JP2014187731A - Power supply unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply unit which makes possible to suppress the degradation of the performance of a battery which is charged by a power generated by an on-vehicle power generator and supplies a power to a group of electric loads while the battery is stored over a long term, and to reduce a fuel consumption.SOLUTION: A power supply unit comprises: an alternator 3; a lithium storage battery 1 which is charged by a power generated by the alternator 3, and supplies a power to an electric load 4; a lead storage battery 2 which is charged by a power generated by the alternator 3, and supplies a power to a starter 5 for starting an engine; and a control part 7 which senses a power storage amount (SOC) on the basis of an output voltage value and a current value of the lithium storage battery 1 detected by a voltage detector 71 and a current detector 73. When having received a signal showing the stop of an engine through an input/output part 75 from an IG switch 81, the control part 7 performs control for charging the lithium storage battery 1 from the lead storage battery 2 on condition that the power storage amount of the lithium storage battery 1 is equal to or lower than a lower limit of a target SOC range during the time of storage.

Description

  The present invention relates to a power supply apparatus that includes a battery that is charged by electric power generated by an on-vehicle generator and supplies electric power to an electric load group.

  Electric loads installed in vehicles tend to increase year by year. For example, the electric load is increased by adopting an electric brake, an electric power steering device, and the like in order to improve the control performance and efficiency by electrifying equipment that has been operated by hydraulic pressure or engine power. In addition, in order to improve the fuel consumption efficiency in the engine, the electric load tends to increase also by adopting an electric motor that assists the engine output, a starter motor for restarting after idling stop, and the like.

  In response to such an increase in electrical load, in addition to the conventional lead storage battery in a vehicle, a lithium ion storage battery (hereinafter referred to as a lithium storage battery) is provided, and the power generated by the in-vehicle generator is used as a lead storage battery and a lithium storage battery. Power supply devices that are supplied to and charged and discharged have been developed. Lithium storage batteries can be charged and discharged at a higher voltage than lead storage batteries, generally have better charging efficiency than lead storage batteries, and are suitable for improving fuel consumption efficiency. In such a power supply device, for example, a method of switching the connection state to the load in accordance with the output voltages of the lead storage battery and the lithium storage battery has been devised regarding the usage method of the two batteries (for example, Patent Document 1). ).

  On the other hand, a device has been devised for suppressing the deterioration of the battery performance in the power supply device and withstanding long-term use. For example, Patent Document 2 discloses that a first control unit that determines a usage range of a storage amount of a battery, a detector that detects a storage amount of the battery, and a battery that is within the determined usage range of the storage amount. The conventional power supply device provided with the 2nd control part which controls charging / discharging is disclosed. This conventional power supply device lowers the upper limit value of the range of use of the amount of electricity determined by the first control unit when the vehicle is approaching long-term parking. The vehicle is left for a long period of time while the battery is fully charged or nearly full, that is, the state of charge (SOC) representing the ratio of the current charged amount to the full charged amount remains in a high SOC state. It is known that the battery capacity is likely to deteriorate and the battery life is shortened. As described above, the conventional power supply device predicts long-term parking and lowers the upper limit of the usage range of the amount of stored electricity, thereby preventing the battery from being left for a long time in a high SOC state, thereby reducing the performance of the battery. It is intended to withstand long-term use.

JP 2011-176958 A JP 2009-001049 A

  However, although the power supply device described in Patent Document 1 is provided with a plurality of batteries such as a lead storage battery and a lithium storage battery, it can cope with an increase in electric load. It has not been. Further, although Patent Document 2 prevents the battery from being left for a long time in a high SOC state, long-time leaving in a low SOC state also causes deterioration of battery performance. Therefore, control for suppressing deterioration on the low SOC side is required.

  Furthermore, in patent document 2, since long-term parking is predicted, the upper limit value of the usage range of the amount of stored electricity is reduced. Therefore, when the current SOC exceeds the upper limit value of the reduced usage range, the on-vehicle generator Since the electric power generated by the battery is discarded without being charged in the battery, there is a problem that it is not suitable for improving fuel consumption.

  The present invention has been made in view of such circumstances, and can be prevented from deterioration of battery performance during long-term storage of a battery that is charged by the generated power of the on-vehicle generator and supplies power to the electric load group, Furthermore, it aims at providing the power supply device which can reduce fuel consumption.

  A power supply device according to the present invention includes an on-vehicle generator that generates power in conjunction with an engine mounted on a vehicle, a first battery that is charged with electric power generated by the on-vehicle generator and supplies electric power to an electric load group, In a power supply device comprising a second battery that is charged with electric power generated by the in-vehicle generator and supplies electric power to a starter that starts the engine, an acquisition unit that acquires a signal indicating operation and stop of the engine; When the detection unit for detecting the storage amount of the first battery and the signal indicating the stop by the acquisition unit are acquired, when the storage amount detected by the detection unit is equal to or less than a predetermined amount, the second battery And a control means for performing control for charging one battery.

  In the present invention, the on-vehicle generator generates power in conjunction with the engine mounted on the vehicle, and the first battery is charged with the electric power generated by the on-vehicle generator and supplies the electric load group with electric power. The second battery is charged with electric power generated by the on-vehicle generator and supplies electric power to a starter that starts the engine. When the acquisition unit acquires a signal indicating the operation and stop of the engine, the detection unit detects the storage amount of the first battery, and the acquisition unit acquires the signal indicating stop, the amount of storage detected by the detection unit is When it is below the fixed amount, the control means performs control to charge the first battery from the second battery. Thereby, a 1st battery is charged and deterioration of the battery performance at the time of long-term storage can be suppressed.

  The power supply device according to the present invention includes second acquisition means for acquiring the position of the vehicle from a position detection device that detects the position of the vehicle, and the control means is configured such that the position acquired by the second acquisition means is a specific location. In this case, the second battery is controlled to be charged from the second battery.

  In the present invention, the position of the vehicle is acquired by the second acquisition means from the position detection device that detects the position of the vehicle, and the control means is configured such that when the position acquired by the second acquisition means indicates a specific place, Control to charge the first battery from the two batteries is performed. Thereby, for example, by setting a specific place such as a home or work place, it can be reliably detected that the first battery is in a long-term storage state.

  In the power supply device according to the present invention, when the position acquired by the second acquisition unit is within a certain distance from a specific location, the on-vehicle power generation is performed when the storage amount detected by the detection unit is a predetermined amount or less. And a second control means for performing control for charging the first battery from a machine.

  In the present invention, when the position acquired by the second acquisition means is within a certain distance from the specific location, the second control means mounts the vehicle on the vehicle when the storage amount detected by the detection means is less than or equal to a predetermined amount. Control is performed to charge the first battery from the generator. Thereby, the electric power generated by the in-vehicle generator can be used effectively, and fuel consumption is reduced.

  The power supply device according to the present invention includes a second detection unit that detects a storage amount of the second battery, and a calculation unit that calculates a difference between the second predetermined amount and the storage amount detected by the second detection unit. The second control unit is characterized in that the first battery is charged until the amount of electricity stored is obtained by adding the difference to the third predetermined amount related to the first battery.

  In the present invention, the storage amount of the second battery is detected by the second detection means, and the difference between the second predetermined amount and the storage amount detected by the second detection means is calculated by the calculation means. The second control means charges the first battery until the amount of power storage is obtained by adding the difference to the third predetermined amount related to the first battery. As a result, a large amount of electric power can be stored in the first battery and charged from the first battery to the second battery, and the electric power can be used more effectively.

  The power supply device according to the present invention includes third acquisition means for acquiring a signal indicating that a portable wireless device that communicates wirelessly with a communication device arranged in the vehicle does not exist within a communication range of the communication device, The control means performs control for charging the second battery from the second battery when the signal indicating that the third acquisition means does not exist is acquired.

  In the present invention, the third acquisition unit acquires a signal indicating that a portable wireless device that communicates wirelessly with a communication device arranged in a vehicle does not exist within the communication range of the communication device, and the control unit includes: When the signal indicating that the third acquisition unit does not exist is acquired, control is performed to charge the second battery from the second battery. Thereby, it can detect reliably that a 1st battery will be in a long-term storage state.

  In the power supply device according to the present invention, the first battery is a lithium ion storage battery or a nickel hydride storage battery, and the second battery is a lead storage battery.

  In the present invention, the first battery is a lithium ion storage battery or a nickel hydride storage battery, and the second battery is a lead storage battery. Thereby, deterioration of the battery performance at the time of long-term storage of a lithium ion storage battery or a nickel metal hydride storage battery can be suppressed.

  According to the present invention, the on-vehicle generator generates power in conjunction with the engine mounted on the vehicle, and the first battery is charged with the electric power generated by the on-vehicle generator, and supplies the electric load group with electric power. The second battery is charged with electric power generated by the on-vehicle generator and supplies electric power to a starter that starts the engine. When the acquisition unit acquires a signal indicating the operation and stop of the engine, the detection unit detects the storage amount of the first battery, and the acquisition unit acquires the signal indicating stop, the amount of storage detected by the detection unit is When it is below the fixed amount, the control means performs control to charge the first battery from the second battery. For this reason, a 1st battery is charged and the deterioration of the battery performance at the time of long-term storage can be suppressed.

It is a block diagram which shows schematic structure of the power supply device which concerns on embodiment of this invention. It is a graph which shows the time transition of SOC of a lithium storage battery. It is a schematic diagram for demonstrating the chargeable electric power of a lead storage battery. It is a flowchart which shows the process sequence of the charge control based on the long-term parking prediction by a control part. It is a flowchart which shows the process sequence of long-term parking prediction. It is a flowchart which shows the process sequence of the charge control after long-term parking.

  Hereinafter, the present invention will be described with reference to the drawings illustrating embodiments thereof. FIG. 1 is a block diagram showing a schematic configuration of a power supply device 10 according to an embodiment of the present invention. The power supply device 10 is mounted on a vehicle 100, and includes a lithium storage battery 1, a lead storage battery 2, an alternator 3 (abbreviated as ALT3 in FIG. 1), a DC / DC converter 6 (abbreviated as DC / DC6 in FIG. 1), An electric load 4 (abbreviated as load 4 in FIG. 1) and a starter 5 (abbreviated as ST5 in FIG. 1) such as an electric brake, an electric power steering device, an auxiliary electric motor and a restart starter. To supply power. The alternator 3 is a generator connected to an engine (not shown) that is a driving power source of the vehicle 100 and generates electric power by rotation of an engine output shaft. The DC power generated and rectified by the alternator 3 is supplied to a lithium storage battery 1, a lead storage battery 2 and an electric load 4 connected in parallel. The alternator 3 performs regenerative control to generate power when the vehicle 100 is decelerating, thereby providing a load to the rotation of the engine output shaft and applying braking force to the vehicle 100, and charging each battery with the generated power. Electric power is supplied to the electric load 4.

  The starter 5 rotates the crankshaft of an engine (not shown), and starts the engine by igniting fuel with an ignition device. The starter 5 operates mainly by receiving power supply from the lead storage battery 2, but when the SOC of the lead storage battery 2 at the time of engine start is low, the lithium storage battery 1 is connected in parallel to the lead storage battery 2, and the lithium storage battery 1 and lead Power can be supplied from the storage battery 2 to the starter 5 for operation. The alternator 3 functions as an on-vehicle generator in the present invention.

  The lithium storage battery 1 is connected to the electric load 4 via the alternator 3 and the DC / DC converter 6, and is charged by the alternator 3 and discharged to the electric load 4. The lithium storage battery 1 is controlled in a SOC range (hereinafter referred to as a target SOC range) that is a control target during use in which charging / discharging is performed, for example, when the SOC is controlled within a range of 30% to 80%. The battery performance can be prevented from deteriorating and can be used for a long time. Moreover, since the lithium storage battery 1 generally has better charging efficiency than the lead storage battery 2, the electric load 4 is operated by mainly supplying power from the lithium storage battery 1, whereby the alternator 3 serving as the engine load is used. It is considered that power generation is suppressed and the fuel consumption of the vehicle 100 is improved. In order to supply power from the lithium storage battery 1 to the electric load 4, the output voltage of the lithium storage battery 1 may be set to be higher than the output voltage of the lead storage battery 2 at the output terminal of the lead storage battery 2. The lithium storage battery 1 functions as the first battery in the present invention.

  On the other hand, when the vehicle 100 is parked for a long time, the lithium storage battery 1 is not charged by the alternator 3 and discharged to the electric load 4. In order to be stored in a state where charging / discharging is not performed and the deterioration of the battery performance is suppressed to enable long-term use, the SOC of the lithium storage battery 1 is controlled within a target SOC range during long-term parking. The target SOC range at the time of long-term parking is generally narrower than the target SOC range at the time of use. For example, the SOC is in a range from 70% to 80%.

  The lead storage battery 2 is a storage battery that is widely installed in the vehicle 100, and for example, charging and discharging are controlled within a range of 12.7V to 12.8V (for example, 88% to 92% in terms of SOC) at the output terminal. As a result, the service life can be extended. The output terminal of the lead storage battery 2 is connected to the starter 5 and is operated by supplying power to the starter 5 when the engine is started. The output terminal of the lead storage battery 2 is connected to the lithium storage battery 1 and the alternator 3 via the DC / DC converter 6. The lead storage battery 2 is charged by being supplied with electric power from the alternator 3 via the DC / DC converter 6. The lead storage battery 2 functions as the second battery in the present invention.

  The DC / DC converter 6 is composed of, for example, a chopper and a coil, and is interposed between the output terminals of the lithium storage battery 1 and the lead storage battery 2, and boosts the voltage from one to the other between the output terminals. Conversely, the voltage is stepped down from the other side. As described above, the lithium storage battery 1 can be charged and discharged at a higher voltage than the lead storage battery 2 and contributes to the improvement of fuel consumption efficiency, so that the output terminal of the lithium storage battery 1 has a high potential. It is preferable to control charging / discharging. When the output terminal of the lithium storage battery 1 has a higher potential than the output terminal of the lead storage battery 2, the DC / DC converter 6 is configured to step down from the output terminal side of the lithium storage battery 1 toward the output terminal side of the lead storage battery 2. Controlled.

  Further, by supplying electric power from the lithium storage battery 1 to the electric load 4, the stored amount of the lithium storage battery 1 is reduced, and accordingly, the potential of the output terminal of the lithium storage battery 1 is decreased. Even when the potential of the output terminal of the lithium storage battery 1 is lower than the potential of the output terminal of the lead storage battery 2, the DC / DC converter increases the voltage from the output terminal side of the lithium storage battery 1 toward the output terminal side of the lead storage battery 2. 6, the potential on the lithium storage battery 1 side at the output terminal of the lead storage battery 2 can be set high, and power can be supplied from the lithium storage battery 1 to the electric load 4.

  In addition, when charging the lithium storage battery 1 from the lead storage battery 2, the output terminal side of the lead storage battery 2 is changed from the output terminal side of the lead storage battery 2 to the output terminal side of the lithium storage battery 1 in order to increase the potential of the lead storage battery 2 side at the output terminal of the lithium storage battery 1. The DC / DC converter 6 is controlled so as to step up the voltage. The control unit 7 performs step-up / step-down switching control of the DC / DC converter 6 and output voltage / current control of the DC / DC converter 6.

  The control unit 7 includes a CPU (Central Processing Unit) (not shown), a flash memory, a ROM using an EEPROM (Erasable Programmable Read Only Memory), an EEPROM (Electrically EPROM), and a DRAM (Dynamic Random Access Memory). And a RAM using a memory such as SRAM (Static Random Access Memory), and the control program stored in the ROM is executed by the CPU to control the DC / DC converter 6 and the like. The CPU temporarily stores data generated during the execution of the control program in the RAM. The control unit 7 is connected to an ignition switch (hereinafter referred to as IG switch) 81, a navigation device 82, a wireless key control device 83, and the like via a signal line or a communication network in the vehicle 100 by the input / output unit 75. Data necessary for control is acquired from these devices. The input / output unit 75 includes, for example, a data buffer, a communication control circuit (not shown) according to a network standard, and the like, and sends data output from the control unit 7 to a signal line or a communication network. The input data is sent to the control unit 7.

  In addition, voltage detectors 71 and 72 and current detectors 73 and 74 are connected to the control unit 7. The voltage detector 71 detects the output voltage value of the lithium storage battery 1, and the voltage detector 72 detects the output voltage value of the lead storage battery 2. The current detector 73 detects the amount of current input / output to / from the lithium storage battery 1, and the current detector 74 detects the amount of current input / output to / from the lead storage battery 2. The control unit 7 estimates the storage amount of the lithium storage battery 1 based on the output voltage value of the lithium storage battery 1 input from the voltage detector 71 and the amount of current input to and output from the lithium storage battery 1 input from the current detector 73. To do. In addition, the control unit 7 stores the storage amount of the lead storage battery 2 based on the output voltage value of the lead storage battery 2 input from the voltage detector 72 and the amount of current input to and output from the lead storage battery 2 input from the current detector 74. Is estimated. Furthermore, the charged amount may be detected by another method.

  The control unit 7 performs control based on the detected power storage amount. However, the detected power storage amount may be used for control as it is, or the power storage amount may be expressed as SOC and used for control. In the embodiment related to the control by the control unit 7 described below, an example in which the amount of stored electricity is represented by SOC will be described. The control unit 7 functions as a control unit, a second control unit, a detection unit, and a second detection unit in the present invention. The detection unit and the second detection unit may be configured separately from the control unit 7 in hardware. The input / output unit 75 functions as first, second, and third acquisition means in the present invention. The first, second, and third acquisition means may be integrated in hardware or separate.

  The control unit 7 performs long-term parking prediction processing for predicting whether the vehicle 100 will be parked for a long time based on data acquired from the IG switch 81, the navigation device 82, and the wireless key control device 83. The control unit 7 performs step-up / step-down switching control, output voltage control, and the like for the DC / DC converter 6 based on the SOC detected for the lithium storage battery 1 and the lead storage battery 2 based on the long-term parking prediction process. Do. Further, the control unit 7 switches the step-up / step-down operation with respect to the DC / DC converter 6 based on each output voltage detected by the voltage detectors 71 and 72 in order to supply electric power from the lithium storage battery 1 to the electric load 4. Control and output voltage control are performed.

  Next, the IG switch 81, the navigation device 82, and the wireless key control device 83 will be described. The IG switch 81 is a push button switch or the like that starts the engine when the driver presses the button. The IG switch 81 is permitted to be switched when the wireless key 84 is authorized by an authentication process based on identification information performed between the wireless key control device 83 and the wireless key 84 as described later. The IG switch 81 is gradually switched to an OFF position, an accessory position (hereinafter referred to as an ACC position), an ON position, and an engine start position by a user's pressing operation (including a long pressing operation). Outputs data indicating the position. Note that the position here is not a physical position but a functional state.

  In general, a lighting device (not shown) such as a headlight can be operated in the off position, and the navigation device 82 can be operated in the ACC position. In this way, only some of the in-vehicle devices with low power consumption can operate at the off position and the ACC position. On the other hand, in the on position, in addition to the window opening and closing device and the air conditioner, many on-vehicle devices such as a turn lamp, a wiper, and a meter device (not shown) can operate. Further, the starter 5 operates at the engine start position, the fuel is ignited by the ignition device, the engine is started, and the engine is returned to the on position after the engine is started. When the IG switch 81 is operated from the on position after the engine is started to the ACC position or the off position, the engine shifts from the operating state to the stopped state. The control unit 7 acquires the data output from the IG switch 81 via the input / output unit 75, and the engine is stopped when the IG switch 81 is switched from the on position to the off position or the ACC position based on the data. It is determined that

  The navigation device 82 receives radio waves for positioning provided by GPS (Global Positioning System), measures the current position of the vehicle 100, and displays the measured current position together with map information on the display. The navigation device 82 has a map information database and can designate a specific place. For example, in a state where map information is displayed on a display that accepts a touch operation, a specific place such as a home or work place that is likely to be parked for a long time is touch-input, or an address of the specific place is specified by key input. Record location information. The navigation device 82 outputs the position information of the vehicle 100 and the position information of the specified specific place. The control unit 7 acquires the data output from the navigation device 82 via the input / output unit 75, and performs long-term parking prediction processing based on the data. The navigation device 82 functions as a position detection device in the present invention.

  The wireless key control device 83 locks and unlocks the door of the vehicle 100 when the wireless key 84 is authorized by an authentication process based on identification information performed with the wireless key 84. When the wireless key control device 83 transmits a calling signal for calling the wireless key 84 and does not receive a response signal to be transmitted from the wireless key 84 in response to the calling signal, the wireless key 84 is within the communication range. Judge that there is no. The communication range of the wireless key control device 83 is, for example, a range of several meters inside and outside the vehicle 100. The wireless key control device 83 outputs data indicating whether the wireless key 84 is within the communication range. The control unit 7 acquires the data output from the wireless key control device 83 via the input / output unit 75, and performs long-term parking prediction processing based on the data. The wireless key control device 83 functions as a communication device according to the present invention, and the wireless key functions as a portable wireless device according to the present invention.

  Next, the battery charging control operation based on the long-term parking prediction process by the control unit 7 will be described. FIG. 2 is a graph showing the time transition of the SOC of the lithium storage battery 1, and FIG. 3 is a schematic diagram for explaining the chargeable power of the lead storage battery 2. By approaching a specific place where there is a possibility of long-term parking, such as at home or work place, at time t1, the control unit 7 detects long-term parking prediction. After the long-term parking prediction is detected, when the regenerative power generated by the alternator 3 is greater than the power consumption of the electric load 4, the lithium storage battery 1 is charged and the time transition is made along the route A shown in FIG. To do.

  The amount of power stored in the lithium storage battery 1 is originally within the range of the target SOC (for example, 70% to 80%) at the time of storage, but the upper limit value is increased in consideration of charging the lead storage battery 2 later. . As shown in FIG. 3, the difference between the upper limit SOC (92%) in the target SOC range of the lead storage battery 2 and the current SOC is the chargeable power to the lead storage battery 2. The control unit 7 obtains an expanded SOC upper limit value obtained by adding the chargeable power to the lead storage battery 2 to the upper limit SOC in the target SOC at the time of storage of the lithium storage battery 1, and the storage amount of the lithium storage battery 1 becomes the expanded SOC upper limit value. Continue charging. The control unit 7 stops the charging of the lithium storage battery 1 at time t2 when the stored amount of the lithium storage battery 1 reaches the expanded SOC upper limit value. To stop charging the lithium storage battery 1, the regeneration of the alternator 3 may be stopped or the connection with the lithium storage battery 1 may be cut off.

  At time t4, the control unit 7 determines that the engine has been stopped based on the data from the IG switch 81, and determines that the state is that long-term parking has started. After determining that the engine is stopped, the control unit 7 further determines whether or not the wireless key 84 is within the communication range based on the data from the wireless key control device 83, and if the wireless key 84 is not within the communication range. When the determination is made, it may be determined that long-term parking has started. Thereafter, the controller 7 charges the lead storage battery 2 from the lithium storage battery 1 during the period from time t5 to t6, and the SOC of the lithium storage battery 1 after charging is set within the target SOC during storage. When charging the lead storage battery 2 from the lithium storage battery 1, the control unit 7 controls the DC / DC converter 6 at the output terminal of the lead storage battery 2 so that the potential on the lithium storage battery 1 side becomes high. In consideration of using the lithium storage battery 1 on the higher voltage side than the lead storage battery 2, the control unit 7 controls the DC / DC converter 6 so as to step down from the output terminal of the lithium storage battery 1 toward the output terminal of the lead storage battery 2. Control may be performed, and if the potential difference is small, control may be performed so as to connect without performing step-up / step-down.

  On the other hand, after the long-term parking prediction is detected at time t1, the regenerative power of the alternator 3 does not increase, for example, because the vehicle 100 travels at a low speed, and the power consumption of the lithium storage battery 1 by the electric load 4 has advanced. In this case, the time changes along the route B shown in FIG. At time t3, power consumption by the electric load 4 disappears, and then the control unit 7 determines that the long-term parking has started as described above at time t4. Thereafter, the control unit 7 charges the lithium storage battery 1 from the lead storage battery 2 during the period from time t5 to time t6, and the SOC of the lithium storage battery 1 after charging is set within the target SOC during storage. When charging from the lead storage battery 2 to the lithium storage battery 1, the control unit 7 controls the DC / DC converter 6 at the output terminal of the lithium storage battery 1 so that the potential on the lead storage battery 2 side becomes high. Specifically, the control unit 7 controls the DC / DC converter 6 so as to increase the voltage from the output terminal of the lead storage battery 2 toward the output terminal of the lithium storage battery 1.

  Next, a charging control processing procedure based on long-term parking prediction by the control unit 7 will be described. 4 is a flowchart showing a charging control processing procedure based on long-term parking prediction by the control unit 7, FIG. 5 is a flowchart showing a long-term parking prediction processing procedure, and FIG. 6 is a charging control processing procedure after long-term parking. It is a flowchart which shows. In the flowchart shown in FIG. 4, the control unit 7 performs long-term parking prediction processing (step S1). The control unit 7 starts the long-term parking prediction process shown in FIG. 5 and acquires the current position of the vehicle 100 from the navigation device 82 via the input / output unit 75 in step S11. The control unit 7 obtains the specific location from the navigation device 82 in advance, and calculates the distance between the current position of the vehicle 100 and the specific location in step S12. The controller 7 determines whether or not the vehicle 100 is located within a certain distance range from the specific location in step S13. The fixed distance may be set to a value that is large to some extent so that the lithium storage battery 1 can be sufficiently charged. However, if the fixed distance is set to a large value, the accuracy of long-term parking prediction may decrease. It also depends on the normal operation mode of the vehicle 100. For example, a distance of about one-tenth of the average distance traveled in one operation may be set as a fixed distance, and the operation mode of the vehicle 100 that reciprocates between the home and the workplace is almost the case. The accuracy of long-term parking prediction is high.

  If it is determined that the distance is within the certain distance range (S13: YES), it is further determined in step S14 whether or not the vehicle 100 is approaching a specific place. Here, that the vehicle 100 is approaching a specific place means that the vehicle 100 is moving so as to approach the specific place. Whether or not the vehicle 100 is approaching the specific location can be determined by the distance between the current position of the vehicle 100 and the specific location calculated over a plurality of times in time series. When it is determined that the vehicle is approaching the specific place (S14: YES), the control unit 7 temporarily stores the value of the prediction flag as “1” in the control unit 7 in step S15. On the other hand, when it is determined that it is not within the certain distance range (S13: NO) and when it is determined that it is not approaching the specific place (S14: NO), the control unit 7 sets the prediction flag in step S16. The value is temporarily stored in the control unit 7 as “0”. After steps S15 and S16, the controller 7 finishes the long-term parking prediction process.

  After the long-term parking prediction process in step S1 shown in FIG. 4, the control unit 7 determines whether there is a long-term parking prediction in step S2 based on the value of the prediction flag temporarily stored in the control unit 7. When the value of the prediction flag is “0” and there is no prediction of long-term parking (S2: NO), the control unit 7 returns to step S1 and performs long-term parking prediction processing. When the value of the prediction flag is “1” and long-term parking is predicted (S2: YES), the control unit 7 detects the current SOCs of the lithium storage battery 1 and the lead storage battery 2 in step S3, and step S4. Thus, the chargeable power of the lead storage battery 2 is calculated. Moreover, the control part 7 adds chargeable electric power to the upper limit in the target SOC range at the time of storage of the lithium storage battery 1, and calculates an expansion SOC upper limit by step S5.

  The controller 7 determines whether or not the alternator 3 is regenerating in step S6. It is assumed that the information on whether or not regeneration is already known in the regeneration control process for the alternator 3. When it determines with regeneration (S6: YES), the control part 7 determines further whether SOC of the lithium storage battery 1 is more than an expansion SOC upper limit by step S7. When it is determined that the SOC of the lithium storage battery 1 is equal to or greater than the expanded SOC upper limit value (S7: YES), the control unit 7 stops charging the lithium storage battery 1 in step S8, and returns to step S1. Moreover, when it determines with SOC of the lithium storage battery 1 being less than expansion SOC upper limit (S7: NO), the control part 7 continues charge to the lithium storage battery 1 by step S9, and returns to step S1.

  If it is determined in step S6 that the engine is not regenerated (S6: NO), as shown in FIG. 6, the control unit 7 determines whether the engine is stopped in step S21 based on the data from the IG switch 81. To do. When it is determined that the engine is not stopped (S21: NO), the control unit 7 returns the process to step S1 shown in FIG. When it is determined that the engine is stopped (S21: YES), the control unit 7 determines whether or not the SOC of the lithium storage battery is less than the lower limit value in the target SOC range at the time of storage in step S22. When it determines with it being less than a lower limit (S22: YES), the control part 7 charges the lithium storage battery 1 from the lead storage battery 2 by controlling the DC / DC converter 6 by step S23. On the other hand, when it determines with it not being less than a lower limit (S22: NO), the control part 7 determines whether SOC of a lithium storage battery is larger than the upper limit in the target SOC range at the time of storage by step S24. . When it determines with it being larger than an upper limit (S24: YES), the control part 7 charges the lead storage battery 2 from the lithium storage battery 1 by controlling the DC / DC converter 6 by step S25. Control part 7 judges whether SOC of lithium storage battery 1 is in the target SOC range at the time of storage by Step S26 after Steps S23 and S25. When it determines with it not being in the target SOC range at the time of storage (S26: NO), the control part 7 returns a process to step S22. When it determines with it being in the target SOC range at the time of storage (S26: YES) and when it determines with it being smaller than an upper limit (S24: NO), the control part 7 complete | finishes a process.

  As described above, according to the present embodiment, the alternator 3 generates power in conjunction with the engine mounted on the vehicle 100, and the lithium storage battery 1 is charged by the power generated by the alternator 3 and supplies the electric load 4 with power. The lead storage battery 2 is charged by the electric power generated by the alternator 3 and supplies electric power to the starter 5 that starts the engine. A signal indicating the operation and stop of the engine is acquired from the IG switch 81 by the input / output unit 75. The control unit 7 detects the storage amount (SOC) based on the output voltage value of the lithium storage battery 1 detected by the voltage detector 71. When the signal indicating the stop is acquired by the input / output unit 75, when the storage amount of the lithium storage battery 1 is equal to or less than the lower limit in the target SOC range during storage as a predetermined amount, the control unit 7 Control to charge the storage battery 1 is performed. Thereby, it charges so that the electrical storage amount of the lithium storage battery 1 may become more than the lower limit in the target SOC range at the time of storage, and it can suppress deterioration of the battery performance at the time of long-term storage.

  Further, the position of the vehicle 100 is acquired from the navigation device 82 by the input / output unit 75, and the control unit 7 performs control to charge the lithium storage battery 1 from the lead storage battery 2 when the position of the vehicle 100 indicates a specific place. It may be. Thereby, for example, by setting a specific place such as a home or work place, it is possible to reliably detect that the lithium storage battery 1 is in a long-term storage state.

  According to the present embodiment, when the position of the vehicle 100 acquired from the navigation device 82 by the input / output unit 75 is within a certain distance from the specific location, the stored amount of the lithium storage battery 1 is equal to or less than a predetermined amount. The control unit 7 performs control for charging the lithium storage battery 1 from the alternator 3. Thereby, the electric power generated by the alternator 3 can be used effectively, and fuel consumption is reduced.

  Further, according to the present embodiment, the control unit 7 detects the amount of charge (SOC) based on the output voltage value of the lead storage battery 2 detected by the voltage detector 72. The control unit 7 calculates a difference (chargeable power) between the upper limit value in the target SOC range of the lead storage battery 2 as the second predetermined amount and the detected storage amount of the lead storage battery 2. The control unit 7 charges the lithium storage battery 1 until the storage amount is obtained by adding the chargeable power to the upper limit value (third predetermined amount) in the target SOC range when the lithium storage battery 1 is stored. Thereby, big electric power can be stored by the lithium storage battery 1, the lithium storage battery 1 can be charged to the lead storage battery 2, and electric power can be used more effectively.

  Further, according to the present embodiment, the input / output unit 75 acquires a signal indicating that the wireless key 84 does not exist within the communication range of the wireless key control device 83, and the control unit 7 determines that the wireless key 84 is within the communication range. When a signal indicating that it does not exist is acquired, control is performed to charge the lithium storage battery 1 from the lead storage battery 2. Thereby, it can detect reliably that the lithium storage battery 1 will be in a long-term storage state.

  Although the lithium storage battery 1 is used in the above-described embodiment, a nickel hydride storage battery may be used instead of the lithium storage battery 1. In this case, it is possible to suppress deterioration in battery performance during long-term storage of the nickel-metal hydride storage battery.

  As mentioned above, although the form for inventing was demonstrated, it should be thought that disclosed embodiment is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 Lithium storage battery (first battery)
2 Lead acid battery (second battery)
3 Alternator (on-vehicle generator)
4 Electric load (electric load group)
5 starter 6 DC / DC converter 7 control unit (control means, second control means, detection means and second detection means)
75 Input / output unit (first, second and third acquisition means)
81 IG switch 82 Navigation device (position detection device)
83 Wireless key control device (communication device)
84 Wireless key (mobile radio)

Claims (6)

A vehicle-mounted generator that generates power in conjunction with an engine mounted on the vehicle, a first battery that is charged with power generated by the vehicle-mounted generator and supplies power to an electric load group, and power generated by the vehicle-mounted generator And a second battery for supplying power to a starter for starting the engine,
Obtaining means for obtaining a signal indicating operation and stop of the engine;
Detecting means for detecting a storage amount of the first battery;
Control means for controlling charging from the second battery to the first battery when the signal indicating stop is acquired by the acquisition means and the amount of charge detected by the detection means is a predetermined amount or less. A power supply device characterized by that. A second acquisition means for acquiring the position of the vehicle from a position detection device for detecting the position of the vehicle;
2. The control unit according to claim 1, wherein when the position acquired by the second acquisition unit indicates a specific place, the control unit performs control to charge the first battery from the second battery. The power supply described.   When the position acquired by the second acquisition means is within a certain distance from a specific location, the first battery is charged from the in-vehicle generator when the storage amount detected by the detection means is less than or equal to a predetermined amount. The power supply apparatus according to claim 2, further comprising second control means for performing control. Second detection means for detecting the amount of electricity stored in the second battery;
Calculating means for calculating a difference between the second predetermined amount and the amount of stored electricity detected by the second detecting means;
The said 2nd control means is charging the said 1st battery until it becomes the electrical storage amount which added the said difference to the 3rd predetermined amount which concerns on the said 1st battery, The Claim 3 characterized by the above-mentioned. Power supply. A third acquisition means for acquiring a signal indicating that a portable wireless device that communicates wirelessly with a communication device disposed in the vehicle does not exist within a communication range of the communication device;
The control means performs control to charge the first battery from the second battery when a signal indicating that the control means does not exist is acquired by the third acquisition means. The power supply device according to claim 1. The first battery is a lithium ion storage battery or a nickel hydride storage battery,
The power supply device according to claim 1, wherein the second battery is a lead storage battery.

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