JP5562804B2 - Non-contact power feeding device with variable inductance - Google Patents

Description

  The present invention relates to a non-contact power feeding device. That is, the present invention relates to a variable inductance non-contact power feeding device that supplies power in a non-contact manner with an air gap from the ground side and primary side to the vehicle side and secondary side.

《Technical background》
A non-contact power supply device that supplies electric power from the outside to a vehicle such as an electric vehicle without mechanical contact such as a cable has been developed and put into practical use based on demand.
In this non-contact power feeding device, the secondary coil of the secondary circuit mounted on the vehicle or other moving body side from the primary coil of the primary circuit placed on the ground side based on the mutual induction action of electromagnetic induction. In addition, there is an air gap of about several tens to several hundreds of millimeters, and power is supplied while correspondingly positioned in a non-contact manner (see also FIG. 4 and the like described later)

<Conventional technology>
And this kind of non-contact electric power feeder is designed and manufactured as follows, considering various conditions conventionally.
That is, while assuming the required amount of power to be supplied, the distance between the air gap, the total electrical resistance of the secondary circuit, the frequency of the feeding AC, the turn ratio of the primary coil and the secondary coil, the core core Various conditions such as area (magnetic area of the formed magnetic flux), etc. are designed and manufactured so that the best coil performance and optimum inductance value can be obtained for the primary and secondary coils by mutual adjustment and setting. Has been.
Therefore, a high coupling coefficient is obtained for the primary side circuit and the secondary side circuit that are electromagnetically coupled, the excitation reactive power is small, and the effective active power on the secondary side can be extracted greatly. It is illustrated.

As such a non-contact electric power feeder, what was shown by the following patent document 1 and patent document 2 is mentioned, for example.
Japanese Patent Laid-Open No. 7-170681 JP 2008-087733 A

"problem"
By the way, the following subject was pointed out about such a conventional non-contact electric power feeder.
The power supply is premised on that the secondary coil mounted on the moving body side is accurately positioned based on a predetermined air gap with respect to the primary coil placed on the ground side. However, in actual operation, air gap fluctuations and position shifts inevitably occur frequently.
That is, the secondary coil is positioned with an air gap smaller than a predetermined air gap (over approaching), is positioned with a large air gap (excessive separation), or is displaced in the front-rear direction ( There were many cases where the position was shifted in the left-right direction (lateral shift). These often occur due to, for example, vehicle weight fluctuations and driving operations during power feeding.
And when such an air gap fluctuation | variation and position shift generate | occur | produced, the problem that electric power feeding efficiency changed and fell was pointed out.
That is, as described above, the air gap is an important factor for obtaining the best coil performance and the optimum value of inductance. When air gap fluctuations or misalignments occur, there is a concern that the inductance changes from the optimum value, the effective active power on the secondary side decreases, and power supply efficiency decreases.

<< About the present invention >>
In view of such a situation, the inductance-variable non-contact power feeding device of the present invention has been made to solve the above-described problems of the prior art.
In the first aspect of the present invention, the inductance that changes due to the air gap fluctuation and the positional deviation is changed and adjusted and corrected so as to maintain the optimum value, thereby avoiding a decrease in power supply efficiency, and secondly, this is a magnetic core. Proposing a non-contact power feeding device with variable inductance that can be easily and easily realized by making the core one core and two on each side into a set of three, making it possible to change the overall total surface area. With the goal.

<About each claim>
The technical means of the present invention for solving such a problem is as follows, as described in the claims.
This non-contact power feeding device with variable inductance is based on the mutual induction action of electromagnetic induction, and there is an air gap between the primary coil of the primary side circuit and the secondary coil of the secondary side circuit, and is positioned in a non-contact manner. Supply power.
The magnetic core attached to the primary coil and the secondary coil is made of a ferrite core and other ferromagnetic materials, has a flat plate shape, and has a one-piece structure of one sheet and two sheets on both sides.
The central magnetic core has the primary coil and the secondary coil spirally wound at the central portion thereof, and the side portions of both side magnetic cores are overlapped and slidably contacted at both ends.
The two-sided magnetic cores have the primary coil and the secondary coil wound around the central part of the central magnetic core corresponding to the size of the air gap fluctuation and the size of the positional deviation while interposing them in the center. , And can be slid linearly so as to separate or approach each other on both sides.

Therefore, the total total surface area of the core core formed by the combination of the central core core and the double-sided core cores, which are partially overlapped, can be varied widely, and the inductance of the primary coil and secondary coil can be varied. It has become.
Specifically, it is as follows.
First, when the air gap between the primary coil and the secondary coil becomes smaller than the setting due to the approach, the following occurs. Although the inductance is larger than the optimum value, the inductance is reduced and the optimum value of the inductance is maintained by sliding the both-side magnetic core so that the total total surface area of the magnetic core is reduced.
On the other hand, when the air gap between the primary coil and the secondary coil becomes larger than the setting due to separation or when the position is shifted, the following occurs. Although the inductance is smaller than the optimum value, the inductance is increased and the optimum value of the inductance is maintained by sliding the magnetic cores on both sides so that the total total surface area of the magnetic core is increased. Features.

<About the action>
Since the present invention comprises such means, the following is achieved.
(1) In the non-contact power feeding device, the secondary coil mounted on the vehicle or the like is positioned corresponding to the fixed primary coil under a predetermined air gap, and power feeding is performed. Yes.
(2) However, in actual operation, air gap fluctuations and misalignments are likely to occur. That is, the primary coil and the secondary coil often come closer to or away from the predetermined air gap distance. Further, there are many cases where the position is shifted from the corresponding position in the front-rear and left-right directions.
(3) Therefore, when an air gap variation or misalignment occurs, the total total surface area of the magnetic core can be changed correspondingly.
(4) That is, with respect to the magnetic core formed by the combination of the central magnetic core and the double-sided core that are partially overlapped, the two-core cores are linearly slid to move away from or approach each other. The total total surface area of the core is correspondingly varied.
(5) Therefore, the inductances of the primary coil and the secondary coil that have changed excessively or excessively based on the air gap fluctuation or positional deviation are further changed and adjusted and corrected by changing the total surface area of the magnetic core. The In this way, the inductance is maintained at an optimum value.
(6) In the non-contact power feeding device acting as described above, the magnetic core has a three-piece structure of one center and two on both sides, and the both side cores are linear with respect to the center core. It has a simple structure that is slidably contacted with each other.
(7) Since the magnetic core is formed by sliding the flat core cores on the flat central core, the overall thickness can be reduced.
(8) Furthermore, since the coil is wound around the central core, the magnetic core is formed with a dense magnetic flux density, allowing an increase in inductance and reducing the amount of coil used.
(9) Then, the non-contact power feeding device with variable inductance according to the present invention exhibits the following effects.

<< First effect >>
First, since the inductance that changes due to the air gap fluctuation and the positional deviation is maintained at the optimum value, a decrease in power supply efficiency is avoided.
That is, in the non-contact power feeding device with variable inductance according to the present invention, when the air gap fluctuates or the position shift occurs, the both-side magnetic cores can linearly slide relative to the central magnetic core.
Therefore, by changing the total total surface area of the magnetic core, the inductance that has changed excessively or too little due to air gap fluctuations or misalignment is changed, adjusted, and corrected to maintain the optimum value.
Therefore, a situation in which the power supply efficiency is reduced due to the air gap fluctuation or the position shift as in the above-described conventional example is avoided. That is, the coil performance is maintained in the best state, and the primary side circuit and the secondary side circuit that are electromagnetically coupled maintain a high coupling coefficient, the excitation reactive power is small, and the effective active power can be extracted largely on the secondary side. Thus, excellent power supply efficiency is maintained.

<< Second effect >>
Secondly, this can be easily and easily realized by using a single core and two on both sides so that the total surface area of the entire core can be varied.
That is, the inductance-variable non-contact power feeding device of the present invention easily realizes excellent power feeding efficiency as described above by a simple structure in which the magnetic core is a set of three sheets that can linearly slide.
Also, the magnetic core employed in the present invention is easy to manufacture because of its simple structure, and can be manufactured at low cost. In addition, one central magnetic core and two double-sided magnetic cores can be easily unified in shape, and can be manufactured at low cost from this aspect.
Further, the magnetic core of the present invention can be formed thinner than the so-called E-type magnetic core used in the above-described conventional example, so that, for example, downsizing is promoted.
Further, in the magnetic core of the present invention, since the coil is wound around the central magnetic core, the so-called flat plate type magnetic core used in the above-described conventional example (attached to the spirally wound coil). Inductance can be increased compared to Therefore, it is possible to reduce the amount of coil copper wire used, and this is also excellent in terms of cost.
As described above, the effects exerted by the present invention are remarkably large, such as all the problems existing in this type of conventional example are solved.

The inductance variable variable contactless power feeding device according to the present invention will be described for explaining the embodiment for carrying out the invention, showing its magnetic core and the like. (1) FIG. The front view of the operation when the gap is small, (3) is a front view of the operation when the air gap is large. For explanation of the mode for carrying out the invention, (1) is a plan view of a coil combination example, (2) is a front view of a coil winding mode example, (3) FIG. These are the front views of the example using a shape memory alloy. It is a circuit diagram for description of the non-contact power feeding device. For the description of the non-contact power feeding device, (1) is an overall side view, and (2) is a block diagram of the configuration.

Hereinafter, embodiments for carrying out the present invention will be described in detail.
<< About non-contact power feeding device A >>
First, a non-contact power feeding apparatus A that is a premise of the present invention will be generally described with reference to FIGS. 3 and 4.
The non-contact power feeding device A is non-contact with an air gap G from the primary coil 2 of the primary side circuit 1 to the secondary coil 4 of the secondary side circuit 3 based on the mutual induction action of electromagnetic induction. Supply power at the corresponding position. The primary side circuit 1 is fixedly arranged on the ground B side, and the secondary side circuit 3 is mounted on the moving body side such as the vehicle C side.

Such a non-contact power supply apparatus A will be described in further detail. First, the primary circuit 1 on the power supply side, the track side, and the primary side is stationaryly arranged on the ground, road surface, floor surface, and other ground B side in the power supply stand D and other power supply areas.
On the other hand, the secondary circuit 3 on the power receiving side, the pickup side, and the secondary side is mounted on an electric vehicle (EV car), a vehicle C such as a train, and other moving bodies. The secondary side circuit 3 can be used not only for driving a moving body but also for non-driving, and is typically connected to an in-vehicle battery 5 as shown in FIG. May be directly connected to various loads L.
The primary coil 2 of the primary side circuit 1 and the secondary coil 4 of the secondary side circuit 3 are air gaps G which are a slight gap space of several tens to several hundreds mm, for example, about 50 mm to 150 mm, during power feeding. However, they are positioned in close contact with each other in a non-contact manner. In the illustrated example, the corresponding positions are vertically located.
In addition, a stop power feeding method in which the secondary coil 4 is stopped at a corresponding position on the primary coil 2 or the like is typical for power feeding. On the other hand, a mobile power feeding method is also possible in which the secondary coil 4 feeds power while traveling on the primary coil 2 at a low speed.

The primary coil 2 of the primary side circuit 1 is connected to a power source 6 in which an inverter is used. In the primary circuit 1 of FIG. 3, 7 is a choke coil, 8 is a capacitor for series resonance with the primary coil 2, and 9 is a capacitor for parallel resonance with the primary coil 2. In the secondary side circuit 3 of FIG. 3, 10 is a capacitor for parallel resonance.
In addition, it is also conceivable to provide only one of the capacitors 8 or 9 for resonance (for series resonance or parallel resonance) for the primary side circuit 1 regardless of the illustrated example. It is also conceivable to provide a capacitor for series resonance in the secondary side circuit 3 together with or instead of the capacitor 10 for parallel resonance. Further, only one of the primary side circuit 1 and the secondary side circuit 3 may be a resonance circuit, and the other may not be provided with a resonance capacitor.
In the example of FIG. 4, the secondary coil 4 of the secondary side circuit 3 can be connected to the battery 5, and the traveling motor 11 is driven by the battery 5 charged by power feeding, whereas In the example 3, power is supplied to the other loads L. In FIG. 4, 12 is a converter (rectifying unit or smoothing unit) that converts alternating current into direct current, and 13 is an inverter that converts direct current into alternating current.

The mutual induction effect of electromagnetic induction is as follows. During power feeding, an induced electromotive force is generated in the secondary coil 4 by forming a magnetic flux in the primary coil 2 between the primary coil 2 and the secondary coil 4 that are located at the corresponding positions, so that the primary coil 2 changes to the secondary coil 4. Supplying electric power is publicly known.
That is, a magnetic field is generated around the primary coil 2 by applying and energizing the primary coil 2 of the primary side circuit 1 from the power supply 6 with, for example, an alternating current of several kHz to 100 kHz as a feeding alternating current or an exciting current. The magnetic flux is formed in a direction perpendicular to the coil surface.
And the magnetic flux formed in this way penetrates the secondary coil 4 of the secondary side circuit 3, and is linked and an induced electromotive force is produced | generated and a magnetic field is formed. In this way, electric power is transmitted and received using the induced magnetic field. It is also possible to supply power of about 1 kW to several kW or more, and about several tens kW to several hundred kW.
In the non-contact power feeding device A, a magnetic path of magnetic flux is formed between the primary coil 2 and the secondary coil 4 based on such mutual induction action of electromagnetic induction, the primary coil 2 and the primary side circuit 1, The secondary coil 4 and the secondary side circuit 3 are electromagnetically coupled to perform non-contact power feeding.
About the non-contact electric power feeder A, the general description is as above.

<< Outline of the Invention >>
Hereinafter, a non-contact power feeding apparatus A with variable inductance according to the present invention will be described with reference to FIG. First, the outline of the present invention is as follows.
In the non-contact power feeding apparatus A with variable inductance according to the present invention, the magnetic cores attached to the primary coil 2 and the secondary coil 4 in order to cope with fluctuations and displacements of the air gap G between the primary coil 2 and the secondary coil 4. The total total surface area of the core 14 can be changed, and the inductances of the primary coil 2 and the secondary coil 4 are variable.
That is, the magnetic core 14 is made of a ferrite core and other ferromagnetic materials, has a flat plate shape, and has a three-sheet structure of one sheet at the center and two sheets on both sides.
The central magnetic core 15 is formed by spirally winding the primary coil 2 and the secondary coil 4 at the central portion 16 thereof, and the side portions 20 and 21 of the both-side magnetic cores 18 and 19 are respectively provided at both end portions 17 thereof. Overlaid and slidably touched.
The both-side magnetic cores 18 and 19 are slidably contacted with the central magnetic core 15 so as to be linearly slidable. Therefore, the both-side magnetic cores 18 and 19 are formed by a combination of the central magnetic core 15 and the two-sided magnetic cores 18 and 19. The total total surface area of the magnetic core 14 to be formed can be changed widely.
The outline of the present invention is as described above. Hereinafter, the present invention will be described in detail.

<< Structure of magnetic core 14 >>
First, the structure of the magnetic core 14 will be described.
The magnetic core 14 is attached to the primary coil 2 and the secondary coil 4, is made of a ferromagnetic material, and a ferrite core is typically used. Then, the inductance of the primary coil 2 and the secondary coil 4 is increased to strengthen the electromagnetic coupling and to induce, collect and direct the formed magnetic flux.
In the present invention, as such a magnetic core 14, a three-piece one-piece structure with one center and two on both sides is adopted.
In the illustrated example, both the magnetic core 14 attached to the primary coil 2 and the magnetic core 14 attached to the secondary coil 4 have such a three-piece set structure. It should be noted that, regardless of the illustrated example, only one of the primary coil 2 or the secondary coil 4 is composed of such a three-core single-core magnetic core 14, and the other is a single flat sheet that has been conventionally used. A flat plate type (attached to a spirally wound coil), an E type magnetic core, or a central magnetic core 15 alone (both magnetic cores 18 and 19 do not exist) are also possible.

The three-core magnetic core 14 is composed of one central magnetic core 15 having a flat plate shape such as a rectangle, and two double-sided magnetic cores 18 and 19 having a rectangular flat plate shape. . Of course, various shapes other than the rectangular shape are possible, and it is not necessary to align the shapes of the central core core 15 and the two-sided cores 18 and 19 as shown in the figure.
The central magnetic core 15 has a coiled wire 2 ′ (insulated coated coil 4 ′ constituting the secondary coil 4) that is wound around the central portion 16. Has been.
Then, the side portions 20 and 21 of the both-side magnetic cores 18 and 19 are overlapped with the both end portions 17 of the central magnetic core 15, respectively. In the illustrated example, the right side 20 of the left magnetic core 18 is overlaid on the left end 17 of the central magnetic core 15, and the left side 21 of the right magnetic core 18 is overlaid on the right end 17 of the central magnetic core 15. (Note that the naming of the side portions 20 and 21 may be changed to the end portion, and the meaning of the terminology of the side portion used here is the same as the term end portion.)
At the same time, the two-sided magnetic cores 18 and 19 overlapped in this way are in sliding contact with the central magnetic core 15 so as to be linearly slidable. Therefore, the overlapping area with respect to the both side portions 17 of the central core 15 is variable with respect to the side portions 20 and 21 of the both side magnetic cores 18 and 19 based on the linear slide movement.
The structure of the magnetic core 14 is as described above.

<< Regarding the area of the magnetic core 14 >>
Next, the area of the magnetic core 14 will be described.
As described above, the double core cores 18 and 19 are slid relative to the central core core 15 so that the overlapping areas of the double core cores 18 and 19 with respect to the central core core 15 are variable.
And this sliding movement is implemented by the separation or approach between each other. In other words, the spirally wound primary coil 2 (secondary coil 4) of the central portion 16 of the central magnetic core 15 is interposed in the center, and can be slidably moved toward or away from the left and right sides in the drawing. It has become.
Therefore, the area of the magnetic core 14 can be changed as the both-side magnetic cores 18 and 19 slide. The magnetic core 14 is composed of a central magnetic core 15 and both-side magnetic cores 18 and 19, but the two-sided magnetic cores 18 and 19 that overlap the central magnetic core 15 slide and move, so that the area of the magnetic core 14 ( The overall surface area and the projected area can be varied.

Now, between the primary coil 2 stationary on the ground B side and the secondary coil 4 mounted on the moving body side such as the vehicle C, air gap G variation and positional deviation tend to occur frequently (so-called X , Y, Z direction, that is, forward / backward, left / right, up / down deviation).
When the air gap G variation or misalignment occurs, the inductance of the primary coil 2 or the secondary coil 4 (the self-inductance of the primary coil 2, the self-inductance of the secondary coil 4, the mutual inductance of the secondary coil 4, etc.) ) Changes from a predetermined optimum value (refer to the above description in the technical background of the background art column).
This can be dealt with by changing the inductance of the primary coil 2 and / or the secondary coil 4 by changing the area of the magnetic core 14 as described above.
That is, the both-side magnetic cores 18 and 19 of the magnetic core 14 are slidable so as to be separated from each other or close to each other according to the size of the air gap G and the size of the positional deviation. Accordingly, the entire area of the magnetic core 14 can be changed widely, and the inductance of the primary coil 2 and (illustrated example) / or the secondary coil 4 can be changed in size.
The area of the magnetic core 14 is as described above.

<Specific configuration>
Next, the above will be described with a specific configuration.
As shown in FIG. 1B, the case where the air gap G between the primary coil 2 and the secondary coil 4 becomes smaller than the setting due to the approach is as follows.
In this case, although the inductance is larger than the optimum value, the total total surface area of the magnetic core 14, specifically, the areas of the magnetic cores 14 on both the primary coil 2 side and the secondary coil 4 side are shown in the figure. The both-side magnetic cores 18 and 19 are slid so as to be narrow. As a result, the inductance is reduced and the optimum value of the inductance is maintained.
On the other hand, as shown in FIG. 1 (3), when the air gap G between the primary coil 2 and the secondary coil 4 becomes larger than the setting due to separation, the following (X, The same applies to the case of misalignment in the Y direction).
In this case, although the inductance is smaller than the optimum value, the total total surface area of the magnetic core 14, specifically, the areas of the magnetic cores 14 on both the primary coil 2 side and the secondary coil 4 side are shown in the figure. The both-side magnetic cores 18 and 19 are slid so as to become wider. As a result, the inductance becomes large and the optimum value of the inductance is maintained.
The specific configuration is as described above.

<Combination of multiple coils>
Next, a combination of a plurality of primary coils 2 and secondary coils 4 will be described.
In the example shown in FIG. 1, one primary coil 2 with a magnetic core 14 and one secondary coil 4 with a magnetic core 14 are used, and the corresponding positions are up and down. However, the present invention is not limited to such illustrated examples, and it is also possible to arrange a plurality of them in parallel so as to correspond to each other vertically.
In FIG. 2 (1), an example is shown in which two are arranged side by side so that the corresponding positions are up and down. That is, two primary coils 2 of the same standard with both magnetic cores 14 and two secondary coils 4 of the same standard with both magnetic cores 14 are arranged in the X direction (coil winding axis). 2 along the direction and the slide movement direction of the core, for example, the left-right direction of the vehicle C (longitudinal direction in the drawing), and the Y direction (for example, the front-rear direction of the vehicle C, the short direction in the drawing). They are arranged side by side.
In the example shown in FIG. 1, it is possible to effectively cope with the positional deviation in the X direction by sliding the both-side magnetic cores 18 and 19 of the magnetic core 14.
On the other hand, in a plurality of juxtaposed examples such as the example shown in FIG. 2 (1), both the core cores 14 of the magnetic core 14 are not only displaced in the X direction but also displaced in the Y direction. By slidably moving 18 and 19, it becomes possible to cope effectively.
In this case, the interval E between the magnetic cores 14 arranged side by side is set to be at least half of the width F of the magnetic cores 14. When approaching less than half, the leakage magnetic fluxes interfere with each other, causing a reduction in power supply efficiency.
The combination of multiple coils is as described above.

《Action etc.》
The inductance variable non-contact power feeding apparatus A of the present invention is configured as described above. Therefore, it becomes as follows.
(1) In the non-contact power feeding device A, the secondary coil 4 of the secondary side circuit 3 mounted on the vehicle C or the like is predetermined with respect to the primary coil 2 of the primary side circuit 1 placed on the ground B side. Under the gap size of the air gap G, power supply at the corresponding position and the opposite position is assumed accurately (see FIG. 4).

(2) However, in actual operation, fluctuations in the air gap G and misalignment tend to occur inevitably.
For example, due to weight fluctuation of the vehicle C at the time of power feeding, driving operation, or the like, excessive approach or separation may occur between the primary coil 2 and the secondary coil 4 due to a predetermined gap size of the air gap G. There are many. In many cases, the position is displaced from the corresponding position in the front-rear direction or the left-right direction.

  (3) When such an air gap G variation or misalignment occurs, in the non-contact power feeding device A of the present invention, the area of the magnetic core 14 can be changed as a countermeasure (FIG. 1). (See Figure (1)).

(4) That is, the magnetic core 14 slides so that the both-side magnetic cores 18 and 19 move away from each other or approach each other in accordance with the magnitude of the air gap G fluctuation and the position deviation.
Therefore, the combination of the central magnetic core 15 and the double-sided magnetic cores 18 and 19 that partially overlap each other causes the overlapped area to be formed and the total area of the magnetic core 14 to be changed correspondingly (see FIG. 1). (See Figure 2 and Figure 3).

(5) Therefore, the inductances of the primary coil 2 and the secondary coil 4 that have changed in size (excessively or excessively) based on fluctuations in the air gap G and displacement are further changed by changing the area of the magnetic core 14. I'm damned.
That is, when the inductance is increased due to the air gap G variation, the offset is offset, changed, and corrected to a small amount. When the inductance is decreased, the offset is offset, changed, and corrected to a greater extent. As a result, the inductance is maintained at a preset optimum value, and the power supply efficiency is maintained.

  (6) And this non-contact electric power feeding apparatus A which acts in this way makes the magnetic core 14 into one set of three pieces of one central piece and two pieces on both sides, and both the magnetic cores 18 and 19 to the central magnetic core 15 has a simple structure that is slidably contacted with respect to 15.

(7) Further, in the magnetic core 14, both end portions 17 of the flat central magnetic core 15 in which the coil conductors 2 ′ and 4 ′ of the primary coil 2 and the secondary coil 4 are spirally wound around the central portion 16. Similarly, the side portions 20 and 21 of the flat plate-like magnetic cores 18 and 19 are slidably provided so as to be slidable.
Therefore, the magnetic core 14 can be formed with a thin overall thickness. The wall thicknesses of the magnetic cores 18 and 19 on both sides are of a level commensurate with the helical winding thicknesses of the coil conductors 2 'and 4', and the overall thickness is not particularly increased.

(8) Further, in the magnetic core 14, coil conductors 2 ′ and 4 ′ of the primary coil 2 and the secondary coil 4 are spirally wound around the central magnetic core 15.
Therefore, since the formed magnetic flux density is dense and the inductance can be increased, the amount of use of the coil conductors 2 ′ and 4 ′ can be correspondingly reduced.
As for the action, it is as above.

<< Development of the present invention >>
By the way, about the non-contact electric power feeding apparatus A with variable inductance of this invention, the following 1st, 2nd structure etc. can be considered further.
First, the resonance conditions are as follows.
As described above, there is no particular problem because the resonance condition is also maintained when the inductance change based on the air gap G variation and the positional deviation is reliably changed and adjusted by changing the area of the magnetic core 14.
However, if a slight error (an error between the inductance change based on the air gap G variation or the like and the inductance change based on the change in the area of the magnetic core 14) occurs in both inductances (L), other resonances occur. Resonance is maintained by finely adjusting the frequency (f) of the power supply 6 and the capacitances of the capacitors (C) 8, 9, 10 and the like (see the following equation 1) (see FIG. 3). reference).
The resonance conditions are as described above.

Secondly, the spiral winding mode of the primary coil 2 and the secondary coil 4 is as follows.
For the primary coil 2 and the secondary coil 4 (coil conductors 2 ′ and 4 ′) wound around the central core 15 of the magnetic core 14 as shown in FIG. It is also possible to provide.
That is, as in the example shown in FIG. 1 and FIG. 2 (1), etc., instead of being densely and continuously spirally wound, as in the example shown in FIG. 2 (2), For example, a space may be provided in the central portion, and other constituent members may be disposed.
In the illustrated example, it is used for the alignment device 22 between the primary coil 2 and the secondary coil 4, and the reed switch 23 and the magnet 24 are arranged using the space.
About the spiral winding aspect of the primary coil 2 or the secondary coil 4, it is as above.

DESCRIPTION OF SYMBOLS 1 Primary side circuit 2 Primary coil 2 'coil conducting wire 3 Secondary side circuit 4 Secondary coil 4' coil conducting wire 5 Battery 6 Power supply 7 Choke coil 8 Capacitor 9 Capacitor 10 Capacitor 11 Motor 12 Converter 13 Inverter 14 Magnetic core 15 Center Magnetic core 16 Central portion 17 End portion 18 Double-sided magnetic core 19 Double-sided magnetic core 20 Side portion 21 Side portion 22 Positioning device 23 Reed switch 24 Magnet 25 Spring A Non-contact power feeding device B Ground C Vehicle D Feeding stand E Interval F Width G Air gap L Load X X direction Y Y direction

Claims (1)

In a non-contact power feeding device that supplies electric power from a primary coil of a primary-side circuit to a secondary coil of a secondary-side circuit based on the mutual induction action of electromagnetic induction and correspondingly positioned in a non-contact manner with an air gap. ,
The magnetic core attached to the primary coil and the secondary coil is made of a ferrite core and other ferromagnetic materials, has a flat plate shape, and has a one-piece structure consisting of one center and two sides.
The central magnetic core has the primary coil and the secondary coil spirally wound at the central portion thereof, and the side portions of both side magnetic cores are overlapped and slidably contacted at both ends.
The two-sided magnetic cores have the primary coil and the secondary coil wound around the central part of the central magnetic core corresponding to the size of the air gap fluctuation and the size of the positional deviation while interposing them in the center. , Can be slid linearly to move away or approach each other,
Therefore, the total total surface area of the core core formed by the combination of the central core core and the double-sided core cores, which are partially overlapped, can be varied widely, and the inductance of the primary coil and secondary coil can be varied. And
Specifically, when the air gap between the primary coil and the secondary coil becomes smaller than the setting due to the approach, the inductance becomes larger than the optimum value, but the total total surface area of the magnetic core is reduced. In addition, by sliding the magnetic cores on both sides, the inductance becomes small, and the optimum value of the inductance is maintained,
On the other hand, if the air gap between the primary coil and the secondary coil becomes larger than the setting due to separation or misalignment, the inductance will be smaller than the optimum value, but the total total of the magnetic core A non-contact power feeding apparatus with variable inductance, wherein the inductance is increased and the optimum value of the inductance is maintained by sliding the both-side magnetic cores so as to increase the surface area.

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