JP2012065503A - Power supply device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an electric shock due to breakage of a high-voltage storage battery mounted on a vehicle body when a hybrid vehicle or an electric vehicle collides.SOLUTION: When a collision is predicted and a high-voltage interruption request signal is output (200), a relay switch of a battery pack is interrupted (202) to control a DC-DC converter, thereby supplying power stored in a capacitor to an electrically heated catalytic device. Thus the residual energy of the capacitor is discharged (204).

Description

  The present invention relates to a vehicle power supply device, and more particularly to a vehicle power supply device used in a vehicle such as a hybrid vehicle.

  In recent years, in consideration of environmental problems and the like, hybrid vehicles and electric vehicles that run using both a motor and an engine have attracted attention.

  Such hybrid vehicles and electric vehicles are equipped with a storage battery for supplying electric power to the motor. As the storage battery, for example, a secondary battery or a capacitor represented by a nickel-cadmium battery, a nickel-hydrogen battery, a lithium ion battery, or the like that can be repeatedly charged and discharged is used. The storage battery is housed in a case and mounted on the vehicle body as a battery pack.

  By the way, since the storage battery mounted in a hybrid vehicle or an electric vehicle has a high voltage, it is necessary to prevent an electric shock by damaging the battery back due to a collision or the like.

  Therefore, for example, it is conceivable to apply a structure (for example, Patent Documents 1 and 2 etc.) that prevents interference of components at the time of a collision.

  For example, the technique described in Patent Document 1 proposes a mounting structure that does not interfere with the ECU even if the transmission moves backward due to a collision or the like.

  Moreover, in the technique described in Patent Document 2, an in-vehicle structure of a battery pack is proposed in which the battery pack moves when an impact is applied.

Japanese Patent Laid-Open No. 2008-37300 Japanese Patent Laid-Open No. 2007-230329

  However, as in the techniques of Patent Documents 1 and 2, it is possible to prevent an electric shock at the time of a collision, etc. by adopting a structure that suppresses interference of components, but because there are restrictions on the layout of the vehicle, Since structures such as Patent Documents 1 and 2 cannot be easily adopted, there is room for improvement.

  The present invention has been made in consideration of the above facts, and an object thereof is to reliably prevent electric shock at the time of a collision.

  In order to achieve the above object, the invention described in claim 1 is a storage battery that stores electric power, and an electric storage that can store electric power of the storage battery and supply it to an in-vehicle device in order to drive a driving means for driving an automobile. Switch means for electrically connecting and disconnecting the storage battery, energizing means for energizing the in-vehicle device, acquisition means for acquiring a connection disconnection request for the storage battery, and the acquiring means When the connection disconnection request is acquired by the control unit, the switch unit is controlled to disconnect the electrical connection of the storage battery, and the energization is performed so that the electric power stored in the storage unit is supplied to the in-vehicle device. And a control means for controlling the means.

  According to the first aspect of the present invention, the battery includes the storage battery that stores electric power and the storage means that can store the electric power of the storage battery and supply it to the in-vehicle device in order to drive the driving means for driving the automobile. That is, by temporarily storing the power of the storage battery in the power storage means and driving the drive means such as a travel motor, the vehicle can run and power can be supplied to the in-vehicle device.

  Here, the switch means is capable of electrically connecting and disconnecting the storage battery. That is, the power can be turned on and off by the switch means.

  In addition, the in-vehicle device can operate the in-vehicle device using the power stored in the storage battery or the power storage unit by being energized by the energization unit.

  In addition, the acquisition unit acquires a storage battery connection cutoff request. For example, as in the second aspect of the invention, a collision prediction signal is acquired as a connection cutoff request, or a collision detection signal or a stop signal indicating a stop of an automobile is acquired as a connection cutoff request.

  In the control means, when the connection cutoff request signal is acquired by the acquisition means, the switch means is controlled so as to cut off the electrical connection of the storage battery, and the electric power stored in the power storage means is supplied to the in-vehicle device. Thus, the energization means is controlled.

  That is, when a connection disconnection request signal is acquired at the time of a collision or the like, the power supply from the storage battery is interrupted by the switch means, and the remaining energy stored in the power storage means such as a capacitor is discharged to the in-vehicle device by the energization means. Therefore, it is possible to reliably prevent an electric shock during a collision or the like.

  In addition, as an in-vehicle device, an electrically heated catalyst device that heats a catalyst provided in an exhaust gas path can be applied as in the invention described in claim 3.

  Further, as the energization means, a DC-DC converter or a relay switch connected between the power storage means and the vehicle-mounted device can be applied as in the invention described in claim 4.

  As described above, according to the present invention, the electrical connection of the storage battery is interrupted and the electric power stored in the power storage means is discharged to the in-vehicle device, so that it is possible to reliably prevent electric shock at the time of collision. effective.

It is a figure showing the schematic structure of the power supply device for vehicles concerning the embodiment of the invention. It is a figure which shows an example of the collision prediction system which outputs the collision prediction signal as a high voltage interruption | blocking request | requirement signal. It is a flowchart which shows an example of the flow of the collision prediction process performed by collision judgment ECU in a collision prediction system. It is a flowchart which shows an example of the flow of the process performed with the control apparatus 30 of the vehicle power supply device 10 concerning embodiment of this invention. It is a figure which shows schematic structure of the modification of the vehicle power supply device concerning embodiment of this invention.

  Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of a vehicle power supply device according to an embodiment of the present invention.

  The vehicle power supply device 10 according to the embodiment of the present invention will be described as an example mounted on a hybrid vehicle including an engine and a motor. In the present embodiment, an example of mounting on a hybrid vehicle will be described. However, the present invention is not limited to this, and may be applied to a plug-in hybrid vehicle or an electric vehicle.

  A vehicle power supply device 10 according to an embodiment of the present invention includes a battery pack 12 that stores electric power for traveling such as a hybrid vehicle. The vehicle power supply device 10 operates the traveling motor 14 using the electric power stored in the battery pack 12.

  As shown in FIG. 1, the battery pack 12 includes a high voltage battery 16 and relay switches 18 and 20, and relay switches 18 and 20 are connected to output terminals of the high voltage battery 16, respectively.

  The battery pack 12 is connected to a capacitor 22 and an inverter 24 for driving the motor 14. The voltage of the high voltage battery 16 is charged in the capacitor 22, and power is supplied from the capacitor 22 to the inverter 24. . As a result, the motor 14 is driven by the inverter 24 and the hybrid vehicle can travel.

  Further, the battery pack 12 is connected to an electrically heated catalyst device 28 via a DC-DC converter 26.

  The electrically heated catalyst device 28 is provided in the exhaust gas path of the engine and purifies the exhaust gas. Further, the electric heating type catalyst device 28 does not start the engine for heating the catalyst because the catalyst is cooled by the traveling by the traveling motor 14 with the engine stopped and the exhaust gas purification ability is lowered. Further, the system heats the catalyst.

  Further, the vehicle power supply device 10 according to the present embodiment includes a control device 30, and the control device 30 includes the relay switches 18 and 20 provided in the battery pack 12 and the DC-DC converter 26. Are connected, and the ON / OFF of the relay switches 18 and 20 and the DC-DC converter 26 is controlled by the control device 30.

  By the way, since the voltage of the battery pack 12 mounted on the hybrid vehicle or the like is a high voltage as in the present embodiment, it is necessary to prevent an electric shock at the time of a collision or the like. In the power supply device 10, when it is necessary to cut off the high voltage part due to a collision or the like, the control device 30 controls to cut off the relay switches 18 and 20 provided in the battery pack 12. As a result, the high-voltage power supply from the battery pack 12 is cut off, so that an electric shock during a collision can be prevented.

  However, in the present embodiment, since the electric power for driving the inverter 24 is stored in the capacitor 22, it cannot be said that the electric shock is surely prevented only by cutting off the relay switches 18 and 20 of the battery pack 12.

  Therefore, in the present embodiment, when the control device 30 acquires the high voltage cutoff request signal, the DC-DC converter 26 is controlled to supply the electric power stored in the capacitor 22 to the electric heating catalyst device 28. As a result, the electric power stored in the capacitor 22 is discharged. As a result, it is possible to reliably prevent an electric shock during a collision or the like.

  The high voltage cutoff request signal is obtained from, for example, a collision detection signal obtained from an acceleration sensor or a collision detection sensor, a stop signal obtained from a vehicle speed sensor or an engine ECU, or a pre-crash sensor such as a millimeter wave radar. Although a collision prediction signal or the like can be applied, in this embodiment, an example in which a collision prediction signal is applied will be described.

  FIG. 2 is a diagram illustrating an example of a collision prediction system that outputs a collision prediction signal as a high voltage cutoff request signal.

  As shown in FIG. 2, the collision prediction system includes a front millimeter wave radar 40 for detecting a distance to a front obstacle, a front side millimeter wave radar 42 for detecting a distance to a front side obstacle, Stereo camera 44 for photographing the front, rear millimeter wave radar 46 for detecting the distance to the obstacle behind, rear side millimeter wave radar 48 for detecting the distance to the obstacle behind, and collision A determination ECU (Electronic Control Unit) 50 is provided, and each is connected to a bus 52. The front millimeter wave radar 40, the front side millimeter wave radar 42, the stereo camera 44, the rear side millimeter wave radar 46, and the rear side millimeter wave radar 48 monitor the vehicle periphery and output the monitoring result to the collision determination ECU 50.

  The front millimeter-wave radar 40 is provided, for example, near the center of the front grille, and the front side millimeter-wave radar 42 is provided near both ends in the vehicle width direction in the bumper, and emits millimeter waves to the front and front sides of the vehicle, respectively. Thus, it is provided to receive the radio wave reflected from the object and measure the distance to the object, the relative speed with the own vehicle, and the like based on the propagation time and the frequency difference caused by the Doppler effect. Further, the rear millimeter wave radar 46 and the rear side millimeter wave radar 48 are provided in a rear bumper or the like, and receive the radio waves reflected from the object by emitting millimeter waves to the rear and rear sides of the vehicle, It is provided to measure the distance to the object, the relative speed with the host vehicle, and the like based on the propagation time and the frequency difference caused by the Doppler effect.

  The stereo camera 44 is provided in the vicinity of the center above the front windshield glass, and is provided for photographing the front of the vehicle to detect surrounding obstacles and to measure the distance to the obstacles. Note that the stereo camera 44 can predict a collision even with an omitted configuration.

  Then, the collision determination ECU 50 obtains the detection results of the front millimeter wave radar 40, the front side millimeter wave radar 42, the stereo camera 44, the rear millimeter wave radar 46, and the rear side millimeter wave radar 48 and performs a collision prediction.

  Next, collision prediction by the collision prediction system configured as described above will be described. FIG. 3 is a flowchart illustrating an example of the flow of a collision prediction process performed by the collision determination ECU 50 in the collision prediction system.

  In step 100, the distance to the obstacle is input, and the process proceeds to step 102. That is, detection results of the front millimeter wave radar 40, the front side millimeter wave radar 42, the stereo camera 44, the rear side millimeter wave radar 46, the rear side millimeter wave radar 48, and the like are input.

  In step 102, the relative speed is calculated, and the routine proceeds to step 104. For example, the relative speed is calculated from the distance to the obstacle detected every predetermined time by the millimeter wave radar. Note that the relative speed may be calculated by obtaining the distance by performing image processing on the photographing result of the stereo camera 44.

  In step 104, the detection result of the millimeter wave radar is newly input, and the process proceeds to step 106.

  In step 106, the time t until the collision is calculated, and the routine proceeds to step 108. That is, the distance to the obstacle detected by the front millimeter wave radar 40, the front side millimeter wave radar 42, the stereo camera 44, the rear side millimeter wave radar 46, the rear side millimeter wave radar 48, etc., and the relative velocity calculated in step 102. To t is calculated.

  In step 108, it is determined whether or not the calculated time t is smaller than a predetermined time. If the determination is affirmative, the process proceeds to step 110, and a collision prediction signal is output as a high voltage cutoff request signal. If the determination is negative, the process returns to step 100 and the above process is repeated.

  That is, in this embodiment, collision prediction is performed by calculating the collision prediction time. For the collision prediction, other methods may be applied instead of calculating the collision prediction time.

  Then, the flow of the process performed with the control apparatus 30 of the vehicle power supply device 10 concerning embodiment of this invention is demonstrated. FIG. 4 is a flowchart showing an example of the flow of processing performed by the control device 30 of the vehicle power supply device 10 according to the embodiment of the present invention.

  In step 200, it is determined by the control device 30 whether or not there is a high voltage cutoff request signal. That is, it is determined whether or not a collision prediction signal is output from the collision determination ECU 50, and the process waits until the determination is affirmed and the process proceeds to step 202.

  In step 202, the relay switches 18 and 20 of the battery pack 12 are turned off, and the routine proceeds to step 204. That is, the control device 30 controls the relay switches 18 and 20 to cut off the voltage supply from the battery pack 12.

  Subsequently, in step 204, the electrically heated catalyst device (EHC) 28 is driven to end a series of processes. That is, the control device 30 controls the DC-DC converter 26 to supply the electric power stored in the capacitor 22 to the electric heating catalyst device 28, thereby discharging the remaining energy of the capacitor 22.

  As described above, in the present embodiment, when there is a high voltage cutoff request, the power supply from the battery pack 12 is reliably shut off by the relay switches 18 and 20 and the power stored in the capacitor 22 is electrically heated. Since it is supplied to the catalytic converter 28 and reliably discharged as thermal energy, it is possible to reliably prevent an electric shock during a collision or the like.

  The vehicle power supply device 10 is not limited to the configuration described in the above embodiment. For example, the vehicle power supply device shown in FIGS. 5A and 5B can be applied.

  In FIG. 5A, the voltage of the battery pack 12 is boosted and supplied. That is, the capacitor 22 and the boost converter 32 are connected to the battery pack 12, and the capacitor 23 and the inverter 24 are connected to the output of the boost converter 32. In this example, power from the battery back 12 is stored in the capacitor 22, and the power stored in the capacitor 22 is boosted by the boost converter 32 and stored in the capacitor 23. The boosted power stored in the capacitor 23 is supplied to the inverter 24 and the DC-DC converter 26. Even in such a configuration, the residual energy of the capacitors 22 and 23 is discharged by performing the process of FIG. 4 as in the above embodiment, so that it is possible to reliably prevent an electric shock during a collision or the like. it can.

  In FIG. 5B, relay switches 34 and 36 are provided in place of the DC-DC converter 26 in the above embodiment. That is, in the above-described embodiment, when power is supplied to the electrically heated catalyst device 28, the voltage is supplied after being converted by the DC-DC converter 26, but the voltage is not simply adjusted as the relay switches 34 and 36. Alternatively, the electric heating type spot sale device 28 may be supplied as it is.

  In the above embodiment, the vehicle power supply device 10 has been described as supplying power to the traveling motor 14 and the electrically heated catalyst device 30, but the power supply destination is not limited to this. Alternatively, other in-vehicle devices may be applied. Moreover, when supplying electric power to in-vehicle devices other than the electrically heated catalyst device 30, an electric vehicle may be applied instead of a hybrid vehicle.

  In the above embodiment, the electrically heated catalyst device 28 is described as an example of the in-vehicle device to which the electric power stored in the capacitor 22 is discharged. However, the present invention is not limited to this. You may make it discharge to various heaters, such as a seat heater, and other vehicle equipment.

DESCRIPTION OF SYMBOLS 10 Power supply device for vehicles 12 Battery pack 14 Motor 16 High voltage battery 18, 20 Relay switch 22, 23 Capacitor 24 Inverter 26 DC-DC converter 28 Electric heating type catalyst device 30 Controller 34, 36 Relay switch

Claims (4)

A storage battery for storing electric power;
Electric storage means for storing electric power of the storage battery to drive a driving means for driving an automobile, and supplying the electric power to an in-vehicle device;
Switch means for electrical connection and disconnection of the storage battery;
Energization means for energizing the in-vehicle device;
Obtaining means for obtaining a connection disconnection request of the storage battery;
When the acquisition unit obtains the connection cutoff request, the switch unit is controlled to cut off the electrical connection of the storage battery, and the electric power stored in the storage unit is supplied to the in-vehicle device. Control means for controlling the energization means;
A vehicle power supply device comprising:   The vehicle power supply device according to claim 1, wherein the acquisition unit acquires a collision prediction signal as the connection cutoff request.   3. The vehicle power supply device according to claim 1, wherein the in-vehicle device is an electrically heated catalyst device that heats a catalyst provided in an exhaust gas path. 4.   The vehicular power supply device according to any one of claims 1 to 3, wherein the energization unit includes a DC-DC converter or a relay switch connected between the power storage unit and the in-vehicle device.

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