JP2015204739A - Non-contact power supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-contact power supply device that is able to restrict a decrease in transmission efficiency caused by the length of a cable.SOLUTION: A non-contact power supply device 10 comprises a cable 25 that electrically connects a power transmission antenna 21 and a power transmission synchronism matching section 23 such that they are attached to or detached from each other. Accordingly, the length of the cable 25 can be altered, and a degree of freedom in the installation of the power transmission antenna 21 and the power transmission synchronism matching section 23 is high. If the length of the cable 25 changes, input impedance caused by the cable 25 also changes. Therefore, the length of the cable 25 is estimated from a frequency characteristic when the cable 25 is oscillated from a high-frequency oscillation part 45. Then, when power from the power transmission synchronism matching section 23 is transmitted to the power transmission antenna 21, a cable matching part 41 compensates for the influence of the length of the cable on the basis of the result of the estimation of the length of the cable.

Description

  The present invention relates to a non-contact power feeding device that transmits power to a power transmission object in a non-contact manner.

  An electric vehicle such as an electric vehicle and a hybrid vehicle is equipped with a battery that can charge electric power for traveling from an external power source. Known methods for supplying power for charging include a plug-in type power supply device that connects a power supply port on the power supply side and a vehicle charging port with a cable, and a non-contact type power supply device that does not use a cable. . The non-contact power feeding apparatus is excellent in convenience because it does not require a cable, but is required to improve transmission efficiency.

  In the non-contact power transmission device described in Patent Document 1, an impedance that varies depending on a relative positional relationship between a power transmission antenna and a power reception antenna is estimated from measurement of a voltage standing wave ratio, and the estimated impedance is converted into a predetermined impedance. The optimal transmission efficiency is obtained.

JP 2012-46434 A

  Some non-contact power feeding apparatuses can attach and detach a power transmitting antenna, a power receiving antenna, and a power supply unit. For example, the power transmission antenna and the power supply unit are connected by a cable, and the length of the cable connecting the power transmission antenna and the power supply unit varies depending on the position of the power transmission antenna and the power supply unit. As the cable length changes, the cable impedance also changes. Therefore, it is preferable to transmit power from the power supply unit to the power transmission antenna in consideration of the impedance of the cable.

  However, the technique described in Patent Document 1 does not consider changes in the existing configuration such as cables, but only considers the relative positional relationship between the power transmitting antenna and the power receiving antenna. Therefore, when the cable is changed, there is a problem that the optimum transmission efficiency cannot be obtained.

  Therefore, the present invention has been made in view of the above-described problems, and an object of the present invention is to provide a non-contact power feeding device that can suppress a decrease in transmission efficiency due to the length of a cable.

  The present invention employs the following technical means in order to achieve the aforementioned object.

  The present invention relates to a cable (25) for detachably electrically connecting an antenna and a tuning matching section, a high frequency oscillation section (45) for oscillating a high frequency in the cable, and a cable length of the cable from the high frequency oscillation section to the cable. In order to compensate for the influence of the cable length based on the estimation result of the estimation unit when the power from the tuning matching unit is transmitted to the antenna, the estimation unit (43) that estimates from the frequency characteristics when the oscillation occurs A non-contact power feeding device including a cable matching unit (41).

  According to such this invention, the cable which connects an antenna and a tuning matching part electrically so that attachment or detachment is possible is provided. Therefore, the length of the cable can be changed, and the degree of freedom of installation between the antenna and the tuning matching unit is high. As the cable length changes, the input impedance variation caused by the cable occurs. Therefore, the present invention includes an estimation unit that estimates the cable length of the cable from the frequency characteristics when the cable is oscillated from the high-frequency oscillation unit. As a result, the cable length can be estimated. Further, when the power from the tuning matching unit is transmitted to the antenna, the cable matching unit compensates for the influence of the cable length based on the estimation result of the estimation unit. As a result, the influence of the cable is eliminated, so that it is possible to suppress a decrease in transmission efficiency due to the length of the cable.

  In addition, the code | symbol in the bracket | parenthesis of each above-mentioned means is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

It is the figure which shows the non-contact electric power feeder 10 simplified. 1 is a diagram illustrating a wireless sensor 11. FIG. It is a figure which shows an example of the vehicle 12 in which the wireless sensor 11 is mounted. 1 is a block diagram showing a non-contact power feeding device 10 and a wireless sensor 11. FIG. It is a figure for demonstrating the electrical characteristic seen from the tuning matching part 23 for power transmission. It is a graph which shows the relationship between cable length and input capacity. 2 is a block diagram showing an electrical configuration of the non-contact power feeding apparatus 10. FIG. 2 is a block diagram showing a part of the configuration of the non-contact power feeding device 10 in detail. FIG. It is a flowchart which shows the setting process of a phase shift amount. 3 is a graph showing frequency characteristics of a cable 25. It is a flowchart which shows the setting process of the phase shift amount of 2nd Embodiment. It is a graph for demonstrating an example of a measurement example. It is a graph for demonstrating the other example of a measurement example. It is a block diagram which shows the electric constitution of 10 A of non-contact electric power supply of 3rd Embodiment. It is a front view which shows the switch part 42B of 4th Embodiment. FIG. 16 is a cross-sectional view seen from the section line II in FIG. 15. 3 is a front view showing an end portion 25a of a cable 25. FIG. FIG. 18 is a cross-sectional view seen from a cutting plane line II-II in FIG. 17. It is a figure which shows the state which has the edge part 25a of the cable 25 in an estimated state. It is a figure which shows the state which has the edge part 25a of the cable 25 in an intermediate state. It is a figure which shows the state which has the edge part 25a of the cable 25 in the electric power feeding state.

  Hereinafter, a plurality of embodiments for carrying out the present invention will be described with reference to the drawings. In some embodiments, portions corresponding to the matters described in the preceding embodiments may be given the same reference numerals, or one letter may be added to the preceding reference numerals, and overlapping descriptions may be omitted. In addition, when a part of the configuration is described in each embodiment, the other parts of the configuration are the same as those of the embodiment described in advance. In addition to the combination of parts specifically described in each embodiment, the embodiments may be partially combined as long as the combination does not hinder the combination.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS. The non-contact power supply device 10 supplies power to the non-contact power receiving device in a non-contact manner. The non-contact power feeding device 10 is used for supplying wireless power to a wireless sensor 11 to be attached to a vehicle body such as a bumper as shown in FIGS. Therefore, the wireless sensor 11 also has a function as a non-contact power receiving device. As shown in FIG. 4, the non-contact power feeding apparatus 10 includes a power transmission antenna 21, an adjustment unit 22, a power transmission tuning and matching unit 23, a cable 25, and a power supply unit 26. As shown in FIG. 4, the wireless sensor 11 includes a power receiving antenna 31, a power receiving tuning and matching unit 32, and a sensor unit 33.

  The power supply unit 26 is a power source having power to be transmitted to the sensor unit 33. The power supply unit 26 is connected to a main battery mounted on the vehicle 12, converts DC power of the main battery into AC power (DC / AC conversion), and supplies the AC power to the tuning matching unit 23 for power transmission.

  The tuning matching unit for power transmission 23 is tuned with the power from the power supply unit 26, is matched to improve the gain, and is supplied to the adjustment unit 22. The adjustment unit 22 performs power adjustment described later, and supplies the adjusted power to the power transmission antenna 21 via the cable 25. The power transmission antenna 21 supplies the power supplied from the adjustment unit 22 to the power receiving antenna 31 outside without contact.

  The power receiving antenna 31 receives power supplied from the power transmitting antenna 21 in a contactless manner and supplies the power to the power receiving tuning matching unit 32. The power receiving tuning matching unit 32 is tuned with the power from the power transmitting antenna 21, is matched to improve the gain, and is supplied to the sensor unit 33. The sensor unit 33 is driven by supplied electric power and functions as an optical sensor and an infrared sensor, for example.

  Thus, the power transmission antenna 21 functions as a power supply surface and is mounted on the surface of the vehicle body as shown in FIG. The power transmission antenna 21 is designed to be as thin and flexible as possible in order to maintain a design suitable for the vehicle 12 and aerodynamic characteristics. The power transmission antenna 21 is selected to have an arbitrary size so as to correspond to various mounting locations.

  On the other hand, the power transmission tuning and matching unit 23 is a portion having thickness and rigidity, and in order to secure the degree of freedom of installation of the power transmission antenna 21, the power transmission antenna 21 and the power transmission tuning and matching unit 23 are separated. There is a need to. Then, when the power transmission tuning and matching unit 23 and the power transmission antenna 21 are separated, it is necessary to connect them with a cable 25. Furthermore, it is necessary to assume that the cable length to the power transmission tuning matching unit 23 can also be an arbitrary length.

Next, the electrical characteristics of the power transmission antenna 21 viewed from the power supply unit 26 side will be described. As shown in FIG. 5, when the impedance viewed from the transmission tuning matching unit 23 is Cin, Cin can be expressed by Expression (3) based on Expression (1) and Expression (2).

  Therefore, the relationship between the input capacitance Cin and the cable length l is as shown in the graph in FIG. As shown in FIG. 6, the electrical characteristics of the power transmission antenna 21 as viewed from the power supply unit 26 side greatly change depending on the cable length, so that the power transmission efficiency is greatly reduced as it is. Therefore, it is necessary for the adjusting unit 22 to cancel the electrical characteristics that change depending on the cable length and maintain the tuning. A common method for tuning is to connect a variable capacitor in series and directly cancel out the increment of the input capacitance. As shown in FIG. 6, depending on the cable length, the input capacitance is infinite, 0 and negative. There are cases where tuning cannot be performed simply with an additional capacitor. For this reason, the adjustment unit 22 performs matching control specialized for the cable 25.

  Next, the configuration of the non-contact power feeding device 10 will be described in more detail with reference to FIGS. 7 and 8. As shown in FIG. 7, the adjustment unit 22 includes a cable matching unit 41, a switching unit 42, a control unit 43, a measurement unit 44, and a high-frequency oscillation unit 45. The frequency characteristic of the cable 25 shows a periodic characteristic depending on the cable length. The control unit 43 detects this cycle and estimates the cable length. The adjustment unit 22 estimates the cable length using the high frequency by the control unit 43, and tunes based on the estimation result by the cable matching unit 41.

  The switching unit 42 switches between the estimation state estimated by the control unit 43 and the power supply state in which the electric power from the power supply unit 26 is contactlessly fed from the power transmission antenna 21. The switching unit 42 is electrically connected between the cable matching unit 41 and the cable 25. Specifically, the switching unit 42 includes an estimated state in which the high-frequency oscillation unit 45 and the cable 25 are electrically connected, and a power supply state in which the cable matching unit 41 and the power transmission antenna 21 are electrically connected. Change over. The switching is realized by a mechanical switch such as a push switch or an electrical switch such as a switching element.

  The high frequency oscillator 45 oscillates the cable 25 at a high frequency. At this time, a frequency sufficiently higher than the power transmission frequency is used so that the cable length can be estimated even if an arbitrary power transmission antenna 21 (electrode) is connected. Therefore, the high frequency oscillating unit 45 oscillates a high frequency in a frequency band equal to or more than a certain multiple of the power transmission frequency. As a result, the impedance of the power transmission antenna 21 can be approximated to 0 regardless of its type. The measurement unit 44 measures the frequency characteristics of the cable 25 when oscillated from the high-frequency oscillation unit 45 to the cable 25, and gives the measurement result to the control unit 43.

  The control unit 43 estimates the cable length from the terminal in the opposite direction from the power transmission antenna 21, that is, the frequency characteristic of the input impedance viewed from the power supply unit 26 side. Therefore, the control unit 43 functions as an estimation unit that estimates the cable length from the frequency characteristics when the cable length is oscillated from the high frequency oscillation unit 45 to the cable 25.

  As shown in FIG. 7, the cable matching unit 41 is electrically connected between the power transmission tuning matching unit 23 and the cable 25. The cable matching unit 41 implements a tuning method that compensates for the estimated cable length. Although there are various tuning methods, there is a method using a phase shifter 46 as shown in FIG. The cable matching unit 41 calculates a phase shift amount for tuning and performs phase shift of the calculated phase shift amount. Specifically, the cable matching unit 41 sets the phase shift amount so that the sum of the phase delay of the cable 25 at the power transmission frequency transmitted from the power supply unit 26 is a multiple of 180 degrees. Therefore, the virtual cable length when the phase shifter 46 and the cable 25 are included is set to be a multiple of a half wavelength.

  Next, control for setting the phase shift amount by the control unit 43 will be described with reference to FIGS. 9 and 10. The process shown in FIG. 9 is started in a state where the switching unit 42 is switched to the estimated state and the control unit 43 is set in a setting mode for setting the cable length in advance.

  In step S1, the frequency of the high-frequency oscillator 45 is set to the minimum frequency, the reactance is measured, and the process proceeds to step S2. In step S2, a certain value is added to the frequency of the high-frequency oscillator 45, the reactance is measured, and the process proceeds to step S3. In step S3, it is determined whether or not the reactance is the same as in the previous measurement. If the reactance is the same, the process proceeds to step S4. If the reactance is different, the process proceeds to step S5.

  In step S4, since the sign is the same, it is determined whether or not the frequency of the high-frequency oscillation unit 45 is equal to or higher than the maximum frequency. If the frequency is equal to or higher than the maximum frequency, the process proceeds to step S9. Thus, in steps S1 to S4, the reactance is measured by increasing the oscillation frequency of the high-frequency oscillator 45 stepwise until the maximum frequency is exceeded or the sign of the reactance changes.

  In step S5, since the sign of the reactance has changed, the oscillation frequency in which the sign has changed is substituted for the first frequency f1, and the process proceeds to step S6. In step S6, a certain value is added to the frequency of the high-frequency oscillator 45, the reactance is measured, and the process proceeds to step S7. In step S7, it is determined whether or not the sign of reactance is the same as that in the previous measurement. If the reactance is the same, the process proceeds to step S8, and if not, the process proceeds to step S10.

  In step S8, since the sign is the same, it is determined whether or not the frequency of the high-frequency oscillating unit 45 is equal to or higher than the maximum frequency. If the frequency is equal to or higher than the maximum frequency, the process proceeds to step S9. In step S9, since the frequency is equal to or higher than the maximum frequency, the minimum frequency is substituted for the first frequency f1, the maximum frequency is substituted for the second frequency f2, and the process proceeds to step S11.

  In step S10, since the sign of the reactance has changed, the oscillation frequency in which the sign has changed is substituted for the second frequency f2, and the process proceeds to step S11. In step S11, the phase shift amount for tuning is calculated by the equation shown in step S11, and this flow ends. As described above, the phase shift amount is set so that the sum of the phase delay of the cable 25 at the power transmission frequency is a multiple of 180 degrees.

  Thus, in this flow, the reactance of the cable 25 is measured in a frequency range having a sufficient width from the minimum frequency to the maximum frequency, and two frequencies at which the value becomes 0 are measured. The frequency that becomes 0 can be obtained by measurement by reversing the positive and negative. Then, the phase shift amount is calculated from the first frequency f1 and the second frequency f2 at which the reactance becomes zero.

  Accordingly, the cable matching unit 41 sets the phase shifter 46 so as to shift the calculated phase shift amount. As a result, at the time of non-contact power feeding, the power phase-shifted by the cable matching unit 41 is supplied to the power transmission antenna 21.

Next, calculation of the phase shift amount will be described with reference to FIG. Θ on the vertical axis gradually approaches 0 as the frequency f increases. Therefore, when f is sufficiently large, for example, about 100 times the power transmission frequency, the reactance frequency characteristic Xin (f) of the cable 25 with the power transmission antenna 21 is as shown in FIG. 10, Equation (4), and Equation (5). It becomes a tangent line and shows periodicity.

The period F at this time can be calculated by the following equation (6).

The cable length l can be estimated by the following equation (7) using the period F of the equation (6).

When calculating the period F by measurement, it is sufficient to find two consecutive points where the reactance appearing in 1/2 period becomes zero. When the two points obtained by the process shown in FIG. 9 are the first frequency f1 and the second frequency f2, the cable length l is expressed by the following equation (8).

  As described above, the non-contact power feeding device 10 of the present embodiment includes the cable 25 that detachably electrically connects the power transmission antenna 21 and the power transmission tuning matching unit 23. Therefore, the length of the cable 25 can be changed, and the degree of freedom of installation of the power transmission antenna 21 and the power transmission tuning matching unit 23 is high. As the length of the cable 25 changes, the input impedance variation caused by the cable 25 occurs. Therefore, in the present embodiment, the cable length of the cable 25 is estimated from the frequency characteristics when the cable 25 is oscillated from the high frequency oscillator 45 to the cable 25. The cable matching unit 41 compensates for the influence of the cable length based on the estimation result of the cable length when the power from the power transmission tuning matching unit 23 is transmitted to the power transmission antenna 21. As a result, the influence of the cable 25 is removed, so that a reduction in transmission efficiency due to the length of the cable 25 can be suppressed.

  In the present embodiment, the high frequency oscillating unit 45 oscillates the frequency in the cable 25 by changing the frequency stepwise. And the control part 43 estimates cable length based on the periodicity of the frequency characteristic of the cable 25 obtained by oscillating to the cable 25 from the high frequency oscillation part 45 in steps. Thus, the cable length can be estimated and the phase shift amount can be calculated.

  Furthermore, in this embodiment, the control unit 43 estimates the cable length from the zero-point frequency of reactance obtained by oscillating the cable 25 from the high-frequency oscillating unit 45 in stages. The zero point of the reactance is a frequency at which the sign of the reactance obtained by measurement is reversed. By knowing the frequency at which the reactance is zero, the amount of phase shift that can ignore the cable length can be calculated.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. The present embodiment is characterized in that not the continuous frequency characteristics of the cable 25 but the characteristics of only two frequencies (two frequencies) of the cable 25 are measured and the phase shift amount is calculated.

  The control for setting the phase shift amount by the control unit 43 of this embodiment will be described with reference to FIG. The process shown in FIG. 11 is started in a state where the switching unit 42 is switched to the estimated state and the control unit 43 is set in a setting mode for setting the cable length in advance.

  In step S11, the frequency of the high-frequency oscillator 45 is set to the first frequency f1, the reactance Xin1 is measured, and the process proceeds to step S12. In step S12, the frequency of the high-frequency oscillator 45 is set to the second frequency f2, the reactance Xin2 is measured, and the process proceeds to step S13.

  In step S13, Xin1 of f1 and Xin2 of f2 are compared. If Xin2 is large, the process proceeds to step S14, and if not, the process proceeds to step S15. In step S14, the phase shift amount for tuning is calculated by the equation shown in step S14, and this flow is finished. In step S15, the phase shift amount for tuning is calculated by the equation shown in step S15, and this flow ends.

Next, calculation of the phase shift amount will be described with reference to FIGS. Θ included in the vertical axis Xin gradually approaches 0 as the frequency f increases. Therefore, when f is sufficiently large, for example, about 100 times the power transmission frequency, the reactance frequency characteristic Xin (f) of the cable 25 with the power transmitting antenna 21 is shown in FIGS. As shown in (), it becomes a tangent line and shows periodicity. As shown in FIGS. 12 and 13, when the frequency is sufficiently high, the cable length is expressed in a form including an inconstant n as shown in the following equation (9).

Although it is impossible to identify the indefinite number n shown in Equation (9), the indefinite number n can be canceled by calculation between two measurement points within the same or adjacent period, and the correct cable length can be obtained. Here, the measurement points f1 and f2 are always located within the same period (refer to FIG. 12) or adjacent periods (refer to FIG. 13). ).

  As described above, the difference between the two frequencies f2-f1 must be sufficiently small. Further, as the characteristic values of the cable 25, the characteristic impedance Z0 and the shortening rate εr need to be known.

  As described above, in the present embodiment, the high-frequency oscillator 45 oscillates two frequencies in the cable 25. Then, the control unit 43 estimates the cable length based on the two frequency characteristics obtained from the two frequencies oscillated from the high frequency oscillation unit 45. The phase shift amount can be calculated from these two frequencies. As a result, the phase shift amount can be calculated in a shorter time. Therefore, similar to the first embodiment described above, it is possible to achieve the operation and effect obtained by setting the phase shift amount.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIG. The present embodiment is characterized in that the switching unit 42 </ b> A is electrically connected between the power transmission tuning and matching unit 23 and the power supply unit 26.

  When the switching unit 42 </ b> A is disposed between the power transmission tuning and matching unit 23 and the power supply unit 26, the control system can be mounted on the same substrate as the power supply unit 26. However, the frequency oscillated from the high-frequency oscillation unit 45 at this time becomes the frequency characteristic of the input impedance including the power transmission tuning matching unit 23. Therefore, the correction unit 50 that acquires the characteristics of the tuning matching unit for power transmission 23 and cancels it is disposed in front of the measurement unit 44 and the high-frequency oscillation unit 45. As a result, the measurement value acquired by the measurement unit 44 has the same frequency characteristics as in the first embodiment. Therefore, even when the switching unit 42A is in the position of the present embodiment, the phase shift amount calculation method in the first embodiment and the second embodiment described above can be applied.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described with reference to FIGS. The present embodiment is characterized by the configuration of the switching unit 42B. The switching unit 42B has a mechanism for selecting the connection destination of the cable 25 as either the high-frequency oscillation unit 45 or the power supply unit 26. The switching part 42B has an insertion part 60 into which the end part 25a of the cable 25 is inserted.

  The end portion 25a of the cable 25 is provided with a power supply terminal 71 for setting the power supply state and an estimation terminal 72 for setting the estimation state. The power supply terminal 71 is electrically connected to the power transmission conductor 73 inside the cable 25 and provided at the tip. The estimation terminal 72 is electrically connected to the power transmission conductor 73 inside the cable 25 and provided on the side surface. Therefore, the power transmission wire 73 is divided into two forks at the tip. The power supply terminal 71 protrudes from a covering material 74 that covers the power transmission conductor 73. As shown in FIGS. 17 and 18, the estimated terminal 72 is provided in the covering material 74 and is exposed in a recess 75 that is recessed inward in the radial direction.

  A feeding terminal receiving portion 61 to which a feeding terminal 71 is electrically connected at an insertion completion position, and an estimation terminal 72 to which an estimation terminal 72 is electrically connected between the insertion start position and the insertion completion position are inserted into the insertion portion 60. A receiving part 62 is provided. The feeding terminal receiving portion 61 is electrically connected to the cable matching portion 41 and is provided on the bottom 63 of the insertion portion 60 as shown in FIG. The estimated terminal receiving portion 62 is electrically connected to the high frequency oscillating portion 45 and provided on the inner peripheral surface 64 of the insertion portion 60. As shown in FIG. 16, the estimated terminal receiving portion 62 is made of a spring having elasticity, and the open side of the insertion portion 60 has conductivity, and the bottom 63 side has insulation.

  Next, the operation of the switching unit 42B will be described. In the estimated state shown in FIG. 19, the estimated terminal receiving part 62 and the estimated terminal 72 are in contact. In the position shown in FIG. 20, the estimated terminal 72 is in contact with the insulating portion 62 a of the estimated terminal receiving portion 62, and the power supply terminal 71 is not yet in contact with the power supply terminal receiving portion 61. Therefore, in the intermediate state shown in FIG. 20, the power transmission conductor 73 of the cable 25 is not electrically connected to any terminal. In the power supply state shown in FIG. 21, the power supply terminal 71 is in contact with the power supply terminal receiving portion 61, and the estimated terminal 72 is in contact with the insulating portion 62 a of the estimated terminal receiving portion 62.

  As shown in FIG. 19, when the end portion 25 a of the cable 25 is gradually inserted into the insertion portion 60, first, the estimated terminal 72 comes into contact with the conductive portion 62 b of the estimated terminal receiving portion 62. When the terminal is further inserted as it is, the estimated terminal 72 compresses the estimated terminal receiving part 62, and the estimated terminal 72 and the estimated terminal receiving part 62 are in contact with each other until the intermediate state shown in FIG.

  And if it inserts further as it is, the electric power feeding terminal 71 will compress the electric power feeding terminal receiving part 61, and will be in the electric power feeding state shown in FIG. In this case, the estimated terminal 72 is in contact with the insulating portion 62 a of the estimated terminal receiving portion 62. Therefore, the power transmission lead 73 of the cable 25 is electrically connected only to the power supply terminal 71.

  As shown in FIG. 19, the minimum contact distance> the maximum contact distance, and the remaining contact length + contact contact length is designed to be sufficiently large. The distance and length here mean the distance and length along the flow line when the terminal is inserted. When the user inserts the cable 25, the cable 25 and the high-frequency oscillating unit 45 are electrically connected only during the time from the start of insertion to the intermediate state, and at this time, the cable length is estimated. Accordingly, the end 25a of the cable 25 is inserted into the insertion portion 60, and at least a part of the insertion position from the insertion start position to the insertion completion position is in an estimated state. In a state where the end portion 25a of the cable 25 is disposed at the insertion completion position, the power supply state is established.

  As described above, the switching unit 42B switches between the estimation state and the power supply state according to the position where the end 25a of the cable 25 is inserted into the insertion unit 60. As a result, the connection between the power supply unit 26 and the high-frequency oscillation unit 45 can be switched mechanically without using a switching element. Further, the cable length is measured by a series of operations for connecting the cable 25 and the switching unit 42B. Therefore, connection work can be performed efficiently.

(Other embodiments)
The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  The structure of the said embodiment is an illustration to the last, Comprising: The scope of the present invention is not limited to the range of these description. The scope of the present invention is indicated by the description of the scope of claims, and further includes meanings equivalent to the description of the scope of claims and all modifications within the scope.

  In the first embodiment described above, the non-contact power feeding device 10 is mounted on the vehicle 12, but is not limited to the vehicle 12 and may be mounted on another device.

  In the first embodiment described above, the contactless power supply device 10 and the wireless sensor 11 are mounted on the same device, but may be mounted on different devices. For example, when the wireless sensor 11 is a charging method, the non-contact power feeding device 10 may be arranged at a predetermined position when charging.

  In the first embodiment described above, the electric field coupling method is used as the non-contact power supply method, but is not limited to the electric field coupling method. For example, an electromagnetic coupling method may be used.

10 ... Non-contact power feeding device 21 ... Power transmission antenna (antenna)
DESCRIPTION OF SYMBOLS 23 ... Power transmission tuning matching part (tuning matching part) 25 ... Cable 25a ... Cable end part 26 ... Power supply part 41 ... Cable matching part 42 ... Switching part 43 ... Control part (estimation part) 44 ... Measurement part 45 ... High frequency oscillation Portion 46 ... Phase shifter 60 ... Insertion portion 61 ... Feeding terminal receiving portion 62 ... Estimated terminal receiving portion 71 ... Feeding terminal 72 ... Estimating terminal

Claims (12)

A tuning matching unit (23) connected to the power supply unit (26) and tuned and matched to supply power from the power supply unit in a non-contact manner;
An antenna (21) for supplying power from the tuning matching unit to the outside in a non-contact manner;
A cable (25) for detachably electrically connecting the antenna and the tuning matching section;
A high-frequency oscillation section (45) for oscillating a high frequency in the cable;
An estimation unit (43) for estimating a cable length of the cable from a frequency characteristic when the cable is oscillated from the high-frequency oscillation unit to the cable;
A cable matching unit (41) that tunes to compensate for the influence of the cable length based on the estimation result of the estimation unit when transmitting power from the tuning matching unit to the antenna;
A non-contact power feeding apparatus comprising: a switching unit (42) that switches between an estimation state estimated by the estimation unit and a power feeding state in which power from the power source unit is contactlessly fed from the antenna.   The non-contact power feeding apparatus according to claim 1, wherein the high-frequency oscillation unit oscillates a high frequency in a frequency band that is equal to or higher than a certain multiple of a power transmission frequency.   The non-contact power feeding apparatus according to claim 1, wherein the cable matching unit is electrically connected between the tuning matching unit and the cable.   The non-contact power feeding apparatus according to claim 1, wherein the cable matching unit calculates a phase shift amount for tuning and shifts the phase by the calculated phase shift amount. The high-frequency oscillation unit oscillates the frequency in the cable by changing the frequency step by step,
The said estimation part estimates the said cable length based on the periodicity of the frequency characteristic of the said cable obtained by oscillating to the said cable in steps from the said high frequency oscillation part. The non-contact electric power feeder as described in any one of these.   6. The non-contact power feeding according to claim 5, wherein the estimation unit estimates the cable length from a zero-point frequency of reactance obtained by oscillating the cable in stages from the high-frequency oscillation unit. apparatus. The high-frequency oscillator oscillates two frequencies in the cable,
The said estimation part estimates the said cable length based on the two frequency characteristics obtained from the two frequencies oscillated from the said high frequency oscillation part, The Claim 1 characterized by the above-mentioned. Non-contact power supply device.   The said cable matching part sets the said phase shift amount so that the sum with the phase delay of the said cable in the electric power transmission frequency transmitted from the said power supply part may be a multiple of 180 degree | times. The non-contact electric power feeder as described in.   The non-contact power feeding device according to claim 1, wherein the switching unit is electrically connected between the cable matching unit and the cable.   The contactless power feeding device according to claim 1, wherein the switching unit is electrically connected between the tuning matching unit and the power supply unit. The switching part has an insertion part (60) into which an end of the cable is inserted,
According to the position where the end (25a) of the cable is inserted into the insertion portion, the estimated state and the power supply state are switched,
At least a part of the insertion position between the end of the cable inserted into the insertion part and inserted into the insertion completion position from the insertion start position becomes the estimated state,
The contactless power feeding device according to any one of claims 1 to 10, wherein the power feeding state is established when the end portion of the cable is disposed at the insertion completion position. At the end of the cable, a power supply terminal (71) for setting the power supply state and an estimation terminal (72) for setting the estimated state are provided,
The insertion portion is electrically connected to the feeding terminal receiving portion (61) to which the feeding terminal is electrically connected at the insertion completion position and between the insertion start position to the insertion completion position. The non-contact electric power feeder according to claim 11 provided with an estimated terminal receiving part (62) connected.

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