JP2005354761A - Battery manager and battery management method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely and sufficiently charge a battery while a vehicle runs especially before an engine stops. <P>SOLUTION: A car navigation apparatus 1 detects a predicted running distance or predicted running time from a present location to a destination. When the predicted running distance or predicted running time is below a predetermined reference distance or reference time, the battery 3 begins to be rapidly charged. The battery 3 can surely be brought into a fully charged state before the engine stops. An output voltage of the battery 3 is prevented from decreasing below a voltage required for starting the engine even if the output voltage of the battery 3 gradually decreases due to a dark current. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a battery management apparatus and a battery management method for managing the state of a battery mounted on a vehicle.

  In an automobile, power from a battery is supplied to a load. Conversely, when power consumption is low in the load, a battery is driven by an alternator as an on-vehicle power generator using a predetermined power such as engine rotation as an energy source. Is charged. For this reason, it is desirable to charge the battery while the automobile is running.

  In an automobile, even if the main power switch is turned off, a dark current flows through an electric circuit such as a load, so that a certain amount of battery power is consumed.

  However, when the automobile engine is stopped, the battery cannot be charged. If such a state is left for an extremely long time, even if the ignition switch is turned on to start the engine next time, the battery may run out and the engine may not be started.

  Considering this, it is desirable to charge the battery as much as possible while the vehicle is running, that is, before the engine is stopped.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a battery management device and a battery management method capable of sufficiently charging a battery reliably while the vehicle is running, particularly before the engine stops. .

  In order to solve the above-described problem, the invention according to claim 1 is a battery management device that manages the state of a battery mounted on a vehicle, and generates power based on engine power and supplies power to the battery. Means for estimating whether or not the vehicle has reached a predetermined range around the destination, and when the estimation means estimates that the vehicle has reached a predetermined range around the destination And a control means for controlling the power generation means so as to increase the supply level of the power supply to the battery.

  A second aspect of the present invention is the battery management apparatus according to the first aspect, wherein the estimation means is configured such that a predicted travel distance from the current position of the vehicle to the destination given from the car navigation apparatus is a predetermined reference. When the distance is less than the distance, it is assumed that the vehicle has reached a predetermined range around the destination.

  A third aspect of the present invention is the battery management apparatus according to the first aspect, wherein the estimation means is configured to have a predetermined reference time for a predicted travel time from the current position of the vehicle and the destination given from the car navigation apparatus. If it is less than the time, it is assumed that the vehicle has reached a predetermined range around the destination.

  Invention of Claim 4 is a battery management apparatus in any one of Claim 1 thru | or 3, Comprising: The battery state detection means which detects the state of the said battery is further provided, The said control means is the said control means, When the battery state detection means detects full charge of the battery, the power generation means is controlled so as to temporarily stop the charge of the battery.

  The invention according to claim 5 is a battery management method for managing the state of the battery mounted on the vehicle, and whether or not the vehicle has reached a predetermined range around the destination by a predetermined estimation means. A first step of estimating and a second step of increasing the supply level of the power supply to the battery when it is estimated that the vehicle has reached a predetermined range around the destination in the first step. A process.

  A sixth aspect of the present invention is the battery management method according to the fifth aspect, wherein the estimation means is a car navigation device, and a predicted travel distance from the current location of the vehicle to the destination is less than a predetermined reference distance. In this case, it is estimated that the vehicle has reached a predetermined range around the destination.

  A seventh aspect of the present invention is the battery management method according to the fifth aspect, wherein the estimating means is a car navigation device, and a predicted traveling time from the current location of the vehicle to the destination is less than a predetermined reference time. In this case, it is assumed that the vehicle has reached a predetermined range around the destination.

  The invention according to claim 8 is the battery management method according to any one of claims 5 to 7, further comprising a third step of detecting a state of the battery, wherein the third step In the second step, when the full charge of the battery is detected, the charge of the battery is temporarily stopped.

  In the battery management device according to the first and fifth aspects of the present invention, when the vehicle reaches a predetermined range around the destination, the supply level of the power supply to the battery is increased. The battery can be reliably charged. Therefore, even if the output voltage of the battery gradually decreases due to dark current or the like after the engine is stopped, it is possible to delay the time when the output voltage of the battery decreases below the voltage necessary for starting the engine. Can be provided.

  In the battery management device according to the second, third, sixth, and seventh aspects, the car navigation device is applied as the estimation means, so that the vehicle reaches a predetermined range around the destination. It can be easily guessed whether or not.

  Since the battery management apparatus according to the fourth and eighth aspects of the invention temporarily stops the charging of the battery when the battery is fully charged, it is possible to prevent overcharging of the battery.

<Configuration>
FIG. 1 is a block diagram showing a battery management apparatus according to an embodiment of the present invention. As shown in FIG. 1, the battery management device calculates a travel prediction distance from a current position to a destination in a car navigation device 1 for estimating a travel prediction distance in an automobile, and the travel prediction distance is predetermined. When the vehicle becomes less than the reference distance, it is assumed that the vehicle has reached a predetermined range around the destination and charging of the battery 3 is started and the capacity of the battery 3 is ensured as much as possible during driving. is there.

  Specifically, this battery management device manages the state of the battery 3 mounted on the vehicle, and is an ignition switch (hereinafter referred to as “IG switch”) as engine state detection means for detecting start and stop of the engine. 5), a voltage sensor (battery state detection means) 7 for detecting the output voltage of the battery 3 as the state of the battery 3, an alternator (power generation means) 9 for adjusting and controlling the charging voltage of the battery 3, and the engine And a central control unit (estimating unit) 13 for controlling the engine control unit (control unit) 11 based on information from the car navigation apparatus 1.

  The car navigation device 1 is installed in a part of an instrument panel of a car, for example, and as shown in FIG. 1, an input device 21 for inputting a destination related to travel of the car by an input operation by an operator, , The destination storage unit 23 for storing the destination of the vehicle input by the operation, the current position detection unit 25 for detecting the current position of the vehicle, and the destination storage unit from the current position detected by the current position detection unit 25 A recommended route search unit 27 that searches for a recommended route to the destination stored in 23, and a predicted travel distance that calculates a predicted travel distance by calculating a route distance of the recommended route searched by the recommended route search unit 27. And an arithmetic unit 29.

  The input device 21 uses existing operation input parts such as a push button, a cross key, or a joystick, and maps information stored in advance on an optical disc (CD-ROM) device or the like to a predetermined display device such as a liquid crystal display panel ( The destination in the map information can be input by the operator's manual operation while being displayed on the display.

  The destination storage unit 23 uses a rewritable nonvolatile storage device such as a flash ROM, and stores the destination input by the input device 21.

  The current position detection unit 25 traces a map by autonomous navigation control based on a vehicle speed pulse from a vehicle speed sensor (not shown) and a direction by geomagnetism from a geomagnetic sensor, and receives a GPS signal transmitted from a GPS satellite through an antenna. When the vehicle position on the map is confirmed using the information contained in the signal and the map information stored in advance on the optical disk device, etc., and a position shift occurs in the trace in autonomous navigation control The current position of the vehicle is detected while performing position correction (map matching).

  The recommended route search unit 27 obtains a road network existing from the current position detected by the current position detection unit 25 to the destination stored in the destination storage unit 23 from map information stored in advance in an optical disk device or the like. The recommended route is searched under conditions such as extraction, shortest time standard, shortest distance standard, or minimum fee standard. Here, in the map information stored in the optical disc apparatus, for example, a road between a node (node) having a unique number and a node with a road width of 3.0 m (one lane) or more is taken into consideration. Each road is identified by a combination of sections (links), and the recommended route search unit 27 searches for a recommended route using data on the road in the optical disc apparatus.

  The predicted travel distance calculation unit 29 calculates, for example, the predicted travel distance from the current location of the automobile to the destination by calculating the total distance of the links between the nodes in the recommended route searched by the recommended route search unit 27. To do.

  The voltage sensor 7 detects the output voltage of the battery 3 and supplies it to the engine control unit 11.

  The alternator 9 includes a generator 31, a regulator 33, and a control unit 35.

  The generator 31 includes a stator coil 31a and a rotor coil 31b.

  The regulator 33 rectifies the generated current generated by the generator 31 and adjusts and outputs the voltage level. The output current is supplied to the battery 3 and charged, and also supplied to various loads.

  The control unit 35 controls the alternator 9 based on the control signal given from the engine control unit 11. For example, the controller 35 performs rectification operation and output voltage adjustment operation of the regulator 33, and on / off control of the power generation operation of the generator 31 and adjustment of the power generation amount. The on / off of power generation and the adjustment of the power generation amount are performed, for example, by turning on / off and adjusting the level of the excitation current supplied to the rotor coil 31b of the generator 31.

  After the IG switch 5 is turned on, the central control unit 13 determines whether the predicted travel distance from the current location of the automobile to the destination given from the car navigation device 1 is less than a predetermined reference distance such as 1 km, for example. When the predicted travel distance becomes less than the reference distance, the alternator 9 is controlled, that is, the regulator 33 rectifies and adjusts the output voltage, and the generator 31 is turned on and off. Then, the power generation amount is adjusted, charging of the battery 3 is started, and a command is given to the engine control unit 11 so as to secure the capacity of the battery 3 as much as possible during traveling.

  The engine control unit 11 controls the state of the battery 3 while controlling an engine (not shown). That is, when the engine is started, the engine control unit 11 controls the alternator 9 to generate electric power and charge the battery 3 or the like. The charging timing of the battery 3 includes charging operation performed at the time of starting the engine in order to compensate for the remaining charge of the battery 3 that has decreased due to wear during parking, and charging when the remaining charge of the battery 3 decreases during traveling. In the invention according to the embodiment, in particular, the central control unit 13 determines that the predicted travel distance from the current location of the automobile to the destination given from the car navigation device 1 is less than a predetermined reference distance. At that time, charging of the battery 3 is started, and the capacity of the battery 3 is secured as much as possible during traveling.

  More specifically, the engine control unit 11 is configured such that the power supply level of the alternator 9 is changed in two stages (normal charge level / rapid charge level). That is, as will be described later, when the central control unit 13 determines that the predicted travel distance given from the car navigation device 1 is less than a predetermined reference distance, the power supply level of the alternator 9 is the normal charge level. Control is performed so that the output voltage of the battery 3 is charged (rapid charge).

  On the other hand, in other cases, when the battery 3 is not fully charged as will be described later, the power supply level of the alternator 9 is set to the normal charge level based on the control in the engine control unit 11, The battery 3 is charged (normal charge).

  Here, the adjustment of the power supply level of the alternator 9 is performed, for example, by using the following three methods alone or in combination. As the first method, there is a method of increasing or decreasing the power supply level of the alternator 9 by changing the adjustment voltage by the regulator 33 of the alternator 9 to change the output voltage of the alternator 9 to high or low. As a second method, there is a method of increasing or decreasing the power supply level of the alternator 9 by changing the level of the excitation current supplied to the rotor coil 31b of the generator 31 of the alternator 9 to high or low. As a third method, there is a method of increasing the power supply level of the alternator 9 by suppressing a shift-up due to an automatic shift operation of a transmission controller (not shown) or promoting a shift-down. In this case, if the shift-up timing by the automatic shift operation is delayed (suppressed), the engine speed increases as a result, and the power generation amount of the alternator 9 increases as compared with the normal shift control. Even when the timing of downshifting by the automatic shift operation is advanced (promoted), the engine speed increases as a result, and the power generation amount of the alternator 9 increases as compared with the normal shift control.

  The engine control unit 11 controls the power supply level of the alternator 9 according to the output voltage of the battery 3 given from the voltage sensor 7 when the engine is started. Here, the charging operation of the battery 3 started when the engine is started is performed until the output voltage of the battery 3 detected by the voltage sensor 7 reaches a predetermined value (for example, 14 V) (fully charged state). .

<Operation>
A solid line G1 in FIG. 2 is a diagram showing a transition of the output voltage of the battery 3 to which the battery management device according to the present embodiment is applied. In FIG. 2, a dotted line G <b> 2 indicates a comparative example in which the central control unit 13 does not perform control based on the determination of the predicted travel distance. Also, time T1 in FIG. 2 corresponds to the time when the central control unit 13 determines that the predicted travel distance from the current location of the vehicle to the destination is less than the reference distance, and the time T2 is determined by the quick charge level. 3 corresponds to the time when the IG switch 5 is turned off (engine stopped), and the time T4 corresponds to the time when the automobile is left for a predetermined period. ing.

  While the automobile is running normally, charging / discharging of the battery 3 is repeated depending on the situation. During this time, unless the battery 3 is fully charged, the power supply level of the alternator 9 is set to the normal charge level based on the control by the engine control unit 11, and the battery 3 is charged (normal charge). The output voltage of the battery 3 in this case is illustrated as being set to 12 V in the period up to time T1 in FIG.

  When the central control unit 13 determines that the predicted travel distance given from the car navigation device 1 is less than the reference distance at time T1, the central control unit 13 controls the engine control unit 11 with an alternator. Command to switch the power supply level of 9 to the quick charge level. Then, the engine control unit 11 changes the adjustment voltage by the regulator 33 of the alternator 9, changes the level of the excitation current supplied to the rotor coil 31b of the generator 31 of the alternator 9, or performs automatic shift of a transmission controller (not shown). The battery 3 is charged (rapidly charged) by increasing the power supply level of the alternator 9 by suppressing upshifting by the operation or promoting downshifting.

  When the engine control unit 11 detects that the output voltage of the battery 3 has reached a predetermined value (for example, 14 V) (full charge) at time T2 based on the detection result of the output voltage from the voltage sensor 7, Stop charging operation temporarily. However, when the output voltage of the battery 3 starts to decrease due to the temporary stop of the charging operation, the battery 3 is again rapidly charged because the predicted travel distance is already less than the reference distance. Thus, from time T2 when the battery 3 is fully charged to time T3 when the engine stops, charging of the battery 3 (rapid charging) and stopping of the charging operation due to full charging are alternately repeated. As a result, before the engine is stopped at time T3, the battery 3 is quickly set to almost full charge, and this state is maintained until the time of engine stop at time T3.

  When the engine is stopped at time T3, charging of the battery 3 is stopped, and then the battery 3 is discharged by dark current or the like flowing in the automobile. For this reason, after time T3, the output voltage of the battery 3 gradually decreases.

  Here, considering a comparative example (dotted line G2 in FIG. 2) in which the central control unit 13 does not perform control based on determination of the predicted travel distance, in this case, the battery 3 is rapidly charged even at time T1. Therefore, the output voltage of the battery 3 is likely to be about 12V before that. This state is maintained even at time T3 when the engine is stopped. Therefore, when the engine is stopped at time T3 and charging to the battery 3 is stopped, the output voltage of the battery 3 starts to drop from the 12V state, and at time T4, the output voltage of the battery 3 is about 8V. Will fall to. Since 8V is the minimum voltage required to start the engine next time, if the car is left without starting the engine after time T4, the output voltage of the battery 3 further decreases. Therefore, the next time the engine is started, the engine cannot be started due to insufficient voltage.

  On the other hand, in this embodiment, the predicted travel distance from the current location to the destination is detected by the car navigation device 1, and the battery 3 is rapidly charged at the time T1 when the predicted travel distance becomes less than a predetermined reference distance. Thus, the battery 3 can be fully charged by the time the engine is stopped (time T3), and then the output voltage of the battery 3 gradually decreases due to dark current or the like. However, it is possible to prevent a situation where the output voltage of the battery 3 is lower than the voltage necessary for starting the engine at least at the time T4.

  In the above embodiment, the vehicle has reached a predetermined range around the destination when it is determined that the predicted travel distance from the current location to the destination given from the car navigation device 1 is less than the reference distance. Although the supply level of the power supply to the battery 3 has been increased, information on the predicted travel time from the current location to the destination given from the car navigation device 1 is obtained, and this predicted travel time becomes less than the reference time. When it is determined that the vehicle has reached the predetermined range around the destination, the supply level of the power supply to the battery 3 may be increased.

1 is a block diagram illustrating a battery management device according to an embodiment of the present invention. It is a figure which shows transition of the output voltage of the battery to which the battery management apparatus of FIG. 1 was applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Car navigation apparatus 3 Battery 5 IG switch 7 Voltage sensor 9 Alternator 11 Engine control part 13 Central control part 21 Input device 23 Destination memory | storage part 25 Current position detection part 27 Recommended route search part 29 Travel prediction distance calculation part 31 Generator 31a Stator coil 31b Rotor coil 33 Regulator 35 Control unit

Claims (8)

A battery management device for managing a state of a battery mounted on a vehicle,
Power generation means for generating power based on engine power and supplying power to the battery;
A guessing means for guessing whether the vehicle has reached a predetermined range around the destination;
Control means for controlling the power generation means to increase the supply level of the power supply to the battery when the estimation means estimates that the vehicle has reached a predetermined range around the destination. Battery management device. The battery management device according to claim 1,
The inference means is that the vehicle has reached a predetermined range around the destination when the predicted travel distance from the current location of the vehicle to the destination given from the car navigation device is less than a predetermined reference distance. A battery management device characterized by guessing. The battery management device according to claim 1,
When the estimation means determines that the vehicle has reached a predetermined range around the destination when the estimated travel time from the current location of the vehicle to the destination given by the car navigation device is less than a predetermined reference time. A battery management device characterized by guessing. The battery management device according to any one of claims 1 to 3,
Battery state detection means for detecting the state of the battery,
The battery management apparatus, wherein the control means controls the power generation means so as to temporarily stop the charging of the battery when the battery state detection means detects a full charge of the battery. A battery management method for managing a state of a battery mounted on a vehicle,
A first step of estimating whether or not the vehicle has reached a predetermined range around the destination by a predetermined estimation means;
A battery management method comprising: a second step of increasing a supply level of the power supply to the battery when it is estimated that the vehicle has reached a predetermined range around the destination in the first step. The battery management method according to claim 5,
When the estimation means is a car navigation device and the predicted travel distance between the current location of the vehicle and the destination is less than a predetermined reference distance, it is estimated that the vehicle has reached a predetermined range around the destination The battery management method characterized by the above-mentioned. The battery management method according to claim 5,
When the estimation means is a car navigation device, and the estimated travel time to the current location of the vehicle and the destination is less than a predetermined reference time, it is estimated that the vehicle has reached a predetermined range around the destination The battery management method characterized by the above-mentioned. A battery management method according to any one of claims 5 to 7,
And further comprising a third step of detecting the state of the battery,
A battery management method comprising: temporarily stopping charging of the battery in the second step when full charging of the battery is detected in the third step.

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