US20180240585A1 - Electromagnetic induction coil - Google Patents
Electromagnetic induction coil Download PDFInfo
- Publication number
- US20180240585A1 US20180240585A1 US15/956,237 US201815956237A US2018240585A1 US 20180240585 A1 US20180240585 A1 US 20180240585A1 US 201815956237 A US201815956237 A US 201815956237A US 2018240585 A1 US2018240585 A1 US 2018240585A1
- Authority
- US
- United States
- Prior art keywords
- coil
- electromagnetic induction
- primary
- main body
- resonance
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F27/00—Details of transformers or inductances, in general
- H01F27/006—Details of transformers or inductances, in general with special arrangement or spacing of turns of the winding(s), e.g. to produce desired self-resonance
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F27/00—Details of transformers or inductances, in general
- H01F27/28—Coils; Windings; Conductive connections
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F38/00—Adaptations of transformers or inductances for specific applications or functions
- H01F38/14—Inductive couplings
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J50/00—Circuit arrangements or systems for wireless supply or distribution of electric power
- H02J50/10—Circuit arrangements or systems for wireless supply or distribution of electric power using inductive coupling
- H02J50/12—Circuit arrangements or systems for wireless supply or distribution of electric power using inductive coupling of the resonant type
Definitions
- the present invention relates to an electromagnetic induction coil.
- the present invention relates to an electromagnetic induction coil used in non-contact power supply of resonance type.
- wireless power supply which does not use a power supply cord and a power transmission cable, as a power supply system that supplies power to a battery mounted on a hybrid automobile or an electric automobile.
- a technique of resonance type is known.
- a power supply system of resonance type for example, a supply system illustrated in FIG. 15 is proposed (Patent Literature 1).
- a power supply system 100 includes a primary coil unit 102 and a secondary coil unit 103 .
- the primary coil unit 102 is installed on the ground or the like of power supply facilities having an AC (alternating current) power supply 101 , to supply power from the AC power supply 101 without contact.
- the secondary coil unit 103 is mounted on a vehicle to receive power from the primary coil unit 102 without contact.
- the primary coil unit 102 includes a primary (power supply side) electromagnetic induction coil 104 , a primary resonance coil 105 , and a primary capacitor C 1 .
- the primary electromagnetic induction coil 104 is connected to the AC power supply 101 .
- the primary resonance coil 105 is supplied with power from the primary electromagnetic induction coil 104 by electromagnetic induction.
- the primary capacitor C 1 is connected to the primary resonance coil 105 to adjust a resonant frequency.
- the secondary coil unit 103 includes a secondary (power receipt side) resonance coil 106 , a secondary electromagnetic induction coil 107 , and a secondary capacitor C 2 .
- the secondary resonance coil 106 conducts magnetic field resonance with the primary resonance coil 105 .
- the secondary electromagnetic induction coil 107 is supplied with power from the secondary resonance coil 106 by electromagnetic induction and connected to a load 108 .
- the secondary capacitor C 2 is connected to the secondary resonance coil 106 to adjust the resonant frequency.
- the power supply system 100 when power from the AC power supply 101 is supplied to the primary electromagnetic induction coil 104 , the power is sent to the primary resonance coil 105 by electromagnetic induction. As a result, magnetic field resonance is caused between the primary resonance coil 105 and the secondary resonance coil 106 . Accordingly, wireless transmission of power from the primary resonance coil 105 to the secondary resonance coil 106 is conducted. In addition, the power sent to the secondary resonance coil 106 is sent to the secondary electromagnetic induction coil 107 by electromagnetic induction. The power is supplied to the load 108 connected to the secondary electromagnetic induction coil 107 .
- inter-coil distance a distance between the resonance coils 105 and 106
- position deviations of the resonance coils 105 and 106 occur. Occurrence of the distance variation and position deviations causes impedance mismatching. Consequently, power is reflected, resulting in lowered transmission efficiency.
- FIG. 16 is a graph indicating frequency characteristics of an S parameter S 21 between the resonance coils 105 and 106 in each of cases where the inter-coil distance is set equal to 100 mm, 200 mm, 300 mm and 400 mm in the power supply system 100 subjected to the impedance adjustment.
- impedance adjustment is conducted to make the transmission efficiency best when the inter-coil distance is 200 mm.
- FIG. 17 is a graph indicating the transmission efficiency between the resonance coils 105 and 106 as a function of the inter-coil distance in the power supply system 100 subjected to the impedance adjustment.
- the inter-coil distance becomes larger than 200 mm in the conventional power supply system 100 , coupling between the resonance coils 105 and 106 becomes weak accordingly and the S parameter S 21 becomes low, resulting in lowered transmission efficiency as illustrated in FIG. 17 .
- the inter-coil distance becomes smaller than 200 mm, the coupling between the resonance coils 105 and 106 becomes too strong accordingly and bi-resonant characteristics are brought about as illustrated in FIG. 16 .
- the S parameter S 21 at a transmission frequency (a frequency of the AC power supply 101 ) becomes lower and the transmission efficiency is lowered.
- Impedance matching can be executed by changing a capacitance.
- Patent Literature 1 JP 2009-501510A
- an object of the present invention to provide an electromagnetic induction coil used in a power supply system capable of conducting impedance adjustment and maintaining high efficiency without relying upon a variable capacitor.
- a coil serving as at least one coil among one pair of resonance coils that conduct non-contact power supply by magnetic field resonance, an electromagnetic induction coil that supplies power to a power supply side of the pair of resonance coils, or an electromagnetic induction coil supplied with power from a power receipt side of the pair of resonance coils.
- the coil has a coil main body, and an adjustment mechanism configured to adjust a number of turns of the coil main body.
- the adjustment mechanism consists of a mounting portion to mount an end portion of the coil main body and separate the end portion from other portions.
- a coil serving as at least one coil among one pair of resonance coils that conduct non-contact power supply by magnetic field resonance, an electromagnetic induction coil that supplies power to a power supply side of the pair of resonance coils, or an electromagnetic induction coil supplied with power from a power receipt side of the pair of resonance coils.
- the coil has a coil main body, and an adjustment mechanism configured to adjust a number of turns of the coil main body.
- the adjustment mechanism consists of a turn back portion provided by winding back a portion of the coil main body.
- the mounting portion has an inclined plane that becomes higher as a position approaches the end portion of the coil main body, and the end portion of the coil main body is mounted on the inclined plane.
- the turn back portion is provided on the end portion of the coil main body.
- impedance can be adjusted by adjusting the number of turns of the coil main body by means of the adjustment mechanism.
- impedance adjustment can be conducted without relying upon a variable capacitor. Consequently, non-conduct power supply can be conducted with high efficiency.
- the impedance can be adjusted simply by moving the mounting portion.
- the impedance can be adjusted simply by adjusting the length of the turn back portion.
- the end portion of the coil main body can be separated from other portions gently. As a result, no load is applied on the coil main body.
- the turn back portion can be provided easily.
- FIG. 1 is a diagram illustrating a power supply system incorporating an electromagnetic induction coil according to the present invention in a first embodiment
- FIG. 2 is a diagram illustrating a modification of the power supply system in the first embodiment
- FIG. 3 is a diagram illustrating a modification of the power supply system in the first embodiment
- FIG. 4 is a diagram illustrating a modification of the power supply system in the first embodiment
- FIG. 5 is a diagram illustrating a modification of the power supply system in the first embodiment
- FIG. 6 is a diagram illustrating a modification of the power supply system in the first embodiment
- FIG. 7 is a diagram illustrating a power supply system incorporating an electromagnetic induction coil according to the present invention in a second embodiment
- FIG. 8 is a graph illustrating results obtained by actually measuring the transmission efficiency as a function of the inter-coil distance with respect to a conventional article and a present invention article having a turn back portion;
- FIG. 9 is a graph illustrating results obtained by actually measuring the power loss rate as a function of the inter-coil distance with respect to a conventional article and a present invention article having the turn back portion;
- FIG. 10 is a diagram illustrating a modification of the power supply system in the second embodiment
- FIG. 11 is a diagram illustrating a modification of the power supply system in the second embodiment
- FIG. 12 is a diagram illustrating a modification of the power supply system in the second embodiment
- FIG. 13 is a diagram illustrating a modification of the power supply system in the second embodiment
- FIG. 14 is a diagram illustrating a modification of the power supply system in the second embodiment
- FIG. 15 is a diagram illustrating an example of a conventional power supply system
- FIG. 16 is a graph indicating frequency characteristics of an S parameter S 21 between resonance coils in each of cases where the inter-coil distance is set equal to 100 mm, 200 mm, 300 mm and 400 mm in a power supply system subjected to impedance adjustment to make the transmission efficiency best when the inter-coil distance is 200 mm;
- FIG. 17 is a graph indicating the transmission efficiency between resonance coils as a function of the inter-coil distance in a power supply system subjected to impedance adjustment to make the transmission efficiency best when the inter-coil distance is 200 mm.
- a power supply system 1 includes a primary coil unit 3 and a secondary coil unit 4 .
- the primary coil unit 3 is installed on the ground or the like of power supply facilities having an AC power supply 2 , to supply power from the AC power supply 2 without contact.
- the secondary coil unit 4 is mounted on a vehicle to receive power from the primary coil unit 3 without contact.
- the primary coil unit 3 includes a primary electromagnetic induction coil 5 , a primary resonance coil 6 , and a primary capacitor C 1 .
- the primary electromagnetic induction coil 5 is connected to the AC power supply 2 .
- the primary resonance coil 6 is supplied with power from the primary electromagnetic induction coil 5 by electromagnetic induction.
- the primary capacitor C 1 is connected to the primary resonance coil 6 to adjust the resonant frequency.
- the primary electromagnetic induction coil 5 corresponds to an electromagnetic induction coil and a coil in claims.
- the primary resonance coil 6 corresponds to a power supply side coil included in one pair of resonance coils in claims.
- the secondary coil unit 4 includes a secondary resonance coil 7 , a secondary electromagnetic induction coil 9 , and a secondary capacitor C 2 .
- the secondary resonance coil 7 conducts magnetic field resonance with the primary resonance coil 6 .
- the secondary electromagnetic induction coil 9 functions as an electromagnetic induction coil supplied with power from the secondary resonance coil 7 by electromagnetic induction and connected to a load 8 .
- the secondary capacitor C 2 is connected to the secondary resonance coil 7 to adjust the resonant frequency.
- the secondary electromagnetic induction coil 9 corresponds to an electromagnetic induction coil in claims.
- the secondary resonance coil 7 corresponds to a receipt side coil included in one pair of resonance coils in claims.
- Each of the primary electromagnetic induction coil 5 , the primary resonance coil 6 , the secondary resonance coil 7 , and the secondary electromagnetic induction coil 9 is wound in a spiral form on a holding member such as a substrate, which is not illustrated, and formed.
- the primary electromagnetic induction coil 5 and the primary resonance coil 6 are disposed on the same axis to be separated from each other.
- the primary electromagnetic induction coil 5 and the primary resonance coil 6 are disposed to have an axis direction along a direction in which the primary coil unit 3 and the secondary coil unit 4 are opposed to each other, i.e., along a vertical direction.
- the secondary resonance coil 7 and the secondary electromagnetic induction coil 9 are also disposed on the same axis to be separated from each other, and disposed to have an axis direction along the vertical direction.
- the primary electromagnetic induction coil 5 , the primary resonance coil 6 , the secondary resonance coil 7 , and the secondary electromagnetic induction coil 9 are disposed on the same axis.
- the power supply system 1 when power from the AC power supply 2 is supplied to the primary electromagnetic induction coil 5 , the power is sent to the primary resonance coil 6 by electromagnetic induction in the same way as the conventional system. As a result, magnetic field resonance is caused between the primary resonance coil 6 and the secondary resonance coil 7 . Accordingly, wireless transmission of power from the primary resonance coil 6 to the secondary resonance coil 7 is conducted. In addition, the power sent to the secondary resonance coil 7 is sent to the secondary electromagnetic induction coil 9 by electromagnetic induction. The power is supplied to the load 8 connected to the secondary electromagnetic induction coil 9 .
- the primary electromagnetic induction coil 5 includes a coil main body 51 and a wedge W functioning as an adjustment mechanism for adjusting a number of turns of the coil main body, which mount a first end portion (in the present embodiment, an outside end portion) of the coil main body 51 and separate the first end portion from other portions.
- the adjustment mechanism consists of a mounting portion.
- the coil main body 51 includes a wire material having flexibility.
- the coil main body 51 is disposed on a holding member such as a substrate, which is not illustrated, as above-described.
- the wire material having flexibility is wound in a circular-shaped spiral form.
- the wedge W is mounted on a flat plate on which the coil main body 51 is disposed.
- the wedge W is provided in a nearly box form.
- the wedge W is provided in an elongated form along a winding direction Y 1 of the coil main body 51 .
- the wedge W is provided to curve along the winding direction Y 1 .
- An inclined plane W 1 is provided on the wedge W.
- the inclined plane W 1 becomes higher as the position approaches the first end portion of the coil main body 51 .
- a line shaped accommodation groove W 2 is provided on the inclined plane W 1 to accommodate the first end portion of the coil main body 51 .
- the first end portion of the coil main body 51 is accommodated in the line shaped accommodation groove W 2 .
- the first end portion of the coil main body 51 which is a portion mounted on the wedge W, is separated from other portions in a height direction. Therefore, the portion of the coil main body 51 mounted on the wedge W does not contribute to the function exhibited as a coil. If the wedge W is moved to a side apart from the first end portion of the coil main body 51 , the wedge W moves clockwise in FIG. 1 . As a result, the length of an end portion of the coil main body 51 mounted on the wedge W increases and the number of turns of the coil main body 51 can be decreased.
- an inter-coil distance D is large due to, for example, an installation environment of the primary coil unit 3 and the secondary coil unit 4 .
- the wedge W is moved clockwise in FIG. 1 to decrease the number of turns of the coil main body 51 , in the above-described power supply system 1 .
- impedance matching can be achieved by decreasing the number of turns of the coil main body 51 , i.e., an inductance L and a mutual inductance M.
- the inter-coil distance D is small, the number of turns of the coil main body 51 is increased by moving the wedge W counterclockwise in FIG. 1 .
- impedance matching can be achieved by increasing the number of turns of the coil main body 51 , i.e., the inductance L and the mutual inductance M to eliminate the bi-resonant characteristics.
- impedance can be adjusted simply by moving the wedge W.
- the inclined plane W 1 which becomes higher as the position approaches the first end portion of the coil main body 51 , is provided on the wedge W, and the first end portion of the coil main body 51 is mounted on the inclined plane W 1 .
- the end portion of the coil main body 51 can be separated from other portions gently, and consequently no load is applied on the coil main body 51 .
- the wedge W is provided in the primary electromagnetic induction coil 5 wound in the spiral form.
- the shape of a coil in which the wedge W can be provided is not restricted to this.
- the shape of the coil may be another well-known shape.
- the wedge W is mounted on a holding member (not illustrated), which holds the coil main body 51 of the primary electromagnetic induction coil 5 , such as a bobbin in the same way as the first embodiment.
- the primary resonance coil 6 , the secondary resonance coil 7 , and the secondary electromagnetic induction coil 9 are also wound in a helical form and formed. In this case as well, effects similar to those in the first embodiment can be obtained.
- the present invention is not restricted to this. Only a second end portion of the coil main body 51 may be mounted on the wedge W. Both end portions of the coil main body 51 may be mounted on the wedge W.
- the wedge W is provided only in the primary electromagnetic induction coil 5 .
- the present invention is not restricted to this.
- the wedge W may be provided only in the secondary electromagnetic induction coil 9 .
- the wedge W may be provided in both the primary electromagnetic induction coil 5 and the secondary electromagnetic induction coil 9 .
- each of the primary electromagnetic induction coil 5 , the primary resonance coil 6 , the secondary resonance coil 7 , and the secondary electromagnetic induction coil 9 is provided to have an axis in the vertical direction.
- disposition of the coils is not restricted to this. For example, it is conceivable to dispose the coils as illustrated in FIG. 3 .
- the primary electromagnetic induction coil 5 and the primary resonance coil 6 are wound round a flat plate shaped primary core 10 in a helical form. As a result, the primary electromagnetic induction coil 5 and the primary resonance coil 6 are disposed on the same axis.
- the secondary resonance coil 7 and the secondary electromagnetic induction coil 9 are also wound round a flat plate shaped secondary core 11 in a helical form. As a result, the secondary resonance coil 7 and the secondary electromagnetic induction coil 9 are disposed on the same axis.
- the primary core 10 and the secondary core 11 are disposed side by side to be parallel to each other. Therefore, an axis of each of the primary electromagnetic induction coil 5 , the primary resonance coil 6 , the secondary resonance coil 7 , and the secondary electromagnetic induction coil 9 is disposed in a horizontal direction.
- the horizontal direction is a direction perpendicular to a direction in which the primary coil unit 3 and the secondary coil unit 4 are opposed to each other.
- the above-described primary electromagnetic induction coil 5 includes a coil main body 51 and a wedge W in the same way as the first embodiment.
- the wedge W is mounted on the primary core 10 , which is a holding member.
- the wedge W is provided in an elongated form along a winding direction of the coil main body 51 .
- the wedge W is provided in a straight-line form along the winding direction.
- An inclined plane W 1 is provided on the wedge W.
- the inclined plane W 1 becomes higher as the position approaches a first end portion of the coil main body 51 .
- a line shaped accommodation groove W 2 is provided on the inclined plane W 1 to accommodate the end portion of the coil main body 51 .
- the end portion of the coil main body 51 is accommodated in the line shaped accommodation groove W 2 .
- a wedge W is provided in the secondary electromagnetic induction coil 9 as well to mount a first end portion of a coil main body 91 and separate the first end portion from other portions.
- impedance matching can be achieved by moving the wedge W in the same way as the first embodiment and changing the number of turns of each of the coil main bodies 51 and 91 .
- the wedges W are provided in both the primary electromagnetic induction coil 5 and the secondary electromagnetic induction coil 9 .
- the wedge W may be provided only in the primary electromagnetic induction coil 5 .
- the wedge W may be provided only in the secondary electromagnetic induction coil 9 .
- each of the primary and secondary electromagnetic induction coils 5 and 9 is mounted on the wedge W.
- the resonance coils 6 and 7 may include coil main bodies 61 and 71 , respectively and the wedges W.
- the resonance coils 6 and 7 are formed in a spiral form.
- the wedges W may be provided in helical resonance coils 6 and 7 .
- the wedges W may be provided in resonance coils 6 and 7 having axes disposed in the horizontal direction.
- the resonant frequency of the resonance coils 6 and 7 deviates due to not only the variation of the inter-coil distance D but also variations in manufacture of the resonance coils 6 and 7 , the capacitors C 1 and C 2 , ferrite and coil bobbins.
- impedance adjustment can be conducted.
- the inclined plane W 1 and the line shaped accommodation groove W 2 are provided.
- the present invention is not restricted to this.
- the inclined plane W 1 and the line shaped accommodation groove W 2 may not be provided.
- a power supply system 1 incorporating an electromagnetic induction coil according to the present invention in a second embodiment will now be described with reference to FIG. 7 .
- the second embodiment differs from the first embodiment in configuration of the adjustment mechanism. Other portions are similar to those in the first embodiment illustrated in FIG. 1 . Therefore, detailed description of other portions will be omitted.
- the wedge W is provided as the adjustment mechanism.
- a turn back portion T provided by winding back a first end portion of a coil main body 51 becomes the adjustment mechanism.
- the turn back portion T In the turn back portion T, magnetic fluxes generated from a portion along a winding direction and a portion along a wind back direction, which are adjacent to each other, cancel each other. Therefore, the turn back portion does not contribute to the function exhibited as a coil. If the turn back portion T is made large, therefore, the number of turns of the coil main body 51 can be decreased. On the other hand, if the turn back portion T is made small, the number of turns of the coil main body 51 can be increased.
- an inter-coil distance D is large due to, for example, an installation environment of the primary coil unit 3 and the secondary coil unit 4 .
- the turn back portion T is made large to decrease the number of turns of the coil main body 51 , in the above-described power supply system 1 .
- impedance matching can be achieved by decreasing the number of turns of the coil main body 51 , i.e., an inductance L and a mutual inductance M.
- the inter-coil distance D is small, the number of turns of the coil main body 51 is increased by making the turn back portion T small.
- impedance matching can be achieved by increasing the number of turns of the coil main body 51 , i.e., the inductance L and the mutual inductance M to eliminate the bi-resonant characteristics.
- impedance can be adjusted simply by adjusting the length of the turn back portion T.
- the turn back portion T can be provided easily by providing the turn back portion T in the end portion of the coil main body 51 .
- the present inventor actually measured the transmission efficiency as a function of the inter-coil distance with respect to a conventional article, which is a conventional power supply system having no turn back portion T, and a present invention article, which is the power supply system 1 according to the present invention having the turn back portion T. Results are illustrated in FIG. 8 . As for the present invention article, the highest transmission efficiency is plotted by adjusting the length of the turn back portion T.
- the transmission efficiency of at least 90% can be kept in the conventional article only when the inter-coil distance D is in the range of 180 mm to 210 mm.
- the transmission efficiency of at least 90% can be kept in a wide range of the inter-coil distance D of 180 mm to 250 mm.
- the present inventor actually measured the power loss rate as a function of the inter-coil distance D with respect to the conventional article and the present invention article. Results are illustrated in FIG. 9 .
- the lowest power loss rate is plotted by adjusting the length of the turn back portion T.
- the power loss rate becomes large as the inter-coil distance D is separated from 200 mm.
- the power loss rate can be made equal to 0% in a wide range of the inter-coil distance D of 180 mm to 250 mm.
- the turn back portion T is provided in the primary electromagnetic induction coil 5 wound in the spiral form.
- the shape of a coil in which the turn back portion T can be provided is not restricted to this.
- the shape of the coil may be another well-known shape.
- each of the primary electromagnetic induction coil 5 , the primary resonance coil 6 , the secondary resonance coil 7 , and the secondary electromagnetic induction coil 9 is provided to have an axis in the vertical direction.
- disposition of the coils is not restricted to this.
- the secondary resonance coil 7 and the secondary electromagnetic induction coil 9 are similar to those in FIG. 3 , they are omitted from FIG. 11 .
- the turn back portion T is provided on the first end of the coil main body 51 .
- the turn back portion T may be provided on a second end of the coil main body 51 .
- the turn back portion T may be provided on both ends of the coil main body 51 .
- the turn back portion T is not restricted to end portions. For example, it is also conceivable to provide the turn back portion T in a central portion of the coil main body 51 .
- the turn back portion T is provided only in the primary electromagnetic induction coil 5 .
- the turn back portion T may be provided only in the secondary electromagnetic induction coil 9 . It is also conceivable to provide the turn back portion T in both the primary electromagnetic induction coil 5 and the secondary electromagnetic induction coil 9 .
- each of the coil main bodies 51 and 91 has a plurality of turns (at least two turns). However, each of the coil main bodies 51 and 91 may have one turn.
- the turn back portion T is provided in the primary and secondary electromagnetic induction coils 5 and 9 .
- the resonance coils 6 and 7 may include coil main bodies 61 and 71 , respectively and the turn back portions T.
- the resonance coils 6 and 7 are formed in a spiral form.
- the turn back portions T may be provided in resonance coils 6 and 7 having an axis disposed in the horizontal direction.
- the turn back portions T may be provided in helical resonance coils 6 and 7 .
- the resonant frequency of the resonance coils 6 and 7 deviates due to not only the variation of the inter-coil distance D but also variations in manufacture of the resonance coils 6 and 7 , the capacitors C 1 and C 2 , ferrite, and coil bobbins.
- impedance adjustment can be conducted.
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Computer Networks & Wireless Communication (AREA)
- Current-Collector Devices For Electrically Propelled Vehicles (AREA)
- Electric Propulsion And Braking For Vehicles (AREA)
- Coils Or Transformers For Communication (AREA)
Abstract
A primary electromagnetic induction coil, which supplies power to a primary resonance coil in a pair of a primary and a secondary resonance coils that conduct non-contact power supply by magnetic field resonance, includes a coil main body and a wedge that mounts an end portion of the coil main body to separate the end portion from other portions. Impedance matching can be achieved by adjusting a position of the wedge and a number of turns of the coil main body.
Description
- The present invention relates to an electromagnetic induction coil. In particular, the present invention relates to an electromagnetic induction coil used in non-contact power supply of resonance type.
- In recent years, attention has been paid to wireless power supply, which does not use a power supply cord and a power transmission cable, as a power supply system that supplies power to a battery mounted on a hybrid automobile or an electric automobile. As one of techniques of the wireless power supply, a technique of resonance type is known.
- As the power supply system of resonance type, for example, a supply system illustrated in
FIG. 15 is proposed (Patent Literature 1). As illustrated inFIG. 15 , apower supply system 100 includes aprimary coil unit 102 and asecondary coil unit 103. Theprimary coil unit 102 is installed on the ground or the like of power supply facilities having an AC (alternating current)power supply 101, to supply power from theAC power supply 101 without contact. Thesecondary coil unit 103 is mounted on a vehicle to receive power from theprimary coil unit 102 without contact. - The
primary coil unit 102 includes a primary (power supply side)electromagnetic induction coil 104, aprimary resonance coil 105, and a primary capacitor C1. The primaryelectromagnetic induction coil 104 is connected to theAC power supply 101. Theprimary resonance coil 105 is supplied with power from the primaryelectromagnetic induction coil 104 by electromagnetic induction. The primary capacitor C1 is connected to theprimary resonance coil 105 to adjust a resonant frequency. - The
secondary coil unit 103 includes a secondary (power receipt side)resonance coil 106, a secondaryelectromagnetic induction coil 107, and a secondary capacitor C2. Thesecondary resonance coil 106 conducts magnetic field resonance with theprimary resonance coil 105. The secondaryelectromagnetic induction coil 107 is supplied with power from thesecondary resonance coil 106 by electromagnetic induction and connected to aload 108. The secondary capacitor C2 is connected to thesecondary resonance coil 106 to adjust the resonant frequency. - According to the above-described
power supply system 100, when power from theAC power supply 101 is supplied to the primaryelectromagnetic induction coil 104, the power is sent to theprimary resonance coil 105 by electromagnetic induction. As a result, magnetic field resonance is caused between theprimary resonance coil 105 and thesecondary resonance coil 106. Accordingly, wireless transmission of power from theprimary resonance coil 105 to thesecondary resonance coil 106 is conducted. In addition, the power sent to thesecondary resonance coil 106 is sent to the secondaryelectromagnetic induction coil 107 by electromagnetic induction. The power is supplied to theload 108 connected to the secondaryelectromagnetic induction coil 107. - When the
power supply system 100 is mounted on power supply facilities or a vehicle, however, a variation of a distance between theresonance coils 105 and 106 (hereafter abbreviated to “inter-coil distance”) and position deviations of theresonance coils - This will now be described in more detail with reference to
FIGS. 16 and 17 . In thepower supply system 100, impedance adjustment is conducted to make the transmission efficiency best when the inter-coil distance is 200 mm.FIG. 16 is a graph indicating frequency characteristics of an S parameter S21 between theresonance coils power supply system 100 subjected to the impedance adjustment. In thepower supply system 100, impedance adjustment is conducted to make the transmission efficiency best when the inter-coil distance is 200 mm.FIG. 17 is a graph indicating the transmission efficiency between theresonance coils power supply system 100 subjected to the impedance adjustment. - If the inter-coil distance becomes larger than 200 mm in the conventional
power supply system 100, coupling between theresonance coils FIG. 17 . If the inter-coil distance becomes smaller than 200 mm, the coupling between theresonance coils FIG. 16 . As a result, the S parameter S21 at a transmission frequency (a frequency of the AC power supply 101) becomes lower and the transmission efficiency is lowered. - As a countermeasure against the above-described inter-coil distance and position deviation, it is usually considered to provide a matching circuit in the
primary coil unit 102 or the secondary coil unit 103 (or in both theprimary coil unit 102 and thesecondary coil unit 103 in some cases) to conduct impedance matching. A variable capacitor is provided in the matching circuit. Impedance matching can be executed by changing a capacitance. - In a case where the frequency of the transmission frequency is in a kHz region, however, a capacitor having a large capacitance is needed. It is inevitable to use a film capacitor or a ceramic capacitor. However, there is a problem that it is difficult to make the film capacitor or a ceramic capacitor variable.
- Patent Literature 1: JP 2009-501510A
- Therefore, it is an object of the present invention to provide an electromagnetic induction coil used in a power supply system capable of conducting impedance adjustment and maintaining high efficiency without relying upon a variable capacitor.
- In order to attain the above object, according to a first aspect, a coil serving as at least one coil among one pair of resonance coils that conduct non-contact power supply by magnetic field resonance, an electromagnetic induction coil that supplies power to a power supply side of the pair of resonance coils, or an electromagnetic induction coil supplied with power from a power receipt side of the pair of resonance coils. The coil has a coil main body, and an adjustment mechanism configured to adjust a number of turns of the coil main body. The adjustment mechanism consists of a mounting portion to mount an end portion of the coil main body and separate the end portion from other portions.
- Preferably, according to a second aspect, a coil serving as at least one coil among one pair of resonance coils that conduct non-contact power supply by magnetic field resonance, an electromagnetic induction coil that supplies power to a power supply side of the pair of resonance coils, or an electromagnetic induction coil supplied with power from a power receipt side of the pair of resonance coils. The coil has a coil main body, and an adjustment mechanism configured to adjust a number of turns of the coil main body. The adjustment mechanism consists of a turn back portion provided by winding back a portion of the coil main body.
- Preferably, according to a third aspect, the mounting portion has an inclined plane that becomes higher as a position approaches the end portion of the coil main body, and the end portion of the coil main body is mounted on the inclined plane.
- Preferably, according to a fourth aspect, the turn back portion is provided on the end portion of the coil main body.
- According to the present invention of the first aspect, impedance can be adjusted by adjusting the number of turns of the coil main body by means of the adjustment mechanism. As a result, impedance adjustment can be conducted without relying upon a variable capacitor. Consequently, non-conduct power supply can be conducted with high efficiency. Further, the impedance can be adjusted simply by moving the mounting portion.
- According to the present invention of the second aspect, the impedance can be adjusted simply by adjusting the length of the turn back portion.
- According to the present invention of the third aspect, the end portion of the coil main body can be separated from other portions gently. As a result, no load is applied on the coil main body.
- According to the present invention of the fourth aspect, the turn back portion can be provided easily.
-
FIG. 1 is a diagram illustrating a power supply system incorporating an electromagnetic induction coil according to the present invention in a first embodiment; -
FIG. 2 is a diagram illustrating a modification of the power supply system in the first embodiment; -
FIG. 3 is a diagram illustrating a modification of the power supply system in the first embodiment; -
FIG. 4 is a diagram illustrating a modification of the power supply system in the first embodiment; -
FIG. 5 is a diagram illustrating a modification of the power supply system in the first embodiment; -
FIG. 6 is a diagram illustrating a modification of the power supply system in the first embodiment; -
FIG. 7 is a diagram illustrating a power supply system incorporating an electromagnetic induction coil according to the present invention in a second embodiment; -
FIG. 8 is a graph illustrating results obtained by actually measuring the transmission efficiency as a function of the inter-coil distance with respect to a conventional article and a present invention article having a turn back portion; -
FIG. 9 is a graph illustrating results obtained by actually measuring the power loss rate as a function of the inter-coil distance with respect to a conventional article and a present invention article having the turn back portion; -
FIG. 10 is a diagram illustrating a modification of the power supply system in the second embodiment; -
FIG. 11 is a diagram illustrating a modification of the power supply system in the second embodiment; -
FIG. 12 is a diagram illustrating a modification of the power supply system in the second embodiment; -
FIG. 13 is a diagram illustrating a modification of the power supply system in the second embodiment; -
FIG. 14 is a diagram illustrating a modification of the power supply system in the second embodiment; -
FIG. 15 is a diagram illustrating an example of a conventional power supply system; -
FIG. 16 is a graph indicating frequency characteristics of an S parameter S21 between resonance coils in each of cases where the inter-coil distance is set equal to 100 mm, 200 mm, 300 mm and 400 mm in a power supply system subjected to impedance adjustment to make the transmission efficiency best when the inter-coil distance is 200 mm; and -
FIG. 17 is a graph indicating the transmission efficiency between resonance coils as a function of the inter-coil distance in a power supply system subjected to impedance adjustment to make the transmission efficiency best when the inter-coil distance is 200 mm. - Hereafter, a power supply system incorporating an electromagnetic induction coil according to the present invention in a first embodiment will be described with reference to
FIG. 1 . As illustrated inFIG. 1 , a power supply system 1 includes aprimary coil unit 3 and asecondary coil unit 4. Theprimary coil unit 3 is installed on the ground or the like of power supply facilities having anAC power supply 2, to supply power from theAC power supply 2 without contact. Thesecondary coil unit 4 is mounted on a vehicle to receive power from theprimary coil unit 3 without contact. - The
primary coil unit 3 includes a primaryelectromagnetic induction coil 5, aprimary resonance coil 6, and a primary capacitor C1. The primaryelectromagnetic induction coil 5 is connected to theAC power supply 2. Theprimary resonance coil 6 is supplied with power from the primaryelectromagnetic induction coil 5 by electromagnetic induction. The primary capacitor C1 is connected to theprimary resonance coil 6 to adjust the resonant frequency. The primaryelectromagnetic induction coil 5 corresponds to an electromagnetic induction coil and a coil in claims. Theprimary resonance coil 6 corresponds to a power supply side coil included in one pair of resonance coils in claims. - The
secondary coil unit 4 includes asecondary resonance coil 7, a secondaryelectromagnetic induction coil 9, and a secondary capacitor C2. Thesecondary resonance coil 7 conducts magnetic field resonance with theprimary resonance coil 6. The secondaryelectromagnetic induction coil 9 functions as an electromagnetic induction coil supplied with power from thesecondary resonance coil 7 by electromagnetic induction and connected to aload 8. The secondary capacitor C2 is connected to thesecondary resonance coil 7 to adjust the resonant frequency. The secondaryelectromagnetic induction coil 9 corresponds to an electromagnetic induction coil in claims. Thesecondary resonance coil 7 corresponds to a receipt side coil included in one pair of resonance coils in claims. - Each of the primary
electromagnetic induction coil 5, theprimary resonance coil 6, thesecondary resonance coil 7, and the secondaryelectromagnetic induction coil 9 is wound in a spiral form on a holding member such as a substrate, which is not illustrated, and formed. The primaryelectromagnetic induction coil 5 and theprimary resonance coil 6 are disposed on the same axis to be separated from each other. The primaryelectromagnetic induction coil 5 and theprimary resonance coil 6 are disposed to have an axis direction along a direction in which theprimary coil unit 3 and thesecondary coil unit 4 are opposed to each other, i.e., along a vertical direction. - The
secondary resonance coil 7 and the secondaryelectromagnetic induction coil 9 are also disposed on the same axis to be separated from each other, and disposed to have an axis direction along the vertical direction. When theprimary coil unit 3 and thesecondary coil unit 4 are opposed to each other, therefore, the primaryelectromagnetic induction coil 5, theprimary resonance coil 6, thesecondary resonance coil 7, and the secondaryelectromagnetic induction coil 9 are disposed on the same axis. - According to the above-described power supply system 1, when power from the
AC power supply 2 is supplied to the primaryelectromagnetic induction coil 5, the power is sent to theprimary resonance coil 6 by electromagnetic induction in the same way as the conventional system. As a result, magnetic field resonance is caused between theprimary resonance coil 6 and thesecondary resonance coil 7. Accordingly, wireless transmission of power from theprimary resonance coil 6 to thesecondary resonance coil 7 is conducted. In addition, the power sent to thesecondary resonance coil 7 is sent to the secondaryelectromagnetic induction coil 9 by electromagnetic induction. The power is supplied to theload 8 connected to the secondaryelectromagnetic induction coil 9. - An example of the primary
electromagnetic induction coil 5, which is a feature of the present invention, will now be described. The primaryelectromagnetic induction coil 5 includes a coilmain body 51 and a wedge W functioning as an adjustment mechanism for adjusting a number of turns of the coil main body, which mount a first end portion (in the present embodiment, an outside end portion) of the coilmain body 51 and separate the first end portion from other portions. The adjustment mechanism consists of a mounting portion. The coilmain body 51 includes a wire material having flexibility. The coilmain body 51 is disposed on a holding member such as a substrate, which is not illustrated, as above-described. The wire material having flexibility is wound in a circular-shaped spiral form. - The wedge W is mounted on a flat plate on which the coil
main body 51 is disposed. The wedge W is provided in a nearly box form. The wedge W is provided in an elongated form along a winding direction Y1 of the coilmain body 51. The wedge W is provided to curve along the winding direction Y1. An inclined plane W1 is provided on the wedge W. The inclined plane W1 becomes higher as the position approaches the first end portion of the coilmain body 51. A line shaped accommodation groove W2 is provided on the inclined plane W1 to accommodate the first end portion of the coilmain body 51. The first end portion of the coilmain body 51 is accommodated in the line shaped accommodation groove W2. - The first end portion of the coil
main body 51, which is a portion mounted on the wedge W, is separated from other portions in a height direction. Therefore, the portion of the coilmain body 51 mounted on the wedge W does not contribute to the function exhibited as a coil. If the wedge W is moved to a side apart from the first end portion of the coilmain body 51, the wedge W moves clockwise inFIG. 1 . As a result, the length of an end portion of the coilmain body 51 mounted on the wedge W increases and the number of turns of the coilmain body 51 can be decreased. - On the other hand, if the wedge W is moved toward the first end portion of the coil
main body 51, the wedge W moves counterclockwise inFIG. 1 . As a result, the length of the end portion of the coilmain body 51 mounted on the wedge W decreases and the number of turns of the coilmain body 51 can be increased. - In some cases, an inter-coil distance D is large due to, for example, an installation environment of the
primary coil unit 3 and thesecondary coil unit 4. In this case, the wedge W is moved clockwise inFIG. 1 to decrease the number of turns of the coilmain body 51, in the above-described power supply system 1. As a result, impedance matching can be achieved by decreasing the number of turns of the coilmain body 51, i.e., an inductance L and a mutual inductance M. On the other hand, in a case where the inter-coil distance D is small, the number of turns of the coilmain body 51 is increased by moving the wedge W counterclockwise inFIG. 1 . - As a result, impedance matching can be achieved by increasing the number of turns of the coil
main body 51, i.e., the inductance L and the mutual inductance M to eliminate the bi-resonant characteristics. As a result, it is possible to conduct impedance adjustment and conduct non-contact power supply with high efficiency without relying upon a variable capacitor. Furthermore, the impedance can be adjusted simply by moving the wedge W. - According to the above-described power supply system 1, the inclined plane W1, which becomes higher as the position approaches the first end portion of the coil
main body 51, is provided on the wedge W, and the first end portion of the coilmain body 51 is mounted on the inclined plane W1. As a result, the end portion of the coilmain body 51 can be separated from other portions gently, and consequently no load is applied on the coilmain body 51. - In the above-described first embodiment, the wedge W is provided in the primary
electromagnetic induction coil 5 wound in the spiral form. However, the shape of a coil in which the wedge W can be provided is not restricted to this. The shape of the coil may be another well-known shape. For example, it is conceivable to provide the wedge W in the primaryelectromagnetic induction coil 5 wound in a helical form as illustrated inFIG. 2 . The wedge W is mounted on a holding member (not illustrated), which holds the coilmain body 51 of the primaryelectromagnetic induction coil 5, such as a bobbin in the same way as the first embodiment. InFIG. 2 , theprimary resonance coil 6, thesecondary resonance coil 7, and the secondaryelectromagnetic induction coil 9 are also wound in a helical form and formed. In this case as well, effects similar to those in the first embodiment can be obtained. - In the above-described first embodiment and the modification illustrated in
FIG. 2 , only the first end portion of the coilmain body 51 is mounted on the wedge W. - However, the present invention is not restricted to this. Only a second end portion of the coil
main body 51 may be mounted on the wedge W. Both end portions of the coilmain body 51 may be mounted on the wedge W. - In the above-described first embodiment and the modification illustrated in
FIG. 2 , the wedge W is provided only in the primaryelectromagnetic induction coil 5. However, the present invention is not restricted to this. For example, the wedge W may be provided only in the secondaryelectromagnetic induction coil 9. The wedge W may be provided in both the primaryelectromagnetic induction coil 5 and the secondaryelectromagnetic induction coil 9. - In the above-described first embodiment and the modification illustrated in
FIG. 2 , each of the primaryelectromagnetic induction coil 5, theprimary resonance coil 6, thesecondary resonance coil 7, and the secondaryelectromagnetic induction coil 9 is provided to have an axis in the vertical direction. However, disposition of the coils is not restricted to this. For example, it is conceivable to dispose the coils as illustrated inFIG. 3 . - As illustrated in
FIG. 3 , the primaryelectromagnetic induction coil 5 and theprimary resonance coil 6 are wound round a flat plate shapedprimary core 10 in a helical form. As a result, the primaryelectromagnetic induction coil 5 and theprimary resonance coil 6 are disposed on the same axis. Thesecondary resonance coil 7 and the secondaryelectromagnetic induction coil 9 are also wound round a flat plate shapedsecondary core 11 in a helical form. As a result, thesecondary resonance coil 7 and the secondaryelectromagnetic induction coil 9 are disposed on the same axis. - The
primary core 10 and thesecondary core 11 are disposed side by side to be parallel to each other. Therefore, an axis of each of the primaryelectromagnetic induction coil 5, theprimary resonance coil 6, thesecondary resonance coil 7, and the secondaryelectromagnetic induction coil 9 is disposed in a horizontal direction. The horizontal direction is a direction perpendicular to a direction in which theprimary coil unit 3 and thesecondary coil unit 4 are opposed to each other. - The above-described primary
electromagnetic induction coil 5 includes a coilmain body 51 and a wedge W in the same way as the first embodiment. The wedge W is mounted on theprimary core 10, which is a holding member. The wedge W is provided in an elongated form along a winding direction of the coilmain body 51. The wedge W is provided in a straight-line form along the winding direction. An inclined plane W1 is provided on the wedge W. The inclined plane W1 becomes higher as the position approaches a first end portion of the coilmain body 51. A line shaped accommodation groove W2 is provided on the inclined plane W1 to accommodate the end portion of the coilmain body 51. The end portion of the coilmain body 51 is accommodated in the line shaped accommodation groove W2. - In the modification illustrated in
FIG. 3 , a wedge W is provided in the secondaryelectromagnetic induction coil 9 as well to mount a first end portion of a coil main body 91 and separate the first end portion from other portions. In the modification illustrated inFIG. 3 as well, impedance matching can be achieved by moving the wedge W in the same way as the first embodiment and changing the number of turns of each of the coilmain bodies 51 and 91. - In the modification illustrated in
FIG. 3 , the wedges W are provided in both the primaryelectromagnetic induction coil 5 and the secondaryelectromagnetic induction coil 9. However, the present invention is not restricted to this. The wedge W may be provided only in the primaryelectromagnetic induction coil 5. Alternatively, the wedge W may be provided only in the secondaryelectromagnetic induction coil 9. - In the above-described first embodiment and the modifications thereof, each of the primary and secondary
electromagnetic induction coils FIG. 4 , the resonance coils 6 and 7 may include coil main bodies 61 and 71, respectively and the wedges W. In the example illustrated inFIG. 4 , the resonance coils 6 and 7 are formed in a spiral form. As illustrated inFIG. 5 , however, the wedges W may be provided in helical resonance coils 6 and 7. As illustrated inFIG. 6 , the wedges W may be provided in resonance coils 6 and 7 having axes disposed in the horizontal direction. - As a result, it is considered that the resonant frequency of the resonance coils 6 and 7 deviates due to not only the variation of the inter-coil distance D but also variations in manufacture of the resonance coils 6 and 7, the capacitors C1 and C2, ferrite and coil bobbins. However, it becomes possible to modify the resonant frequency by adjusting the position of the wedge W to adjust inductance of the resonance coils 6 and 7. As a result, impedance adjustment can be conducted.
- In the wedge W in the above-described first embodiment and modifications thereof, the inclined plane W1 and the line shaped accommodation groove W2 are provided. However, the present invention is not restricted to this. The inclined plane W1 and the line shaped accommodation groove W2 may not be provided.
- A power supply system 1 incorporating an electromagnetic induction coil according to the present invention in a second embodiment will now be described with reference to
FIG. 7 . The second embodiment differs from the first embodiment in configuration of the adjustment mechanism. Other portions are similar to those in the first embodiment illustrated inFIG. 1 . Therefore, detailed description of other portions will be omitted. In the first embodiment, the wedge W is provided as the adjustment mechanism. In the second embodiment, a turn back portion T provided by winding back a first end portion of a coilmain body 51 becomes the adjustment mechanism. - In the turn back portion T, magnetic fluxes generated from a portion along a winding direction and a portion along a wind back direction, which are adjacent to each other, cancel each other. Therefore, the turn back portion does not contribute to the function exhibited as a coil. If the turn back portion T is made large, therefore, the number of turns of the coil
main body 51 can be decreased. On the other hand, if the turn back portion T is made small, the number of turns of the coilmain body 51 can be increased. - In some cases, an inter-coil distance D is large due to, for example, an installation environment of the
primary coil unit 3 and thesecondary coil unit 4. In this case, the turn back portion T is made large to decrease the number of turns of the coilmain body 51, in the above-described power supply system 1. As a result, impedance matching can be achieved by decreasing the number of turns of the coilmain body 51, i.e., an inductance L and a mutual inductance M. On the other hand, in a case where the inter-coil distance D is small, the number of turns of the coilmain body 51 is increased by making the turn back portion T small. As a result, impedance matching can be achieved by increasing the number of turns of the coilmain body 51, i.e., the inductance L and the mutual inductance M to eliminate the bi-resonant characteristics. As a result, it is possible to conduct impedance adjustment and conduct non-contact power supply with high efficiency without relying upon a variable capacitor. Furthermore, the impedance can be adjusted simply by adjusting the length of the turn back portion T. - According to the above-described power supply system 1, the turn back portion T can be provided easily by providing the turn back portion T in the end portion of the coil
main body 51. - In the turn back portion T, magnetic fluxes generated from the portion along the winding direction and the portion along the wind back direction, which are adjacent to each other, cancel each other as described above. Therefore, the same effect can be obtained with a length that is equal to half of the mounting length of the wedge W.
- The present inventor actually measured the transmission efficiency as a function of the inter-coil distance with respect to a conventional article, which is a conventional power supply system having no turn back portion T, and a present invention article, which is the power supply system 1 according to the present invention having the turn back portion T. Results are illustrated in
FIG. 8 . As for the present invention article, the highest transmission efficiency is plotted by adjusting the length of the turn back portion T. - As illustrated in
FIG. 8 , the transmission efficiency of at least 90% can be kept in the conventional article only when the inter-coil distance D is in the range of 180 mm to 210 mm. On the other hand, in the present invention article, the transmission efficiency of at least 90% can be kept in a wide range of the inter-coil distance D of 180 mm to 250 mm. - The present inventor actually measured the power loss rate as a function of the inter-coil distance D with respect to the conventional article and the present invention article. Results are illustrated in
FIG. 9 . As for the present invention article, the lowest power loss rate is plotted by adjusting the length of the turn back portion T. As illustrated inFIG. 9 , in the conventional article, the power loss rate becomes large as the inter-coil distance D is separated from 200 mm. On the other hand, in the present invention article, the power loss rate can be made equal to 0% in a wide range of the inter-coil distance D of 180 mm to 250 mm. - In the above-described second embodiment, the turn back portion T is provided in the primary
electromagnetic induction coil 5 wound in the spiral form. However, the shape of a coil in which the turn back portion T can be provided is not restricted to this. The shape of the coil may be another well-known shape. For example, it is also conceivable to provide the turn back portion T in the primaryelectromagnetic induction coil 5 wound in a helical form as illustrated inFIG. 10 . Since theprimary resonance coil 6, thesecondary resonance coil 7, and the secondaryelectromagnetic induction coil 9 are similar to those inFIG. 2 , they are omitted fromFIG. 10 . - In the above-described second embodiment and the modification illustrated in
FIG. 10 , each of the primaryelectromagnetic induction coil 5, theprimary resonance coil 6, thesecondary resonance coil 7, and the secondaryelectromagnetic induction coil 9 is provided to have an axis in the vertical direction. However, disposition of the coils is not restricted to this. For example, it is also conceivable to provide the turn back portion T in the primaryelectromagnetic induction coil 5 that is wound round theprimary core 10 in a helical form coaxially with theprimary resonance coil 6 and that has an axis direction along the horizontal direction as illustrated inFIG. 11 . Since thesecondary resonance coil 7 and the secondaryelectromagnetic induction coil 9 are similar to those inFIG. 3 , they are omitted fromFIG. 11 . - In the above-described second embodiment, the turn back portion T is provided on the first end of the coil
main body 51. However, the present invention is not restricted to this. The turn back portion T may be provided on a second end of the coilmain body 51. The turn back portion T may be provided on both ends of the coilmain body 51. The turn back portion T is not restricted to end portions. For example, it is also conceivable to provide the turn back portion T in a central portion of the coilmain body 51. - In the above-described second embodiment, the turn back portion T is provided only in the primary
electromagnetic induction coil 5. However, the present invention is not restricted to this. The turn back portion T may be provided only in the secondaryelectromagnetic induction coil 9. It is also conceivable to provide the turn back portion T in both the primaryelectromagnetic induction coil 5 and the secondaryelectromagnetic induction coil 9. - In the above-described first and second embodiments, each of the coil
main bodies 51 and 91 has a plurality of turns (at least two turns). However, each of the coilmain bodies 51 and 91 may have one turn. - In the above-described second embodiment and modifications thereof, the turn back portion T is provided in the primary and secondary
electromagnetic induction coils FIG. 12 , the resonance coils 6 and 7 may include coil main bodies 61 and 71, respectively and the turn back portions T. In the example illustrated inFIG. 12 , the resonance coils 6 and 7 are formed in a spiral form. As illustrated inFIG. 13 , the turn back portions T may be provided in resonance coils 6 and 7 having an axis disposed in the horizontal direction. As illustrated inFIG. 14 , the turn back portions T may be provided in helical resonance coils 6 and 7. - It is considered that the resonant frequency of the resonance coils 6 and 7 deviates due to not only the variation of the inter-coil distance D but also variations in manufacture of the resonance coils 6 and 7, the capacitors C1 and C2, ferrite, and coil bobbins. However, it becomes possible to modify the resonant frequency by adjusting the position of the turn back portion T to adjust inductance of the resonance coils 5 and 6. As a result, impedance adjustment can be conducted.
- The above-described embodiments are nothing but representative forms of the present invention. The present invention is not restricted to the embodiments. In other words, the embodiments can be modified in various ways and executed without departing from the spirit of the present invention.
-
- 5 Primary electromagnetic induction coil (coil, electromagnetic induction coil)
- 6 Primary resonance coil (coil, resonance coil)
- 7 Secondary resonance coil (coil, resonance coil)
- 9 Secondary electromagnetic induction coil (coil, electromagnetic induction coil)
- 51 Coil main body
- 91 Coil main body
- W Wedge (adjustment mechanism, mounting portion)
- W1 Inclined plane
- T Turn back portion (adjustment mechanism)
Claims (2)
1. A coil serving as at least one coil among one pair of resonance coils that conduct non-contact power supply by magnetic field resonance, an electromagnetic induction coil that supplies power to a power supply side of the pair of resonance coils, or an electromagnetic induction coil supplied with power from a power receipt side of the pair of resonance coils, the coil comprising:
a coil main body; and
an adjustment mechanism configured to adjust a number of turns of the coil main body,
wherein the adjustment mechanism consists of a turn back portion provided by winding back a portion of the coil main body.
2. The coil according to claim 1 , wherein the turn back portion is provided on the end portion of the coil main body.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US15/956,237 US20180240585A1 (en) | 2013-02-19 | 2018-04-18 | Electromagnetic induction coil |
Applications Claiming Priority (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2013029763A JP6282398B2 (en) | 2013-02-19 | 2013-02-19 | Electromagnetic induction coil |
JP2013-029763 | 2013-02-19 | ||
PCT/JP2014/053749 WO2014129455A1 (en) | 2013-02-19 | 2014-02-18 | Electromagnetic induction coil |
US14/825,357 US9978494B2 (en) | 2013-02-19 | 2015-08-13 | Electromagnetic induction coil |
US15/956,237 US20180240585A1 (en) | 2013-02-19 | 2018-04-18 | Electromagnetic induction coil |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US14/825,357 Division US9978494B2 (en) | 2013-02-19 | 2015-08-13 | Electromagnetic induction coil |
Publications (1)
Publication Number | Publication Date |
---|---|
US20180240585A1 true US20180240585A1 (en) | 2018-08-23 |
Family
ID=51391245
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US14/825,357 Active 2034-03-31 US9978494B2 (en) | 2013-02-19 | 2015-08-13 | Electromagnetic induction coil |
US15/956,237 Abandoned US20180240585A1 (en) | 2013-02-19 | 2018-04-18 | Electromagnetic induction coil |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US14/825,357 Active 2034-03-31 US9978494B2 (en) | 2013-02-19 | 2015-08-13 | Electromagnetic induction coil |
Country Status (5)
Country | Link |
---|---|
US (2) | US9978494B2 (en) |
JP (1) | JP6282398B2 (en) |
CN (1) | CN105074850A (en) |
DE (1) | DE112014000885T5 (en) |
WO (1) | WO2014129455A1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20160094074A1 (en) * | 2013-10-23 | 2016-03-31 | Apple Inc. | Method and Apparatus for Inductive Power Transfer |
US10404235B2 (en) | 2013-11-21 | 2019-09-03 | Apple Inc. | Using pulsed biases to represent DC bias for charging |
US10601250B1 (en) | 2016-09-22 | 2020-03-24 | Apple Inc. | Asymmetric duty control of a half bridge power converter |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105515210A (en) * | 2014-09-26 | 2016-04-20 | 国家电网公司 | Non-contact charging pile, on-board charging device, and charging system |
JP6252433B2 (en) * | 2014-10-28 | 2017-12-27 | トヨタ自動車株式会社 | Non-contact power transmission / reception system |
JP6582463B2 (en) * | 2015-03-17 | 2019-10-02 | 株式会社村田製作所 | Wire wound chip transformer and distributor |
JP2016225577A (en) * | 2015-06-03 | 2016-12-28 | 船井電機株式会社 | Power supply device and power reception device |
US10122217B2 (en) * | 2015-09-28 | 2018-11-06 | Apple Inc. | In-band signaling within wireless power transfer systems |
JP6453787B2 (en) | 2016-02-04 | 2019-01-16 | 矢崎総業株式会社 | Winding unit |
DE202016007184U1 (en) * | 2016-11-22 | 2016-12-02 | Stadlbauer Marketing + Vertrieb Gmbh | Coil assembly and model car with such a coil arrangement |
WO2019168770A1 (en) | 2018-02-28 | 2019-09-06 | Massachusetts Institute Of Technology | Coreless power transformer |
JP7439385B2 (en) | 2019-03-22 | 2024-02-28 | オムロン株式会社 | Contactless power supply device |
CN110112835A (en) * | 2019-05-16 | 2019-08-09 | 中南大学 | Four loop construction magnet coupled resonant type wireless energy transmission system of frequency reconfigurable |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS61149303A (en) * | 1984-12-24 | 1986-07-08 | 松下電工株式会社 | Method of bonding sheet-shaped material |
JPS61149303U (en) * | 1985-03-08 | 1986-09-16 | ||
US20100244583A1 (en) * | 2009-03-31 | 2010-09-30 | Fujitsu Limited | Wireless power apparatus and wireless power-receiving method |
US20100320963A1 (en) * | 2002-05-13 | 2010-12-23 | Access Business Group International Llc | Contact-less power transfer |
JP2011135717A (en) * | 2009-12-25 | 2011-07-07 | Toko Inc | Wireless power transmission system |
US20120228956A1 (en) * | 2011-03-10 | 2012-09-13 | Semiconductor Energy Laboratory Co., Ltd. | Power-receiving device, wireless power-feeding system including power-receiving device, and wireless communication system including power-receiving device |
US20120286584A1 (en) * | 2009-11-04 | 2012-11-15 | Korea Electrotechnology Research Institute | Space-adaptive wireless power transfer system and method using evanescent field resonance |
US20130093258A1 (en) * | 2011-10-18 | 2013-04-18 | Lg Innotek Co., Ltd. | Electronic device and wireless power receiver equipped in the same |
Family Cites Families (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0242705A (en) * | 1988-08-01 | 1990-02-13 | Matsushita Electric Ind Co Ltd | Variable coil |
JPH0272522U (en) * | 1988-11-22 | 1990-06-01 | ||
US4980663A (en) * | 1989-12-28 | 1990-12-25 | Ford Motor Company | Automated adjustment of air-core coil inductance |
US6184755B1 (en) | 1999-07-16 | 2001-02-06 | Lucent Technologies, Inc. | Article comprising a variable inductor |
US7825543B2 (en) | 2005-07-12 | 2010-11-02 | Massachusetts Institute Of Technology | Wireless energy transfer |
JP4921466B2 (en) | 2005-07-12 | 2012-04-25 | マサチューセッツ インスティテュート オブ テクノロジー | Wireless non-radiative energy transfer |
JP5049018B2 (en) * | 2007-01-09 | 2012-10-17 | ソニーモバイルコミュニケーションズ株式会社 | Non-contact charger |
JP4911148B2 (en) * | 2008-09-02 | 2012-04-04 | ソニー株式会社 | Contactless power supply |
US8947186B2 (en) * | 2008-09-27 | 2015-02-03 | Witricity Corporation | Wireless energy transfer resonator thermal management |
JP5810291B2 (en) * | 2010-03-30 | 2015-11-11 | パナソニックIpマネジメント株式会社 | Wireless power transmission system |
JP2012023298A (en) * | 2010-07-16 | 2012-02-02 | Equos Research Co Ltd | Resonance coil |
JP2012023299A (en) * | 2010-07-16 | 2012-02-02 | Equos Research Co Ltd | Resonance coil |
JP5562804B2 (en) * | 2010-11-02 | 2014-07-30 | 昭和飛行機工業株式会社 | Non-contact power feeding device with variable inductance |
CN103270671B (en) * | 2010-12-21 | 2016-02-24 | 矢崎总业株式会社 | Feeding power system |
CN102437656B (en) * | 2011-12-22 | 2014-07-23 | 重庆大学 | Wireless energy transmission system based on magnetic resonance array |
WO2014125596A1 (en) * | 2013-02-14 | 2014-08-21 | トヨタ自動車株式会社 | Power reception apparatus and power transmission apparatus |
-
2013
- 2013-02-19 JP JP2013029763A patent/JP6282398B2/en active Active
-
2014
- 2014-02-18 WO PCT/JP2014/053749 patent/WO2014129455A1/en active Application Filing
- 2014-02-18 DE DE112014000885.0T patent/DE112014000885T5/en not_active Withdrawn
- 2014-02-18 CN CN201480009509.0A patent/CN105074850A/en active Pending
-
2015
- 2015-08-13 US US14/825,357 patent/US9978494B2/en active Active
-
2018
- 2018-04-18 US US15/956,237 patent/US20180240585A1/en not_active Abandoned
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS61149303A (en) * | 1984-12-24 | 1986-07-08 | 松下電工株式会社 | Method of bonding sheet-shaped material |
JPS61149303U (en) * | 1985-03-08 | 1986-09-16 | ||
US20100320963A1 (en) * | 2002-05-13 | 2010-12-23 | Access Business Group International Llc | Contact-less power transfer |
US20100244583A1 (en) * | 2009-03-31 | 2010-09-30 | Fujitsu Limited | Wireless power apparatus and wireless power-receiving method |
US20120286584A1 (en) * | 2009-11-04 | 2012-11-15 | Korea Electrotechnology Research Institute | Space-adaptive wireless power transfer system and method using evanescent field resonance |
JP2011135717A (en) * | 2009-12-25 | 2011-07-07 | Toko Inc | Wireless power transmission system |
US20120228956A1 (en) * | 2011-03-10 | 2012-09-13 | Semiconductor Energy Laboratory Co., Ltd. | Power-receiving device, wireless power-feeding system including power-receiving device, and wireless communication system including power-receiving device |
US20130093258A1 (en) * | 2011-10-18 | 2013-04-18 | Lg Innotek Co., Ltd. | Electronic device and wireless power receiver equipped in the same |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20160094074A1 (en) * | 2013-10-23 | 2016-03-31 | Apple Inc. | Method and Apparatus for Inductive Power Transfer |
US10404235B2 (en) | 2013-11-21 | 2019-09-03 | Apple Inc. | Using pulsed biases to represent DC bias for charging |
US10601250B1 (en) | 2016-09-22 | 2020-03-24 | Apple Inc. | Asymmetric duty control of a half bridge power converter |
Also Published As
Publication number | Publication date |
---|---|
WO2014129455A1 (en) | 2014-08-28 |
CN105074850A (en) | 2015-11-18 |
US9978494B2 (en) | 2018-05-22 |
US20150348692A1 (en) | 2015-12-03 |
JP2014160702A (en) | 2014-09-04 |
JP6282398B2 (en) | 2018-02-21 |
DE112014000885T5 (en) | 2015-11-05 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US9978494B2 (en) | Electromagnetic induction coil | |
JP7194091B2 (en) | Inductive power transfer device | |
US10158256B2 (en) | Contactless connector system tolerant of position displacement between transmitter coil and receiver coil and having high transmission efficiency | |
WO2011122249A1 (en) | Contactless power feeding apparatus and contactless power feeding method | |
US9457676B2 (en) | Contactless power transfer apparatus | |
JP6546371B2 (en) | Coil unit and non-contact power feeding device | |
WO2013002240A1 (en) | Power feeding system design method and power feeding system | |
JP5889250B2 (en) | Power transmission device, power transmission device and power reception device for power transmission device | |
JP6305728B2 (en) | Coil unit and power transmission system | |
WO2014142068A1 (en) | Power feeding-side coil and non-contact power feeding device | |
US20150188364A1 (en) | Wireless power receiving apparatus and wireless power transmitting apparatus | |
US11139096B2 (en) | Common mode choke coil and wireless charging circuit | |
WO2014136737A1 (en) | Power supplying unit, power receiving unit, and power supplying system | |
WO2013145573A1 (en) | Contactless power supply system and contactless power supply method | |
US9893566B2 (en) | Power supply system | |
WO2013002241A1 (en) | Electrical supply system | |
JP6103527B2 (en) | Surplus length absorber and coil unit | |
JP5960973B2 (en) | Transmission antenna for power transmission, power transmission device, and non-contact power transmission device | |
US20140054972A1 (en) | Wireless power transmission system | |
WO2020122017A1 (en) | Power receiving device | |
JP2013027251A (en) | Power supply system | |
JP2013021862A (en) | Power feeding system design method | |
JP2016164975A (en) | Coil unit, wireless power supply device, wireless power reception device and wireless power transmission device | |
JP2013089872A (en) | Power feeding system |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STPP | Information on status: patent application and granting procedure in general |
Free format text: RESPONSE TO NON-FINAL OFFICE ACTION ENTERED AND FORWARDED TO EXAMINER |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: FINAL REJECTION MAILED |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |