JP6600607B2 - Inductor unit, wireless power transmission device, electric vehicle, and charging facility - Google Patents

Description

  Embodiments described herein relate generally to an inductor unit, a wireless power transmission device, an electric vehicle, and a charging facility.

  In a wireless power transmission apparatus that performs power transmission in a non-contact manner, an inductor unit including a plurality of inductors is used to increase the power that can be transmitted. In recent years, an inductor unit that can suppress interference coupling between inductors in an inductor unit, which is a cause of a decrease in transmission efficiency, has appeared and is used in wireless power transmission devices, electric vehicles, and the like.

  The inductor unit mainly arranges inductors that wirelessly transmit power in parallel, and reduces radiated emissions by the anti-phase effect. However, even if it does in this way, if the electric power transmitted by radio | wireless is enlarged, there exists a subject that a radiation emission will exceed an allowable value.

International Publication No. 2015/189976

  One embodiment of the present invention provides an inductor unit that reduces interference coupling between inductors.

  An inductor unit according to an embodiment of the present invention includes a core and a winding wound around the core, the first and second inductors in which the axial direction of the winding is substantially parallel, and the axial direction of the winding is , And third and fourth inductors that are substantially perpendicular to the axial direction of the windings of the first and second inductors. In plan view, the first line segment connecting the center of the core of the first inductor and the center of the core of the second inductor is neither parallel nor perpendicular to the axial direction of the winding of the first inductor. And the second line segment connecting the center of the core of the third inductor and the center of the core of the fourth inductor is the winding of the third inductor. The third and fourth inductors are arranged so that they are neither parallel nor perpendicular to the axial direction.

The figure which shows an example of schematic structure of the inductor unit which concerns on 1st Embodiment. The figure which shows an example of a core. The figure which shows an example of a coil | winding. The figure which shows another example of schematic structure of the inductor unit which concerns on 1st Embodiment. The figure which shows an example of the size ratio of an inductor. The figure which shows another example of the size ratio of an inductor. The figure which shows an example in case there are three pairs of inductors. The figure which shows another example in case there are three pairs of inductors. The figure which shows an example in case there are four pairs of inductors. The block diagram which shows an example of schematic structure of the wireless power transmission apparatus which concerns on 2nd Embodiment. The figure which shows an example of the charging facility using the inductor unit by which the inductor is arrange | positioned at point symmetry.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a diagram illustrating an example of a schematic configuration of an inductor unit according to the first embodiment. FIG. 1 is a plan view of the inductor unit. The inductor unit 100 according to this embodiment includes at least four inductors 1. Note that four or more inductors 1 may be provided.

  In the present description, each inductor 1 is distinguished by an alphabet of symbols. In the example of FIG. 1, the inductor unit 100 includes an inductor 1a, an inductor 1b, an inductor 1c, and an inductor 1d. Further, in the following description, what is determined for each inductor 1 is also distinguished from which one of the inductors 1 is determined using an alphabetical suffix.

  The inductor unit 100 is used as a part of a resonance circuit for power transmission or power reception of the wireless power transmission device. Wireless power transmission is performed using at least one inductor 1 of the inductor unit 100. Specifically, the inductor 1 of the inductor unit 100 is coupled to another inductor that is a power transmission counterpart arranged oppositely by electromagnetic induction or magnetic field resonance (resonance). The other inductor is not the inductor 1 included in the inductor unit 100. Thereby, wireless power transmission is performed.

  In this description, the term power transmission includes power transmission and power reception.

  The inductor 1 is a solenoid type inductor. The inductor 1 includes a core 11, a winding 12, and a housing 13. In FIG. 1, the core 11 is black, the winding 12 is gray, and the housing 13 is white.

  The core 11 is formed of a magnetic material such as ferrite. In addition, when the magnetic body with which the inductor 1 is comprised is comprised from the several member, when the magnetic body is not a rectangle etc., the virtual rectangle which the outer periphery of a magnetic body fits is defined as the core 11. FIG. FIG. 2 is a diagram illustrating an example of a core. In the example of FIG. 2, the inductor 1 includes two magnetic bodies 14. In the case as shown in FIG. 2, a virtual rectangle in which the outer peripheries of the two magnetic bodies 14 are accommodated, as indicated by broken lines, becomes the core 11. The same applies when the magnetic body 14 is not rectangular.

  The winding 12 is an insulated wire wound around the core 11. The winding 12 may be, for example, a copper wire, an aluminum wire, or a litz wire. FIG. 3 is a diagram illustrating an example of a winding. FIG. 3 is an image view of a cross section passing through the center of the inductor 1 and parallel to the axial direction of the winding 12. In FIG. 3, a dielectric bobbin 15 exists between the core 11 and the winding 12. In this manner, the winding 12 may be wound around the core 11 via the dielectric bobbin 15. When a current flows through the winding 12, a magnetic field is generated in the core 11.

  The housing 13 is a dielectric formed so as to cover the entire core 11 and the winding 12. In FIG. 1, for the sake of convenience, only the outer shape of the housing 13 is shown, and the core 11 and the winding 12 are exposed on the surface. However, the housing 13 is actually the entire core 11 and the winding 12. It is formed so as to cover. Each inductor 1 does not have to include the housing 13. For example, the inductor unit 100 may be covered with one housing 13.

  The inductor 1 may be connected to a compensation capacitor that is a capacitor for compensating for leakage inductance. When the leakage inductance of the inductor 1 is small, the inductor 1 may not be connected to the compensation capacitor. The connection method between the inductor 1 and the compensation capacitor may be parallel or series. Note that the compensation capacitor may be connected to a circuit different from the inductor unit 100.

  Next, directions for explaining the arrangement relationship of the inductor 1 will be described. The arrangement to be described is the arrangement shown in FIG. 1, that is, the arrangement in plan view. Therefore, the direction is also a direction in plan view.

  The direction of the magnetic field generated in the core 11 when a current flows through the winding 12 is referred to as a magnetic flux direction A. The magnetic flux direction A coincides with the axial direction of the winding 12. The direction perpendicular to the magnetic flux direction A coincides with the radial direction of the winding 12.

  The center of the core 11 in plan view is referred to as a center CP. A straight line passing through the center CP and parallel to the axial direction of the winding 12 is referred to as a first center line CL1. In the case of the example in FIG. 1, the first center line CL1a of the inductor 1a passes through the middle points of the upper side and the lower side of the core 11a and is parallel to the magnetic flux direction A.

  A straight line passing through the center CP and parallel to the radial direction of the winding 12 is referred to as a second center line CL2. In the case of the example in FIG. 1, the second center line CL2a of the inductor 1a passes through the middle points of the right side and the left side of the core 11a and is perpendicular to the magnetic flux direction A. The intersection of the first center line CL1 and the second center line CL2 is the center CP.

  Next, the arrangement relationship between the inductor 1a and the inductor 1b will be described. In addition, although it assumes that each inductor 1 exists on the same horizontal surface, it does not need to exist on the same horizontal surface. That is, the position of each inductor 1 in the vertical direction may be the same or different.

  The inductor 1a and the inductor 1b are arranged such that the first center line CL1a of the inductor 1a and the first center line CL1b of the inductor 1b are substantially parallel. That is, the magnetic flux direction Aa of the inductor 1a and the magnetic flux direction Ab of the inductor 1b are substantially parallel. That is, it can be said that the axial direction and the radial direction of the windings 12 of the inductor 1a and the inductor 1b are substantially parallel.

  Further, the inductor 1a and the inductor 1b are arranged so that the line segment connecting the center CPa of the inductor 1a and the center CPb of the inductor 1b is not substantially parallel or substantially perpendicular to the windings 12 of the inductor 1a and the inductor 1b. . The line segment is referred to as LS1. In other words, when the angle formed by the line segment LS1 and the first center line CL1a of the inductor 1a is referred to as an angle φ1, the inductor 1a and the inductor 1b have an angle φ1 larger than 0 degree and smaller than 90 degrees. It can be said that they are arranged as follows. The angle φ1 is an acute angle of two angles sandwiched between the line segment LS1 and the first center line CL1a.

  It is known from Prior Art Document 1 that when the inductor 1a and the inductor 1b are arranged as described above, the absolute value of the coupling coefficient between the inductor 1a and the inductor 1b can be reduced by adjusting the angle φ1. It has been.

  In particular, there exists an angle at which the coupling coefficient of the inductor 1a and the inductor 1b is 0 in the range where the angle φ1 is not less than 50 degrees and not more than 70 degrees. For this reason, the inductor 1a and the inductor 1b are preferably arranged such that the angle φ1 is not less than 50 degrees and not more than 70 degrees. With such an arrangement, the absolute value of the coupling coefficient between the inductor 1a and the inductor 1b can be reduced more effectively.

  Next, the arrangement relationship between the inductor 1c and the inductor 1d will be described. The inductor 1c and the inductor 1d are arranged such that the first center line CL1c of the inductor 1c and the first center line CL1d of the inductor 1d are substantially parallel. That is, the magnetic flux direction Ac of the inductor 1c and the magnetic flux direction Ad of the inductor 1d are substantially parallel. That is, it can be said that the axial direction and the radial direction of the winding 12 of the inductor 1c and the inductor 1d are substantially parallel.

  Further, the inductor 1c and the inductor 1d are arranged so that the line segment connecting the center CPc of the inductor 1c and the center CPd of the inductor 1d is not substantially parallel or substantially perpendicular to the winding 12 of the inductors 1c and 1d. . The line segment is referred to as LS2. In other words, when the angle formed by the line LS2 and the first center line CL1c of the inductor 1c is referred to as an angle φ2, the inductor 1c and the inductor 1d have an angle φ2 larger than 0 degree and smaller than 90 degrees. It can be said that they are arranged as follows. The angle φ2 is an acute angle of two angles sandwiched between the line segment LS2 and the first center line CL1a.

  When the inductor 1c and the inductor 1d are arranged as described above, the absolute value of the coupling coefficient between the inductor 1c and the inductor 1d can be reduced by adjusting the angle φ2.

  In particular, there is an angle at which the coupling coefficient of the inductor 1c and the inductor 1d becomes 0 when the angle φ2 is in the range of 50 degrees to 70 degrees. For this reason, the inductor 1c and the inductor 1d are preferably arranged so that the angle φ2 is not less than 50 degrees and not more than 70 degrees. With such an arrangement, the absolute value of the coupling coefficient between the inductor 1c and the inductor 1d can be reduced more effectively.

  As described above, the four inductors 1 of the inductor unit 100 include two combinations of the inductor 1a and the inductor 1b in which the winding 12 is substantially parallel and the combination of the inductor 1c and the inductor 1d in which the winding 12 is substantially parallel. Have one combination. In each pair, the line connecting the center of the core 11 of one inductor 1 and the center of the core 11 of the other inductor 1 is both parallel and perpendicular to the axial direction of the winding 12 of the one inductor 1. Each inductor 1 is arranged so that it does not become.

  Moreover, the absolute value of the coupling coefficient of each pair can be reduced by arranging each inductor 1 so that the angle φ1 and the angle φ2 are in the range of 50 degrees to 70 degrees. It should be noted that either the angle φ1 or the angle φ2 may be set to be in the range of 50 degrees or more and 70 degrees or less.

  Next, the arrangement relationship between the combination of the inductor 1a and the inductor 1b and the combination of the inductor 1c and the inductor 1d will be described. A combination of the inductor 1a and the inductor 1b is referred to as a pair 1. A combination of the inductor 1c and the inductor 1d is referred to as a pair 2.

  The pair 1 and the pair 2 are arranged so that the axial direction of the winding 12 of the inductor 1 in the pair 1 and the axial direction of the winding 12 of the inductor 1 in the pair 2 are substantially perpendicular. That is, the magnetic flux direction Aa of the inductor 1a is substantially perpendicular to the magnetic flux direction Ac of the inductor 1c and the magnetic flux direction Ad of the inductor 1d. Similarly, the magnetic flux direction Ab of the inductor 1b is substantially perpendicular to the magnetic flux direction Ac of the inductor 1c and the magnetic flux direction Ad of the inductor 1d.

  When the two magnetic flux directions A are substantially perpendicular, the absolute value of the coupling coefficient between the inductors 1 that generate magnetic flux is small. Therefore, the inductor 1a has a smaller absolute value of the coupling coefficient than the inductors 1c and 1d. The inductor 1b has a smaller absolute value of the coupling coefficient than the inductors 1c and 1d. Further, as described above, the inductor 1a and the inductor 1b are arranged so that the absolute value of the coupling coefficient is small.

  Therefore, with the above arrangement, the absolute value of the coupling coefficient between one inductor 1 in the inductor unit 100 and all other inductors 1 in the inductor unit 100 can be reduced. Therefore, in the wireless power transmission system using the inductor unit 100, the interference of each system (inductor) can be reduced.

  Further, the two inductors 1 whose winding axial directions are substantially perpendicular to each other are arranged so that the first center line CL1 of one inductor 1 and the second center line CL2 of the other inductor 1 coincide with each other. In this case, the absolute value of the coupling coefficient between the two inductors 1 is smaller than in other arrangements. This arrangement is referred to as the same center line arrangement.

  For example, in FIG. 1, the first center line CL1a of the inductor 1a matches the second center line CL2d of the inductor 1d. That is, the inductor 1a and the inductor 1d have the same center line arrangement. Therefore, the absolute value of the coupling coefficient between the inductor 1a and the inductor 1d is smaller than when the inductor 1a and the inductor 1d are not arranged in the same center line.

  Therefore, as shown in FIG. 1, the first center line CL1 of each inductor 1 in the inductor unit 100 is arranged so as to coincide with the second center line CL2 of another inductor 1 in which the axial direction of the winding is substantially vertical. In such a case, the interference of each system (inductor) becomes even smaller than in other arrangements.

  In the example of FIG. 1, in all four inductors 1, the first center line CL <b> 1 coincides with the second center line CL <b> 2 of the other inductor 1 whose winding axial direction is substantially vertical. It is not necessary for all 100 inductors 1 to have the same centerline arrangement. If at least one inductor 1 of the inductor unit 100 is arranged in the same center line, the interference is smaller than when all the inductors 1 in the inductor unit 100 are not arranged in the same center line.

  The arrangement of the pair 1 and the pair 2 is not limited to the example of FIG. 1 as long as the axial direction of the winding 12 is arranged to be vertical. FIG. 4 is a diagram illustrating another example of the schematic configuration of the inductor unit according to the first embodiment.

  In the example of FIG. 1, the line segment LS1 and the line segment LS2 intersect. In the example of FIG. 4, the line segment LS1 and the line segment LS2 do not intersect. Thus, for a certain pair, if the axial direction of the other pair of windings 12 is vertical, the positional relationship of the other pair may be determined arbitrarily.

  Next, the size of the inductor 1 will be described. The sizes of the inductors 1 may all be the same, some may be the same, or may be different.

  The dimension (size) of the core 11 in the axial direction of the winding 12 is referred to as a core length (depth) L11. The dimension of the core 11 in the radial direction of the winding 12 is referred to as a core width W11. The lengths of the core length L11 and the core width W11 are not particularly limited, and may be arbitrarily determined.

  Note that the core length L11 when the virtual rectangular shape is defined as the core 11 matches the maximum dimension in the axial direction of the winding 12 of the magnetic body 14. Further, the core width W11 in this case coincides with the maximum dimension in the radial direction of the winding 12 of the magnetic body 14.

  The dimension of the winding 12 in the axial direction of the winding 12 is referred to as a winding length L12. The winding length L12 may be arbitrarily determined.

  However, the size of the inductor 1 affects the power that can be transmitted by the inductor 1. Therefore, if other factors that affect the transmittable power, such as current, are the same, the transmittable power of the inductor 1 increases as the size of the inductor 1 increases. Further, the coupling coefficient also changes depending on the size ratio of the inductor 1.

  FIG. 5 is a diagram illustrating an example of the size ratio of the inductor 1. In the example of FIG. 5, the sizes of the inductor 1a and the inductor 1b are smaller than the sizes of the inductor 1c and the inductor 1d. If the other factors affecting the transmittable power are the same, in the case of FIG. 5, the transmittable power of the inductor 1a and the inductor 1b is smaller than the transmittable power of the inductor 1c and the inductor 1d. Thus, if there are inductors 1 of different sizes, when power transmission is performed without using all of the inductors 1, unnecessary power consumption can be achieved by the user or the like selecting an inductor to be used for transmission according to the required power. Can be suppressed. Although the coupling coefficient changes, the sizes of the inductors 1 in the pair 1 or the pair 2 may be different.

  FIG. 6 is a diagram illustrating another example of the size ratio of the inductor. In the example of FIG. 6, the aspect ratio of the inductor 1a and the inductor 1b (ratio of the core length L11 and the core width W11) is different from the aspect ratio of the inductor 1c and the inductor 1d. Specifically, the core length L11 of the core 11 included in the inductor 1a and the inductor 1b is longer than the core length L11 of the core 11 included in the inductor 1c and the inductor 1d.

  The power transmission efficiency is good when the positions of the power transmission counterparts are the same in plan view, that is, when they overlap. When the overlap is deviated, the degree of decrease in the efficiency of power transmission differs depending on which direction is shifted.

  When the position of the power transmission counterpart is shifted in the axial direction (magnetic flux direction A) of the winding 12 of the inductor 1, the power transmission efficiency is higher than when the position of the power transmission counterpart is shifted in the radial direction of the winding 12 of the inductor 1. The degree of decrease is high. When the difference between the position of the power transmission partner and the position of the inductor 1 is referred to as displacement, the axial direction of the winding 12 of the inductor 1 has a small allowable range of displacement and the radial direction of the winding 12 of the inductor 1. It can be said that the allowable range of displacement is large.

  However, although the allowable range of misalignment is small in the axial direction of the winding 12 of the inductor 1, the degree of reduction in power transmission efficiency can be reduced by increasing the core length L11. Therefore, in the example of FIG. 6, even if the position of the power transmission partner of the inductor 1a is shifted in the axial direction of the winding 12a of the inductor 1a, the degree of decrease in power transmission efficiency is small compared to the example of FIG. .

  As described above, the core length L11 of the core 11 included in the inductor 1 of the pair 1 may be different from the core length L11 of the core 11 included in the inductor 1 of the pair 2. For example, when a wireless power transmission device including the inductor unit 100 as shown in FIG. 6 is used in a charging parking lot, the allowable range of the parking position of the electric vehicle can be expanded. In the case of FIG. 6, even if the electric vehicle is parked in the axial direction of the winding 12a, the degree of reduction in the efficiency of power transmission can be suppressed. In this way, when a direction in which the positional deviation from the power transmission partner increases can be predicted, the core length L11 parallel to the direction may be increased in advance. Although the coupling coefficient changes, the core lengths L11 of the inductors 1 in the pair 1 or pair 2 may be different.

  Next, the transmission power of the inductor will be described. The transmission power of the inductors 1 of the pair 1 and the pair 2 may be the same or different. The transmission power is increased or decreased depending on the size of the core 11, the current flowing through the winding 12, and the like. Although the coupling coefficient changes, the transmission power between the inductors 1 in the pair 1 or the pair 2 may be different.

  Further, in each pair, since the two inductors 1 are substantially parallel in the radial direction of the winding 12, the magnetic fields generated by the windings 12 of the two inductors 1 can be reversed in phase. By making the magnetic field out of phase, the radiated emissions of the inductors 1 cancel each other, and the effect of reducing the radiated emission (reverse phase effect) can be obtained. Note that either one or both of pair 1 and pair 2 may be reversed.

  To reverse the magnetic fields generated by the windings 12 of the two inductors 1 in the pair, the windings 12 of the two inductors 1 flow in the windings 12 of the two inductors 1 when the winding directions are the same. The current may be reversed. When the winding directions of the windings 12 of the two inductors 1 are different, the currents flowing through the windings 12 of the two inductors 1 may be set in the same direction.

  In addition, since the reduction effect of the radiated emission by the reverse phase effect is finite, the radiated emission may not be less than the reference value when it is desired to increase the transmission power. By disposing the four inductors 1 as in the present embodiment and transmitting the power in two opposite phases, the radiated emissions are distributed in a polarization manner, and the radiated emissions can be reduced. When four inductors 1 are used, interference becomes a problem. However, interference can be suppressed by arranging the four inductors 1 as in this embodiment.

  The antiphase effect also occurs for higher harmonics other than the fundamental wave component of the current. Whether or not there is a cancellation effect for even, odd or both higher harmonics is based on a method of reversing the current component of the fundamental wave. As a method of making the current reverse, there are a method of switching the terminals of the coil, a method of shifting the timing of the output waveform by 180 degrees using an inverter, and the like.

  The inductors 1 in each pair may be connected by the same inverter or may be connected by different inverters. The connection method with the inverter may be serial or parallel. Even when the inductor 1 is connected to the compensation capacitor, the circuits including the inductor 1 and the compensation capacitor may be connected by the same inverter or may be connected by separate inverters. Further, in connection with the inverter, a filter may be connected between the inverter. When a low-order filter is connected, it is possible to obtain an effect of reducing radiated emissions even for high-order harmonics, and radiated emissions can be suppressed within a predetermined allowable value.

  Further, if the frequency f1 of the high-frequency current flowing in the inductor 1 of the pair 1 and the frequency f2 of the high-frequency current flowing in the inductor 1 of the pair 2 are different, the respective radiated emissions are not added together. Thereby, radiation emission can be lowered. In addition, the case where the frequency f1 and the frequency f2 are 200 Hz or more apart is still more preferable. Since the resolution for measuring the radiated emission is 200 Hz, the radiated emission can be lowered due to the frequency dispersion effect.

  However, if the frequency f1 and the frequency f2 are too far apart, a problem may occur. For example, when the inductor unit 100 is used in a power transmission device using the 85 kHz band, the frequencies f1 and f2 must be 81 kHz to 90 kHz, so the frequency f1 and the frequency f2 are set so as not to be separated from 9 kHz. .

  Moreover, although the case where there exist two pairs was introduced in this embodiment, three or more pairs may exist. The arrangement of inductors 1 of other pairs that are neither pair 1 nor pair 2 is the same as that of pair 1 and pair 2.

  FIG. 7 to FIG. 9 show examples when there are three or more pairs. FIG. 7 is a diagram illustrating an example in which there are three pairs of inductors 1. FIG. 8 is a diagram illustrating another example in which there are three inductor pairs. 7 and 8, the inductor 100 shown in FIG. 1 further includes two inductors 1 (inductor 1e and inductor 1f).

  In the example of FIG. 1, the pair 1 is assumed to be an inductor 1a and an inductor 1b, and the pair 2 is assumed to be an inductor 1c and an inductor 1d. In FIG. 7 and FIG. 8, as in FIG. 1, it may be considered that there is a pair 1 consisting of an inductor 1a and an inductor 1b and a pair 2 consisting of an inductor 1c and an inductor 1d. Alternatively, as indicated by dotted frames f1, f2, and f3 in FIGS. 7 and 8, the pair 1 including the inductor 1a and the inductor 1e, the pair 2 including the inductor 1c and the inductor 1d, and the inductor 1b and the inductor 1f You may think that there is a pair 3 consisting of: Even if there are three pairs, the inductors 1 in each pair may be arranged so that the absolute value of the coupling coefficient becomes small as described above.

  7 and 8, the inductor 1e and the inductor 1f have the first center line CL1 that coincides with the second center line CL2 of the other inductor 1 in which the axial direction of the winding is substantially vertical, or The two center lines CL2 are arranged so as to coincide with the first center line CL1 of another inductor 1 in which the axial direction of the winding is substantially vertical. Specifically, in the inductor 1e, the first center line CL1e coincides with the second center line CL2c of the inductor 1c in which the axial direction of the winding is substantially vertical. In the inductor 1f, the second center line CL2f coincides with the first center line CL1c of the inductor 1c in which the axial direction of the winding is substantially vertical. By arranging the added inductor 1 as described above, the interference of each system (inductor) can be further reduced.

  FIG. 9 is a diagram illustrating an example in which there are four inductor pairs. In FIG. 9, the inductor 100 shown in FIG. 1 further includes four inductors 1 (inductor 1e, inductor 1f, inductor 1g, and inductor 1h). The configuration in FIG. 9 is the same as the configuration in which two inductor units 100 shown in FIG. 1 are arranged.

  In the example of FIG. 9, in each inductor 1, the first center line CL <b> 1 matches the second center line CL <b> 2 of the other two inductors 1 in which the axial direction of the winding is substantially vertical, or the second center line CL2 is arranged such that the axial direction of the winding coincides with the first center line CL1 of the other two inductors 1 that are substantially perpendicular. For example, in the inductor 1a, the first center line CL1a includes the second center line CL2d of the inductor 1d in which the winding axial direction is substantially vertical and the second center line CL2h of the inductor 1h in which the winding axial direction is substantially vertical. Matches. By arranging in this way, the number of systems that can suppress interference can be increased.

  As described above, according to the first embodiment, each of the four inductors of the inductor unit 100 can reduce the absolute value of the coupling coefficient with all the other inductors of the inductor unit 100. Therefore, in the wireless power transmission system using the inductor unit 100, the interference of each system (inductor) can be reduced.

(Second Embodiment)
As a second embodiment, a wireless power transmission device including the inductor unit 100 of the first embodiment will be described. FIG. 10 is a block diagram illustrating an example of a schematic configuration of the wireless power transmission device according to the second embodiment. A wireless power transmission device 200 for power transmission and a wireless power transmission device 300 for power reception are shown.

  In the example of FIG. 10, the wireless power transmission device 200 for power transmission is installed in a charging parking lot. A power receiving wireless power transmission device 300 is installed in an electric vehicle 400. The charging parking lot is a charging facility that charges the electric vehicle 400 using the wireless power transmission device 200. FIG. 10 is an example, and the installation locations of the wireless power transmission device 200 and the wireless power transmission device 300 are not limited to the charging parking lot and the electric vehicle. In FIG. 10, the wireless power transmission device 200 is installed on the ground, and the wireless power transmission device 300 is installed on the bottom of the electric vehicle 400, but is not limited thereto. For example, the wireless power transmission device 200 may be installed on the ceiling of a building such as a tunnel, and the wireless power transmission device 300 may be installed on the top of the electric vehicle 400. Further, a charging stand or the like provided with the wireless power transmission device 200 on the side may charge the electric vehicle 400 provided with the wireless power transmission device 300 on the side.

  The wireless power transmission device 200 includes a high frequency power source 201, a filter 202, and an inductor unit 203. The inductor unit 203 is used for power transmission.

  The wireless power transmission device 300 included in the electric vehicle 400 includes an inductor unit 301, a filter 302, a rectifier 303, a DC / DC converter 304, and a storage battery 305. The inductor unit 301 is used for power reception.

  The inductor unit 203 and the inductor unit 301 are the same as the inductor unit 100 of the first embodiment. However, any one of them may not be the inductor unit 100 of the first embodiment. Further, the number of inductors 1 included in the inductor unit 203 and the inductor unit 301 may be the same or different. It is only necessary that wireless power transmission can be performed even if only one inductor 1 of the inductor units 203 and 301 is used.

  The leakage inductance compensation capacitor may be included in one or both of the inductor unit 203 and the inductor unit 301. The compensation capacitor may be included in a circuit different from the inductor unit 203 and the inductor unit 301 such as the filters 202 and 302 and the rectifier 303.

  In addition, when the number of inductors 1 of the inductor unit 203 and the inductor unit 301 is different, the wireless power transmission device 200 is an inductor having no power transmission partner in order to reduce interference of each system when performing power transmission. A current may also flow through one winding 12.

  The high frequency power supply 201 of the wireless power transmission device 200 provided in the charging parking lot outputs a high frequency current (RF current). The structure of the high frequency power supply 201 is not particularly limited. The high frequency power supply 201 may be a single-phase power supply or a three-phase power supply. The high-frequency power source 201 includes a DC-DC converter and an inverter that outputs an RF current. Further, the high frequency power supply 201 may be provided with a regulator for adjusting the RF current, for example, a rectifier and a power factor correction circuit.

  The filter 202 suppresses harmonics generated from the high frequency power supply 201. When the harmonic component is smaller than the allowable value, the filter 202 may not be provided.

  The inductor unit 203 generates an alternating magnetic field by the input RF current. The AC magnetic field is magnetically coupled to the inductor unit 301 included in the wireless power transmission device 300 for receiving power. Thereby, electric power is transmitted.

  The inductor unit 301 of the wireless power transmission device 300 provided in the electric vehicle 400 receives the transmitted power and sends it to the rectifier 303 via the filter 302. The filter 302 prevents the harmonic component from being generated by the rectifier 303, and may not be required. The rectified power is stepped down or boosted to a desired voltage by the DC-DC converter 304. Note that the DC-DC converter 304 may not be provided. Then, the storage battery 305 is charged with the reduced or boosted power.

  As described above, the storage battery 305 included in the electric vehicle 400 is charged from the power transmission wireless power transmission device 200 included in the charging parking lot.

  Note that the four inductors 1 of the inductor unit 203 may be arranged so as to be point-symmetric. FIG. 11 is a diagram illustrating an example of a charging facility using an inductor unit 203 in which inductors are arranged point-symmetrically. Dotted lines in FIG. 11 indicate parking ranges 501 and 502 in which the electric vehicle 400 is parked. The parking range 501 indicates a parking range when parking with the longitudinal direction of the vehicle body parallel to the X-axis direction shown in FIG. A parking range 502 indicates a parking range when parking with the longitudinal direction of the vehicle body parallel to the Y-axis direction shown in FIG.

  As shown in FIG. 11, the inductors 1 of the inductor unit 203 are arranged point-symmetrically around a point equidistant from the center of each inductor 1. As shown in the example of FIG. 5, if the inductor 1 is arranged so as to be point-symmetric, the electric vehicle 400 can be charged regardless of whether it is parked in the parking range 501 or parked in the parking range 502. it can. Thereby, the parking position which can be charged can be increased.

  As described above, according to the second embodiment, the wireless power transmission device using the inductor unit 100 of the first embodiment can be used for the electric vehicle 400 and the charging facility for charging the electric vehicle 400. Moreover, when the inductor 1 of the inductor unit 100 is arranged point-symmetrically, the chargeable parking positions can be increased.

  Although one embodiment of the present invention has been described above, these embodiment are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

100 Inductor unit 1 Inductor 11 Core 12 Winding 13 Housing 14 Magnetic body 15 Bobbin 200 Wireless power transmission device (for power transmission)
201 High-frequency power source 202 Filter 203 Inductor unit (for power transmission)
300 Wireless power transmission device (for power reception)
301 Inductor unit (for power reception)
302 Filter 303 Rectifier 304 DC / DC converter 305 Storage battery 400 Electric vehicle 501, 502 Parking range A where the vehicle is parked Magnetic flux direction CL1 First center line CL2 Second center line CP Core center L11 Core length (depth)
L12 Winding length LS1, LS2 Line segment W11 Core width φ1, φ2 Angle

Claims (16)

An inductor unit including a core and a plurality of inductors each including a winding wound around the core,
First and second inductors in which the axial directions of the windings are substantially parallel;
Third and fourth inductors in which the axial direction of the windings is substantially perpendicular to the axial direction of the windings of the first and second inductors;
With
In plan view,
The first line segment connecting the center of the core of the first inductor and the center of the core of the second inductor is either parallel or perpendicular to the axial direction of the winding of the first inductor. The first and second inductors are arranged such that
The second line connecting the center of the core of the third inductor and the center of the core of the fourth inductor is either parallel or perpendicular to the axial direction of the winding of the third inductor. not do so, the third and the fourth inductor are arranged,
A first center line that passes through the center of the core of the first inductor and is parallel to the axial direction of the winding of the first inductor passes through the center of the core of the third inductor. , The second center line that is a straight line perpendicular to the axial direction of the winding of the third inductor, or the center of the core of the fourth inductor and passing through the center of the core of the fourth inductor. An inductor unit coinciding with the third center line, which is a straight line perpendicular to the axial direction . An inductor unit including a core and a plurality of inductors each including a winding wound around the core,
First and second inductors in which the axial directions of the windings are substantially parallel;
Third and fourth inductors in which the axial direction of the windings is substantially perpendicular to the axial direction of the windings of the first and second inductors;
With
In plan view,
The first line segment connecting the center of the core of the first inductor and the center of the core of the second inductor is either parallel or perpendicular to the axial direction of the winding of the first inductor. The first and second inductors are arranged such that
The second line connecting the center of the core of the third inductor and the center of the core of the fourth inductor is either parallel or perpendicular to the axial direction of the winding of the third inductor. The third and fourth inductors are arranged such that
The depth of the core included in the first inductor or the second inductor is different from the depth of the core of the third inductor or the fourth inductor.
Inductor unit. An inductor unit including a core and a plurality of inductors each including a winding wound around the core,
First and second inductors in which the axial directions of the windings are substantially parallel;
Third and fourth inductors in which the axial direction of the windings is substantially perpendicular to the axial direction of the windings of the first and second inductors;
With
In plan view,
The first line segment connecting the center of the core of the first inductor and the center of the core of the second inductor is either parallel or perpendicular to the axial direction of the winding of the first inductor. The first and second inductors are arranged such that
The second line connecting the center of the core of the third inductor and the center of the core of the fourth inductor is either parallel or perpendicular to the axial direction of the winding of the third inductor. The third and fourth inductors are arranged such that
The size of the first inductor or the second inductor is different from the size of the third inductor or the fourth inductor.
Inductor unit. at least,
An angle formed by a straight line passing through the center of the core of the first inductor and parallel to the axial direction of the winding of the first inductor and the first line segment is 50 degrees or more and 70 degrees. Or an angle formed by a straight line passing through the center of the core of the third inductor and parallel to the axial direction of the winding of the third inductor, and the second line segment is 50 The inductor unit according to any one of claims 1 to 3, wherein the inductor unit is not less than 70 degrees and not more than 70 degrees. An inductor unit including a core and a plurality of inductors each including a winding wound around the core,
First and second inductors in which the axial directions of the windings are substantially parallel;
Third and fourth inductors in which the axial direction of the windings is substantially perpendicular to the axial direction of the windings of the first and second inductors;
With
In plan view,
The first line segment connecting the center of the core of the first inductor and the center of the core of the second inductor is either parallel or perpendicular to the axial direction of the winding of the first inductor. The first and second inductors are arranged such that
The second line connecting the center of the core of the third inductor and the center of the core of the fourth inductor is either parallel or perpendicular to the axial direction of the winding of the third inductor. The third and fourth inductors are arranged such that
at least,
An angle formed by a straight line passing through the center of the core of the first inductor and parallel to the axial direction of the winding of the first inductor and the first line segment is 50 degrees or more and 70 degrees. Is
Or
An angle formed by a straight line passing through the center of the core of the third inductor and parallel to the axial direction of the winding of the third inductor and the second line segment is 50 degrees or more and 70 degrees The inductor unit, which is the following. The wireless power transmission apparatus provided with the inductor unit as described in any one of Claims 1 thru | or 5. at least,
The magnetic field generated by the winding of the first inductor and the magnetic field generated by the winding of the second inductor are in reverse phase.
Or the magnetic field generated by the winding of the third inductor and the magnetic field generated by the winding of the fourth inductor are in reverse phase,
The wireless power transmission device according to claim 6. at least,
The circuit including the first inductor and the circuit including the second inductor have the same winding direction as the winding of the first inductor and the winding of the second inductor. Connected through one inverter,
Or
A circuit including the third inductor and a circuit including the fourth inductor have the same winding direction as the winding of the third inductor and the winding of the fourth inductor. Connected through one inverter,
The wireless power transmission device according to claim 7. A first frequency that is a frequency of a fundamental wave of a current that flows in the winding of the first inductor and a frequency of a fundamental wave of a current that flows in the winding of the second inductor; and the frequency of the third inductor The wireless power transmission device according to any one of claims 6 to 8, wherein a second frequency that is a frequency of a fundamental wave of a current flowing through the winding and the winding of the fourth inductor is different. The wireless power transmission device according to claim 9, wherein the first frequency and the second frequency are separated by 200 Hz or more. The wireless power transmission device according to claim 9, wherein the first frequency and the second frequency are not separated from each other by 9 kHz. The wireless power transmission device according to any one of claims 6 to 11, wherein the transmission power of the first inductor or the second inductor is different from the transmission power of the third inductor or the fourth inductor. . The wireless power according to any one of claims 6 to 12, wherein, when performing power transmission, a current is passed through the winding of the inductor having no power transmission partner among the first to fourth inductors. Transmission equipment. An electric vehicle comprising the wireless power transmission device according to any one of claims 6 to 13. A charging facility comprising the wireless power transmission device according to any one of claims 6 to 13. The charging facility according to claim 15, wherein the first to fourth inductors are arranged point-symmetrically.