and has a secondary coil and a tertiary coil that are magnetically coupled to the primary coil, and supplies power to the load to the secondary coil. A non-contact power supply device including a power reception unit to which a resonance capacitor is connected to the tertiary coil,
The secondary coil and the tertiary coil are separately disposed, and the tertiary coil is disposed closer to the front side of the secondary coil than the secondary coil ,
The primary coil has an air core and a spiral flat surface, and a magnetic shield plate made of a ferrite core covering the primary coil from the back is disposed on the back of the primary coil, and the tertiary coil and the secondary coil Is wound around the central magnetic pole part of the E-shaped core formed using a ferrite core,
Furthermore, the primary coil, the tertiary coil disposed at a distance L from the primary coil, the secondary coil disposed immediately after the tertiary coil, and the resonance capacitor are formed. When the resonance frequency of the resonance circuit is matched with the frequency of the high-frequency power source, and the primary coil and the tertiary coil are closer than the distance L, the resonance frequency of the resonance circuit is shifted from the frequency of the high-frequency power source and the load current is reduced. Ru is reduced.

A contactless power supply apparatus according to the second invention, in the contactless power supply device according to the first invention, the distance L is in the range of 15 to 50 mm.

And the non-contact electric power supply apparatus which concerns on 3rd invention is the non-contact electric power supply apparatus which concerns on the 1st , 2nd invention. WHEREIN: The said load is a battery used as the power supply of the said mobile vehicle. In this case, as a matter of course, the secondary coil is provided with a battery charging circuit including a rectifier circuit.

In the non-contact power supply device according to claims 1 to 3 , since the secondary coil and the tertiary coil are separately arranged, heat conduction from the tertiary coil through which a large current flows is reduced, and the tertiary coil Is arranged on the front side closer to the primary coil than the secondary coil, the secondary coil is not heated excessively. This is obvious from the experimental results. 1) The magnetic flux generated by the tertiary coil is larger on the primary coil side to which power is supplied, and 2) the tertiary coil is connected to the secondary coil side. If it arrange | positions at a rear side, it will be understood that a secondary coil is induction-heated by the magnetic flux (mainly leakage magnetic flux) of a tertiary coil.

In particular, a resonance circuit formed by including a primary coil, a tertiary coil disposed at a distance L from the primary coil, a secondary coil disposed immediately after the tertiary coil, and a resonance capacitor. When the resonance frequency is matched with the frequency of the high frequency power supply and the primary coil and the tertiary coil are closer than the distance L, the resonance frequency of the resonance circuit is shifted from the frequency of the high frequency power supply. Even if it is too much, excessive electric power is not supplied to the power receiving unit, and therefore it can be operated safely.

In the non-contact power supply device according to claim 2 , the distance L is in the range of 15 to 50 mm. Thereby, power transmission from the power feeding unit to the power receiving unit can be performed efficiently.

Further, in the non-contact power supply device according to any one of claims 1 to 3 , the primary coil is a magnetic shield comprising a ferrite core covering the primary coil from the back portion on the back portion of the primary coil, the winding having an air core and a spiral plane shape. Since the plate is arranged, the magnetic shield material serves as a core, and the apparatus can be prevented from being induction heated by the magnetic flux generated at the back. Further, since the tertiary coil and the secondary coil are separately wound around the central magnetic pole portion of the E-shaped core formed using the ferrite core, the magnetic efficiency is increased and the tertiary coil is generated by the tertiary coil constituting the resonance circuit. A large magnetic flux can be prevented from leaking outside.
Further, since the primary coil has an air core and a spiral plane, the power feeding portion can be formed thin.

In the non-contact power supply apparatus according to the third aspect , since the load is a battery serving as a power source for the moving vehicle, the battery of the moving vehicle can be charged with the power receiving unit and the power feeding unit in a non-contact state.

It is explanatory drawing of the non-contact electric power supply apparatus which concerns on one embodiment of this invention. (A), (B) is the front view and sectional drawing which show schematic structure of the primary coil used for the non-contact electric power supply apparatus. (A), (B) is the front view and sectional drawing which show schematic structure of the principal part of the power receiving part used for the non-contact electric power supply apparatus. It is a graph for demonstrating operation | movement of the non-contact electric power supply apparatus of this invention. It is explanatory drawing of the non-contact electric power supply apparatus which concerns on other embodiment of this invention.

Next, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.
As shown in FIGS. 1 to 3, the non-contact power supply device 10 according to one embodiment of the present invention is provided in a power supply unit 11 disposed on a side wall, a floor portion, or a ceiling portion, and a mobile vehicle 12. And a power receiving unit 13. These will be described in detail below.

A primary coil 14 wound in a spiral plane with an air core is disposed in a fixed state in the power supply unit 11, and a high-frequency power source 15 is connected to the primary coil 14. The high-frequency power supply 15 includes a rectifier circuit of an AC power supply and an inverter circuit that converts a direct current from the rectifier circuit to a high frequency of 20 kHz to 100 kHz (in this embodiment, 20 kHz to 30 kHz).

As shown in FIG. 3, the power receiving unit 13 includes a secondary coil 17 and a tertiary coil 18 that are arranged in a separated state, and the secondary coil 17 and the tertiary coil 18 are each a central magnetic pole of the E-shaped core 20. It is wound around part 21. The number of turns of the tertiary coil 18 is 12, and the number of turns of the secondary coil 17 is 2 times plus 2 times, for a total of 4 times, and the middle point is output. In FIG. 3A, reference numerals 22 and 23 are connection lead wires for the tertiary coil 18, and reference numerals 24-27 are connection lead wires for the secondary coil 17 that is wound twice. In addition, when the moving vehicle 12 is in a predetermined position or a predetermined region, the power receiving unit 13 is disposed so as to face the power feeding unit 11 with a gap, and the secondary coil 17 and the tertiary coil 18 are magnetically coupled to the primary coil 14. .

The E-shaped core 20 is formed by superposing four E-shaped ferrite core plates formed in an E shape in plan view, and has end-side magnetic pole portions 28 and 29 on both sides of the central magnetic pole portion 21. As a whole, it has a cross-sectional area that is not saturated by the passing magnetic flux. A secondary coil 17 is disposed on the back side of the E-shaped core 20 and a tertiary coil 18 is disposed on the near side. That is, the tertiary coil 18 is disposed closer to the primary coil 14 than the secondary coil 17. Although the secondary coil 17 and the tertiary coil 18 can be sealed with resin, in this embodiment, the resin is not sealed in order to maintain an air-cooled environment.

On the other hand, the power feeding unit 11 has a primary coil 14 connected to a high frequency power supply 15. As shown in FIGS. 2 (A) and 2 (B), the primary coil 14 has a square shape (which may be circular or elliptical) with rounded corners in the air center, and 8 copper wires in a spiral plane shape. It is composed of 10 to 10 turns. The vertical and horizontal dimensions of the primary coil 14 are the same as the vertical and horizontal dimensions of the tertiary coil 18 (the secondary coil 17 is the same in this embodiment). In FIG. 2, reference numerals 31 and 32 denote connection leads.

A shield plate (magnetic shield plate) 33 made of a ferrite core having good high-frequency magnetic properties is disposed on the back of the flat primary coil 14. The dimensions of the shield plate 33 in plan view are the same as or slightly wider than the vertical dimension a and the horizontal dimension b of the E-shaped core 20 as viewed from the front as shown in FIG. The thickness of the shield plate 33 has a cross-sectional area that does not saturate with the generated magnetic flux.

As shown in FIG. 1, a resonance capacitor 35 is connected to the tertiary coil 18. This capacitor 35 has a sufficiently small internal resistance (ie, a small tan δ) when using a high frequency, and is constituted by connecting a plurality of capacitors in parallel. On the other hand, a charging circuit 36 including a rectifier circuit is connected to the secondary coil 17 to supply DC power to a battery (battery) 37 that is a load. The moving vehicle 12 is provided with a motor and a control device using the battery 37 as a power source to drive the wheels.

In this non-contact power supply device 10, the resonance frequency f of the resonance circuit Z formed by the inductance (that is, the primary coil 14, the secondary coil 17, the tertiary coil 18) and the capacitor 35 viewed from the high-frequency power supply 15 side is: When the power feeding unit 11 and the power receiving unit 12 are arranged at a distance L, that is, the primary coil 14 and the tertiary coil 18 are arranged at a distance L (in this embodiment, 15 to 50 mm, more preferably 15 to 25 mm), The value of the capacitor 35 is determined so as to match the oscillation frequency of the high frequency power supply 15.

As a result, when the distance between the power feeding unit 11 and the power receiving unit 12 becomes smaller than L and approaches 0 mm, the resonance frequency f of the resonance circuit Z increases and deviates from the oscillation frequency of the high frequency power supply 15. On the other hand, when the distance between the power feeding unit 11 and the power receiving unit 12 is reduced, the coupling between the primary coil 14 and the secondary coil 17 becomes dense, and in the case of the same load, the current increases, but the resonance frequency f of the resonance circuit Z is As a result, the load current decreases as the distance from the distance L decreases, as shown in FIG.

In addition, when the resonant circuit which directly connected the capacitor | condenser 35 to the tertiary coil 18 is formed like this invention, it is thought that Q of a resonant circuit becomes large, the load current at the time of resonance becomes large, and it remove | deviates from a resonant state. It has been confirmed that the load current becomes small. On the other hand, when the tertiary coil is not provided and a load is connected to the resonance circuit, the Q of the resonance circuit becomes small, and the increase / decrease in current due to the difference in distance between the power feeding unit and the power receiving unit is small. It is considered that the effect shown in is not remarkable.

Further, the resonance frequency f of the resonance circuit Z is formed by the number of turns, the shape, the interval between the primary coil 14, the secondary coil 17 and the tertiary coil 18, and the value of the capacitor 35. Accordingly, the primary coil 14, the secondary coil 17, and the tertiary coil 18 are set in advance, and after the distance (interval) L between the power feeding unit 11 and the power receiving unit 13 is set to a predetermined value, the oscillation frequency of the high frequency power source is adjusted. Therefore, it is preferable to match the oscillation frequency of the high frequency power supply 15 with the resonance frequency f of the resonance circuit Z.
When an experiment is performed using this non-contact power supply device 10, the power supply unit 11 and the power receiving unit 13 are separated from each other, and the storage battery 37 can be charged with the supplied AC power supply voltage of 200 V and 10 A, and the output of 50 V and 20 A. It was.

In the above embodiment, the E-type core is used for the power receiving unit, and the secondary coil and the tertiary coil are separately wound around the central magnetic pole unit. However, as shown in FIG. The coil 41 and the tertiary coil 42 are spiral and flat in the air core. The power receiving unit 46 has a tertiary coil 42 on the side close to the primary coil 40, a secondary coil 41 immediately thereafter, and a ferrite immediately after the secondary coil 41. A shield plate 43 made of a core can also be disposed. In this case, a shield plate 44 made of a ferrite core is also arranged on the back of the primary coil 40. The shape of the primary coil 40, the secondary coil 41, and the tertiary coil 42 in a plan view may be a circle, a rectangle (including a case where a corner is rounded), an ellipse, or the like.

Further, the shield plate 43 is larger than the secondary coil 41 and the shield plate 44 is larger than the primary coil 40 to prevent heating of the equipment at the back, and the magnetic paths of the coils 40 and 41 are further reduced. The resistance is reduced. The frequency adjustment of the high frequency power supply 15 and the configuration of the charging circuit 36 and the battery 37 are the same as those of the non-contact power supply apparatus 10. In FIG. 5, 45 indicates a power supply unit, and L indicates a distance (distance) between the power supply unit 45 and the power reception unit 46.

The present invention is not limited to the embodiment described above, and the shape, dimensions, number of turns, and the like can be changed without departing from the scope of the present invention.
The moving vehicle includes an automobile.
Furthermore, the winding shape of the primary coil, the secondary coil, and the tertiary coil that are separately arranged is arbitrary, and in addition to the case of winding in a plane spiral shape, some or all of these coils, regardless of whether they are centered or uncentered The present invention is also applied to a case where the tube is wound in a cylindrical state or an overlapped state in a separated state.

10: Non-contact power supply device, 11: Power feeding unit, 12: Mobile vehicle, 13: Power receiving unit, 14: Primary coil, 15: High frequency power source, 17: Secondary coil, 18: Tertiary coil, 20: E-shaped core, 21: Central magnetic pole part, 22-27: Connection lead wire, 28, 29: End side magnetic pole part, 31, 32: Connection lead wire, 33: Shield plate, 35: Capacitor, 36: Charging circuit, 37: Battery 40: primary coil, 41: secondary coil, 42: tertiary coil, 43, 44: shield plate, 45: power feeding unit, 46: power receiving unit

Claims (3)

A power supply unit provided with a primary coil that is arranged in a fixed state and connected to a high-frequency power supply, and when the mobile vehicle is located at a predetermined position or a predetermined region, the power supply unit has a gap. Power receiving unit having a secondary coil and a tertiary coil magnetically coupled to the primary coil, generating electric power to be supplied to a load to the secondary coil, and a resonance capacitor connected to the tertiary coil A contactless power supply device comprising:
The secondary coil and the tertiary coil are separately disposed, and the tertiary coil is disposed closer to the front side of the secondary coil than the secondary coil ,
The primary coil has an air core and a spiral flat surface, and a magnetic shield plate made of a ferrite core covering the primary coil from the back is disposed on the back of the primary coil, and the tertiary coil and the secondary coil Is wound around the central magnetic pole part of the E-shaped core formed using a ferrite core,
Furthermore, the primary coil, the tertiary coil disposed at a distance L from the primary coil, the secondary coil disposed immediately after the tertiary coil, and the resonance capacitor are formed. When the resonance frequency of the resonance circuit is matched with the frequency of the high-frequency power source, and the primary coil and the tertiary coil are closer than the distance L, the resonance frequency of the resonance circuit is shifted from the frequency of the high-frequency power source and the load current is reduced. A non-contact power supply device characterized by being reduced . 2. The non-contact power supply apparatus according to claim 1 , wherein the distance L is in a range of 15 to 50 mm. 3. The contactless power supply apparatus according to claim 1 or 2 , wherein the load is a battery serving as a power source for the mobile vehicle.

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