JP2013223301A - Power reception device and power transmission device of contactless power transfer unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power reception device and a power transmission device of a contactless power transfer unit that enable contactless power transfer, which enable preferable power transfer even if specification differs between both devices.SOLUTION: A contactless power transfer unit 10 comprises a ground side device 11 disposed on the ground and a vehicle-side device 21 mounted on a vehicle. In the ground side device 11 are disposed a high frequency power source 12 and a power transmission device 13 having a primary side coil 13a. In the vehicle-side device 21 are disposed a power reception device 23 having a secondary side coil 23a that enables magnetic resonance with the primary side coil 13a and an automotive battery 22 to be charged by using a high frequency power received by the power reception device 23. A vehicle-side controller 27 disposed in the vehicle-side device 21, on the basis of a comparison result of a transmitting efficiency and a threshold efficiency, determines transfer to a charge sequence and modifies the threshold efficiency according to identification information of the ground side device 11.

Description

  The present invention relates to a power receiving device and a power transmission device of a non-contact power transmission apparatus.

  2. Description of the Related Art Conventionally, as a non-contact power transmission device that does not use a power cord or a power transmission cable, for example, a device using magnetic field resonance is known. For example, the non-contact power transmission device of Patent Literature 1 includes a power transmission device provided with an AC power source and a primary resonance coil to which AC power is input from the AC power source. Further, a vehicle as a power receiving device is provided with a primary resonance coil and a secondary resonance coil capable of magnetic field resonance. Then, AC power is transmitted from the power transmitting device to the vehicle by magnetic resonance between the primary resonance coil and the secondary resonance coil. The transmitted AC power is rectified to DC power by a rectifier provided in the vehicle and input to the vehicle battery. Thereby, the vehicle battery is charged.

JP 2009-106136 A

  In the non-contact power transmission device, in order to avoid power transmission in a mode in which the transmission efficiency is excessively low, power transmission is continued when the transmission efficiency is higher than the threshold efficiency, and the transmission efficiency is higher than the threshold efficiency. If it is too low, it is conceivable to stop power transmission. In this case, since the non-contact power transmission apparatus is usually configured by a power receiving device and a power transmission device having the same specification (version), the threshold efficiency is set based on the power reception device and the power transmission device having the same specification (version). Can be considered. However, in reality, there may be a case where there are a plurality of types of power receiving devices and power transmitting devices having different specifications, and power is transmitted between the two having different specifications. For this reason, the configuration using the threshold efficiency set based on the power receiving device and the power transmission device having the same specification is insufficient for the continuation determination of the power transmission.

  An object of the present invention is made in view of the above-described circumstances, and in a power receiving device and a power transmitting device of a non-contact power transmission device capable of non-contact power transmission, even if the specifications are different between the two. An object of the present invention is to provide a power receiving device and a power transmitting device that can suitably perform power transmission.

  In order to achieve the above object, the invention according to claim 1, when the transmission efficiency is higher than a predetermined threshold efficiency, the power transmission between the power transmitting device and the power receiving device is continued, and the transmission efficiency is A power receiving device of a non-contact power transmission device that stops power transmission when lower than the threshold efficiency, and a secondary coil capable of receiving AC power from a primary coil provided in the power transmitting device; And an input unit capable of inputting information related to the power transmission device, and a changing means for changing the threshold efficiency based on the information related to the power transmission device input to the input unit. According to this invention, power transmission is not performed in a mode in which the transmission efficiency is lower than the threshold efficiency. Thereby, the power transmission in a mode with a large power loss can be suppressed.

  Here, the maximum transmission efficiency in the non-contact power transmission apparatus varies according to the specifications of the power transmitting device and the power receiving device. For this reason, depending on the power transmission device, the threshold efficiency may become excessively high or low with respect to the maximum transmission efficiency.

  On the other hand, according to the present invention, the threshold efficiency corresponding to the maximum transmission efficiency determined in relation to the power transmission device can be obtained by changing the threshold efficiency based on the information related to the power transmission device. Thereby, even if it is a case where the specification of power transmission equipment differs, it can be judged suitably whether electric power transmission is continued.

  The invention according to claim 2 is configured such that the input unit is capable of inputting information relating to the power transmission device and information relating to transmission power measured by the power transmission device, and measuring the transmission power and itself. And calculating means for calculating the transmission efficiency based on the received power. According to this invention, it is possible to compare the transmission efficiency and the threshold efficiency by calculating the transmission efficiency based on the transmitted power and the received power input to the input unit. In addition, the power receiving device can change the threshold efficiency, calculate the transmission efficiency, and compare the two, so that the devices that execute each process can be unified. Therefore, simplification of control can be achieved.

  The “received power” includes, for example, a secondary coil in a configuration including a rectifier that rectifies AC power received by a secondary coil into DC power and a load to which DC power is input. AC power received at, or DC power input to a load can be considered.

  When the transmission efficiency is higher than a predetermined threshold efficiency, power transmission between the power transmitting device and the power receiving device is continued, and the transmission efficiency is lower than the threshold efficiency. Is a power transmission device of the non-contact power transmission device that stops the power transmission, and transmits the AC power in a contactless manner to an AC power source that outputs AC power and a secondary coil provided in the power receiving device. A primary coil that can be input; an input unit that can input information about the power receiving device; and a changing unit that changes the threshold efficiency based on information about the power receiving device input to the input unit. It is characterized by that. According to this invention, power transmission is not performed in a mode in which the transmission efficiency is lower than the threshold efficiency. Thereby, the power transmission in a mode with a large power loss can be suppressed.

  Here, the maximum transmission efficiency in the non-contact power transmission apparatus varies according to the specifications of the power transmitting device and the power receiving device. For this reason, depending on the power receiving device, the threshold efficiency may become excessively high or low with respect to the maximum transmission efficiency.

  On the other hand, according to the present invention, the threshold efficiency corresponding to the maximum transmission efficiency determined in relation to the power receiving device can be obtained by changing the threshold efficiency based on the information about the power receiving device. Thereby, even if the specifications of the power receiving device are different, it can be suitably determined whether or not to continue power transmission.

  According to a fourth aspect of the present invention, the input unit is configured to be able to input information related to the power receiving device and information related to the received power measured by the power receiving device. And calculating means for calculating the transmission efficiency based on the transmitted power. According to this invention, the transmission efficiency and the threshold efficiency can be compared by calculating the transmission efficiency based on the received power and the transmitted power input to the input unit. Moreover, since it is possible to change the threshold efficiency, calculate the transmission efficiency, and compare both in the power transmission device, it is possible to unify the devices that execute each process. Therefore, simplification of control can be achieved.

  As the “transmission power”, for example, an AC power source includes a rectifier that rectifies and outputs system power to DC power, and a converter that converts DC power rectified by the rectifier into AC power and outputs the AC power. In the configuration, the DC power output from the rectifier or the AC power output from the converter can be considered.

  According to the present invention, even if the specifications of the power transmitting device and the power receiving device are different, it is possible to suitably perform power transmission.

The block diagram which shows the electrical constitution of the non-contact electric power transmission apparatus of 1st Embodiment using the power transmission apparatus and power receiving apparatus which concern on this invention. The flowchart which shows the charge start process performed with a vehicle side controller. The block diagram which shows the electrical constitution of the non-contact electric power transmission apparatus of 2nd Embodiment.

(First embodiment)
A non-contact power transmission device (non-contact power transmission system) including a power transmission device and a power reception device according to the present invention will be described with reference to FIGS. 1 and 2.

  As shown in FIG. 1, the non-contact power transmission device 10 includes a ground side device 11 (stand) provided on the ground and a vehicle side device 21 mounted on the vehicle. The ground side device 11 corresponds to a power transmission device (primary side device), and the vehicle side device 21 corresponds to a power receiving device (secondary side device).

  The ground side device 11 includes a high frequency power source 12 (AC power source) capable of outputting high frequency power (AC power) having a predetermined frequency. The high frequency power source 12 is configured to be capable of outputting sinusoidal high frequency power using system power. Specifically, the high-frequency power source 12 includes a primary side rectifier 12a that rectifies system power into DC power, and a primary side DC / DC converter 12b that converts the voltage into different magnitudes. Further, the high-frequency power source 12 includes a DC / RF converter 12c that converts the direct-current power converted by the primary side DC / DC converter 12b into a rectangular-wave high-frequency power, and the rectangular-wave high-frequency power converted into a sine wave. And a low-pass filter 12d for shaping into high-frequency power. In the following description, the sinusoidal high-frequency power is simply referred to as high-frequency power.

  The high-frequency power output from the high-frequency power source 12 is transmitted to the vehicle-side device 21 in a non-contact manner and used for charging the vehicle battery 22 provided in the vehicle-side device 21. Specifically, the non-contact power transmission device 10 is provided in the vehicle-side device 21 and the power transmitter 13 provided in the ground-side device 11 as a device that performs power transmission between the ground-side device 11 and the vehicle-side device 21. The power receiver 23 is provided. High frequency power is input to the power transmitter 13 via a primary side matching unit 14 provided in the ground side device 11.

  The power transmitter 13 and the power receiver 23 are configured to be capable of magnetic field resonance. Specifically, the power transmitter 13 includes a resonance circuit including a primary coil 13a and a primary capacitor 13b connected in parallel. The power receiver 23 is composed of a resonance circuit including a secondary coil 23a and a secondary capacitor 23b connected in parallel. Both resonance frequencies are set to be the same.

  According to this configuration, when high-frequency power is input from the high-frequency power source 12 to the power transmitter 13 (primary coil 13a), the power transmitter 13 and the power receiver 23 (secondary coil 23a) magnetically resonate. As a result, the power receiver 23 receives a part of the energy of the power transmitter 13. That is, the power receiver 23 receives high frequency power from the power transmitter 13.

  The vehicle-side device 21 includes a secondary-side rectifier 24 that rectifies high-frequency power received by the power receiver 23 into DC power, and a secondary-side DC / DC provided between the secondary-side rectifier 24 and the vehicle battery 22. And a DC converter 25. The secondary side DC / DC converter 25 converts the voltage into a predetermined voltage and outputs it to the vehicle battery 22.

  The primary-side matching unit 14 provided between the high-frequency power source 12 and the power transmitter 13 generates an output impedance of the high-frequency power source 12 and an input impedance of the power transmitter 13 (impedance from the power transmitter 13 to the vehicle battery 22). Align. In addition, a secondary matching unit 26 is provided between the power receiver 23 and the secondary rectifier 24 in the vehicle-side device 21. The secondary side matching device 26 matches the output impedance of the power receiver 23 and the input impedance of the secondary side rectifier 24 (impedance from the secondary side rectifier 24 to the vehicle battery 22). That is, the matching units 14 and 26 are provided on both sides of the coupler including the power transmitter 13 and the power receiver 23, and the reflected wave power generated by the impedance mismatch is reduced by the matching units 14 and 26.

  The ground side device 11 is provided with a power source side controller 15 as control means for controlling the high frequency power source 12. The power supply side controller 15 performs on / off control of the DC power output from the primary side DC / DC converter 12b and performs conversion ratio (transformation ratio) control of the primary side DC / DC converter 12b. Thereby, the power supply side controller 15 can perform on / off control of the high frequency power output from the high frequency power source 12 and control of the magnitude of the high frequency power. Further, the vehicle-side device 21 is provided with a vehicle-side controller 27 configured to be able to detect the storage state of the vehicle battery 22.

  Here, each controller 15 and 27 is configured to be able to exchange information. Specifically, the ground side device 11 is provided with a power source side communication unit 16 electrically connected to the power source side controller 15, and the vehicle side device 21 is electrically connected to the vehicle side controller 27. A vehicle-side communication unit 28 is provided. Each communication unit 16 and 28 is capable of wireless communication. Thereby, the information transmitted from the power supply side controller 15 is transmitted to the vehicle side controller 27 via the communication units 16 and 28, and the information transmitted from the vehicle side controller 27 is supplied to the power source via the communication units 16 and 28. Is transmitted to the side controller 15. The power supply side communication unit 16 corresponds to the input unit of the power transmission device, and the vehicle side communication unit 28 corresponds to the input unit of the power reception device.

The non-contact power transmission device 10 has a configuration for calculating transmission efficiency. The configuration will be described in detail below.
The ground-side device 11 is provided with a transmission power measurement unit 17 that measures transmission power related to the high-frequency power source 12. The transmission power measuring unit 17 is connected between the primary side rectifier 12a of the high frequency power source 12 and the primary side DC / DC converter 12b, and measures DC power rectified by the primary side rectifier 12a. Specifically, the transmission power measuring unit 17 measures the DC voltage output from the primary side rectifier 12a and the DC current flowing between the primary side rectifier 12a and the primary side DC / DC converter 12b. The direct current is a current that flows through the load when the load from the primary side DC / DC converter 12b to the vehicle battery 22 is one load. That is, the transmission power measuring unit 17 measures the DC power input to the load from the primary side DC / DC converter 12 b to the vehicle battery 22.

  The transmission power measuring unit 17 transmits information for specifying the measured transmission power to the power supply controller 15 in response to a request from the power supply controller 15. Thereby, the power supply side controller 15 can grasp | ascertain transmission power.

  The vehicle-side device 21 is provided with a received power measuring unit 29 that measures the received power from the ground-side device 11. The received power measuring unit 29 is connected between the secondary side DC / DC converter 25 and the vehicle battery 22 and measures DC power (DC voltage and DC current) input to the vehicle battery 22. The received power measurement unit 29 transmits the measured received power to the vehicle controller 27 in response to a request from the vehicle controller 27. Thereby, the vehicle side controller 27 can grasp | ascertain the received electric power input into the battery 22 for vehicles.

  The non-contact power transmission apparatus 10 calculates transmission efficiency based on the measurement results of the measurement units 17 and 29, and continues power transmission based on the calculation result (whether the vehicle battery 22 is charged). Determine whether. Specifically, when the vehicle-side controller 27 is disposed at a position where the vehicle can be charged, specifically, when the vehicle is disposed at a position where the power transmitter 13 and the power receiver 23 can magnetically resonate, A charge start process is performed to calculate the transmission efficiency and determine the transition to the charge sequence. The charging start process will be described with reference to FIG.

  First, in step S <b> 101, ground side information that is information related to the ground side device 11 is requested to the power supply side controller 15. And it waits until it receives ground side information in step S102. The power supply side controller 15 transmits ground side information in response to a request from the vehicle side controller 27. The ground side information includes identification information for specifying the specification (version) of the ground side device 11.

  When the ground side information is received, specifically, when the ground side information is input to the vehicle side communication unit 28, the process proceeds to step S103, and threshold efficiency that is a determination criterion for transition to the charging sequence is calculated. Specifically, as shown in FIG. 1, the storage unit 27a provided in the vehicle-side controller 27 stores threshold efficiency calculation data 27aa in which identification information and threshold efficiency are set in association with each other. . The threshold efficiency calculation data 27aa is map data for uniquely deriving the threshold efficiency from the identification information of the ground side device 11. In step S103, the threshold efficiency calculation data 27aa is referred to, and the threshold efficiency corresponding to the received identification information of the ground side device 11 is calculated (derived).

  The threshold efficiency set in the threshold efficiency calculation data 27aa is set according to the specification of the ground side device 11 (and the specification of the vehicle side device 21). Here, the ground side device 11 may have a different shape of the primary side coil 13a or a load impedance of the high frequency power source 12, for example, depending on its specifications. For this reason, the maximum transmission efficiency may vary depending on the specifications of the ground side device 11. The threshold efficiency set in the threshold efficiency calculation data 27aa is set to a different value according to the specifications of the ground side device 11 in consideration of the variation in the maximum transmission efficiency.

  Incidentally, the threshold efficiency calculation data 27aa is configured to be updatable. Specifically, the vehicle-side controller 27 is connected to an external server via the vehicle-side communication unit 28, and acquires update information of the threshold efficiency calculation data 27aa from the external server. Thereby, it is possible to cope with version upgrade of the ground side device 11 or newly developed ground side device 11.

Note that the threshold efficiency set in the threshold efficiency calculation data 27aa may be derived in advance by experiment or may be derived by simulation.
Returning to the description of the charging start process (FIG. 2), after calculating the threshold efficiency, the process proceeds to step S 104, and a request signal for chargeability determination power is transmitted to the power supply side controller 15. And it waits until it receives the transmission power information for specifying transmission power in step S105.

  When receiving the request signal, the power supply controller 15 controls the high frequency power supply 12 (primary DC / DC converter 12b) such that the chargeability determination power is output from the high frequency power supply 12. Furthermore, the power supply side controller 15 requests | requires a measurement result with respect to the transmission power measurement part 17, and grasps | ascertains the transmission power (transmission power information) at the time of outputting the electric power for chargeability determination. Then, the power supply side controller 15 transmits the transmission power information to the vehicle side controller 27.

  By the way, the chargeability determination power is uniquely derived from the identification information of the ground side device 11. The chargeability determination power is set in accordance with the specifications of the ground side device 11 and the vehicle side device 21, and in detail, each device 11, 21 so that DC power is input to the vehicle battery 22. Is set in correspondence with the impedance of each electrical component (vehicle battery 22 or the like) provided in the vehicle. More specifically, the vehicle battery 22 is configured such that the DC power is input to the vehicle battery 22 even when the relative position between the power transmitter 13 and the power receiver 23 fluctuates. Is set to be larger than the minimum power for inputting DC power to the battery (determining whether charging is possible). However, the chargeability determination power is set within a range in which an excessive burden is not applied to the high-frequency power supply 12.

  Incidentally, the relative positions of the power transmitter 13 (primary coil 13a) and the power receiver 23 (secondary coil 23a) are not only the distance between the power transmitter 13 and the power receiver 23, but also the axes of the coils 13a and 23a. The direction, the superposition mode of the coils 13a and 23a, and the like are included. For example, in a configuration in which the power transmitter 13 and the power receiver 23 are arranged in the vertical direction, a position shift of the coils 13a and 23a when viewed from above is considered as an aspect of superimposing the coils 13a and 23a. .

  In addition, about the setting of the electric power for chargeability determination, it is good not only as a structure determined based on the specification of each apparatus 11 and 21, but as a structure determined only based on the specification of the ground side apparatus 11. FIG. However, setting with the relationship with the impedance of each electrical component of the vehicle-side device 21 such as the vehicle battery 22 can grasp the minimum power for determining whether charging is possible with high accuracy, and has a function for determining whether charging is possible. In view of the fact that the margin for securing can be reduced, it is preferable to determine based on the specifications of the devices 11 and 21.

  If the vehicle-side controller 27 receives the transmission power information, the vehicle-side controller 27 proceeds to step S106. In step S106, a measurement result is requested | required with respect to the received power measuring part 29, and received power is grasped | ascertained. Then, it progresses to step S107 and calculates the transmission efficiency which is a ratio of the received power with respect to transmitted power.

  In subsequent step S108, it is determined whether or not the transmission efficiency calculated in step S107 is equal to or higher than the threshold efficiency calculated in step S103. In this case, it can be said that the process of step S103 is a process of changing the threshold efficiency, which is a reference for the determination, based on the ground side information.

  If the calculated transmission efficiency is equal to or higher than the threshold efficiency, it means that there is no problem in power transmission. In this case, in step S109, a transition process to the charging sequence is executed, and this process ends.

  Specifically, for the charging sequence, a request signal for charging power is first transmitted to the power supply side controller 15. The power supply side controller 15 controls the high frequency power supply 12 to switch the power output from the high frequency power supply 12 from the chargeability determination power to the charging power based on the reception of the request signal. The charging power is larger than the chargeability determination power. The output of the charging power is stopped when the charging of the vehicle battery 22 is completed (terminated).

  On the other hand, when the transmission efficiency is lower than the threshold efficiency, it means that there is some trouble in power transmission. In this case, an error sequence transition process is executed in step S110, and this process is terminated. Specifically, the vehicle-side controller 27 transmits a stop request signal for chargeability determination power to the power supply-side controller 15. The power supply side controller 15 controls the high frequency power supply 12 to stop the chargeability determination power when the stop request signal is received.

  For example, when the relative position between the power transmitter 13 and the power receiver 23 is not suitable for magnetic resonance, or when there is a metal object between the power transmitter 13 and the power receiver 23, A case where an abnormality has occurred in either of the devices 11 and 21 can be considered.

Next, the operation of the contactless power transmission device 10 will be described.
The transmission power and the received power are measured in a situation where the chargeability determination power is output, and the transmission efficiency is calculated based on these. Then, when the calculated transmission efficiency is larger than the threshold efficiency, power transmission is continued. Specifically, charging power larger than the chargeability determination power is output, and the vehicle battery 22 is fully charged.

  On the other hand, when the calculated transmission efficiency is lower than the threshold efficiency, power transmission stops. Specifically, the output of chargeability determination power is stopped. Thereby, it is avoided that electric power transmission is performed in a mode in which the transmission efficiency is lower than the threshold efficiency.

  In such a configuration, the threshold efficiency, which is a criterion for determining whether or not to continue power transmission as described above, is changed based on the ground side information. Thereby, the threshold efficiency according to the specification of each apparatus 11 and 21 will be set, and it can be determined suitably whether electric power transmission is continued.

  Specifically, as already described, the maximum transmission efficiency varies depending on the specifications of the devices 11 and 21. For this reason, depending on the specifications of the devices 11 and 21, the maximum transmission efficiency may be low. In this case, the threshold efficiency may be excessively high with respect to the maximum transmission efficiency, and it may be erroneously determined that there is a problem in power transmission despite the situation where normal power transmission can be performed.

  On the other hand, the threshold efficiency of the criterion for determining whether or not to continue power transmission (whether or not there is an obstacle to power transmission) is changed according to the specification (identification information) of the ground side device 11. The threshold efficiency is a value corresponding to the maximum transmission efficiency. For this reason, the situation where the threshold efficiency becomes excessively high with respect to the maximum transmission efficiency as described above is avoided. Therefore, the erroneous determination is unlikely to occur.

  Incidentally, as the specifications of the devices 11 and 21 that affect the transmission efficiency, for example, the resonance frequency of the power transmitter 13 and the power receiver 23, the frequency of the high-frequency power output from the high-frequency power source 12, the shape of each coil 13a, 23a, The storage capacity (impedance) of the vehicle battery 22, the impedance of the matching units 14 and 26, and the like can be considered.

According to the embodiment described in detail above, the following excellent effects are obtained.
(1) In the vehicle-side device 21 of the non-contact power transmission apparatus 10 that continues power transmission when the transmission efficiency is equal to or higher than the threshold efficiency and stops power transmission when the transmission efficiency is smaller than the threshold efficiency, The threshold efficiency is changed based on the ground side information (identification information of the ground side device 11). Thereby, it is possible to avoid a situation in which the power transmission is not erroneously continued due to the fluctuation of the maximum transmission efficiency according to the specification of the ground side device 11. Specifically, the threshold efficiency becomes excessively high with respect to the maximum transmission efficiency, and it is possible to avoid erroneous determination in the power transmission continuation determination. Therefore, even if the specifications of the ground side device 11 (power transmission device) are different, it is possible to suitably perform power transmission.

  (2) The configuration is such that DC power is measured as transmission power and reception power necessary to calculate transmission efficiency. Thereby, compared with the structure which measures high frequency electric power, the measurement of transmitted power and received electric power can be performed comparatively easily. Therefore, the configuration of the transmitted power measuring unit 17 and the received power measuring unit 29 can be simplified. Further, the transmission efficiency can be easily calculated as compared with the configuration in which the transmission efficiency is calculated using the high-frequency power as much as the active power does not need to be calculated.

  (3) The storage unit 27a of the vehicle-side controller 27 stores threshold efficiency calculation data 27aa that is set in association with the identification information of the ground side device 11 and the threshold efficiency, and refers to the threshold efficiency calculation data 27aa. Thus, the threshold efficiency is calculated (derived). As a result, the information amount of the ground side information required for calculating the threshold efficiency can be reduced, and the processing load related to the calculation of the threshold efficiency can be reduced. Therefore, it is possible to reduce the processing load related to the change in threshold efficiency.

  In general, it is assumed that the ground-side device 11 provided on the ground has a lower update frequency than the vehicle-side device 21 mounted on the vehicle. For this reason, the update frequency of the threshold efficiency calculation data 27aa accompanying the update of the ground device 11 and the addition of new identification information can be reduced. Therefore, in the configuration in which the vehicle-side controller 27 calculates the threshold efficiency of the change destination using the identification information of the ground-side device 11 and the threshold efficiency calculation data 27aa, maintenance can be facilitated.

  (4) The transmission efficiency is calculated based on the transmitted power and the received power in a state where the chargeability determination power smaller than the charging power is output, and the calculated transmission efficiency is compared with the threshold efficiency. As a result, it is possible to suppress an increase in power loss and an increase in burden on the high-frequency power source 12 due to the generation of excessive reflected wave power at the stage of calculating the transmission efficiency. In particular, when the specifications of the devices 11 and 21 are greatly different, the reflected wave power based on impedance mismatch tends to increase. On the other hand, by adopting a configuration for outputting the chargeability determination power, even if the specifications of the devices 11 and 21 are greatly different, the reflected wave power can be reduced, and the various increases described above can be achieved. Can be suppressed.

  (5) The vehicle-side communication unit 28 can receive the measurement result of the transmitted power measurement unit 17, and the vehicle-side controller 27 transmits the transmission efficiency based on the measurement result and the measurement result of the received power measurement unit 29. It was set as the structure which calculates. As a result, processing related to calculation (change) of threshold efficiency, calculation of transmission efficiency, and determination of transition to a charging sequence (comparison between transmission efficiency and threshold efficiency) is centralized in the vehicle-side controller 27. Therefore, simplification of control can be achieved.

  In particular, for example, a configuration in which the vehicle-side controller 27 transmits the measurement result of the received power measuring unit 29 to the power-side controller 15 and the power-side controller 15 calculates transmission efficiency is also conceivable. However, in this configuration, it is necessary to transmit the calculated transmission efficiency to the vehicle-side controller 27. For this reason, the frequency with which information is exchanged between the power supply side controller 15 and the vehicle side controller 27 is increased, the control becomes complicated, and there is a concern that the processing time may be prolonged.

  On the other hand, according to the present embodiment, the control unit that executes each of the above processes is centralized in one controller (vehicle-side controller 27), and therefore the frequency of information exchange between the controllers 15 and 27. Is less. Thereby, simplification of control and shortening of processing time can be achieved.

(Second Embodiment)
In the present embodiment, the configuration related to the calculation of transmission efficiency is different from that in the first embodiment. The different points will be described with reference to FIG. In addition, about the structure same as 1st Embodiment, while attaching | subjecting the same code | symbol, the description is abbreviate | omitted.

  As shown in FIG. 3, the ground-side device 111 of the non-contact power transmission apparatus 100 of the present embodiment is provided with a transmission power measurement unit 112 that measures high-frequency power output from the high-frequency power source 12. In addition, the vehicle-side device 121 of the contactless power transmission apparatus 100 according to the present embodiment is provided with a received power measuring unit 122 that measures high-frequency power output from the secondary matching unit 26 (power receiver 23). . The vehicle-side controller 27 calculates the transmission efficiency based on the active power of these high frequency powers.

  Further, the vehicle-side device 121 is provided with a fixed load 123 having a predetermined fixed impedance. The vehicle-side device 121 is provided with a relay 124 that can switch the connection destination of the secondary matching unit 26 between the fixed load 123 and the secondary rectifier 24.

  Here, the vehicle-side controller 27 controls the relay 124 in the charging start process. Specifically, the vehicle-side controller 27 determines that the connection destination of the secondary matching unit 26 is the fixed load 123 at a stage prior to the output request processing for the chargeability determination power (step S104 (see FIG. 2)). The relay 124 is controlled so that The vehicle-side controller 27 then relays the connection destination of the secondary-side matching unit 26 from the fixed load 123 to the secondary-side rectifier 24 in the transition process to the charging sequence (step S109 (see FIG. 2)). 124 is controlled.

  The operation of the present embodiment will be described. Since the connection destination of the secondary matching unit 26 is the fixed load 123 before the chargeability determination power is output, it is used to calculate the transmission efficiency. The transmitted power and the received power are values when connected to the fixed load 123.

  Here, the impedance of the vehicle battery 22 varies according to the input electric power (electric energy). For this reason, when the load from the secondary side rectifier 24 to the vehicle battery 22 is one load, the load is a variable load whose impedance varies. Then, when the transmission power and the reception power when connected to the variable load are measured and the transmission efficiency is calculated based on the measurement result, the calculated transmission efficiency is affected by the variable load. As a result, the accuracy of the determination of transition to the charging sequence is reduced.

  On the other hand, according to the present embodiment, as described above, the transmission efficiency is calculated based on the transmitted power and the received power measured in the state of being connected to the fixed load 123, so that the transition to the charging sequence is performed. In the determination, the influence of the vehicle battery 22 is excluded.

According to this embodiment explained in full detail above, in addition to the effect of said (1)-(5), there exist the following effects.
(6) A fixed load 123 is provided in the vehicle-side device 121, and the connection destination of the secondary matching unit 26 (power receiver 23) is connected to the fixed load 123, the secondary rectifier 24, and the secondary DC / DC. A relay 124 for switching to a variable load including the converter 25 and the vehicle battery 22 is provided. And it was set as the structure which calculates transmission efficiency based on the transmitted power and received power measured in the condition connected to the fixed load 123. FIG. Thereby, the influence of the fluctuation | variation of the impedance of the battery 22 for vehicles does not reach the calculated transmission efficiency. Therefore, the change in impedance of the vehicle battery 22 does not contribute to the determination of transition of the charging sequence. Therefore, it is possible to improve the accuracy of determination of transition of the charging sequence.

In addition, you may change the said embodiment as follows.
In each embodiment, the vehicle-side controller 27 performs the calculation of the threshold efficiency and the transmission efficiency and the determination of the transition to the charging sequence. However, the present invention is not limited to this, and the power-source controller 15 performs these processes. It may be configured to execute. In this case, the vehicle-side controller 27 transmits information on the vehicle-side devices 21 and 121 and vehicle-side information including the identification information of the vehicle-side devices 21 and 121 to the power supply-side controller 15. Then, threshold efficiency calculation data in which the identification information of the vehicle side devices 21 and 121 and the threshold efficiency are associated with each other is provided in the storage unit of the power supply side controller 15. The power supply side controller 15 calculates the threshold efficiency by referring to the threshold efficiency calculation data, and determines the transition to the charging sequence based on the comparison result between the transmission efficiency and the threshold efficiency. Thereby, there exists an effect demonstrated in each said embodiment.

  That is, the configuration for calculating the threshold efficiency and determining the shift to the charging sequence based on the calculation result may be provided in any of the ground side devices 11 and 111 and the vehicle side devices 21 and 121.

  In each embodiment, the threshold efficiency is calculated based on the identification information of the ground side devices 11 and 111, but is not limited thereto. For example, the vehicle-side controller 27 (the vehicle-side communication unit 28), as ground side information, information on the primary side coil 13a (for example, shape information of the primary side coil 13a), resonance frequency information of the power transmitter 13, and a high frequency power source It is good also as a structure which receives the frequency information of the high frequency electric power from 12. In this case, the vehicle-side controller 27, the information on the ground side, information on the secondary coil 23a, resonance frequency information of the power receiver 23, and information on the vehicle battery 22 (for example, maximum storage capacity information of the vehicle battery 22). ) And the threshold efficiency may be calculated based on the above. Specifically, a relational expression capable of calculating the threshold efficiency from each information is stored in the storage unit 27a, and the vehicle-side controller 27 calculates the transmission efficiency using the relational expression. According to this configuration, the threshold efficiency can be calculated without using the identification information of the ground side devices 11 and 111 and the threshold efficiency calculation data 27aa. Thereby, since it is not necessary to update the threshold efficiency calculation data 27aa, the maintenance can be facilitated. However, in view of the complexity of the control related to the calculation of the threshold efficiency, the configuration using the identification information of the ground side devices 11 and 111 and the threshold efficiency calculation data 27aa is preferable.

  In addition, when the power supply side controller 15 calculates threshold efficiency, the power supply side controller 15 (power supply side communication part 16), as vehicle side information, the information regarding the secondary side coil 23a, the resonance frequency information of the power receiver 23, And it is good to comprise so that the information regarding the battery 22 for vehicles can be received.

  Incidentally, in view of the fact that the vehicle-side devices 21 and 121 tend to have a higher update frequency, in the configuration in which the power-source controller 15 calculates the threshold efficiency, it is preferable to calculate using the above relational expression. . As a result, it is possible to suppress complication of maintenance due to an increase in the update frequency of the threshold efficiency calculation data.

  In each embodiment, the threshold efficiency is determined based on the specifications of the devices 11 and 21 (or the devices 111 and 121), but is not limited thereto, and in addition to the above specifications, the power transmitter 13 Further, various sensors (for example, a distance sensor) that grasp the relative position of the power receiver 23 may be provided, and the threshold efficiency may be changed according to the relative position. However, if attention is paid to simplification of control related to the change in threshold efficiency, a configuration that does not consider the relative position is preferable.

  In each embodiment, the controllers 15 and 27 are configured to acquire the ground side information by exchanging information through wireless communication. However, the present invention is not limited to this. For example, the vehicle-side devices 21 and 121 may be separately provided with an input terminal through which the user can input ground-side information, and the ground-side information is input to the input terminal, thereby acquiring the ground-side information. Good. In this case, the vehicle side communication unit 28 that receives the input terminal and the transmitted power corresponds to the input unit.

  In addition to the ground side devices 11 and 111 and the vehicle side devices 21 and 121, a control device that has an input terminal that can input ground side information and can exchange information with the vehicle side devices 21 and 121 is provided. The control device may be configured to transmit the ground-side information input to the input terminal to the vehicle-side devices 21 and 121. The same applies to the case where the power supply side controller 15 calculates the threshold efficiency.

  In each embodiment, when the calculated transmission efficiency is lower than the threshold efficiency, the power transmission is immediately stopped. However, the present invention is not limited to this. For example, whether or not charging is possible over a predetermined specific period. It is good also as a structure which continues the output of the electric power for determination. In this case, using a notification device (for example, a display unit of a navigation device) mounted on the vehicle, notification that prompts alignment of the power transmitter 13 and the power receiver 23 is performed. And the process of step S104-step S108 is repeatedly performed with a predetermined period until the specific period passes. Then, when the transmission efficiency is equal to or higher than the threshold efficiency within the specific period, the process proceeds to the charging sequence, and when the transmission efficiency is not equal to or higher than the threshold efficiency within the specific period, the process proceeds to the error sequence, It is good also as a structure which stops electric power transmission.

  In other words, “the power transmission is stopped when the transmission efficiency is lower than the threshold efficiency” means that the power transmission is stopped immediately after the comparison between the transmission efficiency and the threshold efficiency is made, A configuration is included in which power transmission is stopped when a specific period has elapsed since the determination was first made. The specific period is, for example, a period during which alignment of the coils 13a and 23a can be performed, or a period during which foreign matter can be confirmed.

  ○ If the calculated transmission efficiency is lower than the threshold efficiency, power transmission (output of chargeability determination power) is temporarily stopped, position adjustment is performed, and then power transmission is performed again. Good. That is, the configuration of “stopping power transmission” includes a mode of temporarily stopping (interrupting).

  In each embodiment, the process of steps S104 to S108 is executed at the start of charging. However, the above processes may be executed periodically during charging. In this case, since power transmission stops when an abnormality occurs during charging, it is possible to appropriately cope with the abnormality during charging.

  In the second embodiment, a separate rectifier may be provided between the relay 124 and the fixed load 123. In this case, the received power measuring unit 122 may be configured to measure the DC power output from the rectifier. Thereby, in the configuration connected to the fixed load 123 at the time of calculating the transmission efficiency, it is possible to use DC power as received power.

Further, for example, a relay 124 may be provided between the secondary side rectifier 24 and the secondary side DC / DC converter 25. Even in this case, the above effects can be achieved.
In each embodiment, the calculation of threshold efficiency, the calculation of transmission efficiency, and the comparison between the two are performed by the same controller (vehicle-side controller 27). It is good also as a structure shared by each controller 15 and 27. FIG. For example, the threshold efficiency may be calculated by the vehicle controller 27 and the transmission efficiency may be calculated by the power controller 15.

In each embodiment, the threshold efficiency calculation data 27aa is configured to be updatable. However, the present invention is not limited to this and may be configured not to be updated.
The impedance of each matching unit 14, 26 may be set to a fixed value or may be variable. When making it variable, it is preferable that the power transmitter 13 and the power receiver 23 be configured to follow changes in relative positions. Thereby, even if the relative position varies, a high degree of alignment can be maintained. Further, since the matching devices 14 and 26 absorb fluctuations in the input impedance and output impedance of the coupler, it is not necessary to consider the fluctuations in the high-frequency power source 12 and the secondary rectifier 24 to the vehicle battery 22. . Thereby, control can be facilitated.

  Incidentally, in the configuration in which the impedances of the matching units 14 and 26 are varied, the impedances of the matching units 14 and 26 are first varied so that the transmission efficiency is maximized. The transmission efficiency in that state is compared with the threshold efficiency. That is, in the configuration in which the impedances of the matching units 14 and 26 are varied, the transmission efficiency is after the variable control of the impedances of the matching units 14 and 26 is performed so that the transmission efficiency is maximized.

The matching units 14 and 26 may be omitted.
In the first embodiment, the DC power output from the primary rectifier 12a of the high-frequency power source 12 is adopted as the transmission power, but not limited to this, the transmission power is output from the primary DC / DC converter 12b. DC power may be employed.

  Moreover, although the direct-current power input into the vehicle battery 22 was employ | adopted as received power, it is not restricted to this, You may employ | adopt the direct-current power output from the secondary side rectifier 24. FIG. However, in view of the point that transmission efficiency including power loss of the primary side DC / DC converter 12b and the like can be calculated, the configuration of the first embodiment is preferable.

  ○ Furthermore, in the first embodiment, the transmission efficiency is calculated by adopting DC power for both transmitted power and received power, and in the second embodiment, high frequency power (AC power) is employed for both transmitted power and received power. Thus, the transmission efficiency is calculated, but the present invention is not limited to this. One of the transmitted power and the received power may be DC power, and the other may be high frequency power. In this case, the transmission efficiency is calculated from the effective power of the high frequency power and the DC power.

In each embodiment, the primary side DC / DC converter 12b and the secondary side DC / DC converter 25 are provided, but the present invention is not limited to this and may be omitted.
A primary side induction coil that is coupled to the resonance circuit including the primary side coil 13a and the primary side capacitor 13b by electromagnetic induction may be separately provided in the power transmitter 13. In this case, the primary side induction coil and the high frequency power source 12 are connected, and the resonance circuit is configured to receive high frequency power from the primary side induction coil by electromagnetic induction. Similarly, the power receiver 23 is provided with a secondary side induction coil that is coupled by electromagnetic induction to a resonance circuit composed of the secondary side coil 23a and the secondary side capacitor 23b, and the resonance of the power receiver 23 using the secondary side induction coil. Power may be extracted from the circuit.

The waveform of the high frequency power output from the high frequency power supply 12 is not limited to a sine wave, and may be a pulse wave, for example.
O Although the high frequency power supply 12 which outputs high frequency electric power was provided, it is not restricted to this. In short, any AC power source that outputs AC power of a predetermined frequency (for example, 10 kHz to 10 MHz) may be used, and the frequency of the output AC power may be appropriately set in relation to the resonance frequency or the like.

In the embodiment, the capacitors 13b and 23b are provided, but these may be omitted. In this case, magnetic field resonance is performed using the parasitic capacitances of the coils 13a and 23a.
In the embodiment, magnetic field resonance is used in order to realize non-contact power transmission. However, the present invention is not limited to this, and electromagnetic induction may be used.

In the embodiment, the vehicle-side devices 21 and 121 as the power receiving devices are mounted on the vehicle, but the configuration is not limited to this, and may be mounted on other devices such as a mobile phone.
In the embodiment, the high-frequency power received by the power receiver 23 is used to charge the vehicle battery 22, but is not limited to this. For example, other electronic devices provided in the vehicle are driven. It may be used for

  Next, the technical idea that can be grasped from the above embodiment and other examples will be described below. For easy understanding, the corresponding configuration in each embodiment is appropriately shown in parentheses for some configurations, but is not limited to this.

(A) a variable load whose impedance varies depending on the situation;
A fixed load having a fixed value with a predetermined impedance;
Switching means (relay 124) capable of switching the connection destination of the secondary coil between the variable load and the fixed load;
With
The said calculation means calculates the said transmission efficiency based on the said transmitted power and the said received power when the connection destination of the said secondary side coil becomes the said fixed load, The said transmission efficiency is characterized by the above-mentioned. The power receiving device described in 1.

(B) The input unit is configured to be able to input identification information of the power transmission device as information about the power transmission device,
The changing unit includes an information group (threshold efficiency calculation data 27aa) in which identification information of the power transmission device and the threshold efficiency are associated with each other, and the power transmission device input to the input unit based on the information group. The power receiving device according to any one of claims 1 and 2 and the technical concept (a), wherein threshold efficiency corresponding to the identification information is derived and changed to the threshold efficiency.

(C) The input unit is configured to be able to input information about the primary coil and frequency information of the AC power as information about the power transmission device,
The changing means derives threshold efficiencies corresponding to the respective information based on information on the primary coil input to the input unit and frequency information of the AC power, and changes the threshold efficiencies. The power receiving device according to any one of claims 1 and 2, and the technical idea (a).

(D) comprising control means for controlling the AC power supply so that the AC power for calculation is output as the AC power;
The calculation means calculates the transmission efficiency based on the transmitted power and the received power at the time of output of the calculation AC power,
The control means controls the AC power supply so that an AC power larger than the AC power for calculation is output when the transmission efficiency calculated by the calculation means is higher than the threshold efficiency. The power transmission device according to claim 4.

(E) The input unit is configured to be able to input identification information of the power receiving device as information about the power receiving device.
The change unit includes an information group in which identification information of the power receiving device and the threshold efficiency are associated with each other, and threshold efficiency corresponding to the identification information of the power receiving device input to the input unit based on the information group The power transmission device according to any one of claims 3 and 4 and the technical idea (d), wherein the threshold efficiency is derived.

(F) The input unit is configured to be able to input information about the secondary coil and information about a load provided in the power receiving device as information about the power receiving device,
The changing means derives a threshold efficiency corresponding to each piece of information based on information on the secondary coil and information on the load input to the input unit, and changes the threshold efficiency to the threshold efficiency. The power transmission device according to any one of claims 3 and 4 and the technical idea (d).

(G) an AC power source that outputs AC power, and a power transmission device having a primary coil to which the AC power is input;
A power receiving device having a secondary side coil capable of receiving the AC power in a non-contact manner from the primary side coil;
In a non-contact power transmission device that continues power transmission when the transmission efficiency is higher than a predetermined threshold efficiency, and stops power transmission when the transmission efficiency is lower than the threshold efficiency,
A non-contact power transmission apparatus, comprising: a changing unit that is provided in any one of the power transmission device and the power receiving device and changes the threshold efficiency based on information on the other device.

  (H) The non-contact power according to the technical concept (g), wherein the changing means changes the threshold efficiency based on identification information of the other device as information on the other device. Transmission equipment.

(I) The primary coil constitutes a primary resonance circuit,
The secondary coil constitutes a secondary resonance circuit,
The changing means has a threshold based on the frequency of the AC power output from the AC power supply, the resonance frequency of the primary side resonance circuit and the secondary side resonance circuit, and a load provided in the power receiving device. The non-contact power transmission apparatus according to the technical concept (g), wherein the efficiency is derived and changed to the threshold efficiency.

  DESCRIPTION OF SYMBOLS 10 ... Non-contact electric power transmission apparatus of 1st Embodiment, 11 ... Ground side apparatus as power transmission apparatus, 12 ... High frequency power supply, 13 ... Power transmitter, 13a ... Primary side coil, 15 ... Power supply side controller, 16 ... Power supply side Communication unit, 17 ... transmitted power measurement unit, 21 ... vehicle side device as power receiving device, 22 ... vehicle battery, 23 ... power receiver, 23a ... secondary coil, 27 ... vehicle side controller as change means and calculation means , 28 ... Vehicle side communication unit, 100 ... Non-contact power transmission device of the second embodiment, 111 ... Ground side equipment, 121 ... Vehicle side equipment, 123 ... Fixed load, 124 ... Relay.

Claims (4)

When the transmission efficiency is higher than a predetermined threshold efficiency, the power transmission between the power transmitting device and the power receiving device is continued, and when the transmission efficiency is lower than the threshold efficiency, the power transmission is stopped. A power receiving device for a power transmission device,
A secondary coil capable of receiving AC power from a primary coil provided in the power transmission device;
An input unit capable of inputting information on the power transmission device;
Changing means for changing the threshold efficiency based on information on the power transmission equipment input to the input unit;
A power receiving device comprising: The input unit is configured to be able to input information on the power transmission device and information on transmission power measured by the power transmission device,
The power receiving device according to claim 1, further comprising a calculating unit that calculates the transmission efficiency based on the transmitted power and the received power measured by itself. When the transmission efficiency is higher than a predetermined threshold efficiency, the power transmission between the power transmitting device and the power receiving device is continued, and when the transmission efficiency is lower than the threshold efficiency, the power transmission is stopped. A power transmission device of a power transmission device,
An AC power supply that outputs AC power;
A primary coil capable of transmitting the AC power in a non-contact manner to a secondary coil provided in the power receiving device;
An input unit capable of inputting information on the power receiving device;
Changing means for changing the threshold efficiency based on information on the power receiving device input to the input unit;
A power transmission device comprising: The input unit is configured to be able to input information related to the power receiving device and information related to received power measured by the power receiving device.
The power transmission device according to claim 3, further comprising a calculation unit that calculates the transmission efficiency based on the received power and transmission power measured by itself.