JP2011125184A - Noncontact power supply facility, noncontact power receiving apparatus, and noncontact power supply system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To measure a temperature of a capacitor without installing a temperature detection element such as a thermocouple in noncontact power supply by a resonance system where a coil and the capacitor are connected. <P>SOLUTION: Noncontact power supply is performed from a primary side to a secondary side by resonance of a primary self-resonance coil 30 of the primary-side (power supply facility) and a secondary self-resonance coil 70 of the secondary side (power reception device) through an electromagnetic field. Power transmission efficiency (P2/P1) in each frequency is obtained when a frequency setting part 42 changes stepwisely a power transmission frequency of a high frequency power supply 10. Thus, a resonance frequency estimating part 45 estimates a power transmission frequency having the maximum power transmission efficiency value as a present resonance frequency. A temperature estimating part 46 calculates back a capacity change of the capacitors 35 and 75 by a change of the capacitor temperature from the estimated resonance frequency, and applies the capacity change calculated back to a temperature characteristic of the capacitor capacity which is previously stored in a temperature characteristic storage part 47. Thus, the capacitor temperature Tc is estimated. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a non-contact power supply facility, a non-contact power receiving apparatus, and a non-contact power supply system, and more specifically, a non-contact power supply that performs non-contact power supply by resonance via an electromagnetic field between a power transmission side and a power reception side. The present invention relates to a facility, a contactless power receiving device, and a contactless power feeding system.

  Electric vehicles such as electric vehicles and hybrid vehicles are attracting attention as environmentally friendly vehicles. These vehicles are equipped with an electric motor that generates a driving force and a rechargeable power storage device that applies electric power supplied to the electric motor. The hybrid vehicle is a vehicle that further includes an internal combustion engine as a power source together with an electric motor, or a vehicle that further includes a fuel cell as well as a power storage device as a DC power source for driving the vehicle.

  In a hybrid vehicle as well as an electric vehicle, a configuration capable of charging an in-vehicle power storage device from a power source outside the vehicle is known. For example, a so-called “plug-in hybrid vehicle” is known in which a power storage device can be charged from a generally assumed power source by connecting a power outlet provided in a house and a charging port provided in a vehicle with a charging cable. Yes.

  On the other hand, as a power transmission method, wireless power transmission that does not use a power cord or a power transmission cable has recently attracted attention. As this wireless power transmission technology, three technologies known as power transmission using electromagnetic induction, power transmission using microwaves, and power transmission using a resonance method are known.

  Among these, the resonance method is a non-contact power transmission technique in which a pair of resonators (for example, a pair of self-resonant coils) are resonated in an electromagnetic field (near field) and transmitted through the electromagnetic field, and has a high power of several kW. Can be transmitted over a relatively long distance (for example, several meters) (see, for example, Patent Document 1).

  Japanese Unexamined Patent Application Publication No. 2009-106136 (Patent Document 2) describes a configuration of an electric vehicle that can charge an in-vehicle power storage device with electric power wirelessly received from a power source outside the vehicle by a resonance method.

  In addition, regarding non-contact power feeding of a semiconductor device (IC card), Japanese Patent Laying-Open No. 2008-35405 (Patent Document 3) describes a relatively small capacitive element with respect to a resonance circuit including a power receiving antenna element and a capacitive element. A configuration is described in which it is arranged near a constant voltage circuit that generates a large amount of heat. With this configuration, when the electric power supplied by electromagnetic coupling becomes excessive at the time of non-contact power feeding, the resonance frequency of the resonance circuit changes due to the capacitance of the capacitive element changing due to the heat generated by this. As a result, the temperature rise inside the apparatus due to the supply of excess power can be suppressed.

  JP 2007-315854 (Patent Document 4) discloses that a high temperature is applied based on a change in capacitance of a capacitor configured to move an electrode in accordance with strain on the surface of an object to be measured. It describes that a strain measuring device is configured. Furthermore, even if the positional relationship between the electrodes is fixed, the output of the strain measuring device, that is, the capacitance of the capacitor changes according to the temperature change, and the output can be compensated by reflecting this temperature characteristic. Are listed.

International Publication No. 2007/008646 Pamphlet JP 2009-106136 A JP 2008-35405 A JP 2007-315854 A

  In the contactless power supply configurations described in Patent Documents 1 to 4, since power is transmitted by resonance between the resonators or the resonance coils, a resonance capacitor is connected to the coil in order to adjust the resonance frequency in the resonance system. A configuration is used. In such a configuration, if a thermocouple or the like is connected to the capacitor in order to measure the temperature of the resonance capacitor, the following problems may occur.

  First, in the power transmission by the resonance method, high frequency power is transmitted, so that noise generated from the coil also has a very high frequency. For this reason, high-frequency noise affects the output of the thermocouple, which may make accurate temperature measurement difficult. In addition, adding a filter for noise suppression is disadvantageous in terms of cost.

  Secondly, in a resonance system in which a relatively high voltage is transmitted, such as power feeding to an electric vehicle such as Patent Document 2, by bringing a metal object such as a thermocouple close to the capacitor, the withstand voltage of the capacitor is reduced. There is a risk of causing dielectric breakdown between the electrode plates.

  The present invention has been made to solve such problems, and an object of the present invention is to provide a temperature detection element such as a thermocouple in non-contact power feeding by a resonance system to which a coil and a capacitor are connected. Without measuring the temperature of the capacitor.

  A non-contact power supply facility according to the present invention includes a power supply device, a power transmission resonator, and a control device. The power supply device is configured to generate high-frequency power at a controllable frequency. The power transmitting resonator is configured to transmit power from the power supply device to the power receiving device in a contactless manner by resonating with the power receiving resonator of the power receiving device via an electromagnetic field. The control device is configured to control the power supply device and the power transmission resonator. The power transmission resonator includes a primary self-resonant coil and a primary capacitor connected to the primary self-resonant coil. The primary self-resonant coil is configured to generate an electromagnetic field when fed with high-frequency power. The control device includes a temperature measurement requesting unit for generating a temperature measurement request for the primary capacitor when a predetermined condition is satisfied, an efficiency acquisition unit for obtaining power transmission efficiency from the power transmission resonator to the power reception resonator, and a temperature measurement Acquired by the frequency setting unit for changing the frequency of the power supply device in multiple stages at the time of request, an information storage unit for storing information on the temperature characteristics of the capacity of the primary capacitor, and the efficiency acquisition unit at the time of temperature measurement request A frequency estimation unit for estimating the resonance frequency of the power transmission resonator based on the transmission efficiency in each of the plurality of stages, and the capacitance of the primary capacitor estimated from the estimated resonance frequency and the inductance of the primary self-resonant coil And a temperature estimation unit for calculating an estimated temperature value of the primary capacitor based on the information stored in the information storage unit.

A non-contact power receiving device according to the present invention includes a power receiving resonator and a control device. The power receiving resonator is configured to resonate with a power transmitting resonator that receives high frequency power from a power supply device configured to generate high frequency power at a controllable frequency via an electromagnetic field, thereby transmitting power from the power transmitting resonator. Is provided so as to receive power without contact. The control device is configured to control the power supply device and the power receiving resonator. The power receiving resonator includes a secondary self-resonant coil and a secondary capacitor connected to the secondary self-resonant coil. The secondary self-resonant coil is configured to receive power from the primary self-resonant coil in a non-contact manner by resonating with the primary self-resonant coil of the power transmission resonator via the electromagnetic field. The control device includes a temperature measurement requesting unit for generating a temperature measurement request for the secondary capacitor when a predetermined condition is satisfied, an efficiency acquisition unit for obtaining power transmission efficiency from the power transmission resonator to the power receiving resonator, A frequency setting unit that changes the frequency of the power supply device in multiple stages from a predetermined power transmission frequency when a temperature is requested, an information storage unit that stores information about the temperature characteristics of the secondary capacitor capacity, and an efficiency acquisition when a temperature measurement is requested The frequency estimation unit for estimating the resonance frequency of the power receiving resonator, and the estimated resonance frequency and the inductance of the secondary self-resonance coil are estimated based on the transmission efficiency in each of the plurality of stages acquired by the unit. A temperature estimation unit for calculating a temperature estimation value of the secondary capacitor based on the capacity of the secondary capacitor and the information stored in the information storage unit is included.

  A non-contact power feeding system according to the present invention includes a power feeding facility for transmitting high-frequency power, a power receiving device for receiving power transmitted from the power feeding facility in a contactless manner, and a control for controlling the power feeding facility and the power receiving device. Device. The power supply facility includes a power supply device and a power transmission resonator. The power supply device is configured to generate high-frequency power at a controllable frequency. The power transmitting resonator is configured to transmit high-frequency power from the power supply device to the power receiving device in a non-contact manner by resonating via an electromagnetic field. The power transmission resonator includes a primary self-resonant coil and a primary capacitor connected to the primary self-resonant coil. The primary self-resonant coil is configured to generate an electromagnetic field when fed with high-frequency power. The power receiving device includes a power receiving resonator that receives power transmitted from the power transmitting resonator in a contactless manner. The power receiving resonator includes a secondary self-resonant coil and a secondary capacitor connected to the secondary self-resonant coil. The secondary self-resonant coil is configured to receive power from the primary self-resonant coil in a non-contact manner by resonating with the primary self-resonant coil of the power transmission resonator via the electromagnetic field. The control device includes a temperature measurement requesting unit for generating a temperature measurement request for the primary and secondary capacitors when a predetermined condition is satisfied, and an efficiency acquisition unit for obtaining power transmission efficiency from the power transmission resonator to the power reception resonator. A frequency setting unit that changes the frequency of the power supply device in a plurality of stages from a predetermined power transmission frequency at the time of temperature measurement request, an information storage unit that stores information on the temperature characteristics of the capacities of the primary and secondary capacitors, and a temperature measurement request Sometimes, a frequency estimator that estimates the resonance frequency of the power transmitting resonator and the power receiving resonator based on the transmission efficiency in each of the plurality of stages acquired by the efficiency acquisition unit, the estimated resonance frequency, and the primary and secondary Based on the capacity of the primary and secondary capacitors estimated from the inductance of the self-resonant coil and the information stored in the information storage unit, the primary and secondary capacitors Of and a temperature estimation unit for calculating a temperature estimated value.

  Preferably, in the non-contact power supply facility, the non-contact power reception device, or the non-contact power supply system, the temperature measurement request includes the first request generated at the start of the power transmission process from the power supply facility to the power reception device, and the power transmission And a second request generated in the middle of processing. The frequency setting unit is configured to change the frequency of the power supply device from a predetermined power transmission frequency to a plurality of stages in response to the first and second requests. The frequency estimation unit estimates an initial value of the resonance frequency based on the power transmission efficiency in each of the plurality of stages at the time of the first request, and resonates based on the power transmission efficiency in each of the plurality of stages at the time of the second request. Estimate the current frequency value. The temperature estimation unit obtains the initial temperature of the primary and / or secondary capacitor based on the ambient temperature at the time of the first request, and is estimated from the relationship between the initial value and the current value of the resonance frequency at the time of the second request. An estimated temperature value is calculated based on the change in the capacitance of the primary and / or secondary capacitor, the initial temperature, and the information stored in the information storage unit.

  Preferably, in the non-contact power supply facility, the non-contact power receiving device, or the non-contact power supply system, the control device calculates the temperature estimated until the temperature estimation value is calculated by the temperature estimation unit in response to the temperature measurement request. A temperature measurement interval setting unit for variably setting the temperature measurement interval according to the temporal transition of the estimated value is further included. The temperature measurement request unit generates the next temperature measurement request when the temperature measurement interval elapses from the generation of the current temperature measurement request.

Alternatively, preferably, in the non-contact power supply facility, the non-contact power receiving apparatus, or the non-contact power supply system, a cooling mechanism for the primary capacitor and / or the secondary capacitor is further provided. The control device further includes a cooling control unit configured to control the operation of the cooling mechanism based on the temperature estimation value calculated by the temperature estimation unit.

  Preferably, in the non-contact power supply facility, the non-contact power reception device, or the non-contact power supply system, the efficiency acquisition unit is configured to sequentially obtain the power transmission efficiency during the power transmission process from the non-contact power supply facility to the power reception device. . And the temperature measurement request | requirement part is comprised so that a temperature measurement request | requirement may be generate | occur | produced when power transmission efficiency falls from a predetermined value during power transmission processing.

  Alternatively, preferably, in the non-contact power supply facility, the non-contact power receiving apparatus, or the non-contact power supply system, a cooling mechanism for the primary capacitor and / or the secondary capacitor is further provided. The efficiency acquisition unit is configured to sequentially obtain power transmission efficiency during power transmission processing from the non-contact power supply facility to the power receiving device, and the control device further includes a cooling control unit. The cooling control unit is configured to operate the cooling mechanism when the power transmission efficiency falls below a predetermined value during the power transmission process.

  According to the present invention, the temperature of the capacitor can be measured without providing a temperature detecting element such as a thermocouple in the non-contact power feeding by the resonance system to which the coil and the capacitor are connected.

1 is an overall configuration diagram of a non-contact power feeding system according to an embodiment of the present invention. It is a block diagram explaining the control structure for the capacitor | condenser temperature measurement process in the non-contact electric power feeding system shown in FIG. It is a conceptual diagram explaining the temperature characteristic of a capacitor capacity. It is a flowchart explaining the example of the control processing procedure of non-contact electric power feeding by embodiment of this invention. It is a flowchart explaining the detail of the process sequence of a capacitor | condenser temperature measurement process. It is a flowchart explaining the 1st example of the generation conditions of a temperature measurement request | requirement. It is a wave form diagram explaining the example of a change of the capacitor temperature at the time of an electric power feeding process. It is a flowchart explaining the process sequence of the capacitor | condenser temperature measurement process including the variable setting of a temperature measurement interval. It is a flowchart explaining the 2nd example of generation conditions of a temperature measurement request | requirement. It is a schematic block diagram of the hybrid vehicle shown as an example of the electric vehicle carrying the power receiving apparatus shown in FIG.

  Embodiments of the present invention will be described below in detail with reference to the drawings. In the following, the same or corresponding parts in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated in principle.

  FIG. 1 is an overall configuration diagram of a non-contact power feeding system according to an embodiment of the present invention. With reference to FIG. 1, the non-contact power feeding system includes a control device 40, a power feeding facility 100, and a power receiving device 110.

  The power supply facility 100 includes a high frequency power supply device 10, a wattmeter 15, and a coil unit 20.

The high frequency power supply device 10 is connected to the primary coil 25 via the wattmeter 15 and can generate a predetermined high frequency voltage (for example, about several MHz to several tens MHz) based on a drive signal received from the control device 40. The high frequency power supply device 10 is composed of a sine wave inverter circuit, for example, and is controlled by the control device 40.

  The coil unit 20 includes a primary coil 25 and a primary self-resonant coil 30. The coil unit 20 on the primary side constitutes an embodiment of a “power transmission resonator”.

  The primary coil 25 is disposed substantially coaxially with the primary self-resonant coil 30 and is configured to be magnetically coupled to the primary self-resonant coil 30 by electromagnetic induction. The primary coil 25 feeds high-frequency power supplied from the high-frequency power supply device 10 to the primary self-resonant coil 30 by electromagnetic induction.

  The primary self-resonant coil 30 is an LC resonant coil whose both ends are open (not connected), and resonates with a secondary self-resonant coil 70 (described later) of the power receiving device 110 via an electromagnetic field so as not to contact the power receiving device 110. Transmit power. A primary capacitor 35 is connected to the primary self-resonant coil 30. The resonance frequency of the primary self-resonant coil 30 is determined by the inductance of the coil and the capacity of the primary capacitor 35.

  The wattmeter 15 detects power P <b> 1 supplied from the high frequency power supply device 10 to the coil unit 20, i.e., transmission power P <b> 1 transmitted by the power supply facility 100.

  Power receiving device 110 includes a coil unit 60 and a wattmeter 80. The coil unit 60 includes a secondary coil 65 and a secondary self-resonant coil 70. The secondary coil unit 60 constitutes an embodiment of a “power receiving resonator”.

  Similarly to the primary self-resonant coil 30, the secondary self-resonant coil 70 is an LC resonant coil having both ends open. By resonating with the primary self-resonant coil 30 via an electromagnetic field, electric power is supplied from the power supply equipment 100 in a contactless manner. Receive power. Note that a secondary capacitor 75 is connected to the secondary self-resonant coil 70. The resonance frequency of the secondary self-resonant coil 70 is determined by the inductance of the coil and the capacitance of the secondary capacitor 75. By providing the primary capacitor 35 and the secondary capacitor 75 in this way, the resonance frequency can be adjusted precisely compared to the case where only the stray capacitance of the coil is used.

  The secondary coil 65 is disposed substantially coaxially with the secondary self-resonant coil 70 and is configured to be magnetically coupled to the secondary self-resonant coil 70 by electromagnetic induction. The secondary coil 65 is configured to take out the electric power received by the secondary self-resonant coil 70 by electromagnetic induction.

  The wattmeter 80 detects the power P <b> 2 supplied to the coil unit 60, i.e., the power P <b> 2 received by the power receiving device 110.

  The control device 40 is constituted by, for example, a CPU (Central Processing Unit) (not shown) and an electronic control unit (ECU: Electronic Control Unit) with a built-in memory, and based on a map and a program stored in the memory, a predetermined calculation is performed. It is configured to perform processing. Alternatively, at least a part of the ECU may be configured to execute predetermined numerical / logical operation processing by hardware such as an electronic circuit.

  The control device 40 generates a drive signal for controlling the high frequency power supply device 10 and outputs the generated drive signal to the high frequency power supply device 10. Thus, the control device 40 can control the operation and stop of the high-frequency power supply device 10 and the frequency and power value of the output power. That is, the control device 40 controls the power supply from the primary self-resonant coil 30 to the secondary self-resonant coil 70 of the power receiving device 110 by controlling the high-frequency power supply device 10.

  Further, control device 40 receives transmitted power P1 and received power P2 detected by power meters 15 and 80. Instead of the configuration in which the power is directly detected by the wattmeters 15 and 80, the transmission power P1 and / or the reception power P2 may be obtained by arithmetic processing based on the current detection value and the voltage detection value by the current sensor and the voltage sensor. Good.

  The detected temperature Ta by the atmospheric temperature sensor 102 is input to the control device 40. The detected temperature Ta is used for temperature measurement processing of the primary capacitor 35 and the secondary capacitor 75 which will be described later.

  In the configuration example of FIG. 1, the control device 40 is shown as a component that comprehensively controls the power supply facility 100 and the power receiving device 110. However, it is also possible to provide a control part related to the power supply facility 100 in the control device 40 as a component of the power supply facility 100, or to provide a control part related to the power reception device 110 in the control device 40 as a component of the power reception device 110. It is.

  In the non-contact power feeding system shown in FIG. 1, two LC resonance coils having the same natural frequency resonate in an electromagnetic field (near field) in the same manner as two tuning forks resonate. Electric power is transmitted to the other coil via an electromagnetic field.

  Specifically, the power supply facility 100 supplies high-frequency power of a predetermined frequency from the high-frequency power supply device 10 to the primary self-resonant coil 30 that is magnetically coupled to the primary coil 25 by electromagnetic induction. The primary self-resonant coil 30, which is an LC resonator based on the inductance of the coil itself and the capacitance of the primary capacitor 35, has an electromagnetic field (near field) and the secondary self-resonant coil 70 having the same resonance frequency as the primary self-resonant coil 30. Resonates through.

  Then, energy (electric power) moves from the primary self-resonant coil 30 to the secondary self-resonant coil 70 via the electromagnetic field. The energy (electric power) moved to the secondary self-resonant coil 70 is taken out by the secondary coil 65 magnetically coupled to the secondary self-resonant coil 70 by electromagnetic induction and supplied to the load 120.

  In the non-contact power feeding system shown in FIG. 1, the resonance frequency of the primary self-resonant coil 30 and the secondary self-resonant coil 70 is designed to be the same frequency. The resonance frequency preferably matches the frequency of the high-frequency power output from the high-frequency power supply device 10 (power transmission frequency). When the power transmission frequency is away from the resonance frequency, there is a concern that the power transmission efficiency (η = P2 / P1) indicated by the ratio of the received power P2 at the power receiving apparatus to the transmitted power P1 from the power supply facility 100 may decrease.

  In the non-contact power feeding system according to the present invention, by using the above phenomenon, a temperature measurement process for calculating temperature estimated values of the primary self-resonant coil 30 and the secondary self-resonant coil 70 is performed without providing a temperature detecting element. Execute.

  Referring to FIG. 2, primary capacitor 35 is connected to primary self-resonant coil 30 in coil unit 20 of power supply facility 100. The primary capacitor 35 is provided with a heat sink 36, and the primary capacitor 35 can be cooled by the operation of the cooling fan 37. The number of rotations of the cooling fan 37 is controlled by the control device 40.

Similarly, a secondary capacitor 75 is connected to the secondary self-resonant coil 70 in the coil unit 60 of the power receiving device 110. The secondary capacitor 75 is provided with a heat sink 76, and the secondary capacitor 75 can be cooled by the operation of the cooling fan 77. The number of rotations of the cooling fans 37 and 77 is controlled by the control device 40. That is, the cooling fans 37 and 77 are shown as an example of the “cooling mechanism” according to the present invention.

  The control device 40 includes a temperature measurement request generation unit 41, a frequency setting unit 42, an efficiency calculation unit 44, a resonance frequency estimation unit 45, a temperature estimation unit 46, a temperature characteristic storage unit 47, and a cooling control unit 48. The temperature measurement interval setting unit 49 is included. Each of the temperature measurement request generation unit 41, the frequency setting unit 42, the efficiency calculation unit 44, the resonance frequency estimation unit 45, the temperature estimation unit 46, the temperature characteristic storage unit 47, the cooling control unit 48, and the temperature measurement interval setting unit 49. Corresponds to a functional block realized by either software processing by execution of a predetermined program in the control device 40 or hardware processing by construction of a dedicated electronic circuit.

  The temperature measurement request generating unit 41 generates a temperature measurement request for obtaining an estimated temperature value of the primary capacitor 35 and / or the secondary capacitor 75 when a predetermined condition is satisfied. The temperature measurement request generation unit 41 has a timer 43 for timing, and generates a temperature measurement request at the start of power transmission processing or every elapse of a predetermined time during power transmission processing, for example.

  When a capacitor temperature measurement request is generated, the frequency setting unit 42 generates a sweep instruction for changing the power transmission frequency by the high frequency power supply device 10 from a power transmission frequency that is defined in advance corresponding to the resonance frequency. In response to the sweep instruction, the power supply frequency of the high-frequency power supply device 10 is changed in a plurality of stages. For example, according to the sweep instruction, the transmission frequency is set to n stages of f1 to fn (n: integer of 2 or more).

  In response to the sweep instruction from the frequency setting unit 42, the high frequency power supply device 10 changes the power transmission frequency in stages. Then, the power transmission frequency f by the high frequency power supply device 10 is notified to the frequency setting unit 42.

  The efficiency calculating unit 44 calculates the transmission efficiency η (η = P2 / P1) according to the ratio of the received power P2 to the transmitted power P1 during power transmission by the high-frequency power supply device 10. In the configuration example of FIG. 1, the power transmission efficiency η can be calculated based on the detection values of the wattmeters 15 and 80. The efficiency calculation unit 44 is configured to calculate the power transmission efficiency η1 to ηn in each of f1 to fn set stepwise by a sweep instruction.

  The resonance frequency estimation unit 45 acquires the efficiency η1 to ηn at each of the power transmission frequencies f1 to fn from the efficiency calculation unit 44. Then, the resonance frequency estimation unit 45 estimates the resonance frequency fr of the resonance system in correspondence with the highest value among the power transmission efficiencies η1 to ηn. For example, one of the transmission frequencies f1 to fn may be selected as the resonance frequency fr, or the resonance frequency fr may be set as an intermediate value between points f1 to fn in consideration of the transition of the transmission efficiency η1 to ηn. Good.

  The temperature characteristic storage unit 47 stores information on the temperature characteristics of the capacitors 35 and 75. For example, as shown in FIG. 3, the relationship between the change rate (%) of the capacitance with reference to the capacitance at normal temperature (for example, 25 degrees) and the capacitor temperature Tc is preliminarily mapped and stored as a temperature characteristic. . Alternatively, the value of the capacitance C corresponding to the capacitor temperature Tc can be directly stored as a temperature characteristic.

  Note that the information on the temperature characteristics shown in FIG. 3 can be usually acquired as the specification values of the capacitors 35 and 75. Depending on the type of the capacitors 35 and 75, contrary to FIG. 3, there may be a characteristic that the capacity increases as the capacitor temperature Tc increases.

Here, the correspondence between the change in the capacitor temperature Tc and the change in the resonance frequency will be described.
In each of the primary self-resonant coil 30 and the secondary self-resonant coil 70, assuming that the inductance of the coil is L and the capacitances of the capacitors 35 and 75 are C, the resonance frequency fr is expressed by the following equation (1).

fr = 1 / (2π · (L · C) ^1/2 ) (1)
The capacitance C can be calculated backward from the resonance frequency fr according to the following equation (2) obtained by modifying the equation (1).

C = (1 / (2π · fr)) ² · (1 / L) (2)
Here, when the primary self-resonant coil 30 and the secondary self-resonant coil 70 are formed of air-core coils, the temperature characteristic of the inductance L can be ignored when compared with the temperature characteristic of the capacitor C. That is, in the equations (1) and (2), the capacitance C is a variable according to temperature, while the inductance L can be regarded as a constant.

  Therefore, the temperature estimation unit 46 can estimate the capacitor temperature Tc by applying the capacitance C calculated by the equation (2) from the resonance frequency fr obtained by the resonance frequency estimation unit 45 to the characteristics shown in FIG. .

  The temperature estimating unit 46 determines the capacitor temperature Tc according to the ratio of the capacitance C calculated backward from the current resonance frequency to the capacitance C0 (initial value) at the start of power transmission, that is, before the temperature of the capacitors 35 and 75 rises. May be estimated. In this case, the temperature estimation unit 46 regards the temperature Ta detected by the atmospheric temperature sensor 102 as the ambient temperature of the capacitors 35 and 75 before starting the power transmission process. Then, the resonance frequency estimator 45 obtains the resonance frequency f0 (initial value) at that time, and sets the capacitance C calculated backward by Equation (2) as the initial value C0 of the capacitance of the capacitors 35 and 75.

  Then, the relationship between the capacitance C and the resonance frequency fr after being changed by the temperature rise during the power transmission process, and the capacitance (initial value) C0 and the resonance frequency f0 before the temperature rise is based on the equation (2) as follows: It is shown by the formula (3).

C / C0 = (f0 / fr) ² (3)
The initial value f0 of the resonance frequency basically corresponds to the power supply frequency of the high frequency power supply device 10 during power transmission processing. That is, L and C of primary self-resonant coil 30 and secondary self-resonant coil 70 are adjusted so that the resonance frequency of coil units 20 and 60 is essentially the same as the power transmission frequency.

  Therefore, according to the change in the resonance frequency from the initial value f0, the rate of change of the capacitance C is obtained based on the change ratio. Then, the capacitor temperature Tc can be calculated by applying the obtained change rate to the temperature characteristics shown in FIG. Since the resonance frequency of the resonance system (coil units 20 and 60) also changes depending on the state of the coil units 20 and 60 (the positional relationship between the two), based on the rate of change of the resonance frequency fr from the resonance frequency f0 in the initial state. Thus, the estimation accuracy can be improved by back-calculating the rate of change of the capacity C from the initial value C0 and estimating the temperature rise. In other words, when the amount of temperature increase is estimated by directly calculating the capacitance C directly from the resonance frequency fr, the change in the resonance frequency due to the state of the coil units 20 and 60 (the positional relationship between the two) is represented by the capacitor temperature. Although there is a possibility that an error occurs due to detection as a change, such an error can be eliminated if the temperature is estimated based on the rate of change from the initial value.

The cooling control unit 48 controls the operation of the cooling fans 37 and 77 based on the capacitor temperature Tc estimated by the temperature estimation unit 46. Specifically, the cooling controller 48 operates the cooling fans 37 and 77 when the condenser temperature Tc rises above a predetermined temperature. In addition, it is possible to control the amount of air blown (refrigerant amount) by controlling the rotational speed of the cooling fans 37 and 77 according to the temperature rise.

  Next, referring to FIG. 4, a flow chart of the temperature measuring process of the capacitor according to the control configuration shown in FIG. Each step of the flowchart including FIG. 4 is basically realized by software processing by the control device 40, but may be realized by hardware processing.

  Referring to FIG. 4, when instructed to start contactless power feeding, control device 40 activates a series of control processes from step S <b> 100. In step S100, control device 40 acquires initial value T0 of capacitor temperature Tc based on temperature Ta detected by atmospheric temperature sensor 102.

  In step S150, the control device 40 generates a sweep instruction to the high frequency power supply device 10, thereby executing a sweep process for setting the transmission frequency to n stages of f1 to fn. Then, by obtaining the power transmission efficiency η1 to ηn at each of the power transmission frequencies f1 to fn, the power transmission frequency at which the power transmission efficiency becomes the maximum value is acquired as the initial value f0 of the resonance frequency. Furthermore, the initial value C0 of the capacity corresponding to the initial value f0 can be obtained from the equation (2). Thus, steps S100 and S150 are executed at the start of non-contact power feeding.

  Further, when the initial processing in steps S100 and S150 ends, the control device 40 starts actual power transmission processing in step S200. In this power transmission process, high-frequency power is output from the high-frequency power supply device 10 at a specified power transmission frequency and power value. Then, by magnetic resonance between the primary self-resonant coil 30 and the secondary self-resonant coil 70, non-contact power transmission is performed from the high frequency power supply device 10 to the load 120.

  The control device 40 determines whether or not a condenser temperature measurement request is generated in step S300 during execution of the power transmission process. The temperature measurement request is generated, for example, at regular time intervals during the power transmission process.

  When a temperature measurement request is generated (YES determination in S300), control device 40 performs condenser temperature measurement processing in step S400. On the other hand, when the temperature measurement request is not generated (NO determination in S300), the condenser temperature measurement process in step S400 is not executed.

  Furthermore, during normal power transmission in step S300, the control device 40 sequentially determines whether or not the power transmission end condition is ended in step S500. The power transmission end condition is established in response to, for example, a power transmission completion instruction (switch-off) by the user. Alternatively, when load 120 (FIG. 1) includes a power storage device (not shown) and non-contact power feeding is performed for charging the power storage device, a power transmission termination condition is established in response to the completion of charging. Also good. Alternatively, when it is detected that power transmission is impossible due to the positional relationship between the power supply facility 100 (primary self-resonant coil 30) and the power receiving device 110 (secondary self-resonant coil 70), the power transmission end condition is automatically set. It may be established.

  Control device 40 continues the power transmission process in response to the condenser temperature measurement request by repeatedly executing steps S300 and S400 until the power transmission termination condition is satisfied (NO determination in S500). On the other hand, when the power transmission end condition is satisfied (when YES is determined in S500), control device 40 ends the power transmission process in step S600.

FIG. 5 shows details of the processing procedure of the condenser temperature measurement process in step S400 of FIG.

  Referring to FIG. 5, when the condenser temperature measurement process is started, control device 40 starts a frequency sweep by generating a sweep instruction to high-frequency power supply device 10 in step S410. In step S420, control device 40 sets the power transmission frequency of high-frequency power supply device 10 so as to change the power transmission frequency to n stages of f1 to fn according to a predetermined pattern.

  In step S430, control device 40 calculates power transmission efficiency η = P2 / P1 at the power transmission frequency set in step S420. Then, in step S440, control device 40 determines whether or not the power transmission efficiency has been calculated for each of the predetermined pattern, that is, the predetermined power transmission frequencies f1 to fn. By repeatedly executing steps S420 and S430 until YES is determined in step S440, power transmission efficiencies η1 to ηn at each of the predetermined power transmission frequencies f1 to fn are acquired.

  When power transmission efficiency η1 to ηn is acquired by the end of the predetermined pattern (when YES is determined in S440), control device 40 determines resonance frequency fr according to the power transmission frequency at which efficiency is maximized in step S450. The processing in step S450 is equivalent to the function of the resonance frequency estimation unit 45 shown in FIG.

  Further, in step S460, control device 40 estimates capacitance C of capacitors 35 and 75 based on resonance frequency fr. As described above, it is preferable to calculate the rate of change from the initial value C0 for the capacitor C based on the rate of change of the resonance frequency with respect to the initial value f0.

  In step S470, the control device 40 refers to the information stored in the temperature characteristic storage unit 47 of FIG. 2 to determine the capacity C calculated in step S460 or the rate of change (C / C0) of the capacity C as the temperature characteristic. To estimate the capacitor temperature Tc.

  In step S480, control device 40 performs cooling control of capacitors 35 and 75 based on the estimated temperature value calculated in step S470. For example, the operation / stop of the cooling fans 37 and 77 and the number of rotations of the cooling fan during operation (that is, the refrigerant amount) are controlled.

  As described above, according to the present embodiment, the temperature of the capacitors 35 and / or 75 is controlled only by controlling the components originally necessary for the non-contact power feeding without providing the capacitors 35 and 75 with a temperature detecting element such as a thermocouple. An estimated temperature measurement process can be executed. In addition, since it is estimated that power transmission efficiency will fall at the time of a capacitor | condenser temperature measurement process, you may reduce the output electric power of the high frequency power supply device 10 rather than a normal power transmission process.

  Further, the cooling mechanism (cooling fans 37 and 77) of the capacitors 35 and 75 can be controlled based on the estimated capacitor temperature. When it is determined that the capacitor temperature Tc is excessively increased, the transmitted power may be decreased below the normal value or the power transmission process may be stopped in order to prevent further temperature increase.

Further, the power transmission frequency in the normal power transmission process (S200) to be resumed after the capacitor temperature measurement process may be adjusted according to the current resonance frequency fr obtained in the capacitor temperature measurement process. That is, when the currently used power transmission frequency is different from the obtained resonance frequency fr, the power transmission frequency may be changed so as to approach the resonance frequency fr. In this way, the efficiency of the power transmission process can be ensured by following the change in the resonance frequency due to the change in the capacitor temperature. For example, such adjustment of the power transmission frequency can be executed by the frequency setting unit 42 of FIG.

  Next, some examples of conditions for generating a condenser temperature measurement request during power transmission processing will be described.

  FIG. 6 is a flowchart illustrating a first example of conditions for generating a temperature measurement request. The flowchart of FIG. 6 further explains step S300 of FIG.

  Referring to FIG. 6, in step S310, control device 40 updates the time value measured by the timer at a predetermined cycle, and in step S320, the updated time value has elapsed by ΔTm from the end of the previous condenser temperature measurement. Determine whether or not. Then, control device 40 repeats the timer timing in step S310 until ΔTm elapses (NO in S320).

  When the measured value reaches ΔTm (when YES is determined in S320), control device 40 proceeds to step S330 and generates a condenser temperature measurement request.

  The temperature measuring interval ΔTm of the condenser is simply fixed to a predetermined value. In this case, during the power transmission process (S200 in FIG. 4), the condenser temperature measurement process (S400) is executed every time a predetermined time elapses.

  On the other hand, during the condenser temperature measurement process, there is a concern that the power transmission efficiency is lowered because the power transmission frequency is changed. Therefore, it is preferable to keep the temperature measuring process of the capacitor during the power transmission process to the minimum necessary.

  FIG. 7 is a waveform diagram for explaining an example of a change in capacitor temperature during power supply processing. If the temperature measurement interval ΔTm is variably set according to the characteristics of such temperature change, the number of times can be suppressed while effectively performing the temperature measurement process of the capacitor.

  Referring to FIG. 7, capacitor temperature Tc generally increases with a first-order lag with respect to initial value T0 at the start of power transmission.

  Therefore, the rate of change of the capacitor temperature Tc (temperature increase slope: ΔTc / t) is large immediately after the start of power transmission processing, but decreases with time. Accordingly, by setting the temperature measurement interval ΔTm variably according to the temperature change rate, it is possible to efficiently provide a temperature measuring instrument opportunity for the condenser.

  For example, each time the condenser temperature measurement process is completed, the temperature change rate (ΔTc / t) can be calculated based on the current temperature estimation value, and the temperature measurement interval ΔTm can be set to be inversely proportional to the temperature change rate. In this way, it is possible to generate a temperature measurement request so that the temperature measurement interval ΔTm is shortened when the temperature change rate is large, and conversely, when the temperature change rate is small, the temperature measurement interval ΔTm is lengthened.

FIG. 8 shows the process of step S400 in this case.
Referring to FIG. 8, control device 40 calculates an estimated value of capacitor temperature Tc in response to the generation of the capacitor temperature measurement request in accordance with the processing of steps S <b> 410 to S <b> 470 shown in FIG. 5. In step S490, control device 40 obtains the rate of change of capacitor temperature Tc from the calculated temperature estimated value, and sets interval ΔTm until the next capacitor temperature measurement process according to this temperature change rate. In this way, the next step S300 in FIG. 4 (S310 to S330 in FIG. 6) is processed in accordance with the temperature measurement interval ΔTm set in S490.

  Referring to FIG. 7 again, after the start of the power transmission process, when the capacitor temperature measurement process is executed at time t1 according to the initial value of ΔTm, based on the temperature change rate obtained from the initial value T0 and the estimated capacitor temperature Tc, A temperature measurement interval ΔTm is set. Then, at the time t2 when the temperature measurement interval ΔTm set in the temperature measurement process at the time t1 has elapsed from the time t1, the next condenser temperature measurement request is generated. At the end of the temperature measurement process at time t1, the temperature measurement interval ΔTm is updated. Hereinafter, from time t3 to t8, the temperature measurement interval ΔTm can be set gradually longer according to the temperature change rate based on the estimated value of the capacitor temperature Tc at each timing. It should be noted that even after the temperature rise once becomes moderate, if the temperature rise becomes large for some reason, it is understood that the temperature measurement interval ΔTm until the next time is set to be short again accordingly.

  As described above, by setting the temperature measurement interval ΔTm variably in accordance with the temperature change rate for each temperature measurement process of the capacitor, it is possible to efficiently provide a temperature measurement opportunity for the capacitor.

  FIG. 9 is a flowchart illustrating a second example of conditions for generating a temperature measurement request. FIG. 9 also explains step S300 of FIG. 4 further.

  Referring to FIG. 9, in step S <b> 315, control device 40 calculates power transmission efficiency (P2 / P1) during power transmission processing. In step S325, the control device 40 determines whether or not the power transmission efficiency η calculated in step S315 is lower than the predetermined value η0.

  When η <η0 (when YES is determined in S325), control device 40 generates a temperature measurement request for the capacitor in step S335. On the other hand, when η ≧ η0 (when NO is determined in S325), S330 is skipped, so that a temperature measurement request for the capacitor is not generated.

  As described above, when the capacitor temperature changes (increases), the resonance frequency fr of the resonance system changes greatly, and the power transmission efficiency η (P2 / P1) decreases. For this reason, when the power transmission efficiency is significantly reduced during the power transmission process, there is a concern about a large change in the capacitor temperature. Therefore, while calculating the power transmission efficiency sequentially during the power transmission process and generating a capacitor temperature measurement request in response to a decrease in the power transmission efficiency, it is possible to efficiently provide a capacitor temperature measurement opportunity.

  When there is a significant decrease in power transmission efficiency, there is a concern that a large temperature change (rise) has already occurred. Therefore, in the process of step S330, wait for the estimation of the capacitor temperature in response to the temperature measurement request. Alternatively, the cooling fans 37 and 77 may be operated. Alternatively, the transmitted power may be reduced or the power transmission process may be stopped.

  6 and 9 may be combined to generate a temperature measurement request for the capacitor in response to both the elapse of the temperature measurement interval ΔTm and the decrease in power transmission efficiency.

(Application example to electric vehicles)
FIG. 10 is a configuration diagram of a hybrid vehicle shown as an example of an electric vehicle on which the power receiving device 110 shown in FIG. 1 is mounted.

Referring to FIG. 10, hybrid vehicle 200 includes power storage device 210, system main relay SMR, boost converter 220, inverters 230 and 232, motor generators 240 and 242, engine 250, and power split device 260. Drive wheel 270. Hybrid vehicle 200 further includes a coil unit 60, a power meter 80, a charger 280, a charging relay CHR, and a vehicle ECU 290. Coil unit 6
0 includes a secondary coil 65 and a secondary self-resonant coil 70.

  Hybrid vehicle 200 includes engine 250 and motor generator 242 as power sources. Engine 250 and motor generators 240 and 242 are connected to power split device 260. Hybrid vehicle 200 travels by driving force generated by at least one of engine 250 and motor generator 242. The power generated by the engine 250 is divided into two paths by the power split device 260. That is, one is a path transmitted to the drive wheel 270 and the other is a path transmitted to the motor generator 240.

  Motor generator 240 is an AC rotating electric machine, and includes, for example, a three-phase AC synchronous motor in which a permanent magnet is embedded in a rotor. Motor generator 240 generates power using the kinetic energy of engine 250 via power split device 260. For example, when the state of charge of power storage device 210 (also referred to as “SOC (State Of Charge)”) becomes lower than a predetermined value, engine 250 is started and power is generated by motor generator 240 to store power. Device 210 is charged.

  The motor generator 242 is also an AC rotating electric machine, and, like the motor generator 240, is composed of, for example, a three-phase AC synchronous motor in which a permanent magnet is embedded in a rotor. Motor generator 242 generates driving force using at least one of the electric power stored in power storage device 210 and the electric power generated by motor generator 240. Then, the driving force of motor generator 242 is transmitted to driving wheel 270.

  In addition, when braking the vehicle or reducing acceleration on a downward slope, mechanical energy stored in the vehicle as kinetic energy or positional energy is used for rotational driving of the motor generator 242 via the drive wheels 270, so that the motor generator 242 Operates as a generator. Thereby, motor generator 242 operates as a regenerative brake that converts running energy into electric power and generates braking force. The electric power generated by motor generator 242 is stored in power storage device 210.

  Power split device 260 includes a planetary gear including a sun gear, a pinion gear, a carrier, and a ring gear. The pinion gear engages with the sun gear and the ring gear. The carrier supports the pinion gear so as to be capable of rotating, and is connected to the crankshaft of engine 250. The sun gear is coupled to the rotation shaft of motor generator 240. The ring gear is connected to the rotating shaft of motor generator 242 and drive wheel 270.

  System main relay SMR is arranged between power storage device 210 and boost converter 220 and electrically connects power storage device 210 to boost converter 220 in accordance with a signal from vehicle ECU 290. Boost converter 220 performs DC voltage conversion between the voltage on positive line PL1 connected to power storage device 210 and the voltage on positive line PL2. Boost converter 220 is formed of, for example, a DC chopper circuit, and can control the voltage of positive line PL2 to be higher than the voltage of positive line PL1. Inverters 230 and 232 drive motor generators 240 and 242, respectively. Inverters 230 and 232 are formed of, for example, a three-phase bridge circuit.

The correspondence relationship between FIG. 1 and FIG. 10 will be described. The power receiving device 110 (FIG. 1) according to this embodiment, that is, the coil unit 60 (secondary coil 65, secondary self-resonant coil 70, and second A secondary capacitor 75) and a power meter 80 are mounted. The charger 280 to the power storage device 210 correspond to the load 120 in FIG. Since the configuration and operation of power reception device 110 are the same as described above, detailed description thereof will not be repeated.

  Charger 280 is a power converter configured to convert AC power extracted by secondary coil 65 into charging power for power storage device 210. Charging relay CHR is arranged between charger 280 and power storage device 210, and electrically connects charger 280 and power storage device 210 in accordance with a signal from vehicle ECU 290.

  In the traveling mode, vehicle ECU 290 turns on system main relay SMR and turns off charging relay CHR. Then, vehicle ECU 290 generates signals for driving boost converter 220 and motor generators 240 and 242 based on signals from the accelerator opening, vehicle speed, and other various sensors when the vehicle is running, The signal is output to boost converter 220 and inverters 230 and 232.

  Further, the vehicle ECU 290 has a communication function with the control device 40 of the power supply facility 100. That is, the received power P <b> 2 detected by the wattmeter 80 can be transmitted to the control device 40. Alternatively, data and signals may be directly exchanged between the power receiving device 110 and the control device 40 without using the vehicle ECU 290. Further, it is possible to incorporate the function of the control device 40 into the vehicle ECU 290 while providing a communication function with the power supply facility 100.

  When power is supplied from power supply facility 100 (FIG. 1) to hybrid vehicle 200, vehicle ECU 290 turns on charge relay CHR. The system main relay SMR is basically turned off, but may be turned on as necessary.

  Thereby, power storage device 210 can be charged with the power received by secondary self-resonant coil 70. At that time, the controller 40 can monitor the temperature rise of the secondary capacitor 75 during charging. In particular, it becomes possible to control the cooling mechanism (for example, the cooling fan 77 of FIG. 2) and the charging relay CHR of the secondary capacitor 75 based on information on the capacitor temperature Tc from the control device 40.

  Further, by adjusting the power transmission frequency from the power supply facility 100 based on the measurement of the resonance frequency during the capacitor temperature measurement process, the power storage device 210 can be charged by non-contact power supply while ensuring the power transmission efficiency.

  It is also possible to receive power from power supply facility 100 while the vehicle is running by turning on both system main relay SMR and charging relay CHR.

  Further, in the above, as an example of an electric vehicle equipped with power receiving device 110, a series / parallel type hybrid vehicle capable of dividing the power of engine 250 by power split device 260 and transmitting it to drive wheels 270 and motor generator 240. However, the present invention is also applicable to other types of hybrid vehicles.

  For example, the engine 250 is used only for driving the motor generator 240 and the driving force of the vehicle is generated only by the motor generator 242, so-called series type hybrid vehicle, or only regenerative energy among the kinetic energy generated by the engine 250 is used. The present invention can also be applied to a hybrid vehicle that is recovered as electric energy, a motor-assist type hybrid vehicle in which a motor assists the engine as the main power if necessary. In addition, the present invention can be applied to an electric vehicle that does not include engine 250 and travels only by electric power, and a fuel cell vehicle that further includes a fuel cell as a DC power supply in addition to power storage device 210.

  As described above, in the non-contact power supply system according to the embodiment of the present invention, the capacitor 35, 75 is not provided with a temperature detection element such as a thermocouple, and only by controlling the components that are originally necessary for non-contact power supply. A temperature measurement process that estimates the temperature of 35 and / or 75 can be performed.

  In particular, by estimating the change in the capacitor temperature Tc based on the change rate with respect to the initial value of the capacitor temperature and the resonance frequency during the power transmission start process, the power transmission starts depending on the state of the coil units 20 and 60 (the positional relationship between them). Even when the resonance frequency deviates from the original value from time, the temperature estimation error can be suppressed.

  Further, based on the temperature estimation result, it is possible to secure the transmission efficiency by controlling the cooling mechanism of the capacitors 35 and 75 and adjusting the transmission frequency.

  In the above embodiment, power is supplied to the primary self-resonant coil 30 by electromagnetic induction using the primary coil 25, and electric power is taken out from the secondary self-resonant coil 70 by electromagnetic induction using the secondary coil 65. However, the primary self-resonant coil 30 may be directly supplied with power from the high-frequency power supply device 10 without providing the primary coil 25, and the power may be directly taken out from the secondary self-resonant coil 70 without providing the secondary coil 65. That is, the primary side coil unit 20 (power transmission resonator) is configured by only the primary self-resonant coil 30, and the secondary side coil unit 60 (power receiving resonator) is configured by only the secondary self-resonant coil 70. Also good.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  The present invention can be applied to non-contact power feeding by resonance via an electromagnetic field between a power transmission side and a power reception side.

10 High frequency power supply, 15, 80 Wattmeter, 20 Coil unit (primary side), 25
Primary coil, 30 Primary self-resonant coil, 35 Primary capacitor, 36, 76 Heat sink, 37, 77 Cooling fan, 40 Control device, 41 Temperature measurement request generation unit, 42 Frequency setting unit, 43 Timer, 44 Efficiency calculation unit, 45 Resonance Frequency estimation unit, 46 Temperature estimation unit, 47 Temperature characteristic storage unit, 48 Cooling control unit, 49 Temperature measurement interval setting unit, 60 Coil unit, 65 Secondary coil, 70 Secondary self-resonant coil, 75 Secondary capacitor, 100
Power supply equipment, 102 atmospheric temperature sensor, 110 power receiving device, 120 load, 200 hybrid vehicle, 210 power storage device, 220 boost converter, 230, 232 inverter, 240, 242 motor generator, 250 engine, 260 power split device, 270 drive wheel, 280 Charger, 290 Vehicle ECU, C0 Initial value (capacity), CHR
Charging relay, f power transmission frequency, f0 initial value (resonance frequency), fr resonance frequency, P1
Transmission power, P2 received power, PL1, PL2 positive line, SMR system main relay, T0 initial value (capacitor temperature), Ta detection temperature (atmospheric temperature), Tc capacitor temperature, ΔTm temperature measurement interval, η Transmission efficiency.

Claims (18)

A power supply configured to generate high frequency power at a controllable frequency;
A power transmission resonator for transmitting power from the power supply device to the power reception device in a contactless manner by resonating with a power reception resonator of the power reception device via an electromagnetic field;
A control device for controlling the power supply device and the power transmission resonator,
The power transmission resonator includes:
A primary self-resonant coil configured to generate the electromagnetic field by being fed with the high-frequency power;
A primary capacitor connected to the primary self-resonant coil;
The controller is
A temperature measurement requesting unit for generating a temperature measurement request of the primary capacitor when a predetermined condition is satisfied;
An efficiency acquisition unit for obtaining power transmission efficiency from the power transmission resonator to the power reception resonator;
At the time of the temperature measurement request, a frequency setting unit for changing the frequency of the power supply device in a plurality of stages,
An information storage unit for storing information about the temperature characteristics of the capacitance of the primary capacitor;
A frequency estimation unit for estimating a resonance frequency of the power transmission resonator based on the power transmission efficiency in each of the plurality of stages acquired by the efficiency acquisition unit at the time of the temperature measurement request;
Based on the estimated resonance frequency and the capacitance of the primary capacitor estimated from the inductance of the primary self-resonant coil, and the information stored in the information storage unit, the temperature estimation value of the primary capacitor is calculated. A non-contact power supply facility including a temperature estimation unit. The temperature measurement request includes a first request generated at the start of power transmission processing from the contactless power supply facility to the power receiving device, and a second request generated during the power transmission processing,
The frequency setting unit is configured to change the frequency of the power supply device from a predetermined power transmission frequency to a plurality of stages in response to each of the first and second requests,
The frequency estimation unit estimates an initial value of the resonance frequency based on the power transmission efficiency at each of the plurality of stages at the time of the first request, and at each of the plurality of stages at the time of the second request. Estimating the current value of the resonance frequency based on power transmission efficiency,
The temperature estimation unit obtains an initial temperature of the primary capacitor based on an ambient temperature at the time of the first request, and estimates from a relationship between the initial value and the current value of the resonance frequency at the time of the second request. The non-contact power feeding equipment according to claim 1, wherein the estimated temperature value is calculated based on a change in the capacity of the primary capacitor, the initial temperature, and the information stored in the information storage unit. The controller is
When the temperature estimation value is calculated by the temperature estimation unit in response to the temperature measurement request, a temperature measurement interval setting unit for variably setting the temperature measurement interval according to the temporal transition of the temperature estimation value thus far Further including
The non-contact power supply facility according to claim 1, wherein the temperature measurement requesting unit generates the next temperature measurement request when the temperature measurement interval elapses from the generation of the current temperature measurement request. A cooling mechanism for the primary capacitor;
The controller is
The non-control unit according to any one of claims 1 to 3, further comprising a cooling control unit configured to control an operation of the cooling mechanism based on the temperature estimated value calculated by the temperature estimating unit. Contact power supply equipment. The efficiency acquisition unit is configured to sequentially obtain the power transmission efficiency during power transmission processing from the non-contact power feeding facility to the power receiving device,
The non-contact according to any one of claims 1 to 3, wherein the temperature measurement request unit is configured to generate the temperature measurement request when the power transmission efficiency falls below a predetermined value during the power transmission process. Power supply equipment. The non-contact power supply facility is:
A cooling mechanism for the primary capacitor;
The efficiency acquisition unit is configured to sequentially obtain the power transmission efficiency during power transmission processing from the non-contact power feeding facility to the power receiving device,
The controller is
The non-contact power feeding facility according to claim 1, further comprising a cooling control unit configured to operate the cooling mechanism when the power transmission efficiency falls below a predetermined value during the power transmission process. . Receiving power transmitted from the power transmission resonator in a contactless manner by resonating with a power transmission resonator configured to generate high frequency power at a controllable frequency via an electromagnetic field with a power transmission resonator. A power receiving resonator,
A control device for controlling the power supply device and the power receiving resonator,
The power receiving resonator includes:
A secondary self-resonant coil configured to receive power from the primary self-resonant coil in a non-contact manner by resonating with a primary self-resonant coil of the power transmission resonator via the electromagnetic field;
A secondary capacitor connected to the secondary self-resonant coil,
The controller is
A temperature measurement requesting unit for generating a temperature measurement request of the secondary capacitor when a predetermined condition is satisfied;
An efficiency acquisition unit for obtaining power transmission efficiency from the power transmission resonator to the power reception resonator;
At the time of the temperature measurement request, a frequency setting unit that changes the frequency of the power supply device from a predetermined power transmission frequency to a plurality of stages;
An information storage unit for storing information about the temperature characteristics of the capacitance of the secondary capacitor;
A frequency estimation unit for estimating a resonance frequency of the power receiving resonator based on the power transmission efficiency in each of the plurality of stages acquired by the efficiency acquisition unit at the time of the temperature measurement request;
Based on the estimated resonance frequency and the capacitance of the secondary capacitor estimated from the inductance of the secondary self-resonant coil, and the information stored in the information storage unit, the estimated temperature value of the secondary capacitor A non-contact power receiving device including a temperature estimation unit for calculating The temperature measurement request includes a first request generated at the start of power transmission processing from the power receiving resonator to the non-contact power receiving device, and a second request generated during the power transmission processing. Including
The frequency setting unit is configured to change the frequency of the power supply device from a predetermined power transmission frequency to a plurality of stages in response to each of the first and second requests,
The frequency estimation unit estimates an initial value of the resonance frequency based on the power transmission efficiency at each of the plurality of stages at the time of the first request, and at each of the plurality of stages at the time of the second request. Estimating the current value of the resonance frequency based on power transmission efficiency,
The temperature estimation unit obtains an initial temperature of the secondary capacitor based on an ambient temperature at the time of the first request, and from the relationship between the initial value and the current value of the resonance frequency at the time of the second request. The contactless power receiving device according to claim 7, wherein the estimated temperature value is calculated based on the estimated change in the capacitance of the secondary capacitor, the initial temperature, and the information stored in the information storage unit. . The controller is
When the temperature estimation value is calculated by the temperature estimation unit in response to the temperature measurement request, a temperature measurement interval setting unit for variably setting the temperature measurement interval according to the temporal transition of the temperature estimation value thus far Further including
The non-contact power receiving apparatus according to claim 7 or 8, wherein the temperature measurement requesting unit generates the next temperature measurement request when the temperature measurement interval has elapsed since the current temperature measurement request is generated. A cooling mechanism for the secondary capacitor;
The controller is
The non-control unit according to any one of claims 7 to 9, further comprising a cooling control unit configured to control an operation of the cooling mechanism based on the temperature estimated value calculated by the temperature estimating unit. Contact power receiving device. The efficiency acquisition unit is configured to sequentially obtain the power transmission efficiency during power transmission processing from the power transmission resonator to the power reception resonator,
The non-contact according to any one of claims 7 to 9, wherein the temperature measurement request unit is configured to generate the temperature measurement request when the power transmission efficiency falls below a predetermined value during the power transmission process. Power receiving device. The non-contact power receiving device is:
A cooling mechanism for the secondary capacitor;
The efficiency acquisition unit is configured to sequentially obtain the power transmission efficiency during power transmission processing from the power transmission resonator to the power reception resonator,
The controller is
The contactless power receiving device according to any one of claims 7 to 9, further comprising a cooling control unit configured to operate the cooling mechanism when the power transmission efficiency falls below a predetermined value during the power transmission process. . A power supply facility for transmitting high-frequency power;
A power receiving device for receiving power transmitted from the power supply facility in a contactless manner;
A control device for controlling the power supply equipment and the power receiving device,
The power supply equipment is
A power supply device configured to generate the high-frequency power by a controllable frequency;
A power transmission resonator for transmitting the high-frequency power from the power supply device to the power receiving device in a contactless manner by resonating via an electromagnetic field;
The power transmission resonator includes:
A primary self-resonant coil configured to generate the electromagnetic field by being fed with the high-frequency power;
A primary capacitor connected to the primary self-resonant coil;
The power receiving device is:
Including a power receiving resonator for receiving power transmitted from the power transmitting resonator in a contactless manner;
The power receiving resonator includes:
A secondary self-resonant coil configured to receive power from the primary self-resonant coil in a non-contact manner by resonating with a primary self-resonant coil of the power transmission resonator via the electromagnetic field;
A secondary capacitor connected to the secondary self-resonant coil;
The controller is
A temperature measurement requesting unit for generating a temperature measurement request for the primary and secondary capacitors when a predetermined condition is satisfied;
An efficiency acquisition unit for obtaining power transmission efficiency from the power transmission resonator to the power reception resonator;
At the time of the temperature measurement request, a frequency setting unit that changes the frequency of the power supply device from a predetermined power transmission frequency to a plurality of stages;
An information storage unit for storing information about the temperature characteristics of the capacities of the primary and secondary capacitors;
A frequency estimation unit for estimating a resonance frequency of the power transmission resonator and the power reception resonator based on the power transmission efficiency in each of the plurality of stages acquired by the efficiency acquisition unit at the time of the temperature measurement request;
Based on the estimated resonance frequency and the capacities of the primary and secondary capacitors estimated from the inductances of the primary and secondary self-resonant coils, and the information stored in the information storage unit, the primary and secondary A non-contact power feeding system including a temperature estimating unit for calculating a temperature estimated value of the secondary capacitor. The temperature measurement request includes a first request generated at the start of power transmission processing from the power supply facility to the power receiving device, and a second request generated in the middle of the power transmission processing,
The frequency setting unit is configured to change the frequency of the power supply device from a predetermined power transmission frequency to a plurality of stages in response to the first and second requests,
The frequency estimation unit estimates an initial value of the resonance frequency based on the power transmission efficiency at each of the plurality of stages at the time of the first request, and at each of the plurality of stages at the time of the second request. Estimating the current value of the resonance frequency based on power transmission efficiency,
The temperature estimating unit obtains initial temperatures of the primary and secondary capacitors based on an ambient temperature at the time of the first request, and at the time of the second request, the initial value and the current value of the resonance frequency are obtained. The temperature estimated value is calculated based on a change in capacitance of the primary and secondary capacitors estimated from a relationship, the initial temperature, and the information stored in the information storage unit. Contactless power supply system. The controller is
When the temperature estimation value is calculated by the temperature estimation unit in response to the temperature measurement request, a temperature measurement interval setting unit for variably setting the temperature measurement interval according to the temporal transition of the temperature estimation value so far In addition,
The non-contact power feeding system according to claim 13 or 14, wherein the temperature measurement requesting unit generates the next temperature measurement request when the temperature measurement interval elapses from the generation of the current temperature measurement request. The non-contact power feeding system further includes a cooling mechanism for the primary and secondary capacitors,
The controller is
The non-control unit according to any one of claims 13 to 15, further comprising a cooling control unit configured to control an operation of the cooling mechanism based on the temperature estimated value calculated by the temperature estimating unit. Contact power supply system. The efficiency acquisition unit is configured to sequentially obtain the power transmission efficiency during power transmission processing from the power supply facility to the power receiving device,
The temperature measurement request unit is configured to generate the temperature measurement request when the power transmission efficiency falls below a predetermined value during the power transmission process.
The non-contact electric power feeding system of any one of Claims 13-15. The non-contact power feeding system further includes a cooling mechanism for the primary and secondary capacitors,
The efficiency acquisition unit is configured to sequentially obtain the power transmission efficiency during power transmission processing from the power supply facility to the power receiving device,
The controller is
A cooling control unit configured to operate the cooling mechanism when the power transmission efficiency falls below a predetermined value during the power transmission process;
The non-contact electric power feeding system of any one of Claims 13-15.

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