JP2012161235A - Vehicle communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle communication system that ensures preferred wireless communication, even when a battery is being charged.SOLUTION: The vehicle communication system operates an on-board device through wireless communication with an electronic key 20 which is triggered by an operation of a door handle switch 19 arranged in a vehicle 10 with a battery unit 13 made chargeable by being connected to an external power supply 2 via a charging cable 5. The vehicle communication system includes a vehicle-side controller 11 which reduces the charging current amount for the battery unit 13 so long as it is detected in the vehicle 10 that the door handle switch 19 is operated when the vehicle 10 is being charged.

Description

  The present invention relates to a vehicle communication system.

  In recent years, improvements in user convenience have been demanded in vehicles such as four-wheeled vehicles. For this reason, the vehicle authenticates the ID code of the portable device through wireless communication with the portable device (electronic key), and locks and unlocks the vehicle door and drives the engine and motor on the condition that the authentication is established. There is a communication system that allows the start of the source. Examples of the communication system include a smart communication system that automatically performs verification when the electronic key disclosed in Patent Document 1 approaches the vehicle, a wireless communication system that remotely operates the vehicle by a button operation on the electronic key, and the like. is there.

  In recent years, electric cars and hybrid cars that can be driven by electric power have attracted attention. These vehicles include a battery for traveling. And electric power is supplied to the battery for driving | running | working via a charging cable from external power supplies, such as a charging stand provided outside the vehicle. For example, as disclosed in Patent Document 2, one end of the charging cable is connected to the main body of the charging stand, and a power supply plug is provided at the other end. By connecting the power supply plug to an inlet (charging port) provided on the outer side surface of the vehicle, the charging stand and the vehicle are in a conductive state. In this state, the battery for traveling can be charged from the main body of the charging stand via the charging cable.

JP 2008-231734 A JP-A-9-161898

  In general, it is known that a magnetic field is disturbed around a conductive wire in an energized state. When various radio signals are affected by the disturbance of the magnetic field, noise is generated in the radio signals, and there is a possibility that various communications cannot be performed suitably. In addition, the battery for traveling in an electric vehicle or the like is often charged with a large current. Therefore, the disturbance of the magnetic field generated around the charging cable is large and the range is wide. For this reason, there is a possibility that wireless communication performed between the portable device and the vehicle is not suitably performed due to the influence of the disturbance of the magnetic field.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a vehicle communication system that enables suitable wireless communication even during charging of a battery.

  In order to solve the above problems, the invention according to claim 1 is a wireless communication performed with an electronic key triggered by an operation of a switch provided in a vehicle including a battery that can be charged from an external power source. In the vehicle communication system that operates the in-vehicle device using the vehicle, the vehicle reduces the amount of charging current to the battery when it is detected that the switch is operated during charging of the battery, or The gist is to provide control means for zeroing.

  It is well known that a magnetic field disturbance occurs around a charging cable through which a current flows, and that the magnetic field disturbance hinders wireless communication. In this regard, according to the configuration, when wireless communication is performed between the vehicle and the electronic key, the disturbance of the magnetic field that hinders wireless communication is suppressed by reducing the amount of charging current to the battery. The Therefore, wireless communication between the vehicle and the electronic key is preferably executed.

  The gist of a second aspect of the present invention is the vehicle communication system according to the first aspect, wherein the control means recovers a charging current amount to the vehicle after the in-vehicle device is activated.

  According to this configuration, the amount of charging current to the vehicle is recovered without any special operation by the user. That is, the amount of charging current is reduced only when wireless communication between the vehicle and the electronic key is performed.

  According to a third aspect of the present invention, in the vehicular communication system according to the first or second aspect, when the wireless communication is not established, the control unit tries again the wireless communication with the electronic key, If the wireless communication is still not established, the gist is to restore the charging current amount to the vehicle.

  According to this configuration, when a predetermined number of times or a predetermined time elapses due to failure of ID verification, the amount of charging current to the vehicle is recovered. Therefore, even if the in-vehicle device does not operate, the charging time loss associated with the wireless communication is reduced.

  According to a fourth aspect of the present invention, in the vehicle communication system according to any one of the first to third aspects, the switch is provided on a door handle of the vehicle, and the in-vehicle device is The gist of the invention is a door lock device for locking and unlocking the door of the vehicle.

According to this configuration, wireless communication between the vehicle and the electronic key when the vehicle door is locked and unlocked is preferably executed.
According to a fifth aspect of the present invention, in the vehicle communication system according to any one of the first to fourth aspects, the battery is charged by connecting the vehicle and the external power source through a charging cable. The gist is that

  According to this configuration, when charging the battery, the vehicle is directly connected to the external power source. For this reason, the electric power of the stable electric potential is sent to a vehicle from an external power supply. Therefore, the vehicle can easily adjust the amount of charging current sent to the battery.

  The invention according to claim 6 is the vehicle communication system according to any one of claims 1 to 4, wherein a power transmission request signal indicating that power transmission is requested from a parked vehicle is received. A power transmission unit having a power transmission coil that converts electric power from the external power source into a magnetic field, and a power reception coil that is provided in the vehicle and converts a magnetic flux radiated from the power transmission coil into a current used for charging the battery The control means continuously transmits the power transmission request signal during parking, and stops transmitting the power transmission request signal when it is detected that the switch is operated. To do.

  In such a vehicle using so-called non-contact charging, a large magnetic field is generated around the vehicle. For this reason, wireless communication between the electronic key and the vehicle tends to be hindered. In this regard, according to the same configuration, when wireless communication is performed between the electronic key and the vehicle, the vehicle does not transmit a signal indicating that charging is requested. Thereby, since a power transmission coil stops transmission of a magnetic field, generation | occurrence | production of the magnetic field in the periphery of a vehicle is suppressed. Therefore, wireless communication between the electronic key and the vehicle can be suitably performed.

  In the present invention, it is possible to provide a vehicle communication system that enables suitable wireless communication even during charging of a battery.

The block diagram which shows schematic structure of the communication system of this embodiment. The flowchart which shows the control aspect of this embodiment. The block diagram which shows schematic structure of the communication system in another example of this embodiment.

Hereinafter, an embodiment in which the present invention is embodied in a vehicle communication system for an electric vehicle will be described.
As shown in FIG. 1, a vehicle 10 that is an electric vehicle can be charged by a charging device 30 provided in a parking lot or the like. The vehicle 10 is also equipped with a vehicle communication system that enables locking and unlocking of the vehicle door through communication with the electronic key 20 carried by the user.

(Vehicle 10)
As shown in FIG. 1, the vehicle 10 includes a battery unit 13 and a motor 14 as a vehicle device that consumes and drives electric power stored in the battery unit 13. Drive wheels are connected to the output shaft of the motor 14. The battery unit 13 is connected to a charging circuit 12 that converts AC power into DC power. A charging port 10 a is connected to the charging circuit 12. The electric power supplied from the charging device 30 to the vehicle 10 through the charging port 10 a is charged into the battery unit 13 through the charging circuit 12. The charging circuit 12 is connected to a vehicle-side control unit 11 as control means mounted on the vehicle 10 together with the battery unit 13.

  The vehicle-side control unit 11 performs control related to the charging power to the battery unit 13 through the charging circuit 12. Further, the vehicle-side control unit 11 controls power supply to the motor 14 through the battery unit 13. By supplying electric power to the motor 14, the drive wheels are driven via the output shaft of the motor 14. As a result, the vehicle 10 can travel. Further, the battery unit 13 includes a voltage sensor 13 a, and the detection result of the voltage sensor 13 a is output to the vehicle-side control unit 11. The vehicle-side control unit 11 recognizes the charged amount of the battery unit 13 based on the detection result of the voltage sensor 13a.

  In addition, the vehicle 10 is equipped with a vehicle communication key system that enables locking and unlocking of the vehicle door through communication with the electronic key 20 carried by the user. The vehicle door is provided with a door lock device 16 that performs locking and unlocking, and a door handle switch 19 that can be operated from the outside. The door lock device 16 and the door handle switch 19 are connected to the vehicle-side control unit 11. The vehicle side control unit 11 includes a nonvolatile memory 11a. The memory 11a stores a key ID code, a vehicle ID code, and the like that are individually set for the vehicle 10. The vehicle-side control unit 11 performs wireless communication including an ID code with the electronic key 20 by using the operation of the door handle switch 19 as a trigger. When the ID code authentication is established, the vehicle-side control unit 11 locks and unlocks the vehicle door through the door lock device 16. I do.

  A reception circuit 17 and a transmission circuit 18 are connected to the vehicle side control unit 11. The receiving circuit 17 is connected to a receiving antenna 17 a that receives a radio signal from the electronic key 20, and the transmitting circuit 18 is connected to a transmitting antenna 18 a that transmits a radio signal to the electronic key 20.

  When the door handle switch 19 is operated, the vehicle-side control unit 11 generates a request signal for requesting an ID code to the electronic key 20 and inputs the request signal to the transmission circuit 18. The transmission circuit 18 modulates the request signal into a radio wave having a predetermined frequency. In the present embodiment, the predetermined frequency is a frequency in an LF (Low Frequency) band. The transmission antenna 18a transmits the request signal modulated by the transmission circuit 18 around the vehicle. The receiving circuit 17 that has received the response signal including the ID code from the electronic key 20 via the receiving antenna 17a demodulates the response signal and inputs it to the vehicle-side control unit 11. The vehicle-side control unit 11 collates the ID code from the electronic key 20 with the ID code stored in its own memory 11a. When this ID verification is established, the vehicle-side control unit 11 locks and unlocks the vehicle door through the door lock device 16.

  The vehicle-side control unit 11 includes a counter 11b that counts the number of transmissions T of a request signal transmitted to the electronic key 20. The counter 11b is reset every time the door handle switch 19 is operated.

(Electronic key 20)
The electronic key 20 includes a key side control unit 21 and a receiving circuit 27 and a transmitting circuit 28 connected thereto. The receiving circuit 27 is connected to a receiving antenna 27 a that receives a radio signal from the vehicle 10, and the transmitting circuit 28 is connected to a transmitting antenna 28 a that transmits a radio signal to the vehicle 10. The key-side control unit 21 includes a nonvolatile memory 21a, and a key ID code, a vehicle ID code, and the like are stored in the memory 21a as in the memory 11a of the vehicle 10.

  The receiving circuit 27 that has received the request signal from the vehicle 10 via the receiving antenna 27 a demodulates the request signal and inputs it to the key-side control unit 21. Receiving the request signal, the key-side control unit 21 generates a response signal including the ID code stored in its own memory 21 a and inputs the response signal to the transmission circuit 28. The transmission circuit 28 modulates this response signal into a radio wave having a predetermined frequency and transmits the response signal to the periphery of the vehicle via the transmission antenna 18a. In the present embodiment, the predetermined frequency is a frequency in a UHF (Ultra High Frequency) band.

(Charging device 30)
The charging device 30 includes a charging cable 5 connected to an external power source 2 that is a commercial power source. A power supply plug 36 is provided at the end of the charging cable 5. The power plug 36 can be inserted into the charging port 10a. The power supply plug 36 is provided with a changeover switch 36a that can be operated from the outside. In addition, the charging cable 5 is provided with a switch element 39 that switches between supply and interruption of power to the vehicle 10. The charging cable 5 is provided with a signal line for connecting the changeover switch 36a and the switch element 39 in addition to a power line for transmitting AC power. The user can turn on and off the switch element 39 by operating the changeover switch 36a. In addition, the power line and the signal line which comprise the charging cable 5 are bundled, and the outer periphery is coat | covered with resin which consists of nonelectroconductive materials. In FIG. 1, only the power line is shown as a charging cable 5 by a solid line, and the signal line is not shown.

Next, a manner of charging the vehicle 10 will be described.
When the power supply plug 36 is inserted into the charging port 10a, the vehicle 10 and the charging device 30 are in a conductive state. When the changeover switch 36a is turned on and the switch element 39 is turned on in this conductive state, charging from the charging device 30 to the vehicle 10 is started.

  AC power from the external power source 2 is input to the charging circuit 12 via the charging cable 5. The charging circuit 12 converts the input AC power into DC power and supplies it to the battery unit 13. In this way, the battery unit 13 is charged. Note that the amount of power stored in the battery unit 13 is constantly monitored by the vehicle-side control unit 11. The vehicle-side control unit 11 controls the conversion from AC power to DC power in the charging circuit 12 according to the amount of power stored in the battery unit 13. Therefore, when the battery unit 13 is fully charged, the vehicle-side control unit 11 stops charging the battery unit 13. The stop of charging means that the amount of charging current to the battery unit 13 becomes 0 (zero).

Next, a case where wireless communication is performed between the vehicle 10 and the electronic key 20 while the vehicle 10 is being charged will be described with reference to a flowchart shown in FIG.
As shown in FIG. 2, when the vehicle-side control unit 11 recognizes that the door handle switch 19 is operated while the vehicle 10 is being charged, the vehicle-side control unit 11 stops charging the battery unit 13. (Step S1). At this time, the counter 11b is reset. And the vehicle side control part 11 produces | generates a request signal, transmits the request signal to the electronic key 20 through the transmission circuit 18 (step S2), and increases the frequency | count T of transmission by 1 (step S3).

  Thereafter, the vehicle-side control unit 11 attempts to receive a response signal from the electronic key 20 for a predetermined time (for example, 1 second) (step S4). If YES in step S4, that is, if a response signal from the electronic key 20 has been received, it is determined whether or not the ID code included in the response signal is collated with the ID code stored in the memory 11a. Judgment is made (step S5). If YES in step S 5, that is, if the ID code of the electronic key 20 and the ID code of the memory 11 a of the vehicle (vehicle 10) are verified, the vehicle-side control unit 11 applies the vehicle door through the door lock device 16. A lock operation is performed (step S6). And the vehicle side control part 11 restarts the charge to the battery unit 13 (step S7), and complete | finishes a series of control processes.

  If NO in step S4, that is, if a response signal from the electronic key 20 cannot be received, and NO in step S5, that is, collation between the ID code of the electronic key 20 and the ID code of the memory 11a of itself (vehicle 10) is established. If not, it is determined whether or not the number of transmissions T is equal to or less than a predetermined number 3 (step S8). If YES in step S8, that is, if the number of transmissions T is 3 or less, the process proceeds to step S2 again. If NO in step S8, that is, if the number of transmissions T is not 3 or less, the process proceeds to step S7. Therefore, in this case, the vehicle door is not locked or unlocked through the door lock device 16.

  When the user holding the electronic key 20 operates the door handle switch 19, the vehicle-side control unit 11 can usually receive a response signal by transmitting a request signal once. That is, when the request signal is transmitted three times and the response signal cannot be received, or when the ID verification becomes illegal, it is assumed that the third person is operating the door handle switch 19 unnecessarily. In this example, the unauthorized unlocking of the vehicle door by such a third party is also suppressed.

  As described in the above problem, it is known that a disturbance of the magnetic field occurs around the charging cable 5 during charging. The disturbance of the magnetic field also affects the radio signal between the communication objects, and hinders suitable communication. Therefore, in this example, when wireless communication is performed between the vehicle 10 and the electronic key 20, charging of the vehicle 10 is temporarily stopped with an operation of the door handle switch 19 as a trigger. Thereby, the disturbance of the magnetic field based on charge is eliminated, and wireless communication between the vehicle 10 and the electronic key 20 is suitably performed.

As described above in detail, according to the present embodiment, the following effects can be obtained.
(1) When the door handle switch 19 is operated during charging of the battery unit 13, the vehicle-side control unit 11 stops charging the battery unit 13. Thereby, the disturbance of the magnetic field around the charging cable 5 is suppressed. Therefore, wireless communication between the vehicle 10 and the electronic key 20 is suitably executed.

  (2) The vehicle-side control unit 11 resumes charging the battery unit 13 after the ID verification is established and the vehicle door is locked and unlocked via the door lock device 16. That is, charging of the vehicle is resumed without any special operation by the user.

  (3) The vehicle-side control unit 11 resumes charging the battery unit 13 without executing locking / unlocking of the vehicle door when the ID verification is not established even if the request signal is transmitted three times, which is a predetermined number of times. Let Thereby, the loss of the charging time accompanying wireless communication can be reduced.

In addition, you may change the said embodiment as follows.
-In above-mentioned embodiment, although charging to the battery unit 13 was restarted after execution of locking / unlocking of a vehicle door, it is not necessary to restart. Even in this case, the wireless communication between the vehicle 10 and the electronic key 20 is preferably executed without receiving a disturbance of the magnetic field due to the charging.

  In the above embodiment, the number of transmissions of the request signal transmitted from the vehicle 10 is set to 3 times, but this number may be set to an arbitrary number. In addition, in order to reduce the loss of charging time, it is better that this number is smaller. Specifically, a one-digit number is desirable. Further, the request signal may be transmitted for a predetermined time that is arbitrarily set. Even in this case, in order to reduce the loss of the charging time, it is preferable that the predetermined time is short. Specifically, it is preferably within one digit second.

  In the above embodiment, the vehicle side control unit 11 may perform RSSI (Reception Signal Strength) determination. In this case, a reception signal strength determination unit is provided in the vehicle side control unit 11. Explaining using the flowchart shown in FIG. 2, for example, in step S4, it is determined whether or not the strength of the received signal is greater than or equal to a predetermined value after receiving the response signal. If the received signal strength is greater than or equal to the predetermined value, the process proceeds to step S5. If the received signal strength is less than the predetermined value, the process proceeds to step S8. If it does in this way, it can control that a 3rd party relays a radio signal and improperly locks and unlocks a vehicle door, for example.

  -In above-mentioned embodiment, in order to perform ID collation when performing locking / unlocking of a vehicle door, the vehicle side control part 11 stopped charging by having operated the door handle switch 19 as a trigger. However, the stop of charging is not limited to locking / unlocking the vehicle door, and may be performed, for example, when locking / unlocking a trunk or the like. In this case, the vehicle-side control unit 11 may stop charging not only by the door handle switch 19 but also by an operation of a switch provided in the trunk.

  In the above embodiment, the vehicle-side control unit 11 stops charging from the external power source 2 through the charging circuit 12 when performing wireless communication with the electronic key 20, but reduces the amount of charging current. May be. By doing so, the range in which the magnetic field disturbance due to charging occurs and the intensity of the disturbance are also reduced, so that wireless communication between the vehicle 10 and the electronic key 20 is suitably executed.

  -The door handle switch 19 of the said embodiment may be a touch sensor. In this case, it is necessary to always activate the touch sensor even during charging. Even if it is such a structure, the effect similar to the said embodiment can be acquired.

  In the above embodiment, the vehicle-side control unit 11 stops charging while it is determined that locking / unlocking of the vehicle door is executed after the door handle switch 19 is operated or ID verification is not established. However, the disturbance of the magnetic field generated during charging has a large effect on the radio wave in the LF band, but the influence on the radio wave in the UHF band is small, so the vehicle-side control unit 11 stops charging only when transmitting a request signal. You may let them. That is, when the request signal is transmitted, charging of the vehicle 10 may be resumed. Even in this case, the wireless communication between the vehicle 10 and the electronic key 20 is preferably executed.

  In the above-described embodiment, the case where the vehicle communication system is applied to an electric vehicle has been described. However, the present invention can be applied to any vehicle that charges a battery from an external power source. For example, there are plug-in hybrid vehicles, electric motorcycles, and the like.

  In the above embodiment, charging to the battery unit 13 is performed via the charging cable 5 that connects the vehicle 10 and the external power source 2, but even so-called non-contact charging that does not involve the charging cable 5. Good.

  For example, as shown in FIG. 3, a power receiving coil 41 connected to the charging circuit 12 is provided in the lower part of the vehicle 10. The power receiving coil 41 converts the magnetic field into a current and sends this current to the charging circuit 12. A power transmission unit 50 connected to the external power supply 2 is also provided. The power transmission unit 50 includes a power transmission coil 51 that transmits electric power from the external power source 2 by changing it to a magnetic field, and a charge control unit 52 that controls supply of power to the power transmission coil 51. The charging control unit 52 is connected to a receiving circuit 57 that demodulates the received wireless communication. A reception antenna 57 a that receives a radio signal from the vehicle 10 is connected to the reception circuit 57.

  When the vehicle-side control unit 11 is parked and is not wirelessly communicating with the electronic key 20, the vehicle-side control unit 11 generates a power transmission request signal indicating that a magnetic field is emitted to the power transmission unit 50, and transmits the generated signal. Input to the circuit 18. The transmission circuit 18 modulates the power transmission request signal into a radio wave having a predetermined frequency. The transmission antenna 18a transmits the power transmission request signal modulated by the transmission circuit 18 to the periphery of the vehicle.

  The reception circuit 57 that has received the power transmission request signal from the vehicle 10 via the reception antenna 57 a demodulates the power transmission request signal and supplies the demodulated signal to the charging control unit 52. The charging control unit 52 supplies power from the external power source 2 to the power transmission coil 51 while receiving this signal. The power transmission coil 51 converts electric power supplied from the external power source 2 into a magnetic field (alternating magnetic field) and radiates this magnetic field.

  When the power receiving coil 41 receives the magnetic field from the power transmitting coil 51, the power receiving coil 41 converts the received magnetic field into a current (alternating current). Then, the alternating current is sent to the charging circuit 12. The charging circuit 12 converts the alternating current into a direct current and sends it to the battery unit 13.

  When the vehicle 10 and the electronic key 20 perform wireless communication, the vehicle 10 stops transmitting the power transmission request signal to the power transmission unit 50. Since no magnetic field is transmitted from the power transmission coil 51, wireless communication between the vehicle 10 and the electronic key 20 can be suitably performed.

Next, the technical idea that can be grasped from the above embodiment and other examples will be described below.
(A) In the vehicular communication system according to any one of claims 1 to 6, the control unit stops charging the battery when the switch is operated and the wireless communication is started. A vehicle communication system.

  According to this configuration, wireless communication between the vehicle and the electronic key can be executed without being disturbed by the magnetic field due to charging.

T ... Number of transmissions, 2 ... External power supply, 5 ... Charging cable, 10 ... Vehicle, 10a ... Charging port, 11 ... Vehicle side control unit, 11a ... Memory, 12 ... Charging circuit, 13 ... Battery unit, 13a ... Voltage sensor, DESCRIPTION OF SYMBOLS 14 ... Motor, 16 ... Door lock apparatus as vehicle equipment, 17, 27 ... Reception circuit, 17a, 27a, 57a ... Reception antenna, 18, 28 ... Transmission circuit, 18a, 28a ... Transmission antenna, 19 ... Door handle switch, DESCRIPTION OF SYMBOLS 20 ... Electronic key, 21 ... Key side control part, 21a ... Memory, 30 ... Charging device, 36 ... Power supply plug, 36a ... Changeover switch, 39 ... Switch element, 41 ... Power receiving coil, 50 ... Power transmission unit, 51 ... Power transmission coil 52... Charge control unit, 57... Reception circuit.

Claims (6)

In the vehicle communication system for operating the in-vehicle device using the wireless communication performed with the electronic key, triggered by the operation of the switch provided in the vehicle including the battery that can be charged from the external power source,
A vehicle communication system comprising a control means for reducing or reducing a charging current amount to the battery when the vehicle detects that the switch is operated during charging of the battery. The vehicle communication system according to claim 1,
The control means is a vehicle communication system that recovers a charging current amount to the vehicle after the vehicle-mounted device is activated. In the vehicle communication system according to claim 1 or 2,
If the wireless communication is not established, the control means tries the wireless communication with the electronic key again. If the wireless communication is still not established, the control means recovers the charging current amount to the vehicle. system. In the vehicle communication system according to any one of claims 1 to 3,
The switch is provided on a door handle of the vehicle, and the vehicle-mounted device is a vehicle communication system that is a door lock device that locks and unlocks the door of the vehicle. In the vehicle communication system according to any one of claims 1 to 4,
The vehicle communication system, wherein the battery is charged by connecting the vehicle and the external power source through a charging cable. In the vehicle communication system according to any one of claims 1 to 4,
A power transmission unit having a power transmission coil that converts power from the external power source into a magnetic field when receiving a power transmission request signal indicating that power transmission is requested from a parked vehicle;
A power receiving coil that is provided in the vehicle and converts a magnetic flux radiated from the power transmitting coil into a current used for charging the battery;
The control means is a vehicular communication system that continuously transmits the power transmission request signal during parking, and stops transmitting the power transmission request signal when it is detected that the switch has been operated.

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