WO2015159962A1

WO2015159962A1 - Contactless power-transfer apparatus and power-transmitting device

Info

Publication number: WO2015159962A1
Application number: PCT/JP2015/061764
Authority: WO
Inventors: 琢磨小野; 竜也安久
Original assignee: 株式会社豊田自動織機
Priority date: 2014-04-18
Filing date: 2015-04-16
Publication date: 2015-10-22
Also published as: JP2015208100A

Abstract

This contactless power-transfer apparatus contains the following: a power-transmitting device that has a primary-side coil; a power-receiving device that has a secondary-side coil and a second AC power supply; a power-reception detection unit; a presence determination unit; and a transfer determination unit. When AC power is inputted from the second AC power supply to the secondary-side coil upon the presence determination unit determining that a target object is present near the primary-side coil, the transfer determination unit determines, on the basis of the result of detection performed by the power-reception detection unit, whether or not power is being transferred from the secondary-side coil to the primary-side coil.

Description

Non-contact power transmission device and power transmission equipment

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

A non-contact power transmission device that does not use a power cord or power transmission cable is known. The non-contact power transmission device is, for example, non-contact from an AC power source that outputs AC power of a predetermined frequency, and a power transmission device having a primary coil to which the AC power is input, from the primary coil. A power receiving device having a secondary coil configured to receive AC power. For example, see Patent Document 1. In such a non-contact power transmission device, AC power is transmitted from a power transmitting device to a power receiving device in a non-contact manner, for example, by magnetic resonance between the primary side coil and the secondary side coil. Patent Document 1 describes that a power receiving device is mounted on a vehicle as an object.

JP 2009-106136 A

Depending on the conditions such as the relative position of the primary side coil and the secondary side coil, power transmission from the primary side coil to the secondary side coil may not be performed sufficiently. For this reason, it may be required to grasp whether or not power transmission is performed between the primary side coil and the secondary side coil.

An object of the present invention is to provide a non-contact power transmission device and a power transmission device that can appropriately grasp whether or not power transmission is performed between a primary side coil and a secondary side coil.

The non-contact power transmission device that achieves the above object includes a first AC power source that outputs AC power, a power transmission device that has a primary coil to which AC power is input from the first AC power source, and the first AC power source. A secondary coil configured to contactlessly receive AC power input from the power source to the primary coil; and a second AC power source that outputs AC power to the secondary coil. A power receiving device, a power receiving detection unit that is provided in the power transmitting device and that detects AC power received by the primary coil in a non-contact manner from the secondary coil, and an object on which the power receiving device is mounted is the first device. A presence determination unit that determines whether or not the secondary coil exists around the secondary coil, and the second AC power source triggered by the presence determination unit determining that the object is present around the primary coil To the secondary side A transmission determination unit that determines whether or not power transmission from the secondary side coil to the primary side coil is performed based on a detection result of the power reception detection unit And.

A power transmission device that achieves the above object includes: a first AC power source that outputs AC power; and a primary coil that receives AC power from the first AC power source. A secondary coil and the secondary side It is comprised so that alternating current power may be transmitted non-contactedly with respect to the said secondary side coil of the receiving device which has a 2nd alternating current power supply which outputs alternating current power to a coil. In the power transmission device, a power reception detection unit that detects AC power received by the primary coil from the secondary coil in a contactless manner, and an object on which the power reception device is mounted are present around the primary coil. A presence determination unit that determines whether or not to do so. When the presence determination unit determines that the object is present around the primary coil, the AC detection is performed when AC power is input from the second AC power source to the secondary coil. Based on the detection result of the part, it is determined whether or not power transmission from the secondary coil to the primary coil is performed.

The block diagram which shows the electrical structure of a non-contact electric power transmission apparatus and power transmission equipment. The flowchart which shows a charge preparation process. (A), (b) is a schematic diagram which shows a mode that a vehicle is parked. (A) is a graph which shows the fluctuation | variation of a power factor, (b) is a graph which shows the fluctuation | variation of received electric power. The block diagram which shows the electric constitution of the power transmission apparatus of another example.

Hereinafter, an embodiment of a non-contact power transmission device (non-contact power transmission system) and a power transmission device (power transmission device) will be described.
As shown in FIG. 1, the non-contact power transmission device 10 includes a power transmission device 11 (ground side device, primary side device) and a power receiving device 21 (vehicle side device, secondary side device) capable of non-contact power transmission. It has. The power transmission device 11 is provided on the ground, and the power reception device 21 is mounted on the vehicle 100.

The power transmission device 11 includes an AC power source 12 as a first AC power source capable of outputting AC power having a predetermined frequency. The AC power supply 12 is a voltage source, for example. The AC power supply 12 is configured to be able to convert the grid power to AC power and output the converted AC power when grid power is input as external power from the grid power supply E as an infrastructure.

Specifically, the AC power supply 12 includes an AC / DC converter 12a as a first conversion unit and a DC / AC converter 12b as a second conversion unit. The AC / DC converter 12a converts system power input from the system power supply E into DC power. The DC / AC converter 12b receives DC power from the AC / DC converter 12a, converts the DC power into AC power, and outputs the converted AC power.

The AC / DC converter 12a of the present embodiment is configured such that the power value of the DC power output from the AC / DC converter 12a is variable. Thereby, the AC power supply 12 can output a plurality of types of AC power having different power values. Further, the DC / AC converter 12b of the present embodiment is a unidirectional converter that can convert DC power to AC power but cannot convert AC power to DC power.

AC power output from the AC power supply 12 is transmitted to the power receiving device 21 in a non-contact manner, and used for charging a vehicle battery 22 (power storage device) provided in the power receiving device 21. Specifically, the non-contact power transmission apparatus 10 includes a primary side resonator 13 and a secondary side resonator 23 that perform power transmission between the power transmission device 11 and the power reception device 21. The primary-side resonator 13 is provided in the power transmission device 11 and receives AC power output from the AC power supply 12. The secondary resonator 23 is provided in the power receiving device 21.

The primary side resonator 13 and the secondary side resonator 23 have the same configuration, and both are configured to be capable of magnetic field resonance. Specifically, the primary side resonator 13 has a resonance circuit including a primary side coil 13a and a primary side capacitor 13b connected in parallel to each other. The secondary side resonator 23 has a resonance circuit including a secondary side coil 23a and a secondary side capacitor 23b connected in parallel to each other. The resonant frequencies of both resonant circuits are set to be the same.

According to this configuration, in a situation where the relative position of the primary side resonator 13 and the secondary side resonator 23 is at a position where magnetic field resonance is possible, AC power is supplied to the primary side resonator 13 (primary side coil 13a). When input, the primary side resonator 13 and the secondary side resonator 23 (secondary side coil 23a) perform magnetic field resonance. As a result, the secondary resonator 23 receives a part of the energy from the primary resonator 13. That is, the secondary resonator 23 receives AC power from the primary resonator 13.

By the way, the frequency of the AC power output from the AC power source 12 is such that the primary side resonator 13 and the secondary side resonance can be transmitted between the primary side resonator 13 and the secondary side resonator 23. It is set corresponding to the resonance frequency of the vessel 23. For example, the frequency of the AC power is set to be the same as the resonance frequency of the primary side resonator 13 and the secondary side resonator 23. However, the present invention is not limited to this, and the frequency of the AC power and the resonance frequency of the primary-side resonator 13 and the secondary-side resonator 23 may be deviated as long as power transmission is possible.

The power receiving device 21 includes a power conversion unit 24 capable of bidirectional conversion between AC power and DC power. The power converter 24 is provided between the secondary resonator 23 and the vehicle battery 22. When the AC power received by the secondary resonator 23 is input, the power converter 24 converts the AC power into DC power and outputs the converted DC power to the vehicle battery 22. To do. In this case, the vehicle battery 22 is charged.

When DC power is input from the vehicle battery 22 by discharging the vehicle battery 22, the power conversion unit 24 converts the DC power into AC power, and the converted AC power is converted into the AC power. Output to the secondary-side resonator 23. In this case, if the primary side resonator 13 and the secondary side resonator 23 are arranged at a position where magnetic field resonance is possible, power transmission from the secondary side resonator 23 to the primary side resonator 13 is performed. Is done. The vehicle battery 22 and the power converter 24 correspond to a second AC power source that outputs AC power.

The power receiving device 21 includes a secondary side detection unit 25 that detects AC power received by the secondary side resonator 23. The secondary side detection unit 25 detects the voltage value and current value of the AC power received by the secondary side resonator 23, and transmits the detection result to the vehicle side controller 26 provided in the power receiving device 21. The vehicle controller 26 is also referred to as a secondary controller. The vehicle-side controller 26 performs control of power conversion by the power conversion unit 24 and switching control of charging or discharging of the vehicle battery 22.

The power receiving device 21 includes a SOC sensor (not shown) that detects the state of charge (SOC: State of Charge) of the vehicle battery 22 and transmits the detection result to the vehicle-side controller 26.

The power transmission device 11 includes a power supply side controller 14 that controls the AC / DC converter 12a and the DC / AC converter 12b. The power supply controller 14 is also referred to as a primary controller. The power supply side controller 14 and the vehicle side controller 26 are configured to be capable of wireless communication with each other. The non-contact power transmission apparatus 10 performs control such as start or end of power transmission while the

controllers

14 and 26 exchange information with each other. Note that a specific method of wireless communication between the

controllers

14 and 26 is arbitrary. For example, Zigbee (registered trademark) and Bluetooth (registered trademark) are conceivable.

The power transmission device 11 includes an impedance converter 30 that is provided between the AC power supply 12 (specifically, the DC / AC converter 12b) and the primary-side resonator 13 and performs impedance conversion. The impedance converter 30 is composed of, for example, a transformer or an LC circuit.

Components from the input end of the impedance converter 30 (output end of the DC / AC converter 12b) to the vehicle battery 22 are regarded as one power load. The power factor for the power source load in the case where charging power, which is AC power having a predetermined specific power value, is output from the AC power source 12 and the relative position of each of the

resonators

13 and 23 is a predetermined reference position. The impedance converter 30 converts the input impedance of the primary side resonator 13 (primary side coil 13a) so that λ preferably matches with “1”. That is, the impedance converter 30 of this embodiment is a power factor correction circuit.

As described above, the primary side resonator 13 is used to transmit AC power output from the AC power source 12 to the secondary side resonator 23 in a non-contact manner, and also from the secondary side resonator 23. Used to receive power without contact. Correspondingly, the power transmission device 11 is configured so that the electrical characteristics relating to AC power (hereinafter simply referred to as “transmission power”) output from the AC power source 12 and the primary resonator 13 are contactless from the secondary resonator 23. It is configured to be able to detect electrical characteristics relating to received AC power (hereinafter simply referred to as “received power”).

Specifically, as shown in FIG. 1, the power transmission device 11 is used to detect the output power value and the power factor λ of the AC / DC converter 12 a as a device that detects electrical characteristics related to transmitted power. A power transmission detection unit 31 is provided. The power transmission detection unit 31 detects the output voltage value and the output current value of the AC / DC converter 12a, detects the output current value of the DC / AC converter 12b, and transmits the detection result to the power supply side controller 14. . The power supply side controller 14 calculates the output power value of the AC / DC converter 12a based on the output voltage value and the output current value of the AC / DC converter 12a, and the output current value of the AC / DC converter 12a and the DC The power factor λ is calculated based on the output current value of the / AC converter 12b. The output current value of the DC / AC converter 12b is, for example, an effective value. It can also be said that the power transmission detection unit 31 detects a change in at least one of a voltage value and a current value in the power transmission device 11.

Note that “detecting a change in at least one of a voltage value and a current value in the power transmission device 11” means a voltage value at a predetermined position on the power transmission path from the AC / DC converter 12a to the primary coil 13a. In addition to directly detecting at least one fluctuation of the current value, at least one of the voltage value and the current value by detecting fluctuations of various parameters that vary due to the fluctuation, such as power factor and power value. Including indirectly detecting fluctuations.

The power transmission device 11 is configured to connect a power receiving detection unit 32 that detects received power that is AC power received by the primary side resonator 13 and a connection destination of the primary side resonator 13 (primary side coil 13a) to an AC power source. 12 (specifically, a DC / AC converter 12b) or a switching relay 33 (switching unit) for switching to the power reception detection unit 32. The switching relay 33 is disposed between the DC / AC converter 12 b and the primary side resonator 13, specifically between the impedance converter 30 and the primary side resonator 13. The power reception detection unit 32 detects the received power in a state where the power reception detection unit 32 is connected to the primary resonator 13 by the switching relay 33 and transmits the detection result to the power supply side controller 14.

As shown in FIG. 1, the connection between the primary side resonator 13 and the AC power source 12 by the switching relay 33 is another component (for example, the impedance converter 30) between the primary side resonator 13 and the AC power source 12. ) Is included.

The power supply side controller 14 and the vehicle side controller 26 are charged for confirming that power transmission from the power transmitting device 11 to the power receiving device 21 is normally performed before starting full-scale charging of the vehicle battery 22. Perform preparatory processing. In the charging preparation process, the power supply side controller 14 determines whether or not the vehicle 100 as an object on which the power receiving device 21 is mounted exists around the primary side resonator 13, and the determination result is affirmative determination In this case, a transmission determination is made as to whether or not power transmission is performed between the primary side resonator 13 and the secondary side resonator 23.

Incidentally, the charge preparation process of the present embodiment can be exchanged between the

controllers

14 and 26, for example, and is executed before the vehicle 100 stops, that is, during the movement of the vehicle 100 (parking operation). Is done. For example, the specific execution trigger of the charging preparation process is when the vehicle 100 enters the wireless communication range of the power controller 14.

The charging preparation process will be described with reference to the flowchart of FIG. For the convenience of illustration, FIG. 2 shows a charge preparation process executed by the power supply controller 14 and a charge preparation process executed by the vehicle controller 26. Further, signals exchanged between the

controllers

14 and 26 are indicated by broken lines.

First, the charge preparation process executed by the power supply controller 14 will be described. As shown in FIG. 2, the power supply side controller 14 controls the switching relay 33 so that the primary side resonator 13 and the alternating current power supply 12 (DC / AC converter 12b) are mutually connected in step S101.

Thereafter, in step S102, the power supply controller 14 starts temporary power transmission. Specifically, the power supply side controller 14 controls the AC / DC converter 12 a and the DC / AC converter 12 b so that the temporary power transmission power is output from the AC power supply 12. The power value of the temporary power transmission is smaller than the power value of the charging power.

In subsequent step S 103, the power supply side controller 14 calculates the power factor λ based on the detection result of the power transmission detection unit 31. In step S104, the power supply controller 14 determines whether or not the calculated power factor λ is equal to or greater than a predetermined threshold power factor λth. If the calculated power factor λ is greater than or equal to the threshold power factor λth, the power supply controller 14 proceeds to step S105. On the other hand, when the calculated power factor λ is less than the threshold power factor λth, the power supply controller 14 returns to step S103. That is, the power supply controller 14 periodically calculates the power factor λ and compares the calculated power factor λ with the threshold power factor λth until the power factor λ becomes equal to or greater than the threshold power factor λth.

Here, as already described, the constant of the impedance converter 30 is such that the power factor λ approaches “1” when the relative position of the

resonators

13 and 23 is the reference position. Is set in correspondence with the input impedance of the primary-side resonator 13 when the relative position is the reference position. The input impedance of the primary side resonator 13 varies depending on whether or not the vehicle 100 (secondary side resonator 23) exists around the primary side resonator 13. Therefore, the power factor λ increases when the vehicle 100 exists around the primary side resonator 13, and decreases when the vehicle 100 does not exist around the primary side resonator 13. Therefore, the power factor λ being equal to or greater than the threshold power factor λth means that there is a high probability that the vehicle 100 exists around the primary side resonator 13. For this reason, the process of step S 104 can be said to be a determination process of whether or not the vehicle 100 exists around the primary side resonator 13. The power supply side controller 14 programmed to execute the process of step S104 functions as a “presence determining unit”.

Incidentally, the power factor λ when the vehicle 100 does not exist around the primary side resonator 13 (for example, within the wireless communication range of the power source side controller 14) under the situation where the power for temporary power transmission is output from the AC power source 12. It is defined as the first power factor. Further, the power factor λ when the relative position of the

resonators

13 and 23 is the reference position in a situation where temporary power transmission power is output from the AC power supply 12 is defined as a second power factor. In this case, the threshold power factor λth is arbitrary as long as it is a value between the first power factor and the second power factor. For example, a value between the average value of the first power factor and the second power factor and the first power factor may be employed as the threshold power factor λth.

The circumference of the primary side resonator 13 may be arbitrarily set as long as it is within the wireless communication range of the power supply side controller 14, but for example, within the range of a predetermined distance from the primary side resonator 13. It may be set. For example, the specific distance may be a distance at which the transmission efficiency between the

resonators

13 and 23 is greater than or equal to a predetermined threshold efficiency. In this case, the threshold power factor λth may be set to the power factor λ when the distance between the

resonators

13 and 23 is a specific distance in a situation where temporary power transmission power is output from the AC power supply 12. . In this case, when the power factor λ is equal to or higher than the threshold power factor λth, it means that the

resonators

13 and 23 may be arranged at positions where the transmission efficiency is equal to or higher than the threshold efficiency.

The surroundings of the primary resonator 13 are not limited to the above-described configuration, and may be, for example, a misalignment allowable range of the

resonators

13 and 23 that can output charging power from the AC power supply 12. The allowable misalignment range is a range in which the AC power supply 12 can output charging power, regardless of how the

resonators

13 and 23 are arranged within the allowable misalignment range. It is defined by the rating of the AC power supply 12. In this case, the threshold power factor λth is the minimum power factor when the power for temporary power transmission is output from the AC power supply 12 under the condition in which the

resonators

13 and 23 are arbitrarily arranged within the allowable range of displacement. It is good to be set to. In such a configuration, if the power factor λ is equal to or greater than the threshold power factor λth, there is a possibility that the secondary-side resonator 23 (vehicle 100) is disposed in a range in which the AC power supply 12 can output charging power. Means that. That is, in the process of step S104, is the secondary-side resonator 23 (power receiving device 21) present within a range in which the primary-side resonator 13 (power transmission device 11) can transmit AC power having a desired power value? It can also be said to be a process for determining whether or not.

In step S105 executed when it is determined that the vehicle 100 exists around the primary side resonator 13, the power supply side controller 14 stops the temporary power transmission and requests a movement stop request signal for requesting the vehicle 100 to stop moving. Send.

In subsequent step S106, the power supply side controller 14 shifts from the undetected state where the vehicle 100 is not detected to the temporarily detected state where the vehicle 100 is temporarily detected. In the temporary detection state, the power supply side controller 14 regulates communication so as not to perform communication with vehicles other than the vehicle 100 that is temporarily detected. The power supply controller 14 is in an undetected state in the initial state, and does not regulate communication in the undetected state.

Thereafter, in step S107, the power supply side controller 14 controls the switching relay 33 so that the primary side resonator 13 and the power reception detecting unit 32 are connected to each other. In step S 108, power supply-side controller 14 transmits a discharge request signal for requesting discharge to vehicle-side controller 26 of vehicle 100 that is temporarily detected. That is, the vehicle battery 22 is discharged when the vehicle 100 is present around the primary-side resonator 13.

In step S109, the power supply side controller 14 determines whether or not the received power is detected by the received power detection unit 32 within a predetermined period after transmitting the discharge request signal. The power supply side controller 14 programmed to execute the process of step S109 functions as a “transmission determination unit”.

Incidentally, “the received power is detected by the power receiving detection unit 32” means that the voltage value, current value, or power value of the received power detected by the power receiving detection unit 32 is greater than “0”, for example, A case where the power value of power is larger than a predetermined threshold power value is conceivable. As the threshold power value, for example, a value obtained by multiplying the power value of the discharge power of the vehicle battery 22 by a predetermined threshold transmission efficiency can be considered.

When the received power is detected within a predetermined period, power transmission from the secondary resonator 23 to the primary resonator 13 is performed, in other words, the primary resonator 13 and the secondary resonance. This means that power transmission is performed with the device 23. In this case, the power supply controller 14 makes a positive determination in step S109, and proceeds to step S110. In step S 110, the power supply controller 14 transmits a chargeable signal indicating that charging is possible to the vehicle controller 26. In step S111, the power supply controller 14 shifts from the temporary detection state to the main detection state, and ends the main charging preparation process. The power supply side controller 14 controls the AC power supply 12 so that the charging power is output from the AC power supply 12 until a predetermined charging end condition is satisfied based on the fact that the detection state is reached. Thereby, the charging power is transmitted from the primary side resonator 13 to the secondary side resonator 23.

The charge termination condition is, for example, when the state of charge of the vehicle battery 22 detected by the SOC sensor is in a predetermined state (full charge state) or when the power transmission device 11 is provided with a charge stop switch. This is a case where the charge stop switch is operated.

The power supply side controller 14 periodically grasps the power factor λ and the output power value of the AC / DC converter 12a during the output of the charging power, and determines whether at least one of these values is not an abnormal value. judge. When the power factor λ and the output power value of the AC / DC converter 12a are normal values, the power supply side controller 14 continues to output the charging power, and the power factor λ and the output of the AC / DC converter 12a. When the power value is an abnormal value, the output of the charging power is stopped.

If the received power is not detected within a predetermined period, it means that power transmission from the secondary resonator 23 to the primary resonator 13 is not performed, in other words, non-contact power transmission cannot be performed. To do. In this case, the power supply controller 14 makes a negative determination in step S109 and proceeds to step S112. In step S 112, the power supply side controller 14 transmits a charge impossible signal indicating that charging cannot be performed to the vehicle side controller 26. Then, in step S113, the power supply side controller 14 executes an abnormality handling process for notifying that charging cannot be performed, for example, and ends this charging preparation process.

Incidentally, the case where the received power is not detected within a predetermined period is, for example, that the power factor λ is equal to or greater than the threshold power factor λth for some reason even though the vehicle 100 does not exist around the primary side resonator 13. It is conceivable that the vehicle 100 in which the secondary resonator 23 is not mounted is present around the primary resonator 13 when it is erroneously determined. Further, for example, a case where foreign matter exists between the primary side resonator 13 and the secondary side resonator 23 can be considered.

Next, the charge preparation process performed by the vehicle side controller 26 is demonstrated. As already described, vehicle 100 is moving at the start of execution of the charging preparation process.
As shown in FIG. 2, first, in step S201, the vehicle-side controller 26 waits until it receives a movement stop request signal, and when it receives a movement stop signal, it proceeds to step S202 and receives the movement stop signal. The movement stop process is executed so that the vehicle 100 stops at the position where it is placed. As a specific configuration of the movement stop process, for example, it is conceivable to notify the car navigation display screen to stop on the spot. For example, when the vehicle 100 is equipped with an automatic stop function, the automatic stop function may be used to automatically stop the vehicle 100.

Thereafter, the vehicle-side controller 26 waits until receiving the discharge request signal in step S203. If the discharge request signal is received, the vehicle-side controller 26 proceeds to step S204, and the power converter 24 changes the secondary-side resonator 23. The power conversion unit 24 and the vehicle battery 22 are controlled so that alternating current power is output. The power value of the AC power output from the power conversion unit 24 toward the secondary-side resonator 23 is arbitrary, and may be the same as or different from the power value of the temporary power transmission. .

After the discharge is started, the vehicle-side controller 26 waits until it receives a chargeable signal or an unchargeable signal in step S205, and if it receives a chargeable signal or an unchargeable signal, it proceeds to step S206. Then, the discharge of the vehicle battery 22 is stopped. And the vehicle side controller 26 performs a signal corresponding | compatible process in step S207, and complete | finishes this charge preparation process. In the signal handling process, for example, when a chargeable signal is received, various processes for starting charging are executed, and when a charge impossible signal is received, a process such as notification that charging cannot be performed Is executed.

Next, the operation of this embodiment will be described with reference to FIGS. For convenience of explanation, it is assumed that the primary side resonator 13 is installed on the ground, and the secondary side resonator 23 is provided at the bottom of the vehicle 100. In this case, the reference position is, for example, a position where the

resonators

13 and 23 face each other in the vertical direction.

As shown in FIGS. 3A and 3B, the vehicle 100 on which the secondary side resonator 23 (power receiving device 21) is mounted enters the periphery of the primary side resonator 13, and each resonator 13. , 23 is placed at the reference position, as shown in FIG. 4A, the power factor λ increases and becomes equal to or greater than the threshold power factor λth. Thereby, the connection destination of the primary side resonator 13 becomes the power reception detection unit 32. Then, discharging of the vehicle battery 22 is started, and AC power is input to the secondary resonator 23. In this case, the received power is detected by the received power detection unit 32 as shown in FIG. On condition that the received power is detected, the vehicle battery 22 is charged using the charging power.

According to the embodiment described above in detail, the following effects are obtained.
(1) In the power transmission device 11 having the AC power supply 12 and the primary side resonator 13 (primary side coil 13a), the primary side resonator 13 receives power from the secondary side resonator 23 (secondary side coil 23a). A power reception detection unit 32 that detects AC power is provided. The power transmission device 11 includes a power source controller 14 that determines whether or not the vehicle 100 on which the power receiving device 21 is mounted is present around the primary resonator 13. When the AC power is input to the secondary side resonator 23 when the vehicle 100 is determined to be present around the primary side resonator 13, the power source side controller 14 receives the power reception detection unit 32. Based on the detection result, a transmission determination is made as to whether or not power transmission from the secondary resonator 23 to the primary resonator 13 is being performed. Thereby, it can be grasped suitably whether electric power transmission is performed between the

resonators

13 and 23. In other words, the vehicle 100 in which the power transmission device 11 can perform non-contact power transmission can be properly grasped.

More specifically, the power factor λ may be erroneously determined to be equal to or greater than the threshold power factor λth regardless of whether the vehicle 100 is not present around the primary resonator 13 due to some factor such as noise. Further, the power factor λ may be greater than or equal to the threshold power factor λth due to the presence of foreign objects other than the vehicle 100, the vehicle 100 on which the power receiving device 21 is not mounted, etc. around the primary side resonator 13. In this case, when the transmission of the charging power is started as it is, not only is a wasteful power loss, but an excessive load is applied to the AC power supply 12. However, if it is configured to omit the presence determination and perform only the transmission determination, it is necessary to discharge the vehicle battery 22 from the stage before the vehicle 100 stops, and thus the discharge period tends to be long. For this reason, the power consumption of the vehicle battery 22 required for transmission determination tends to increase. On the other hand, according to the present embodiment, since the presence determination is first performed and the transmission determination is performed when the presence determination is an affirmative determination, the above inconvenience can be suppressed.

(2) The power supply side controller 14 determines whether or not the vehicle 100 exists around the primary side resonator 13 based on the fluctuation of the power factor λ. Thereby, presence determination can be performed without providing a dedicated sensor such as a vehicle detection sensor.

In particular, the power factor λ is a parameter grasped by the power transmission device 11. For this reason, the power source side controller 14 can perform the presence determination without performing communication with the vehicle side controller 26.

Further, the power supply side controller 14 periodically grasps the power factor λ and the output power value of the AC / DC converter 12a during the output of the charging power, and when at least one of these values is an abnormal value, Stop charging power output. That is, the parameter used for presence determination and the parameter used for power transmission abnormality determination are shared. Thereby, simplification of a structure can be achieved.

(3) The AC power supply 12 includes an AC / DC converter 12a (first conversion unit) that converts external power into DC power, and a DC / AC converter 12b (second conversion unit) that converts the DC power into AC power. ). And the power transmission apparatus 11 detects the output current value of the switching relay 33 which switches the connection destination of the primary side resonator 13 to the AC / DC converter 12a or the power receiving detection part 32, and at least AC / DC converter 12a. A power transmission detection unit 31. When the presence determination is performed, the power supply side controller 14 as the switching control unit is configured such that when the transmission determination is performed such that the connection destination of the primary resonator 13 is the DC / AC converter 12b, The switching relay 33 is controlled so that the connection destination of the primary side resonator 13 is the power reception detection unit 32.

According to this configuration, when presence determination is performed, the connection destination of the primary-side resonator 13 is the DC / AC converter 12b. Note that the connection destination of the primary side resonator 13 is the DC / AC converter 12b through a mode in which the primary side resonator 13 and the DC / AC converter 12b are directly connected, and an optional component. Including a mode of being indirectly connected. In this case, based on the detection result of the power transmission detection unit 31, it can be determined whether or not the vehicle 100 exists around the primary side resonator 13. In particular, the power transmission detection unit 31 detects the output current value of the AC / DC converter 12a. Since the output current value of the AC / DC converter 12a is a direct current value, it can be detected relatively easily and accurately as compared with the alternating current value. Therefore, the presence determination can be suitably performed by using the output current value of the AC / DC converter 12a.

It is also conceivable that the power transmission detection unit 31 tries to detect the received power. However, in order for the power transmission detection unit 31 to detect the received power, it is necessary to convert the received power into DC power by the DC / AC converter 12b. That is, the DC / AC converter 12b needs to be configured to be capable of bidirectional conversion between DC power and AC power. Adopting such a power converter capable of bidirectional conversion is not preferable from the viewpoint of complication of the configuration and enlargement of the power transmission device 11.

On the other hand, in the present embodiment, a power reception detection unit 32 is provided separately from the power transmission detection unit 31, and switching to switch the connection destination of the primary-side resonator 13 to the DC / AC converter 12b or the power reception detection unit 32 is performed. A relay 33 is provided. And the connection destination of the primary side resonator 13 is switched between presence determination and transmission determination. As a result, it is possible to suitably perform the presence determination and the transmission determination while avoiding the above inconvenience.

(4) When the presence determination is performed, the power supply side controller 14 controls the AC power supply 12 so that the temporary power transmission power having a power value smaller than the charging power is output from the AC power supply 12. Thereby, reduction of electric power loss and the burden reduction of AC power supply 12 can be aimed at.

(5) The power transmission device 11 includes an impedance converter 30 that is provided between the AC power supply 12 and the primary-side resonator 13 and performs impedance conversion. The constant (impedance) of the impedance converter 30 is such that the power factor λ is “1” in a situation where charging power is output from the AC power supply 12 and the relative positions of the

resonators

13 and 23 are the reference positions. Is set to approach. Thereby, electric power transmission by the electric power for charge can be performed suitably.

Here, when the constant of the impedance converter 30 is set so as to correspond to the charging power as described above, the power factor in a situation where temporary transmission power having a power value different from that of the charging power is output. λ becomes lower. In this case, the variation amount of the power factor λ that varies depending on whether or not the vehicle 100 (secondary resonator 23) is present around the primary resonator 13 tends to be small. For this reason, an erroneous determination is likely to occur in the presence determination using the power factor λ. However, if the presence determination using the charging power is performed, the effect of (4) cannot be obtained. In contrast, in the present embodiment, when the presence determination is an affirmative determination, the power transmission by the charging power can be performed while the power transmission by the charging power can be suitably performed by further performing the transmission determination. The above-mentioned inconveniences that can be caused by suitably performing can be preferably avoided.

In addition, you may change the said embodiment as follows.
In the embodiment, the power factor λ is employed as a parameter for determining whether or not the vehicle 100 on which the power receiving device 21 is mounted is present around the primary-side resonator 13, but is not limited thereto. The parameter may be, for example, the output power value of the AC / DC converter 12a or the output current value instead of the power factor λ. The parameter may be an output power value of the DC / AC converter 12b or an output current value. In the output power value of the DC / AC converter 12b, the parameter may be active power or apparent power. Further, the parameter may be a difference between the output current value of the AC / DC converter 12a and the output current value of the DC / AC converter 12b. Further, when the AC power supply 12 is not a voltage source but a current source, the parameter may be an input voltage value or an output voltage value of the DC / AC converter 12b. However, from the viewpoint of common use with the power transmission abnormality determination, the parameter is preferably the power factor λ or the output power value of the DC / AC converter 12b.

In short, the power supply side controller 14 may perform the presence determination based on the fluctuation of at least one of the voltage value and the current value in the power transmission device 11. At least one of the voltage value and the current value in the power transmission device 11 can be said to be at least one of a voltage value and a current value at a predetermined position on the power transmission path from the AC / DC converter 12a to the primary side resonator 13, for example. .

Further, the power supply side controller 14 may determine that the vehicle 100 exists around the primary side resonator 13 by performing wireless communication with the vehicle side controller 26. Further, the vehicle-side controller 26 may be configured to transmit a power reception confirmation signal indicating that power is received when AC power is received by the secondary-side resonator 23. In this case, the power supply side controller 14 may determine that the vehicle 100 exists around the primary side resonator 13 based on the reception of the power reception confirmation signal.

Further, the power transmission device 11 may include a vehicle detection sensor that detects the vehicle 100 existing around the primary side resonator 13. In this case, when the vehicle 100 is detected by the vehicle detection sensor, the processes after step S105 may be executed. According to such a configuration, the vehicle detection sensor can detect the vehicle 100 relatively easily, but it is difficult to determine whether or not the power receiving device 21 is mounted on the vehicle 100. For this reason, even if it is a case where the vehicle 100 in which the power receiving apparatus 21 is not mounted is detected, there exists a possibility that the output of the electric power for charging may be performed. On the other hand, by performing transmission determination after the presence determination is performed, even if the vehicle detection sensor detects the vehicle 100 on which the power receiving device 21 is not mounted, the output of charging power is output. You can prevent it from happening. Although the specific configuration of the vehicle detection sensor is arbitrary, for example, a range sensor that performs laser scanning on a region around the primary-side resonator 13 is conceivable.

○ The power transmission detection unit 31 and the power reception detection unit 32 are provided separately, but are not limited thereto, and may be integrated. For example, as illustrated in FIG. 5, a power transmission / reception detection unit 41 may be provided instead of the power transmission detection unit 31, and the power reception detection unit 32 and the switching relay 33 may be omitted. In this case, in place of the DC / AC converter 12b, a bidirectional converter 42 capable of bidirectional conversion between DC power and AC power may be provided. Thereby, the received power can be detected by the power transmission / reception detection unit 41. The specific configuration of the power transmission / reception detection unit 41 is the same as that of the power transmission detection unit 31.

In the embodiment, the power transmission detection unit 31 detects the output voltage value and output current value of the AC / DC converter 12a and the output current value of the DC / AC converter 12b. Instead, only one of them may be detected. In this case, the configuration can be simplified.

○ Positioning of the vehicle 100 may be performed using the received power that is the AC power received by the primary-side resonator 13. Specifically, for example, the power supply controller 14 may guide the vehicle 100 so that the power value of the received power detected by the power reception detection unit 32 is increased.

○ A plurality of impedance converters 30 may be provided. Further, the power receiving device 21 may be provided with an impedance converter. Further, the impedance converter 30 may be omitted.

In the presence determination, the temporary power transmission power is used, but the present invention is not limited to this, and charging power may be used.
In the embodiment, the external power is system power, but is not limited thereto, and may be DC power. In this case, the AC / DC converter 12a may be omitted, or a DC / DC converter may be provided in place of the AC / DC converter 12a. In this example, the DC / DC converter corresponds to the first conversion unit.

○ The execution subject of transmission determination is arbitrary, and may be, for example, the vehicle-side controller 26, or a dedicated controller different from the

controllers

14 and 26. In this case, the power supply side controller 14 may appropriately transmit information necessary for transmission determination, for example, information related to the detection result of the power reception detection unit 32 to the execution subject of transmission determination.

○ When the vehicle 100 has entered the wireless communication range of the power supply side controller 14 as a trigger for executing the charging preparation process, the communication establishment state in which the

controllers

14 and 26 have authenticated each other as communication partners You may adopt the case. The communication established state is a state in which communication with an authenticated controller is performed, but communication with a controller other than the authenticated controller is restricted.

O It may be adopted that the vehicle 100 is stopped as an execution opportunity of the charge preparation process. In this case, when the power factor λ is less than the threshold power factor λth, the power supply controller 14 may make a movement request so that the power factor λ is equal to or greater than the threshold power factor λth. The movement request may be, for example, a notification that prompts movement, or a signal that moves the vehicle 100 to the vehicle-side controller 26.

The secondary side detection unit 25 may detect DC power between the power conversion unit 24 and the vehicle battery 22.
The switching relay 33 may be provided between the AC power supply 12 and the impedance converter 30.

The power reception detecting unit 32 may have any specific configuration as long as it can detect a physical quantity related to the received power, for example, at least one of a voltage value and a current value of the received power.
The power supply side controller 14 grasps in advance the power factor λ when the vehicle 100 is not present as a reference value, and in step S104, the difference between the power factor λ calculated in step S103 and the reference value is determined in advance. It may be determined whether or not it is equal to or greater than the threshold value. In this case, the power supply controller 14 determines that the vehicle 100 exists when the difference between the power factor λ calculated in step S103 and the reference value is equal to or greater than a predetermined threshold.

○ The threshold power factor λth may be set in consideration of a time lag from when the positive determination is made in step S104 until the vehicle 100 stops. Specifically, for example, a distance that the vehicle 100 can move during the time lag is defined as a time lag distance. In this case, a range of a distance longer than the distance (specific distance) at which the transmission efficiency between the

resonators

13 and 23 is equal to or greater than a predetermined threshold efficiency is set as the periphery of the primary-side resonator 13. The threshold power factor λth may be set in correspondence with the range. Similarly, a range wide by the time lag distance with respect to the positional deviation allowable range may be set around the primary-side resonator 13 and the threshold power factor λth may be set in correspondence with the range.

The AC power supply 12 is not limited to a voltage source, and may be a power source or a current source.
The AC power supply 12 is configured to be capable of outputting a plurality of types of AC power having different power values, but is not limited thereto, and may output only one type of AC power (for example, charging power). Good.

The resonance frequency of the primary side resonator 13 and the resonance frequency of the secondary side resonator 23 are set to be the same. However, the present invention is not limited to this, and both may be made different within a power transmission range. .
O Although the primary side resonator 13 and the secondary side resonator 23 were the same structures, it is not restricted to this, A different structure may be sufficient.

Each capacitor 13b, 23b may be omitted. In this case, magnetic field resonance is performed using the parasitic capacitances of the coils 13a and 23a.
○ The power receiving device 21 may be mounted on any object, and may be mounted on, for example, a robot or an electric wheelchair.

In the embodiment, the primary coil 13a and the primary capacitor 13b are connected in parallel. However, the present invention is not limited to this, and both may be connected in series. Similarly, the secondary coil 23a and the secondary capacitor 23b may be connected in series.

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 AC power received by the secondary resonator 23 is used for charging the vehicle battery 22, but is not limited thereto, and may be used for other purposes.

The primary side resonator 13 may have a resonance circuit composed of the primary side coil 13a and the primary side capacitor 13b, and a primary side coupling coil that is coupled to the resonance circuit by electromagnetic induction. Similarly, the secondary side resonator 23 may include a resonance circuit including a secondary side coil 23a and a secondary side capacitor 23b, and a secondary side coupling coil coupled to the resonance circuit by electromagnetic induction.

In the embodiment, each of the power supply side controller 14 and the vehicle side controller 26 that function as the presence determination unit and the transmission determination unit is configured by an arbitrary programmed electric circuit (circuitry) such as a microcomputer, a processor, and an electronic control unit. May be.

In the embodiment, each of the secondary side detection unit 25, the power transmission detection unit 31, and the power reception detection unit 32 may be configured by a detector or a sensor that includes only hardware, or from a combination of hardware and software. It may be constituted by a detector or a sensor.

Next, preferred technical ideas that can be grasped from the embodiment and other examples will be described below.
(1) A first AC power source that outputs AC power, and a power transmission device having a primary coil to which AC power is input from the first AC power source,
A secondary coil configured to contactlessly receive AC power input from the first AC power source to the primary coil; and a second coil that outputs AC power to the secondary coil. A power receiving device having an AC power source;
A power reception detection unit that is provided in the power transmission device and that detects AC power received by the primary coil in a non-contact manner from the secondary coil;
A controller provided in the power transmission device,
The controller is
It is programmed to determine whether or not an object on which the power receiving device is mounted exists around the primary coil, and it is determined that the object exists around the primary coil. When AC power is input from the second AC power source to the secondary coil using the trigger as a trigger, power transmission from the secondary coil to the primary coil based on the detection result of the power reception detection unit A non-contact power transmission device programmed to determine whether or not is being performed.

(2) a first AC power source that outputs AC power;
A primary coil to which AC power is input from the first AC power source;
A controller,
Power transmission configured to contactlessly transmit AC power to the secondary coil of a power receiving device having a secondary coil and a second AC power source that outputs AC power to the secondary coil. Equipment,
The power transmission device includes a power reception detection unit that detects AC power received by the primary coil in a non-contact manner from the secondary coil,
The controller is
It is programmed to determine whether or not an object on which the power receiving device is mounted exists around the primary coil, and it is determined that the object exists around the primary coil. When AC power is input from the second AC power source to the secondary coil using the trigger as a trigger, power transmission from the secondary coil to the primary coil based on the detection result of the power reception detection unit A power transmission device that is programmed to determine whether or not is being performed.

Claims

A first AC power source that outputs AC power, and a power transmission device having a primary coil to which AC power is input from the first AC power source;
A secondary coil configured to contactlessly receive AC power input from the first AC power source to the primary coil; and a second coil that outputs AC power to the secondary coil. A power receiving device having an AC power source;
A power reception detection unit that is provided in the power transmission device and that detects AC power received by the primary coil in a non-contact manner from the secondary coil;
A presence determination unit that determines whether an object on which the power receiving device is mounted is present around the primary coil;
When the presence determination unit determines that the object is present around the primary coil, the AC detection is performed when AC power is input from the second AC power source to the secondary coil. A transmission determination unit that determines whether or not power transmission from the secondary side coil to the primary side coil is performed based on a detection result of the unit;
A non-contact power transmission device.
The said presence determination part determines whether the said target exists around the said primary side coil based on the fluctuation | variation of at least one of the voltage value in the said power transmission apparatus, and an electric current value. Non-contact power transmission device.
The AC power supply is
A first converter that converts external power into DC power;
DC power is input from the first converter and a second converter that converts the DC power into AC power;
With
The power transmission equipment is
A switching unit that switches the connection destination of the primary coil to the second conversion unit or the power reception detection unit;
A power transmission detector that detects at least one of an output voltage value and an output current value of the first converter;
With
The presence determination unit is configured to determine whether or not the object exists around the primary coil based on a detection result of the power transmission detection unit,
When the determination by the presence determination unit is performed, the non-contact power transmission device controls the switching unit so that a connection destination of the primary coil is the second conversion unit, and the transmission determination unit 3. The contactless power transmission device according to claim 2, further comprising: a switching control unit that controls the switching unit so that a connection destination of the primary coil is the power reception detection unit when the determination is performed according to 3. .
The presence determination unit is configured to determine whether or not the object is present around the primary side coil based on a variation in power factor.
The power transmission device includes an impedance conversion unit that is provided between the AC power source and the primary coil and performs impedance conversion.
The impedance converter outputs AC power having a predetermined specific power value from the AC power source, and a relative position between the primary side coil and the secondary side coil is a predetermined reference position. The contactless power transmission device according to claim 1, wherein the input impedance of the primary coil is impedance-converted so that the power factor approaches 1 when the power factor is low.
A first AC power source that outputs AC power;
A primary coil to which AC power is input from the first AC power source;
Power transmission configured to contactlessly transmit AC power to the secondary coil of a power receiving device having a secondary coil and a second AC power source that outputs AC power to the secondary coil. In the equipment
A power reception detection unit that detects AC power received by the primary coil in a non-contact manner from the secondary coil;
A presence determination unit that determines whether an object on which the power receiving device is mounted is present around the primary coil;
With
When the presence determination unit determines that the object is present around the primary coil, the AC detection is performed when AC power is input from the second AC power source to the secondary coil. A power transmission device that determines whether or not power transmission from the secondary coil to the primary coil is performed based on a detection result of the unit.