JP2007223471A - Vehicular power supply control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular power supply control device capable of controlling the automatic charging as requested by a user. <P>SOLUTION: The vehicular power supply control device comprises a battery 2, a generator 1 connected to the battery 2 in a chargeable manner, a power supply ECU 10 for automatically charging the battery 2 by generating the power by the generator 1 when a stopped state is detected by an ECU 16 capable of detecting the stopped state. By providing a switch 15 for transmitting a request command to the automatic charging from a user to the power supply ECU 10, an intention of the user of the automatic charging or not can be transmitted to the power supply ECU 10. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicular power supply control device, and more particularly to a vehicular power supply control device that controls charging of power storage means that is a vehicular power supply.

2. Description of the Related Art Conventionally, a power supply circuit that performs a charging operation when the amount of charge of a power storage unit is equal to or less than a predetermined value when the vehicle is stopped is known (see, for example, Patent Document 1). This power supply circuit is configured to drive the engine if the capacity of the power storage means is equal to or less than a predetermined value when the vehicle is in a running stop state, generate power with the power generation device, and charge the engine when the capacity of the power storage means exceeds a predetermined value. Is automatically stopped.
JP 7-23504 A

  However, the prior art as described above is preferable from the viewpoint of securing the charging capacity of the power storage means. However, when the system side uniquely drives or stops the engine, such a system-based operation is advantageous depending on the situation. In some cases, it was bad, and the user could not cope with such an inconvenient case. For example, even if the user wants to stop the engine immediately, the user cannot stop the engine himself and has to wait for the engine to stop until the capacity of the power storage means is charged to a predetermined value or more.

  Therefore, an object of the present invention is to provide a vehicle power supply control device capable of controlling automatic charging that meets a user's request.

In order to solve the above problems, as the present invention, a power storage means,
Power generation means connected to the power storage means in a chargeable manner;
Stop state detection means capable of detecting a stop state;
In a vehicle power supply control device having a control means for causing the power generation means to generate power and automatically charging the power storage means when the stop state is detected by the stop state detection means,
A vehicle power supply control device is provided, comprising a transmission means for transmitting a request command for automatic charging from a user to the control means.

  Here, desirably, the transmission unit is an operation switch that transmits a selection command as to whether or not the automatic charging can be performed by the control unit and that manually receives the selection command.

  Further, the control means may operate an engine that is a power source of the power generation means to cause the power generation means to generate power. Furthermore, you may provide the alerting | reporting means to notify a user of the operation state of the automatic charge by the said control means.

  According to the present invention, it is possible to control automatic charging that meets a user's request.

  The best mode for carrying out the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of a system to which an embodiment of a vehicle power supply control device of the present invention is applied. Vehicles are equipped with various electrical loads. Examples of in-vehicle electric loads include air conditioners, rear defoggers, rear wipers, mirror heaters, seat heaters, audio, lamps, cigar sockets, various ECUs (Electronic Control Units), and solenoid valves. These electric loads are merely examples and do not limit the types of loads. The power source of these electric loads is the generator 1 and the battery 2. The generator 1 and the battery 2 supply power to each electric load via the power line 14.

  The generator 1 generates electric power based on the output of an engine for running the vehicle. The electric load generated by the electric power generated by the generator 1 or the battery 2 is charged. An alternator is a specific example of the generator 1 that uses an engine as a power source. The battery 2 can be charged by regenerating the motor (electric motor). Therefore, the generator 1 may include a motor capable of regenerative control. By regeneratively controlling the motor, the battery 2 can be charged via the inverter.

  Similarly to the generator 1, the battery 2 supplies power to the electric load via the power supply line 14. The battery 2 supplies power to the electric load when the power supply capability of the generator 1 is insufficient, and supplies power to a starter (not shown) when starting a power source such as an engine. The starter receives power supply from the battery 2 and starts a power source such as an engine. Specific examples of the battery 2 include a lead battery, a nickel metal hydride battery, and a lithium ion battery. The battery 2 may be replaced with an electric double layer capacitor. The battery 2 may be a combination of any of a lead battery, a lithium ion battery, a nickel metal hydride battery, and an electric double layer capacitor.

  Further, when the generator 1 is stopped, power can be supplied from the battery 2 to the electric load. For example, the electric power required when the engine is stopped and the alternator is in a stopped state can supply electric power from the battery 2 to the electric load.

  The switch 6 is an operation switch that receives an engine start / stop instruction from a user (driver). A specific example of the switch 6 is an ignition switch (key switch). There are also types that start and stop the engine by inserting a key into the key cylinder, and there are also momentary button switch types. When the switch 6 is ON, the power line 14 that has been cut off by the switch 6 is energized. Conversely, when the switch 6 is OFF, the power line 14 is cut off. When the driver wants to start the engine, he operates the switch 6 to the ON side, and when he wants to stop the engine, he operates the switch 6 to the OFF side.

  The relay 9 corresponds to a switch that switches whether to supply power to the engine ECU 12. When relay 9 is energized, power is supplied to engine ECU 12, and when relay 9 is de-energized, power is not supplied to engine ECU 12. Energization of the relay 9 is performed via a diode OR circuit including diodes 7 and 8. That is, a path through which the relay 9 is energized through the diode 7 when the switch 6 is turned on, and a path through which the relay 9 is energized through the diode 8 when the power supply ECU 10 outputs a Hi signal (drive current) through which the relay 9 is energized. have.

  When the switch 6 is turned on, electric power from the battery 2 or the like is supplied to an electric load or the like existing downstream of the switch 6, and the relay 9 is energized via the diode 7, and electric power from the battery 2 or the like is supplied to the engine ECU 12. It is configured to be supplied. The engine ECU 12, which has started supplying power, energizes the starter after a predetermined initial process to start the engine.

  On the other hand, when the switch 6 is turned OFF, power supply from the battery 2 or the like to the electric load or the like existing downstream of the switch 6 is cut off, and current through the diode 7 does not flow to the relay 9. Therefore, when the switch 6 is OFF, whether or not electric power is supplied to the engine ECU 12 depends on whether or not the power supply ECU 10 outputs a Hi signal (driving current) for energizing the relay 9. Even when the switch 6 is OFF, power is continuously supplied to the engine ECU 12 when the power supply ECU 10 supplies a drive current to the relay 9, and the operating state of the engine continues. If the power supply ECU 10 stops supplying the drive current to the relay 9 when the switch 6 is OFF, the power supply from the battery 2 or the like to the engine ECU 12 is stopped and the operation of the engine is also stopped.

  When there is no diode 7, the power supply ECU 10 inputs the ON / OFF state of the switch 6 of the switch 6, and the power supply ECU 10 controls the power supply to the engine ECU 12 based on the ON / OFF state of the switch 6. It may be. When the power supply ECU 10 detects the ON state of the switch 6, the power supply ECU 10 energizes the relay 9 by causing a drive current to flow through the relay 9 via the diode 8. Thereby, the electric power from the battery 2 or the like is supplied to the engine ECU 12 as described above. The engine ECU 12 that has started supplying power can energize the starter and start the engine after a predetermined initial process. On the other hand, when the power supply ECU 10 detects the OFF state of the switch 6 and determines that there is no problem even if the engine is stopped in accordance with a predetermined condition, the power supply ECU 10 stops supplying the drive current to the relay 9. As a result, similarly to the above, power supply from the battery 2 or the like to the engine ECU 12 is stopped and the operation of the engine is also stopped.

  The various ECUs 16 are the senders of state information (such as vehicle speed information, engine speed information, brake information, side brake information, shift position information such as neutral and parking, etc.) that is related to the vehicle required by the power supply ECU 10. It is. The power supply ECU 10 may directly acquire vehicle state information from a predetermined sensor that detects vehicle state information such as vehicle speed information from a vehicle speed sensor and shift position information from a shift position sensor. Is not limited to the ECU.

  The power supply ECU 10 determines whether or not the vehicle is stopped based on vehicle state information from the various ECUs 16. For example, the power supply ECU 10 determines that the vehicle is in a stopped state when the shift position information is in a parking state, and determines that the vehicle is not in a stopped state when the shift position information is not in a parking state. Alternatively, the power supply ECU 10 determines that the vehicle is stopped when the vehicle speed is zero, and determines that the vehicle is not stopped when the vehicle speed is not zero. It is also possible to determine the stop state by combining any of parking information, vehicle speed information, brake information, side brake information, and engine speed information. For example, it may be determined that the vehicle is stopped when the vehicle speed is zero and the vehicle is parked.

  The power supply ECU 10 detects the temperature of the battery 2 when the various ECUs 10 detect that the vehicle is stopped (when it is determined that the vehicle is stopped), and the current sensor 4 detects the charge / discharge current of the battery 2. Based on information from the voltage sensor 5 that detects the voltage of the battery 2, the charging switch 15 that accepts a selection command to determine whether or not automatic charging can be performed from the driver, the generator 1 generates power and automatically charges the battery 2. . The automatic charging will be described later in detail.

  Further, the power supply ECU 10 detects the current value or voltage value of the battery 2 using the current sensor 4 or the voltage sensor 5 to indicate how much capacity of the battery 2 remains “Charging rate (SOC: State of Charge) ”. The charge rate indicates the remaining capacity with respect to the full charge capacity. The power supply ECU 10 calculates the charging rate (remaining capacity) by, for example, integration (integration) of the charging / discharging current of the battery 2. This is because the rate of change over time in the amount of electricity (the capacity of the battery 2) corresponds to the current. Since the remaining capacity corresponds to a value obtained by subtracting the discharge capacity discharged from the battery 2 from the capacity when the battery 2 is fully charged, the power supply ECU 10 uses the current sensor 4 or the like to connect the power line connected to the battery 2 to the battery 2. The charge rate (remaining capacity) can be calculated by monitoring the charge / discharge current and recording the history in the memory. Note that the initial capacity at the time of full charge is stored in the memory.

  The power supply ECU 10 may estimate the charging rate by measuring the minimum value of the voltage of the battery 2 at the initial stage of discharging. Since it is known that there is a correlation between the minimum value caused by the voltage drop at the initial stage of discharge and the charging rate, the power supply ECU 10 can estimate the charging rate based on the correlation (for example, map data). .

  The power supply ECU 10 may calculate the charging rate and the full charge capacity by measuring the internal resistance of the battery 2 at the initial stage of discharging. The internal resistance is calculated from the initial discharge current and the initial discharge voltage. It is known that there is a correlation between the internal resistance and the charging rate, and the internal resistance and the full charge capacity.

  FIG. 4C is a calculation map of the charging rate with respect to the internal resistance of the battery 2. The map shown in FIG. 4C has a feature that the charging rate is calculated higher as the temperature becomes lower in consideration of the temperature characteristics of the battery 2. The power supply ECU 10 calculates a charging rate corresponding to the internal resistance and temperature of the battery 2 based on the map shown in FIG.

  FIG. 4D is a calculation map of the full charge capacity with respect to the internal resistance of the battery 2. The map shown in FIG. 4D has a characteristic that the full charge capacity is calculated to be higher as the temperature is lower in consideration of the temperature characteristics of the battery 2. The power supply ECU 10 calculates the full charge capacity corresponding to the internal resistance and temperature of the battery 2 based on the map shown in FIG.

  If battery 2 can be replaced with an electric double layer capacitor and its capacitance is known, power supply ECU 10 charges electric double layer capacitor based on the voltage value and capacitance of electric double layer capacitor. The rate (remaining capacity) can be calculated.

  In addition, charge / discharge control is executed so that the charge rate is maintained within the SOC management range having a predetermined charge rate as an upper and lower limit value. By providing the SOC management width, it is possible to prevent the progress rate of deterioration of the battery 2 due to, for example, excessive charging / discharging from being accelerated.

  Furthermore, the power supply ECU 10 determines the deterioration state of the power supply, and for example, determines the deterioration state according to the degree of decrease in the power supply voltage when the engine is started. When starting the engine, a very large current (also called inrush current) flows from the power supply to the large-capacitance capacitors provided in the starter and in-vehicle electronic devices. If the voltage can be maintained, it can be considered that the power supply has not deteriorated, and if the high power supply voltage cannot be maintained, it can be considered that the power supply has deteriorated. Therefore, the power supply ECU 10 determines that the power supply is deteriorated when the minimum value of the power supply voltage that drops when the starter is started is equal to or less than a predetermined threshold as an example of a method for determining the deterioration state of the power supply. The power supply ECU 10 may determine that the power supply is deteriorated when the time until the power supply voltage value drops to the predetermined voltage value when a predetermined large current is passed is equal to or less than a predetermined threshold value. That is, the deterioration state of the power source is determined by measuring the discharge duration until the power source voltage value reaches a predetermined voltage value when a large current is passed. It can be considered that the longer the discharge duration, the less the deterioration.

  The power supply ECU 10 includes a plurality of ROMs such as a ROM for storing control programs and control data, a RAM for temporarily storing control program processing data, a CPU for processing control programs, and an input / output interface for exchanging information with the outside. It is comprised by the circuit element of. The power supply ECU 10 is not limited to one control unit, and may be a plurality of control units so that control is shared.

  The charge switch 15 is an operation switch that manually accepts a selection command for whether or not automatic charging can be performed from a driver and transmits the selection command to the power supply ECU 10. For example, a momentary type, an alternate type, or a push-pull type button switch. The driver turns on the charging switch 15 when the automatic charging may be permitted, and turns off the charging switch 15 when not permitted. The power supply ECU 10 that detects the ON state of the charging switch 15 starts or starts the automatic charging, and the power supply ECU 10 that detects the OFF state of the charging switch 15 stops the automatic charging.

  The display device 13 is a notification means for informing the driver of the operation state of automatic charging by the power supply ECU 10. For example, a blinking lamp such as an LED or a filament, a display capable of visually recognizing a driver of a detailed operation state (for example, a current charging state of the battery 2 or an expected time until the end of automatic charging). . The power supply ECU 10 turns on the lamp during the automatic charging operation or displays a detailed operation state of the automatic charging on the display, and turns off the lamp or stops the automatic charging operation state during the automatic charging stop. Or hide.

  Now, automatic charging by the power supply ECU 10 will be described in detail. The power supply ECU 10 sets a charging voltage applied to the battery 2 and a target charge amount (target supply amount) to be supplied to the battery 2 in order to perform automatic charging. The power supply ECU 10 adjusts the output voltage of the generator 1 so as to become the set charging voltage, and adjusts the output current and output time of the generator 1 so as to charge (complementary charging) the set target charging amount. .

  The power supply ECU 10 sets a charging voltage to be applied to the battery 2 according to FIG. FIG. 3A is a map for setting the charging voltage with respect to the temperature of the battery 2. FIG. 3B is a map for setting the charging voltage with respect to the charging rate of the battery 2. The map shown in FIG. 3A is characterized in that the charging voltage at the low temperature is set higher than the charging voltage at the high temperature in order to prevent overcharge at the high temperature and compensate for the decrease in charging efficiency at the low temperature. have. In the map shown in FIG. 3B, the charging voltage at the low charging rate is higher than the charging voltage at the high charging rate in order to extend the battery life at the high charging rate and shorten the charging time at the low charging rate. It has the characteristic set to voltage. The power supply ECU 10 sets a charging voltage corresponding to the temperature of the battery 2 detected by the temperature sensor 3 based on the map shown in FIG. Or power supply ECU10 sets the charging voltage corresponding to the charging rate computed as mentioned above based on the map shown by FIG.3 (b). The power supply ECU 10 may set the charging voltage based on a map obtained by combining the map shown in FIG. 3A and the map shown in FIG. In addition, since the deterioration of the battery 2 is affected if the charging voltage is too high, it is desirable that the charging voltage specified in the map shown in FIG. 3 is set so as not to affect the deterioration of the battery 2 as much as possible.

  The power supply ECU 10 sets a target charge amount to be supplied to the battery 2 according to FIG. FIG. 4A is a map for setting the target charge amount with respect to the charge rate of the battery 2. The map shown in FIG. 4A differs depending on the type of the battery 2 to be set. The map shown in FIG. 4A has a characteristic that the target charge amount is set higher as the charge rate is lower because the charge amount required to fully charge the battery 2 increases as the charge rate is lower. ing. In addition, the map shown in FIG. 4A is set so that the target charge amount at the low temperature is set higher than the target charge amount at the high temperature in order to prevent overcharge at the high temperature and compensate for the decrease in the charge efficiency at the low temperature. It has the following characteristics. The power supply ECU 10 sets a target charge amount corresponding to the temperature of the battery 2 detected by the temperature sensor 3 and the charge rate calculated as described above, based on the map shown in FIG.

  Here, it is desirable that the power supply ECU 10 corrects the target charge amount according to the deterioration state of the battery 2.

  FIG. 4B is a diagram showing the relationship between the full charge capacity and the correction coefficient. As the nature of the battery, the full charge capacity, which is the capacity that the battery can be charged to the maximum, decreases as the deterioration progresses. Therefore, a “correction coefficient” for correcting the target charge amount set by the map shown in FIG. That is, as shown in FIG. 4 (b), the full charge capacity, which is the capacity that the battery 2 can be charged to the maximum, decreases as the deterioration progresses, so the correction coefficient for the target charge amount increases as the deterioration degree increases. The power supply ECU 10 increases the target charge amount set by the map shown in FIG. 4A to increase the target charge amount. The degree of deterioration may be determined using the above-described method for determining the deterioration state of the power source.

  Now, the operation of the vehicle power supply control device according to this embodiment will be described. FIG. 2 is an example of an operation flow of the vehicle power supply control device according to the present embodiment.

  If the power supply ECU 10 determines that the charging switch 15 is ON in step 2 and the vehicle is stopped in step 4, the power supply ECU 10 proceeds to step 6. The power supply ECU 10 that has shifted to Step 6 outputs a Hi signal for energizing the relay 9 and causes the display device 13 to display a display that informs the driver of the start of automatic charging (Step 6). As a result, the driver can recognize the start of automatic charging. The power supply ECU 10 performs setting of a charging voltage applied to the battery 2 and setting of a target charge amount to be supplied to the battery 2 in order to perform automatic charging (step 8).

  Here, the driver who has made the stop operation operates the switch 6 to the OFF side in order to stop the engine (step 10). At this time, the engine normally stops, but the relay 9 remains energized by the output of the Hi signal from the power supply ECU 10, and the operation of the engine continues. As described above, since the display device 13 is displayed to indicate the start of automatic charging, the driver can grasp why the engine does not stop even when the switch 6 is operated to the OFF side.

  The power supply ECU 10 determines whether or not the charging switch 15 is ON (step 12). When the charging switch 15 is ON, the current sensor 4 measures the charging current to the battery 2, the voltage sensor 5 measures the voltage of the battery 2, and the temperature sensor 3 measures the temperature of the battery 2. (Step 13). The power supply ECU 10 adjusts the output voltage of the generator 1 to the charging voltage set according to FIG. 3 and starts integrating the charging current to the battery 2 (step 14).

  The power supply ECU 10 determines whether or not the integrated value of the charging current to the battery 2 is larger than the target charge amount set according to FIG. 4 (step 16). When the charge current integrated value is larger than the target charge amount (step 16; Yes), it is determined whether or not the voltage of the battery 2 is higher than a charge end voltage V1 described later (step 18), and the charge current integrated value is the target. If it is not larger than the charge amount (step 16; No), it is determined whether or not the voltage of the battery 2 is higher than a charge end voltage V2 described later (step 20). When the voltage of the battery 2 is higher than the charging end voltage V1 at step 18 or when the voltage of the battery 2 is higher than the charging end voltage V2 at step 20, or the power switch ECU 10 turns off the charging switch 15 at step 12. If it is, the Lo signal for de-energizing the relay 9 is output, and a display for informing the driver of the end of automatic charging is displayed on the display device 13 (step 22). When the relay 9 is de-energized, power supply from the battery 2 or the like to the engine ECU 12 is stopped and the operation of the engine is also stopped.

  The voltage of the battery rapidly increases when charging of the battery is completed. Moreover, since the target charge amount is estimated (calculated) as described above, an error is likely to occur. Therefore, in steps 16, 18, and 20, the two charging guards for the charging current to the battery 2 and the voltage of the battery 2 are applied to prevent overcharging and to cope with the estimation error, and to determine the end of automatic charging. ing.

  Even when the charge current integrated value has reached the target charge amount (step 16; Yes), if the voltage of the battery 2 has not reached the charge end voltage V1 (step 18; No), further automatic charging is continued, and the battery 2 Is increased by the charging end voltage V1 (step 18; Yes), it means that the automatic charging is ended. Further, even when the charge current integrated value has not reached the target charge amount (step 16; No), if the voltage of the battery 2 has not reached the charge end voltage V2 (step 20; No), further automatic charging is continued. If the voltage of the battery 2 is increased by the charging end voltage V2 (step 20; Yes), it means that the automatic charging is ended.

  Further, the above-described charging end voltages V1 and V2 are determined based on a map as shown in FIG. As shown in FIG. 5, the charging end voltages V1 and V2 are determined based on the relationship between the charging voltage applied to the battery 2 and the charging current of the battery 2 at that time. The data in FIG. 5 is adapted according to the type of battery 2.

  Therefore, according to the vehicle power supply control apparatus of the present embodiment, the user's intention of whether or not to perform automatic charging can be transmitted to the power supply ECU 10 by the charging switch 15, and automatic charging that meets the user's request is executed. Can be made. In addition, since the display device 13 is provided, the user can recognize the operation state of automatic charging. Further, since the engine is automatically stopped and the automatic charging is stopped, the user can easily leave the vehicle with the engine running.

  The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the present invention. Can be added.

  For example, the transmission means for transmitting a request command for automatic charging from the user to the power supply ECU 10 may be a voice recognition device that recognizes the user's voice and transmits it to the power supply ECU 10 instead of the manual charging switch 15. Alternatively, a touch panel device that selectively displays a request command menu and transmits the selected request command to the power supply ECU 10 may be used. For example, as a command for automatic charging, the user requests an automatic charging end time, an automatic charging operation permission time, and a charging rate for ending automatic charging. Thereby, when the end time, the operation permission time, or the charging rate is reached, the automatic charging is surely terminated, so that it is possible to control the automatic charging that meets the user's request.

  Further, the notification means for notifying the user of the operation state of automatic charging may be a voice output device for notifying visually by the display device 13 but by a voice.

1 is a configuration diagram of a system to which an embodiment of a vehicle power supply control device of the present invention is applied. It is an example of the operation | movement flow of the vehicle power supply control apparatus which concerns on a present Example. It is a map for setting a charging voltage. It is a map for setting a target charge amount. It is a map for determining a charge end voltage.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Generator 2 Battery 3 Temperature sensor 4 Current sensor 5 Voltage sensor 10 Power supply ECU
11 Communication line 12 Engine ECU
14 Power line 15 Charge switch 16 Various ECUs

Claims (5)

Power storage means;
Power generation means connected to the power storage means in a chargeable manner;
Stop state detection means capable of detecting a stop state;
In a vehicle power supply control device having a control means for causing the power generation means to generate power and automatically charging the power storage means when the stop state is detected by the stop state detection means,
A vehicle power supply control device comprising: a transmission unit configured to transmit a request command for automatic charging from a user to the control unit.   The vehicle power supply control device according to claim 1, wherein the transmission unit transmits a selection command as to whether or not the control unit can execute automatic charging.   The vehicle power supply control device according to claim 2, wherein the transmission means is an operation switch that manually receives the selection command.   The vehicular power supply control device according to claim 1, wherein the control unit operates an engine that is a power source of the power generation unit to cause the power generation unit to generate power.   The vehicle power supply control device according to any one of claims 1 to 4, further comprising notification means for notifying a user of an operation state of automatic charging by the control means.

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