JP2013070514A - Electric vehicle and power transmission system - Google Patents

Abstract

An electric vehicle capable of extending a cruising distance during platooning and an electric power transmission system using the electric vehicle are provided.
An electric vehicle 10 capable of running in a platoon includes power transmission / reception units 12, 14, a power storage unit 16, a power conversion unit 18, a connection unit 20, and an ECU 22. The power conversion unit 18 is connected to the power storage unit 16 and is configured to be capable of bidirectional power conversion. The power transmission / reception units 12 and 14 are used for exchanging electric power in a non-contact manner with the first and second vehicles adjacent to each other during platooning. The connection unit 20 selectively connects any two of the power transmission / reception units 12 and 14 and the power conversion unit 18. The ECU 22 controls the power conversion unit 18 and the connection unit 20.
[Selection] Figure 1

Description

  The present invention relates to an electric vehicle and an electric power transmission system, and more particularly to an electric vehicle capable of running in a row in which a plurality of vehicles run while maintaining a predetermined inter-vehicle distance, and an electric power transmission system using the electric vehicle.

  Japanese Patent Laying-Open No. 9-293194 (Patent Document 1) discloses a vehicle group traveling system in which a leading vehicle and a plurality of following vehicles travel in a row (convoy traveling). In this system, the leading vehicle transmits to the following vehicle at predetermined intervals. When each following vehicle receives information from the preceding vehicle, each following vehicle returns to the preceding vehicle and transmits information from the preceding vehicle to the following vehicle. Then, each following vehicle transmits the reply information from the following vehicle to the preceding vehicle at the next response to the preceding vehicle, and if there is no response from the following vehicle, it recognizes its own vehicle as the last vehicle And reply to the car ahead.

  As a result, it is possible to efficiently transmit information to each subsequent vehicle using the leading vehicle as a synchronization source, and the leading vehicle can confirm that information has been normally transmitted to the last car. (See Patent Document 1).

Japanese Patent Laid-Open No. 9-293194 Japanese Patent Laying-Open No. 2005-210843 JP 2010-219838 A

  If any of the electric vehicles running in a platoon runs out of running power stored in the power storage unit, platooning is not possible in other electric vehicles even if there is a surplus of power. For platooning, it is a challenge to extend the cruising distance as much as possible, because benefits such as reducing labor costs by placing drivers only on the leading vehicle and improving fuel efficiency by reducing air resistance during driving can be obtained. However, the above-mentioned publication does not particularly examine such a problem and its solution.

  Therefore, an object of the present invention is to provide an electric vehicle capable of extending a cruising distance during platooning and an electric power transmission system using the electric vehicle.

  According to the present invention, the electric vehicle includes the power receiving device and the power transmission device. The power receiving device is configured to be capable of receiving power from the outside of the vehicle without contact. The power transmission device is configured to transmit power received by the power reception device to the outside of the vehicle.

  Preferably, the electric vehicle further includes a rechargeable power storage unit, a power conversion unit, a connection unit, and a control unit. The power storage unit stores the power received by the power receiving device. The power conversion unit is connected to the power storage unit and configured to be capable of converting power in both directions. The connection unit selectively connects any two of the power receiving device, the power transmission device, and the power conversion unit. The control unit controls the power conversion unit and the connection unit.

  More preferably, when power transmission from the power reception device to the power transmission device is requested, the control unit controls the connection unit to electrically connect the power reception device to the power transmission device.

  Preferably, the power receiving device is configured to receive power in a non-contact manner from a first vehicle adjacent to the electric vehicle. The power transmission device is configured to be able to transmit power to a second vehicle adjacent to the electric vehicle without contact.

  More preferably, the power reception device is configured to be able to receive power from the first vehicle in a non-contact manner during a platooning in which a plurality of vehicles travel while maintaining a predetermined inter-vehicle distance. The power transmission device is configured to be able to transmit power to the second vehicle in a contactless manner when traveling in a row.

  Preferably, the power receiving device is disposed at one of the vehicle frontmost portion and the vehicle rearmost portion, and the power transmission device is disposed at the other of the vehicle frontmost portion and the vehicle rearmost portion.

  Preferably, the difference between the natural frequency of the power receiving device and the natural frequency of the power transmitting unit configured to transmit power to the power receiving device in the first vehicle is equal to the natural frequency of the power receiving device or the natural frequency of the power transmitting unit in the first vehicle. ± 10% or less. In addition, the difference between the natural frequency of the power transmission device and the natural frequency of the power receiving unit configured to receive power from the power transmission device in the second vehicle is the difference between the natural frequency of the power transmission device or the natural frequency of the power receiving unit in the second vehicle. ± 10% or less.

  More preferably, each of the coupling coefficient between the power reception device and the power transmission unit of the first vehicle and the coupling coefficient between the power transmission device and the power reception unit of the second vehicle are 0.1 or less.

  More preferably, the power reception device is formed between the power reception device and the power transmission unit of the first vehicle, and is between the magnetic field that vibrates at a specific frequency and between the power reception device and the power transmission unit of the first vehicle. The power is received from the power transmission unit of the first vehicle through at least one of the electric field that is formed and vibrates at a specific frequency. The power transmission device is formed between the power transmission device and the power receiving unit of the second vehicle, and is formed between the magnetic field that vibrates at a specific frequency, the power transmission device and the power receiving unit of the second vehicle, and Then, power is transmitted to the power receiving unit of the second vehicle through at least one of the electric field that vibrates at a specific frequency.

  Preferably, the power receiving device is further configured to be able to transmit power to the outside of the vehicle without contact. The power transmission device is further configured to receive power from the outside of the vehicle without contact.

  Preferably, the power receiving device is configured to be able to receive power in a non-contact manner from a power supply facility provided outside the vehicle. The power transmission device is configured to be able to transmit power to a vehicle adjacent to the electric vehicle without contact.

  According to the invention, the power transmission system includes a plurality of vehicles and a planning unit. Each of the plurality of vehicles is any one of the electric vehicles described above. The planning unit plans power transmission between a plurality of vehicles using dynamic programming. In each of the plurality of vehicles, the control unit controls the power conversion unit and the connection unit based on the calculation result of the planning unit.

  Preferably, the power transmission system further includes a notification unit. The notification unit notifies the users of the plurality of vehicles when there is a vehicle that cannot reach the destination among the plurality of vehicles as a result of the calculation by the planning unit.

  According to the invention, the power transmission system includes a plurality of vehicles and a planning unit. Each of the plurality of vehicles is any one of the electric vehicles described above. The planning unit plans power transmission between a plurality of vehicles. Then, the planning unit calculates the travelable distance of each vehicle when power transmission is not performed between the plurality of vehicles, and when there is a vehicle that cannot reach the destination among the plurality of vehicles, the planning unit has reached the destination Calculate the energy margin of each vehicle at the time, and transfer power from the nearest vehicle that cannot afford to reach the destination to the vehicle that cannot reach the destination when it reaches the destination. To plan power transmission between multiple vehicles.

  In this invention, the power receiving device is configured to be able to receive power from the outside of the vehicle without contact, and the power transmitting device is configured to be able to transmit the power received by the power receiving device to the outside of the vehicle. Electric power can be exchanged between vehicles traveling in a platoon when traveling in a platoon traveling while maintaining a predetermined inter-vehicle distance. Thereby, electric power can be transmitted from a vehicle having sufficient power to a vehicle having no margin. Therefore, according to the present invention, the cruising distance during platooning can be extended.

1 is an overall configuration diagram of an electric vehicle according to Embodiment 1 of the present invention. It is a circuit diagram which shows an example of the circuit structure of a connection part. It is the top view which showed an example of the structure of a connection part. It is the figure which showed the flow of the electric power at the time of RF mode. It is the figure which showed the flow of the electric power at the time of TF mode. It is the figure which showed the flow of the electric power at the time of RR mode. It is the figure which showed the flow of the electric power at the time of TR mode. It is the figure which showed the flow of the electric power at the time of TH mode. It is the figure which showed an example of the electric power transmission between vehicles at the time of platooning. It is the figure which showed the other example of the electric power transmission between vehicles at the time of platooning. It is the figure which showed the simulation model of the electric power transmission system. It is the figure which showed the relationship between the shift | offset | difference of the natural frequency of a power transmission part and a power receiving part, and electric power transmission efficiency. It is an equivalent circuit diagram when electric power is transmitted between two adjacent electric vehicles. It is the figure which showed the relationship between the distance from an electric current source (magnetic current source), and the intensity | strength of an electromagnetic field. It is a functional block diagram which shows the function of ECU when an electric vehicle becomes a master vehicle at the time of platooning. It is a functional block diagram which shows the function of ECU when an electric vehicle is a slave vehicle at the time of platooning. It is a flowchart for demonstrating the process sequence of the electric power transmission plan between vehicles performed by ECU at the time of platooning. 6 is a flowchart for illustrating a processing procedure of electric power transmission between vehicles executed by an ECU in the second embodiment. FIG. 6 is an overall configuration diagram of an electric vehicle according to a third embodiment.

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

[Embodiment 1]
FIG. 1 is an overall configuration diagram of an electric vehicle according to Embodiment 1 of the present invention. Referring to FIG. 1, an electric vehicle 10 includes a power transmission / reception unit 12, 14, a power storage unit 16, a power generation unit 17, a power conversion unit 18, a connection unit 20, an electronic control unit (hereinafter referred to as “ECU”). Electronic Control Unit) ”)) 22 and a communication unit 24.

  The electric vehicle 10 is capable of running in a row (also referred to as convoy travel) in which a plurality of vehicles travel while maintaining a predetermined inter-vehicle distance. The power transmission / reception unit 12 is provided to exchange electric power in a contactless manner with a vehicle (hereinafter referred to as a “front vehicle”) that travels in front of the electric vehicle 10 during platooning. Specifically, the power transmission / reception unit 12 is disposed in the foremost part of the vehicle. When power transmission from the electric vehicle 10 to the front vehicle is requested during the platooning, the power transmission / reception unit 12 receives the electric power received from the connection unit 20 at the rear part of the front vehicle (not shown). Without contact). Further, when power transmission from the front vehicle to the electric vehicle 10 is requested during platooning, the power transmission / reception unit 12 receives the power output from the power transmission / reception unit disposed at the rearmost part of the front vehicle in a non-contact manner. To do. As an example, the power transmission / reception unit 12 includes a resonance circuit including a coil and a capacitor. The power transmission / reception unit 12 will be described in detail later.

  The power transmission / reception unit 14 is provided for exchanging electric power in a contactless manner with a vehicle (hereinafter referred to as a “rear vehicle”) that travels behind one electric vehicle 10 during the platooning. Specifically, the power transmission / reception unit 14 is disposed at the rearmost part of the vehicle. When power transmission from the electric vehicle 10 to the rear vehicle is requested during the platooning, the power transmission / reception unit 14 receives the power received from the connection unit 20 at the frontmost part of the rear vehicle (not shown). Without contact). Further, when power transmission from the rear vehicle to the electric vehicle 10 is requested during platooning, the power transmission / reception unit 14 receives the power output from the power transmission / reception unit disposed in the foremost part of the rear vehicle in a contactless manner. To do. As an example, the power transmission / reception unit 14 is also configured by a resonance circuit including a coil and a capacitor. The power transmission / reception unit 14 will also be described in detail later.

  The power storage unit 16 is a rechargeable DC power source, and is configured by a secondary battery such as nickel hydride or lithium ion, for example. The power storage unit 16 stores electric power for traveling. Then, the power storage unit 16 supplies the stored power to the power generation unit 17 and is charged by receiving the power generated by the power generation unit 17. Furthermore, during platooning, the power storage unit 16 can supply the stored power to the power conversion unit 18 to supply power to the front vehicle or the rear vehicle, and the power received from the front vehicle or the rear vehicle. Can be received from the power converter 18 and charged. Note that a large-capacity capacitor can be used as the power storage unit 16, and any power buffer can be used as long as it can temporarily store power and output the stored power.

  The power generation unit 17 includes an inverter and an electric motor (not shown), receives electric power from the power storage unit 16, and generates a driving force. When the vehicle is braked, the power generation unit 17 converts the kinetic energy of the vehicle into electric power by the electric motor and outputs the electric power to the power storage unit 16. The power generation unit 17 may include an engine (not shown), and may further include a generator that can generate power using the output of the engine and charge the power storage unit 16.

  The power conversion unit 18 converts the power output from the power storage unit 16 into high-frequency AC in accordance with a control command received from the ECU 22, and the converted high-frequency AC power is transmitted / received by the power transmission / reception unit 12 or power transmission / reception via the connection unit 20. To the unit 14. The power conversion unit 18 converts AC power received by the power transmission / reception unit 12 or the power transmission / reception unit 14 and received via the connection unit 20 into direct current according to a control command from the ECU 22, and outputs the direct current to the power storage unit 16. The power conversion unit 18 is configured by, for example, a single-phase bridge inverter.

  Connection unit 20 selectively electrically connects any two of power transmission / reception unit 12, power transmission / reception unit 14, and power conversion unit 18 in accordance with a switching command received from ECU 22.

  FIG. 2 is a circuit diagram illustrating an example of a circuit configuration of the connection unit 20. Referring to FIG. 2, connection unit 20 includes switches 30, 32, 34 and terminals 36, 38, 40. Terminals 36, 38, and 40 are connected to power conversion unit 18, power transmission / reception unit 12, and power transmission / reception unit 14, respectively. The switch 30 is connected between the terminals 36 and 38. The switch 32 is connected between the terminals 36 and 40. The switch 34 is connected between the terminals 38 and 40.

  Each of the switches 30, 32, and 34 is configured by a relay or a semiconductor switch, and is on / off controlled in accordance with a switching command from the ECU 22 (FIG. 1). When the switch 30 is turned on and the switches 32 and 34 are turned off, the power transmission / reception unit 12 and the power conversion unit 18 are electrically connected. Further, when the switch 32 is turned on and the switches 30 and 34 are turned off, the power transmission / reception unit 14 and the power conversion unit 18 are electrically connected. When the switch 34 is turned on and the switches 30 and 32 are turned off, the power transmission / reception unit 12 and the power transmission / reception unit 14 are electrically connected, and the power conversion unit 18 is electrically connected from the connection unit 20. Disconnected.

  FIG. 3 is a plan view showing an example of the structure of the connecting portion 20. Referring to FIG. 2 together with FIG. 3, the switches 30, 32, 34 are stored in the case 44. The terminals 36, 38 and 40 are constituted by connectors. The terminal 36 is connected to the switches 30 and 32, the terminal 38 is connected to the switches 30 and 34, and the terminal 40 is connected to the switches 32 and 34 (wiring is not shown). The connector part 42 is a signal terminal for receiving a switching command from the ECU 22 (FIG. 1).

  Referring to FIG. 1 again, ECU 22 performs power conversion unit 18 and connection unit by software processing by executing a program stored in advance by a CPU (Central Processing Unit) and / or hardware processing by a dedicated electronic circuit. 20 and the power generation unit 17 are controlled.

  Specifically, during platooning, the ECU 22 generates power while communicating with other vehicles by the communication unit 24 so that the electric vehicle 10 runs while maintaining a predetermined distance between the front vehicle and / or the rear vehicle. The unit 17 is controlled.

  Further, when power transmission is performed between the vehicles during the platooning, the ECU 22 performs power transmission in one of the following five modes in accordance with a power transmission plan to be described later, and the power conversion unit 18 and the connection unit 20. To control. Specifically, the five modes are the forward power reception mode (RF mode), the forward power transmission mode (TF mode), the rear power reception mode (RR mode), the rear power transmission mode (TR mode), and the passing mode (TH mode). It is.

  FIG. 4 is a diagram showing the flow of power in the RF mode. Referring to FIG. 1 together with FIG. 4, in the RF mode, power is received by the power transmission / reception unit 12 from the vehicle ahead without contact, and the received power is supplied to the power storage unit 16. In the RF mode, the ECU 22 controls the connection unit 20 so as to electrically connect the power transmission / reception unit 12 and the power conversion unit 18, and converts the AC power received from the power transmission / reception unit 12 through the connection unit 20 into direct current. The power conversion unit 18 is controlled so as to be converted and output to the power storage unit 16.

  FIG. 5 is a diagram showing the flow of power in the TF mode. Referring to FIG. 1 together with FIG. 5, in the TF mode, power is supplied from power storage unit 16 to power transmission / reception unit 12, and power is transmitted to front vehicle by power transmission / reception unit 12 in a contactless manner. In the TF mode, the ECU 22 controls the connection unit 20 so as to electrically connect the power transmission / reception unit 12 and the power conversion unit 18, and converts the power output from the power storage unit 16 into a high-frequency alternating current for connection. The power conversion unit 18 is controlled to be supplied to the power transmission / reception unit 12 via the unit 20.

  FIG. 6 is a diagram showing the flow of power in the RR mode. Referring to FIG. 1 together with FIG. 6, in the RR mode, power is received by the power transmission / reception unit 14 from the rear vehicle in a non-contact manner, and the received power is supplied to the power storage unit 16. In the RR mode, the ECU 22 controls the connection unit 20 so as to electrically connect the power transmission / reception unit 14 and the power conversion unit 18, and converts the AC power received from the power transmission / reception unit 14 through the connection unit 20 into direct current. The power conversion unit 18 is controlled so as to be converted and output to the power storage unit 16.

  FIG. 7 is a diagram showing the flow of power in the TR mode. Referring to FIG. 1 together with FIG. 7, in the TR mode, power is supplied from power storage unit 16 to power transmission / reception unit 14, and power is transmitted to rear vehicle by power transmission / reception unit 14 in a contactless manner. In the TR mode, the ECU 22 controls the connection unit 20 so as to electrically connect the power transmission / reception unit 14 and the power conversion unit 18, and converts the power output from the power storage unit 16 into a high-frequency alternating current for connection. The power conversion unit 18 is controlled to be supplied to the power transmission / reception unit 14 via the unit 20.

  FIG. 8 is a diagram showing the flow of power in the TH mode. Referring to FIG. 1 together with FIG. 8, in TH mode, power transmission / reception unit 12 and power transmission / reception unit 14 are electrically connected without passing through power conversion unit 18 and power storage unit 16. In the TH mode, the ECU 22 controls the connection unit 20 to electrically connect the power transmission / reception units 12 and 14 and stops the power conversion unit 18.

  During platooning, any of the plurality of vehicles forming the platooning serves as a master vehicle, and power transmission between the vehicles is planned in the ECU 22 of the master vehicle. Then, the power transmission plan is notified from the master vehicle to the other slave vehicles, and the power conversion unit 18 and the connection unit 20 are controlled by the ECU 22 in each vehicle. This point will be described later.

  FIG. 9 is a diagram illustrating an example of electric power transmission between vehicles during platooning. Referring to FIG. 9, it is assumed that four electric vehicles 10A, 10B, 10C, and 10D are traveling in a platoon. When electric power is transmitted from the first electric vehicle 10A to the last electric vehicle 10D, the electric vehicles 10A, 10B, 10C, and 10D are in a TR mode, a TH mode, a TH mode, and an RF mode, respectively. Thereby, the energy (electric power) stored in the electric vehicle 10A can be transmitted to the electric vehicle 10D via the electric vehicles 10B and 10C in the TH mode.

  FIG. 10 is a diagram illustrating another example of power transmission between vehicles during platooning. Referring to FIG. 10, four electric vehicles 10A, 10B, 10C, and 10D are running in a row, electric power transmission from electric vehicle 10A to electric vehicle 10B, and electric power transmission from electric vehicle 10D to electric vehicle 10C. Are performed simultaneously. In this case, the electric vehicles 10A, 10B, 10C, and 10D are in the TR mode, the RF mode, the RR mode, and the TF mode, respectively. Thereby, the energy (electric power) stored in the electric vehicle 10A can be transmitted to the electric vehicle 10B, and at the same time, the energy (electric power) stored in the electric vehicle 10D can be transmitted to the electric vehicle 10C.

  Referring again to FIG. 1, the communication unit 24 is a communication interface for performing wireless communication with other vehicles forming the row running during the row running. The communication unit 24 exchanges information on each vehicle for performing the platooning and information for performing transmission and transmission between the vehicles during the platooning.

  Next, power transmission between vehicles will be described. Referring to FIG. 1 again, in this electric vehicle 10, the difference between the natural frequency of the power transmission / reception unit 12 and the natural frequency of the power transmission / reception unit (not shown) disposed at the rearmost part of the preceding vehicle is It is ± 10% or less of the natural frequency of the power transmitting / receiving unit 12 or the natural frequency of the power transmitting / receiving unit of the preceding vehicle. Further, the difference between the natural frequency of the power transmission / reception unit 14 and the natural frequency of the power transmission / reception unit (not shown) disposed in the foremost part of the rear vehicle is also determined by the natural frequency of the power transmission / reception unit 14 or the above transmission of the rear vehicle. It is ± 10% or less of the natural frequency of the power receiving unit. By setting the natural frequency of the power transmission / reception units 12 and 14 within such a range, the power transmission efficiency can be increased. On the other hand, when the difference between the natural frequencies is larger than ± 10%, the power transmission efficiency is smaller than 10%, and the power transmission time becomes longer.

  The natural frequency of the power transmission / reception unit 12 (14) means a vibration frequency when the electric circuit (resonance circuit) constituting the power transmission / reception unit 12 (14) freely vibrates. The resonance frequency of the power transmission / reception unit 12 (14) means a natural frequency when the braking force or the electrical resistance is zero in the electric circuit (resonance circuit) constituting the power transmission / reception unit 12 (14).

  A simulation result obtained by analyzing the relationship between the natural frequency difference and the power transmission efficiency will be described with reference to FIGS. 11 and 12. FIG. 11 is a diagram illustrating a simulation model of the power transmission system. FIG. 12 is a diagram illustrating the relationship between the natural frequency shift between the power transmission unit and the power reception unit and the power transmission efficiency.

  Referring to FIG. 11, the power transmission system 89 includes a power transmission device 90 and a power reception device 91. The power transmission device 90 includes an electromagnetic induction coil 92 and a power transmission unit 93. The power transmission unit 93 includes a resonance coil 94 and a capacitor 95 provided in the resonance coil 94. The power receiving device 91 includes a power receiving unit 96 and an electromagnetic induction coil 97. The power receiving unit 96 includes a resonance coil 99 and a capacitor 98 connected to the resonance coil 99.

  The inductance of the resonance coil 94 is defined as an inductance Lt, and the capacitance of the capacitor 95 is defined as a capacitance C1. Further, the inductance of the resonance coil 99 is an inductance Lr, and the capacitance of the capacitor 98 is a capacitance C2. When each parameter is set in this way, the natural frequency f1 of the power transmission unit 93 is represented by the following equation (1), and the natural frequency f2 of the power receiving unit 96 is represented by the following equation (2).

f1 = 1 / {2π (Lt × C1) ^1/2 } (1)
f2 = 1 / {2π (Lr × C2) ^1/2 } (2)
Here, when the inductance Lr and the capacitances C1 and C2 are fixed and only the inductance Lt is changed, the relationship between the deviation of the natural frequency of the power transmission unit 93 and the power reception unit 96 and the power transmission efficiency is shown in FIG. In this simulation, the relative positional relationship between the resonance coil 94 and the resonance coil 99 is fixed, and the frequency of the current supplied to the power transmission unit 93 is constant.

  In the graph shown in FIG. 12, the horizontal axis indicates the deviation (%) of the natural frequency, and the vertical axis indicates the power transmission efficiency (%) at a constant frequency. The deviation (%) in natural frequency is expressed by the following equation (3).

(Deviation of natural frequency) = {(f1−f2) / f2} × 100 (%) (3)
As is clear from FIG. 12, when the deviation (%) in natural frequency is 0%, the power transmission efficiency is close to 100%. When the deviation (%) in natural frequency is ± 5%, the power transmission efficiency is about 40%. When the deviation (%) in natural frequency is ± 10%, the power transmission efficiency is about 10%. When the deviation (%) in natural frequency is ± 15%, the power transmission efficiency is about 5%. That is, by setting the natural frequency of the power transmission unit and the power reception unit so that the absolute value (difference in natural frequency) of the deviation (%) of the natural frequency is within 10% of the natural frequency of the power reception unit 96, It can be seen that the power transmission efficiency can be increased to a practical level. Furthermore, if the natural frequency of the power transmission unit and the power reception unit is set so that the absolute value of the deviation (%) of the natural frequency is 5% or less of the natural frequency of the power reception unit 96, the power transmission efficiency can be further improved, so that preferable. The simulation software employs electromagnetic field analysis software (JMAG (registered trademark): manufactured by JSOL Corporation).

  Referring to FIG. 1 again, power transmission / reception unit 12 is formed between power transmission / reception unit 12 and the power transmission / reception unit of the preceding vehicle, and vibrates at a specific frequency, power transmission / reception unit 12 and the front vehicle. The power is transmitted and received in a non-contact manner with the power transmitting / receiving unit of the vehicle ahead through at least one of the electric field that is formed between the power transmitting / receiving unit and the electric field that vibrates at a specific frequency. The coupling coefficient κ between the power transmitting / receiving unit 12 and the power transmitting / receiving unit of the preceding vehicle is 0.1 or less, and the electric vehicle is made to resonate (resonate) by the electromagnetic field between the power transmitting / receiving unit 12 and the power transmitting / receiving unit of the preceding vehicle. Electric power is transmitted between the ten power transmission / reception units 12 and the power transmission / reception unit disposed at the rearmost part of the preceding vehicle.

  Similarly, the power transmission / reception unit 14 is formed between the power transmission / reception unit 14 and the power transmission / reception unit of the rear vehicle and vibrates at a specific frequency, and the power transmission / reception unit 14 and the power transmission / reception unit of the rear vehicle The power is exchanged in a non-contact manner with the power transmission / reception unit of the rear vehicle through at least one of the electric field that is formed between the two and that vibrates at a specific frequency. The coupling coefficient κ between the power transmission / reception unit 14 and the power transmission / reception unit of the rear vehicle is 0.1 or less, and the power transmission / reception unit 14 and the power transmission / reception unit of the rear vehicle are resonated (resonated) by an electromagnetic field. Electric power is transmitted between the ten power transmission / reception units 14 and the power transmission / reception unit disposed in the foremost part of the rear vehicle.

  As described above, in the electric vehicle 10, the power transmission / reception unit 12 and the power transmission / reception unit of the front vehicle are resonated (resonated) by the electromagnetic field. In non-contact, power is transmitted. Further, power is transmitted in a non-contact manner between the power transmitting / receiving unit 14 and the power transmitting / receiving unit of the rear vehicle by causing the power transmitting / receiving unit 14 and the power transmitting / receiving unit of the rear vehicle to resonate (resonate) with each other. In the power transmission, such a coupling between the power transmitting / receiving unit 12 and the power transmitting / receiving unit of the preceding vehicle (coupling between the power transmitting / receiving unit 14 and the power transmitting / receiving unit of the rear vehicle) is, for example, “magnetic resonance coupling”, “magnetic field ( Magnetic field) resonance coupling ”,“ electromagnetic field (electromagnetic field) resonance coupling ”,“ electric field (electric field) resonance coupling ”, and the like. The “electromagnetic field (electromagnetic field) resonance coupling” means a coupling including any of “magnetic resonance coupling”, “magnetic field (magnetic field) resonance coupling”, and “electric field (electric field) resonance coupling”.

  When the power transmission / reception unit 12 and the power transmission / reception unit of the preceding vehicle are formed by coils as described above, the power transmission / reception unit 12 and the power transmission / reception unit of the front vehicle are mainly coupled by a magnetic field (magnetic field), A “magnetic resonance coupling” or “magnetic field (magnetic field) resonance coupling” is formed. It is also possible to employ, for example, an antenna such as a meander line for the power transmission / reception unit 12 and the power transmission / reception unit of the vehicle ahead. In this case, the power transmission / reception unit 12 and the power transmission / reception unit of the vehicle ahead Are coupled mainly by an electric field (electric field) to form an “electric field (electric field) resonance coupling”. The same applies to the connection between the power transmission / reception unit 14 and the power transmission / reception unit of the rear vehicle.

  FIG. 13 is an equivalent circuit diagram when electric power is transmitted between two adjacent electric vehicles 10A and 10B. In FIG. 13, it is assumed that electric vehicle 10B is traveling following electric vehicle 10A.

  Referring to FIG. 13, power transmission / reception unit 14 provided at the rearmost part of electric vehicle 10 </ b> A includes an electromagnetic induction coil 110, a resonance coil 112, and a capacitor 114. Power transmission / reception unit 12 provided at the forefront of electric vehicle 10 </ b> B includes a resonance coil 116, a capacitor 118, and an electromagnetic induction coil 120.

  In the power transmission / reception unit 14, the resonance coil 112 forms an LC resonance circuit together with the capacitor 114. Also in the power transmission / reception unit 12, the resonance coil 116 forms an LC resonance circuit together with the capacitor 118. The difference between the natural frequency of the LC resonant circuit formed by the resonant coil 112 and the capacitor 114 and the natural frequency of the LC resonant circuit formed by the resonant coil 116 and the capacitor 118 is ± 10% or less of the natural frequency. is there.

  The case where electric power is transmitted from the electric vehicle 10 </ b> A to the electric vehicle 10 </ b> B will be described. In the electric vehicle 10 </ b> A, high-frequency AC power is supplied from the connection unit 20 to the electromagnetic induction coil 110, and the resonance coil 112 is used using the electromagnetic induction coil 110. Is supplied with power. Then, energy (electric power) moves from resonance coil 112 to resonance coil 116 through a magnetic field formed between resonance coil 112 and resonance coil 116 of electric vehicle 10B. The energy (electric power) moved to the resonance coil 116 is taken out using the electromagnetic induction coil 120 and transmitted to the connection part 20 of the electric vehicle 10B.

  The capacitors 114 and 118 are provided to adjust the natural frequency of the resonance circuit. When a desired natural frequency is obtained using the stray capacitance of the resonance coil, the capacitors 114 and 118 are provided. There may be no configuration.

  FIG. 14 is a diagram showing the relationship between the distance from the current source (magnetic current source) and the intensity of the electromagnetic field. Referring to FIG. 14, the electromagnetic field mainly consists of three components. The curve k1 is a component that is inversely proportional to the distance from the wave source, and is referred to as a “radiated electromagnetic field”. A curve k2 is a component inversely proportional to the square of the distance from the wave source, and is referred to as an “induction electromagnetic field”. The curve k3 is a component inversely proportional to the cube of the distance from the wave source, and is referred to as an “electrostatic magnetic field”.

  The “electrostatic magnetic field” is a region where the intensity of the electromagnetic wave suddenly decreases with the distance from the wave source. In the resonance method, the energy (using the near field (evanescent field) where this “electrostatic magnetic field” is dominant is used. Power) is transmitted. That is, in a near field where “electrostatic magnetic field” is dominant, by resonating a pair of resonators having close natural frequencies (for example, a pair of resonance coils), one resonator (primary resonance coil) is resonated with the other. Energy (electric power) is transmitted to the resonator (secondary resonance coil). Since this “electrostatic magnetic field” does not propagate energy far away, the resonance method transmits power with less energy loss than electromagnetic waves that transmit energy (electric power) by “radiant electromagnetic field” that propagates energy far away. be able to.

  15 and 16 are functional block diagrams of the ECU 22 shown in FIG. 15 shows the function of the ECU 22 when the electric vehicle 10 becomes a master vehicle during platooning, and FIG. 16 shows the function of the ECU 22 when the electric vehicle 10 is a slave vehicle during platooning.

  Referring to FIG. 15, ECU 22 includes a communication control unit 50, a convoy travel control unit 51, an energy information acquisition unit 52, an energy plan unit 54, a power conversion control unit 56, and a switching control unit 58. . The communication control unit 50 controls communication by the communication unit 24 (FIG. 1) with other vehicles that form the platooning during the platooning. The convoy travel control unit 51 executes various controls (inter-vehicle distance control, speed control, etc.) for performing convoy travel. Note that the control information for carrying out platooning is always communicated with other vehicles by the communication control unit 50.

  The energy information acquisition unit 52 acquires information regarding the energy of the electric vehicle 10. Specifically, energy information acquisition unit 52 stores the state of charge of power storage unit 16 (FIG. 1) (also referred to as SOC (State Of Charge), for example, expressed as a percentage of the fully charged state of power storage unit 16). Calculation is performed based on the input / output current, voltage, and the like of the unit 16. The SOC of the power storage unit 16 can be calculated by various known methods. Further, the energy information acquisition unit 52 acquires the maximum energy amount of the power storage unit 16, the loss energy per unit travel distance of the electric vehicle 10, and the like. These pieces of information may be acquired using a map or the like based on various parameters (such as temperature and traveling speed), or may be fixed values.

  The energy planning unit 54 receives energy information of the electric vehicle 10 from the energy information acquisition unit 52. Moreover, the energy plan part 54 acquires the energy information of the other vehicle which forms platooning by the communication control part 50. FIG. And the energy plan part 54 plans the electric power transmission between the vehicles which form platooning according to the below-mentioned method. Schematically, the power transmission mode of each vehicle is planned so that power is transmitted from a vehicle having sufficient energy to a vehicle having no energy while considering power transmission efficiency. Then, the power transmission plan is transmitted by the communication control unit 50 to another vehicle that forms the platooning.

  The power conversion control unit 56 controls the power conversion unit 18 (FIG. 1) based on the calculation result of the energy planning unit 54. Specifically, when it is necessary to supply electric power from the electric vehicle 10 to another vehicle, the power conversion control unit 56 converts the electric power output from the power storage unit 16 into a high-frequency alternating current to connect the connection unit 20. A control command for driving the power converter 18 is generated so as to be output to On the other hand, when it is necessary to supply power from other vehicles to power storage unit 16 of electrically powered vehicle 10, power conversion control unit 56 converts AC power received from connection unit 20 into direct current and outputs it to power storage unit 16. As described above, the control command is generated. When electric power only passes through electric vehicle 10 (TH mode), power conversion control unit 56 generates a control command for stopping power conversion unit 18.

  The switching control unit 58 controls the connection unit 20 (FIG. 1) based on the calculation result of the energy planning unit 54. Specifically, when it is necessary to transfer power between the power storage unit 16 of the electric vehicle 10 and the preceding vehicle (RF mode, TF mode), the switching control unit 58 converts the power transmission / reception unit 12 into power conversion. A switching command for electrical connection with the unit 18 is generated. When it is necessary to transfer power between the power storage unit 16 of the electric vehicle 10 and the rear vehicle (RR mode, TR mode), the switching control unit 58 replaces the power transmission / reception unit 14 with the power conversion unit 18. A switching command for electrical connection is generated. When electric power only passes through electric vehicle 10 (TH mode), switching control unit 58 generates a switching command for electrically connecting power transmission / reception unit 12 to power transmission / reception unit 14.

  Next, referring to FIG. 16, when the electric vehicle 10 is a slave vehicle during the platooning, information on the energy of the electric vehicle 10 collected by the energy information acquisition unit 52 is output to the communication control unit 50. And transmitted to the master vehicle using the communication unit 24.

  The power conversion control unit 56 receives the power transmission plan planned in the master vehicle and received by the communication unit 24 (FIG. 1) from the communication control unit 50, and controls the power conversion unit 18 (FIG. 1) according to the plan. To do. Similarly, the switching control unit 58 also receives the power transmission plan planned for the master vehicle from the communication control unit 50, and controls the connection unit 20 (FIG. 1) according to the plan. The other parts are as described in FIG.

  FIG. 17 is a flowchart for explaining the processing procedure of the power transmission plan between the vehicles executed by the ECU 22 during the platooning. The process shown in this flowchart is called from the main routine and executed at regular time intervals or when a predetermined condition is satisfied.

  Referring to FIG. 17, ECU 22 creates the following information, that is, map information including road inclination, departure position, destination position, time limit for arrival at the destination, Information such as the energy of each vehicle forming the platooning, the maximum energy of the power storage unit 16 of each vehicle, the loss per unit travel distance of each vehicle, and the power transmission efficiency is acquired (step S10). Map information, departure position, destination position, time limit information, and the like are acquired from a car navigation device (not shown), for example.

  Next, the ECU 22 creates a power transmission plan between vehicles by dynamic programming based on the above information (step S20). The control target is that the remaining energy of any vehicle does not become zero before reaching the destination, and maximizes the sum of the remaining energy of all vehicles at the destination. The control output is a switching command to the connection unit 20 and a control command to the power conversion unit 18 in each vehicle.

  Here, if there is no solution, that is, if there is a vehicle that cannot reach the destination (YES in step S30), the ECU 22 notifies the user to that effect without performing power transmission (step S50). ). On the other hand, when the destination can be reached (NO in step S30), ECU 22 performs power transmission between the vehicles based on the power transmission plan created in step S20 (step S40).

  As described above, in the first embodiment, electric vehicle 10 includes power transmission / reception units 12 and 14 for exchanging power in a non-contact manner with an adjacent vehicle during platooning. And since the connection part 20 which selectively connects any two of the power transmission / reception parts 12 and 14 and the power conversion part 18 is provided, electric power can be exchanged between the vehicles which run in a row. Thereby, electric power can be transmitted from an electric vehicle with sufficient electric power to an electric vehicle with no margin. Therefore, according to this Embodiment 1, the cruising distance at the time of platooning can be extended.

  In the first embodiment, the difference between the natural frequency of the power transmitting / receiving unit 12 and the natural frequency of the power transmitting / receiving unit disposed at the rearmost part of the preceding vehicle is the natural frequency of the power transmitting / receiving unit 12 or the preceding vehicle. It is ± 10% or less of the natural frequency of the power transmission / reception unit. Further, the difference between the natural frequency of the power transmission / reception unit 14 and the natural frequency of the power transmission / reception unit disposed in the foremost part of the rear vehicle is the natural frequency of the power transmission / reception unit 14 or the natural frequency of the power transmission / reception unit of the rear vehicle. ± 10% or less. Thereby, electric power is transmitted between vehicles by electromagnetic field resonance having a larger power transmission distance than electromagnetic induction. Therefore, according to this Embodiment 1, compared with the case where the electric power transmission method by electromagnetic induction is employ | adopted, electric power can be transmitted between vehicles even if the inter-vehicle distance at the time of platooning becomes large.

  Further, according to the first embodiment, since the power transmission plan is created using the dynamic programming method, it is possible to optimize the power transmission during the platooning.

[Embodiment 2]
In the first embodiment, the dynamic transmission method is used to create a power transmission plan between vehicles during the platooning. In this second embodiment, power transmission is planned and implemented by a simpler method. The

  The overall configuration of the electric vehicle in the second embodiment is the same as that of electric vehicle 10 according to the first embodiment shown in FIG.

  FIG. 18 is a flowchart for illustrating a processing procedure of power transmission between vehicles executed by ECU 22 in the second embodiment. The process shown in this flowchart is also called from the main routine and executed at regular time intervals or when a predetermined condition is satisfied.

  Referring to FIG. 18, ECU 22 performs the following information: map information including road inclination, departure position, destination position, time limit for arrival at destination, energy of each vehicle forming platooning, each vehicle The information such as the maximum energy of the power storage unit 16, the loss per unit travel distance of each vehicle, and the power transmission efficiency is acquired (step S 110). This process is the same as the process executed in step S10 shown in FIG.

  Next, the ECU 22 calculates the current remaining travel distance of each vehicle using the above information (step S120). As a result, when there is a vehicle that cannot reach the destination (YES in step S130), ECU 22 predicts the energy margin of each vehicle when it reaches the destination (step S140). As an example, in each vehicle, an energy margin is predicted based on the estimated SOC value of the power storage unit 16 when the destination is reached.

  Then, the ECU 22 has the shortest remaining travel distance from the nearest vehicle that has sufficient energy when it reaches the destination and has the shortest remaining travel distance in the order of vehicles with the shortest remaining travel distance. Electric power transmission between the vehicles is performed so as to transmit electric power to the vehicles (step S150).

  If it is determined in step S130 that there is no vehicle that cannot reach the destination (NO in step S130), the ECU 22 proceeds to step S160 without executing steps S140 and S150.

  As described above, according to the second embodiment, power transmission between vehicles can be planned and executed by a simpler method for power transmission between vehicles during platooning.

[Embodiment 3]
In the first and second embodiments described above, the energy state of all the vehicles may be displayed on each vehicle forming the row running. Further, based on the display result, the user may be able to manually set power transmission between vehicles.

  FIG. 19 is an overall configuration diagram of an electric vehicle 10E according to the third embodiment. Referring to FIG. 19, this electric vehicle 10 </ b> E further includes a display setting unit 26 in the configuration of electric vehicle 10 shown in FIG. 1.

  Display setting unit 26 obtains the energy state of electric vehicle 10E (for example, the SOC of power storage unit 16) from ECU 22. Moreover, the display setting part 26 acquires the energy state of each vehicle other than the electric vehicle 10E by the communication part 24. Then, the display setting unit 26 displays the acquired energy state of each vehicle (including the electric vehicle 10E).

  Moreover, the display setting part 26 is comprised so that a user can set the energy transmission between vehicles based on the energy display state of each vehicle. When the energy transmission between the vehicles is set by the user, the display setting unit 26 transmits information on the energy transmission between the vehicles to each vehicle by the communication unit 24 and notifies the ECU 22 of the electric vehicle 10E. .

The other configuration of the electric vehicle 10E is the same as that of the electric vehicle 10.
As described above, according to the third embodiment, since the energy state of all vehicles is displayed on the display setting unit 26 for each vehicle forming the platooning, the user must grasp the energy state of each vehicle. Can do. Furthermore, according to the third embodiment, electric power transmission can be performed based on the user's judgment based on the energy state of each vehicle displayed on the display setting unit 26.

  In each of the above embodiments, power is exchanged between vehicles traveling in a row, but power received in a non-contact manner from a power supply facility such as a charging station while the vehicle is stopped is received from the power supply facility. It is also possible to transmit power without contact to a vehicle adjacent to the vehicle.

  In the above description, power transmission / reception units 12 and 14 correspond to one example of “power receiving device” and “power transmitting device” in the present invention, respectively, or one example of “power transmitting device” and “power receiving device”, respectively. . The ECU 22 corresponds to an embodiment of the “control unit” in the present invention. Further, the energy planning unit 54 of the ECU 22 corresponds to an example of the “planning unit” in the present invention, and the process executed by the ECU 22 in step S50 corresponds to the process executed by the “notification unit” in the present invention. To do.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.

  10, 10A to 10E Electric vehicle, 12, 14 Power transmission / reception unit, 16 Power storage unit, 17 Power generation unit, 18 Power conversion unit, 20 Connection unit, 22 ECU, 24 Communication unit, 26 Display setting unit, 30, 32, 34 Switch, 36, 38, 40 terminal, 42 connector section, 44 case, 50 communication control section, 51 convoy travel control section, 52 energy information acquisition section, 54 energy planning section, 56 power conversion control section, 58 switching control section, 110, 120 Electromagnetic induction coil, 112, 116 Resonant coil, 114, 118 Capacitor.

Claims (14)

A power receiving device configured to be able to receive power from the outside of the vehicle without contact;
An electric vehicle comprising: a power transmission device configured to transmit power received by the power reception device to the outside of the vehicle. A rechargeable power storage unit that stores the power received by the power receiving device; and
A power conversion unit connected to the power storage unit and configured to be capable of bi-directional power conversion;
A connection unit that selectively connects any two of the power reception device, the power transmission device, and the power conversion unit;
The electric vehicle according to claim 1, further comprising a control unit that controls the power conversion unit and the connection unit.   3. The control unit according to claim 2, wherein when the power transmission from the power receiving apparatus to the power transmission apparatus is requested, the control unit controls the connection unit to electrically connect the power reception apparatus to the power transmission apparatus. Electric vehicle. The power receiving device is configured to be able to receive power from a first vehicle adjacent to the electric vehicle in a non-contact manner,
4. The electric vehicle according to claim 1, wherein the power transmission device is configured to be able to transmit power to a second vehicle adjacent to the electric vehicle without contact. 5. The power receiving device is configured to be able to receive power from the first vehicle in a non-contact manner during a platooning in which a plurality of vehicles travel while maintaining a predetermined inter-vehicle distance,
5. The electric vehicle according to claim 4, wherein the power transmission device is configured to be able to transmit power to the second vehicle in a non-contact manner during the platooning. 6. The power receiving device is arranged at one of the frontmost part of the vehicle or the rearmost part of the vehicle,
6. The electric vehicle according to claim 4, wherein the power transmission device is arranged at the other of the frontmost part of the vehicle or the rearmost part of the vehicle. The difference between the natural frequency of the power receiving device and the natural frequency of the power transmitting unit configured to transmit power to the power receiving device in the first vehicle is ± 10 of the natural frequency of the power receiving device or the natural frequency of the power transmitting unit. % Or less,
The difference between the natural frequency of the power transmission device and the natural frequency of the power reception unit configured to receive power from the power transmission device in the second vehicle is ± 10 of the natural frequency of the power transmission device or the natural frequency of the power reception unit. The electric vehicle according to any one of claims 4 to 6, wherein the electric vehicle is equal to or less than%.   The electric vehicle according to claim 7, wherein each of a coupling coefficient between the power reception device and the power transmission unit and a coupling coefficient between the power transmission device and the power reception unit is 0.1 or less. The power reception device is formed between the power reception device and the power transmission unit, and is formed between the magnetic field that vibrates at a specific frequency, between the power reception device and the power transmission unit, and at a specific frequency. Receiving power from the power transmission unit through at least one of an oscillating electric field,
The power transmission device is formed between the power transmission device and the power reception unit, and is formed between the magnetic field that vibrates at a specific frequency, between the power transmission device and the power reception unit, and at a specific frequency. The electric vehicle according to claim 7 or 8, wherein power is transmitted to the power receiving unit through at least one of a vibrating electric field. The power receiving device can further transmit power to the outside of the vehicle without contact,
The electric vehicle according to any one of claims 1 to 9, wherein the power transmission device can further receive power from the outside of the vehicle in a non-contact manner. The power receiving device is configured to be capable of receiving power in a non-contact manner from a power supply facility provided outside the vehicle,
The electric power vehicle according to any one of claims 1 to 3, wherein the power transmission device is configured to be able to transmit power to a vehicle adjacent to the electric vehicle without contact. A plurality of vehicles, each of which is an electric vehicle according to any one of claims 1 to 10,
A planning unit that plans power transmission between the plurality of vehicles using dynamic programming;
In each of the plurality of vehicles, the control unit controls the power conversion unit and the connection unit based on a calculation result of the planning unit.   The information processing apparatus according to claim 12, further comprising a notification unit configured to notify a user of the plurality of vehicles when there is a vehicle that cannot reach a destination among the plurality of vehicles as a result of the calculation by the planning unit. Power transmission system. A plurality of vehicles, each of which is an electric vehicle according to any one of claims 1 to 10,
A planning unit that plans power transmission between the plurality of vehicles,
The planning unit calculates a travelable distance of each vehicle when power transmission is not performed between the plurality of vehicles, and when there is a vehicle that cannot reach the destination among the plurality of vehicles, Calculate the energy margin of each vehicle when it reaches, and cannot reach the destination from the nearest vehicle from the vehicle that has sufficient energy when it reaches the destination and cannot reach the destination An electric power transmission system for planning electric power transmission between the plurality of vehicles so as to transmit electric power to the vehicles.

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