JP2011167044A - Electric vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric vehicle which can be charged with a simple configuration. <P>SOLUTION: The electric vehicle 10 includes an energy accumulating device 13, a motor 12 arranged in a wheel 21 of a vehicle wheel 20, a conductor 34 which connects the energy accumulating device and the motor, and a current controller 23. The motor includes a stator 33 which has a stator core 31, and a coil 32 disposed and extended between inner and outer peripheral sides of the stator core, and a rotor 35 configured to rotate by magnetic field generated from the stator. An axial direction of the stator core is aligned in the width direction of the vehicle. The motor is arranged in the wheel, so that a connecting portion 45 of the coil faces to a vehicle outside end surface in the wheel. The current controller executes charging control for transmitting a current flowing through the coil with induced voltage which is generated at the connecting portion of the coil to the energy accumulating device, by rotating field which is generated by confronting an external apparatus 50 to the vehicle outside end surface, and aligned in the axial direction of the stator, while the vehicle is stopping. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electric vehicle.

Conventionally, an electric vehicle using a motor as a drive source is known. In an automobile using this type of motor as a drive source, the motor is generally driven by the electric power stored in the battery. Therefore, when the electric power of the battery is exhausted, the motor cannot be driven, and the automobile is self-propelled. It becomes impossible. In addition, as a method of charging the battery, there are a method of charging using an external charger, a method of charging regenerative power of a motor, and the like.
Here, an in-wheel motor has been developed in which a separate drive motor is provided for each vehicle wheel, and the motor is disposed in the wheel, and a technique for charging using the in-wheel motor is disclosed ( For example, see Patent Document 1).

  In the power supply device for a vehicle of Patent Document 1, a connector that receives power supplied from the outside of the vehicle and charges the power storage device is provided at a wheel portion of the wheel.

JP 2007-68340 A

  However, in patent document 1, in order to charge using an in-wheel motor, the connector for charge is provided. Therefore, the number of parts increases, and it is necessary to change the configuration of the motor in order to provide the connector, resulting in a complicated configuration.

  The present invention has been made in view of the above circumstances, and provides an electric vehicle that can be charged with a simple configuration.

  In order to solve the above problems, the invention described in claim 1 is a power storage device (for example, the battery 13 in the embodiment) provided in the vehicle and a wheel (for example, the wheel 20 in the embodiment) (for example, the wheel 20). The motor (for example, the drive motor 12 in the embodiment) provided in the wheel 21) in the embodiment, and a conductive wire (for example, the conductive wire 34 in the embodiment) that electrically connects the power storage device and the motor, Drive control for controlling the current flowing through the conducting wire to drive the wheel, and regenerative control for transmitting the regenerative current generated when the vehicle is decelerated or downhill to the power storage device are configured to be executable. A current control device (for example, the PCU 23 in the embodiment), and an electric vehicle (for example, the electric vehicle 10 in the embodiment), The motor includes an annular stator core (for example, the stator core 31 in the embodiment) and a coil wound in the radial direction so as to bridge between the inner peripheral side and the outer peripheral side of the stator core (for example, the coil in the embodiment). 32) (for example, the stator 33 in the embodiment), and a rotor (for example, the rotor 35 in the embodiment) configured to be rotatable by a magnetic field generated from the stator. The axial direction is aligned with the width direction of the vehicle, and is arranged in the wheel so that a bridging portion of the coil (for example, the bridging portion 45 in the embodiment) faces the vehicle outer end surface of the wheel, While the vehicle is stopped, the current control device is an external device (for example, the external device 50 in the embodiment). The rotating magnetic field aligned with the axial direction of the stator generated by being arranged opposite to the vehicle outer end face transmits the current flowing in the coil with the induced voltage generated in the bridging portion of the coil to the power storage device. It is characterized by performing charging control.

  The invention described in claim 2 includes non-drive means for the wheel (for example, the brake 46 in the embodiment), and the current control device performs the charge control when the non-drive means is operating. It is characterized by.

  The invention described in claim 3 is characterized in that the wheel is formed of a non-conductive material.

  According to the first aspect of the present invention, since the rotating magnetic field can be applied to the stator without rotating the rotor of the motor, an induced voltage is generated at the coil bridging portion even when the vehicle is stationary. To do. Therefore, a current flows through the coil according to the induced voltage, and charging can be performed by transmitting the current to the power storage device. In other words, non-contact power feeding can be performed using an external device, and this power feeding action is substantially the same as the regenerative power charging operation during traveling, so that the secondary coil or connector is charged on the vehicle side. It is not necessary to install additional parts. As a result, charging can be performed with a simple configuration.

  According to the invention described in claim 2, by operating the non-driving means, it is possible to reliably prevent the stopped vehicle from moving due to the regenerative torque generated during charging.

  According to the third aspect of the present invention, no current flows through the wheel during charging, and magnetic flux can pass therethrough, so that it is possible to prevent the wheel from generating heat during charging. In addition, since it is possible to prevent loss due to eddy current flowing through the wheel, charging efficiency can be improved.

1 is a schematic side view of an electric vehicle according to an embodiment of the present invention. 1 is a schematic front view of an electric vehicle according to an embodiment of the present invention. It is a front view of the drive motor in the embodiment of the present invention. It is sectional drawing which follows the AA line of FIG. It is sectional drawing which follows the BB line of FIG. It is a schematic structure side view (partial sectional view) of an external device in an embodiment of the present invention. FIG. 7 is a front view of FIG. 6. It is a flowchart explaining the charge method to the battery in embodiment of this invention. It is a schematic structure front view which shows the state in charge in embodiment of this invention. It is a schematic structure side view (partial sectional view) showing another aspect of the external device in the embodiment of the present invention. It is a front view of FIG. It is the elements on larger scale which show the state during charge when the external apparatus of FIG. 10 is used.

  Next, an embodiment of the present invention will be described with reference to FIGS. In the present embodiment, an electric vehicle will be described as an electric vehicle.

(Electric car)
FIG. 1 is a schematic configuration diagram of an electric vehicle. As shown in FIG. 1, an electric vehicle 10 includes a drive motor 12, a battery 13 disposed on the lower floor of the vehicle to supply electric power to the drive motor 12, and a control unit that controls traveling of the electric vehicle 10. 14.

  The electric vehicle 10 configured as described above can normally run by supplying power to the drive motor 12 while the battery 13 is charged with power. However, when the remaining amount of the battery 13 runs out, the electric vehicle 10 cannot run on its own. Therefore, it is necessary to always charge the battery 13 with electric power.

  Here, as shown in FIG. 2, the drive motor 12 mounted on the electric vehicle 10 is composed of an in-wheel motor housed in the wheel 21 of the wheel 20. The wheel 20 includes a wheel 21 formed of a non-conductive substance such as SUS or a resin material, and a tire 22 disposed so as to cover the periphery of the wheel 21. For example, the drive motor 12 is provided on each front wheel of the electric vehicle 10. The drive motor 12 is connected to the battery 13 via a PCU (current control device) 23. Then, in response to an instruction from the PCU 23, the drive motor 12 can be driven by supplying power from the battery 13 to the drive motor 12, or regenerative power generated from the drive motor 12 can be charged to the battery 13. It is configured. A brake 46 that restricts the rotation of the drive shaft 25 is provided inside the wheel 21.

Next, the configuration of the drive motor 12 will be described.
As shown in FIG. 3, the drive motor 12 is wound in a radial direction so as to span between a stator core 31 on which a magnetic plate material having an annular shape when viewed from the front is laminated, and an inner peripheral side and an outer peripheral side of the stator core 31. And a rotor 35 configured to be rotatable by a magnetic field generated from the stator 33.

  As shown in FIGS. 3 and 5, a plurality (12 in this embodiment) of teeth 36 are formed on the stator core 31 such that the teeth 36 protrude radially inward and outward at substantially equal intervals in the front view. Has been. Two coils 32 are arranged in a slot 37 formed between adjacent teeth 36. Two coils 32 arranged in one slot 37 are arranged such that coils 32 having different winding directions are spaced apart from each other. That is, the drive motor 12 of this embodiment is a drive motor 12 having a so-called toroidal winding. A conductive wire 34 is connected to the coil 32. The conducting wire 34 is connected to the battery 13 via the PCU 23.

  As shown in FIG. 4, the rotor 35 includes a housing 38 connected to the drive shaft 25 of the wheel 20, and a permanent magnet 39 arranged to face the stator 33. The rotor 35 of the present embodiment includes an inner peripheral housing 41 disposed so as to face the inner peripheral surface of the stator 33 in a front view, and an outer peripheral side housing 42 disposed so as to face the outer peripheral surface of the stator 33. The inner peripheral side housing 41 is provided with an inner peripheral side permanent magnet 39A facing the inner peripheral surface of the stator 33, and the outer peripheral side housing 42 is provided with an outer peripheral side permanent magnet 39B on the outer peripheral surface of the stator 33. It is provided so as to face each other. Further, the inner peripheral housing 41 and the outer peripheral housing 42 are connected by a connecting portion 43 and integrated as a housing. The connecting portion 43 is formed in an inner portion in the vehicle width direction, and the outer side in the vehicle width direction of the housing 38 is open.

  The inner peripheral side permanent magnet 39A and the outer peripheral side permanent magnet 39B are arranged with a plurality of permanent magnets (eight in this embodiment) alternately arranged along the circumferential direction with different magnetic poles (N pole, S pole). ing. That is, the rotor 35 of the present embodiment is a so-called double rotor structure rotor.

  The drive motor 12 aligns the axial direction of the stator 33 (stator core 31) with the vehicle width direction of the electric vehicle 10 (the axial direction of the drive shaft 25), and the coil 32 on the vehicle outer end face in the wheel 21 of the wheel 20. It is arranged so that the crossover 45 faces (see FIG. 2).

  In the drive motor 12 configured as described above, when the rotor 35 is rotated by the magnetic field generated from the stator 33, the drive shaft 25 connected to the rotor 35 is rotated, and accordingly, the wheel 20 is rotated to rotate the electric vehicle. It is comprised so that 10 can be moved forward / backward.

Next, a method for charging the battery 13 with electric power will be described.
When charging the battery 13 with electric power, an external device 50 is used as shown in FIG. The external device 50 is disposed along the circumferential direction on the surface of the motor 51, the rotating shaft 52 coupled to the motor 51, the disk member 53 disposed at the tip of the rotating shaft 52, and the surface of the disk member 53. A plurality of permanent magnets 54. That is, the external device 50 has a so-called axial gap type rotor. The rotating shaft 52 is configured to be extendable and contractable in the axial direction.

  As shown in FIG. 7, in the permanent magnet 54, a plurality (eight in this embodiment) of permanent magnets each having a different magnetic pole (N pole, S pole) are arranged along the circumferential direction. . Further, the permanent magnet 54 has an annular shape in a state in which the plurality of permanent magnets 54 are attached to the disk member 53, and the permanent magnet 54 and the stator core 31 have an annular shape having substantially the same shape when viewed from the front. ing. By comprising in this way, magnetic flux leakage can be reduced, and a magnetic flux can be efficiently linked with the minimum magnitude | size, and charging efficiency can be improved. Furthermore, the induced voltage can be generated efficiently by making the number of poles of the permanent magnet 39 of the drive motor 12 the same as the number of poles of the permanent magnet 54 of the external device 50 as in this embodiment. .

Next, a method for charging the battery 13 will be described with reference to a flowchart.
As shown in FIG. 8, as a flow on the electric vehicle 10 side, it is determined in step S11 whether or not the vehicle is in a stopped state. If the vehicle is in a stopped state, the process proceeds to step S12. If the vehicle is not in a stopped state, the process ends.

  In step S12, it is determined whether or not the external device 50 is set at a predetermined position. If the external device 50 is set, the process proceeds to step S13, and if not set, step S12 is repeated. In order to charge the battery 13 using the external device 50, the external device 50 is disposed in the immediate vicinity of the drive motor 12, as shown in FIG. Specifically, it arrange | positions so that the permanent magnet 54 of the external apparatus 50 may oppose the surface 21a of the wheel 21. FIG. At this time, the installation position of the external device 50 is adjusted so that the permanent magnet 54 and the stator core 31 face each other.

  In step S13, it is determined whether or not the vehicle brake 46 is applied. If the brake 46 is applied, the process proceeds to step S14. If the brake 46 is not applied, step S13 is repeated. At this time, by operating the brake 46, it is possible to more reliably prevent the drive shaft 25 from rotating and the electric vehicle 10 from moving during charging.

  In step S14, it is determined that the PCU 23 may start charging the battery 13, and the process proceeds to step S15.

  In step S15, it is determined whether or not the external device 50 is driven to start charging the battery. If charging is started, the process proceeds to step S16, and if charging is not started, step S15 is repeated. Specifically, in a state where the position of the external device 50 is fixed, the motor 51 is driven to rotate the permanent magnet 54 around the rotation shaft 52. Then, an interlinkage magnetic flux is generated from the permanent magnet 54 toward the coil 32. Thus, an induced voltage is generated in the crossing portion 45 of the coil 32 by generating a magnetic flux along the axial direction. This induced voltage is configured to charge the battery 13 based on the control of the PCU 23. That is, the battery 13 can be charged with electric power without rotating the wheel 20.

  The induced voltage V generated in the coil 32 of the drive motor 12 is expressed by the following equation.

  Here, P is the number of poles, N is the number of turns of the coil, φ is a 1-pole coil linkage magnetic flux, and t is time. From the above equation (1), it can be seen that even if the number of flux linkages is small, a high induced voltage V can be obtained if the change time is short (if the frequency is high).

  In step S16, charging control is performed to adjust the power (current) supplied to the battery 13 by the PCU 23. When the charging of the battery 13 is completed, the process ends.

  On the other hand, as a flow on the external device 50 side, it is determined whether or not the external device 50 has detected the electric vehicle 10 in step S21. If the electric vehicle 10 is detected, the process proceeds to step S22, and if the vehicle is not detected, the process ends.

  In step S22, it is determined whether or not the external device 50 is set at a predetermined position. If it is set at a predetermined position, the process proceeds to step S23. If it is not set, step S22 is repeated.

  In step S23, it is determined whether or not a charging permission signal from the electric vehicle 10 side is input. If the charge permission signal is input, the process proceeds to step S24, and if not input, step S23 is repeated.

  In step S24, the external device 50 is driven to charge the battery 13. When charging is complete, the process ends.

  According to the present embodiment, since the rotating magnetic field can be applied to the stator 33 without rotating the rotor 35 of the drive motor 12, even if the vehicle (electric vehicle 10) is stationary, the transition portion of the coil 32 An induced voltage is generated at 45. Therefore, a current flows through the coil 32 according to the induced voltage, and charging can be performed by transmitting the current to the battery 13. In other words, contactless power feeding can be performed using the external device 50, and this power feeding action is substantially the same as the regenerative power charging operation during traveling. Installation of auxiliary parts for charging is not required. As a result, charging can be performed with a simple configuration.

  Further, by operating the brake 46 during charging, it is possible to reliably prevent the stopped vehicle from moving due to the regenerative torque generated during charging.

  Furthermore, since the wheel 21 is formed of a non-conductive material, no current flows through the wheel 21 during charging, and the magnetic flux can pass therethrough. Therefore, it is possible to prevent the wheel 21 from generating heat during charging. Moreover, since it can prevent that an eddy current flows into the wheel 21 and a loss arises, charging efficiency can be improved.

  The present invention is not limited to the above-described embodiment, and includes various modifications made to the above-described embodiment without departing from the spirit of the present invention. That is, the specific structure and shape described in the embodiment are merely examples, and can be changed as appropriate.

  For example, in the present embodiment, the case where the external device 50 that generates the magnetic flux by rotating the permanent magnet 54 with the motor 51 has been described. However, as illustrated in FIGS. As the AC power supply 151, the shaft portion 152 connected to the AC power supply device 151, the disk member 153 disposed at the tip of the shaft portion 152, the surface of the disk member 153 is substantially equal along the circumferential direction. A core 154 formed at intervals, and a coil 155 wound so as to cover the periphery of the core 154 are provided. The AC power supply device 151 is connected so that a current can flow through the coil 155. The shaft portion 152 is configured to be extendable and contractable in the axial direction. As shown in FIG. 12, the external device 150 configured as described above is used so that the core 154 faces the stator 33 (stator core 31), and an alternating current is applied to the coil 155 from the alternating current power supply device 151. As a result, a rotating magnetic field can be generated, and substantially the same operational effects as in the above embodiment can be obtained. Further, the magnitude of the flux linkage can be controlled by the magnitude of the alternating current, and the induced voltage of the drive motor 12 can be controlled other than the frequency of the rotating magnetic field.

  In the present embodiment, it is configured to check whether or not the brake 46 is applied. However, the operation of the brake 46 may not be checked. Further, instead of checking the operation of the brake 46, it may be configured to check whether or not the side brake is applied, or may be configured to check whether or not the shift lever is parked. .

  In the present embodiment, an electric vehicle (four-wheeled vehicle) has been described as an electric vehicle. However, the present invention can also be applied to an electric motorcycle or an electric cart.

  DESCRIPTION OF SYMBOLS 10 ... Electric vehicle (electric vehicle) 12 ... Drive motor (motor) 13 ... Battery 20 ... Wheel 21 ... Wheel 23 ... PCU (current control device) 31 ... Stator core 32 ... Coil 33 ... Stator 34 ... Conductor 35 ... Rotor 45 ... Crossing Part (crossover part) 46 ... Brake (non-driving means) 50 ... External equipment

Claims (3)

A power storage device provided in the vehicle;
A motor provided in the wheel of the wheel;
A conducting wire electrically connecting the power storage device and the motor;
Drive control for controlling the current flowing through the conducting wire to drive the wheel, and regenerative control for transmitting the regenerative current generated when the vehicle is decelerated or downhill to the power storage device are configured to be executable. An electric vehicle equipped with a current control device,
The motor is
A stator having an annular stator core, and a coil wound in a radial direction so as to bridge between the inner peripheral side and the outer peripheral side of the stator core;
A rotor configured to be rotatable by a magnetic field generated from the stator, and
With the axial direction of the stator core aligned with the width direction of the vehicle, the stator core is arranged in the wheel so that the bridging portion of the coil faces the vehicle outer end surface of the wheel,
The current controller is
While the vehicle is stopped, the coil is accompanied by an induced voltage generated in a bridging portion of the coil by a rotating magnetic field aligned with the axial direction of the stator generated by arranging an external device to face the outer end surface of the vehicle. An electric vehicle that performs charge control for transmitting a current flowing through the power storage device to the power storage device. Comprising non-drive means for the wheel,
The electric vehicle according to claim 1, wherein the current control device performs the charge control when the non-driving unit is operating.   The electric vehicle according to claim 1, wherein the wheel is made of a nonconductive material.

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