JP5077702B2 - Charge control device - Google Patents

Description

  The present invention relates to a charge control device for a rechargeable battery.

  A vehicle such as an EV (Electric Vehicle) or a HEV (Hybrid Electric Vehicle) is equipped with a capacitor that supplies electric power to a motor or the like. A storage battery mounted on a vehicle is mounted with a storage battery such as a lithium ion battery or a nickel metal hydride battery.

  When using, for example, a lithium ion battery as a battery, the battery is deteriorated if the battery is left on the vehicle for a long time or is used for a long time. As shown in FIG. 12, the deterioration of the storage battery is standardized by the state of charge of the storage battery (SOC: State Of Charge, 100% and 0% when fully charged and fully discharged, respectively). It is easy to occur when the value is high. FIG. 12 is a diagram illustrating an example of the relationship between the endurance days (the number of days used) and the capacity reduction rate of the battery. That is, if the capacitor is used or left in a high SOC state, the capacity reduction rate increases, and the capacitor tends to deteriorate.

  Similarly, when the battery is in a high SOC state, the usable capacity decreases due to the capacity deterioration of the battery. The usable capacity is a difference between the upper limit SOC that can be used and the lower limit SOC that can be used. FIG. 13 is a diagram illustrating an example of the relationship between the years of use and the usable capacity of a conventional storage battery.

  As an example of a method for preventing such deterioration of the storage battery, in order to prevent the storage battery from being left at a high SOC, it is discharged using an externally connected device, or before using the vehicle using a timer. A technique for charging is known (see, for example, Patent Document 1). In addition, a technique is known in which a lithium ion secondary battery is discharged before being left for a long time in a charged state at a high temperature (see, for example, Patent Document 2).

JP 2002-199616 A JP 2000-287372 A

  However, in the techniques of Patent Documents 1 and 2, in order to avoid leaving in a high SOC state and obtain a desired amount of charge during use, charging and discharging of the battery must be repeated.

  In addition, the conventional battery is not particularly restricted from the usable lower limit SOC to the limit upper limit SOC as the usable SOC range from the initial use to the last stage. In such energy management that uses the usable SOC region throughout the storage device usage period, the vehicle may be left or used in a high SOC region from a relatively early stage of use. As a result, the deterioration of the storage battery progresses, and the ratio of the electric driving decreases, such as the reduction of the electric driving possible distance and the time for assisting and regenerating, which may give the user a sense of incongruity during the driving. Furthermore, the deterioration of the battery is promoted only by stopping, and the vehicle may not be able to travel due to the deterioration of the battery even if the travel distance is short.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a charge control device capable of charging while suppressing the progress of deterioration of a capacitor without performing unnecessary charging / discharging of the capacitor. And

In order to solve the above problems and achieve the object, a charge control device according to claim 1 is a charge control device for a chargeable battery (for example, battery 101 in the embodiment), A voltage detection unit (for example, a voltage sensor 133 in the embodiment) that detects a voltage of the battery, a current detection unit (for example, a current sensor 135 in the embodiment) that detects a charge / discharge current of the battery, and the voltage detection A storage capacity estimation unit (for example, battery ECU 123 in the embodiment) for estimating a storage capacity (for example, SOC in the embodiment) of the battery, and a current detection unit. A charge / discharge amount calculation unit (for example, the management ECU 117 in the embodiment) that calculates a charge / discharge amount from the start of charging of the battery by integrating the charge / discharge current. Serial based on the charge and discharge amount of the capacitor that is calculated by the storage capacity and the charging and discharging amount calculating portion of the capacitor that is estimated by the battery capacity estimation unit, so that the storage capacity of the storage battery falls below the actual use upper limit charge capacity the charge control unit controlling charging of the capacitor (e.g., management ECU117 in an embodiment) and an on, the charging control unit, when updating sets the actual use upper limit charge capacity, making the charging of the capacitor discharge amount calculated by the charge and discharge amount calculating unit upon reaching the predetermined value, and updates setting the storage capacity estimated by the battery capacity estimating unit to the actual use upper limit charge capacity in .

Further, the charging control apparatus of the invention described in claim 2, wherein the charging control unit, when updating sets the actual use upper limit charge capacity, which is estimated by the battery capacity estimation unit when performing charging of said capacitor when discharge amount calculated by the charge and discharge amount calculating unit from the time the electricity storable capacity can be lower storage capacity used has reached the predetermined value, the storage capacity estimated by the battery capacity estimation unit the real It is set to the use upper limit storage capacity.

Furthermore, in the charge control device according to claim 3, when the charge control unit updates and sets the actual use upper limit storage capacity, the storage capacity estimated by the storage capacity estimation unit is the actual use upper limit storage capacity. Control is performed so that the battery is charged until the charge / discharge amount calculated by the charge / discharge amount calculation unit reaches a predetermined value even when the capacity is reached.

  Furthermore, in the charge control device of the invention according to claim 4, the charge control unit is configured such that the storage capacity estimated by the storage capacity estimation unit does not reach the actual use upper limit storage capacity, but the charge / discharge amount is When the charge / discharge amount calculated by the calculation unit reaches a predetermined value, control is performed such that charging of the battery is stopped.

Furthermore, the charge control device of the invention described in claim 5 is a storage unit (for example, in the embodiment) that stores the storage capacity estimated by the storage capacity estimation unit each time the charge / discharge amount reaches a predetermined value. Storage unit), and when the charge control unit updates and sets the actual use upper limit storage capacity, the actual use upper limit storage capacity is set based on the storage capacity stored in the storage unit.

  Furthermore, the charge control device of the invention described in claim 6 is characterized in that the storage unit stores a predetermined number of storage capacities estimated each time the charge / discharge amount reaches the predetermined value.

  Furthermore, in the charge control device of the invention according to claim 7, the storage unit stores a predetermined number of storage capacities estimated each time the charge / discharge amount reaches the predetermined value for a predetermined time. It is characterized by.

Further, the charging control apparatus of the invention described in claim 8, wherein the charge control unit, the charging of the power storage capacity estimated by the battery capacity estimation unit at a greater state than can limit charge capacity used to the capacitor In the second charging mode, the actual use upper limit storage capacity, the usable lower limit storage capacity, and the storage capacity estimation unit are estimated in the second charge mode. The remaining amount of the capacitor at the start of charging is estimated based on the stored storage capacity and the predetermined value, and the charge control device includes the remaining amount as the charge / discharge amount when charging the capacitor. It is characterized by that.

  Furthermore, in the charging control device according to the ninth aspect of the present invention, the second charging mode is configured such that the power storage device includes an external power source outside the vehicle on which the power storage device is mounted (for example, the external power supply source 139 in the embodiment). When the battery is connected, the remaining amount is estimated by the storage capacity estimation unit when the actual use upper limit storage capacity is B, the usable lower limit storage capacity is C, and the storage capacity estimation unit when the battery is connected to the external power source. When the stored power storage capacity is X and the predetermined value is A, it is estimated as (X−C) / (B−C) × A.

Further, the charging control apparatus of the invention described in claim 10, when the limit the upper limit storage capacity has been initialized, the charge control unit, said practically Kiri蓄 capacity exceeds the limit the upper limit storage capacity In this case, it is presumed that a failure has occurred in the battery, and a notification unit is notified of this.

  According to the charge control device of the first aspect of the present invention, it is possible to charge the battery while suppressing the progress of deterioration of the battery without performing unnecessary charge / discharge of the battery. Furthermore, it is possible to set an actual use upper limit storage capacity capable of charging an optimum charge amount for the storage battery.

  According to the charge control device of the second aspect of the present invention, for example, even when the vehicle is running, the actual use upper limit storage capacity capable of charging the battery with the optimum charge amount can be set.

  According to the charge control device of the invention described in claim 3, even if the actual capacity of the battery (actual use upper limit storage capacity−usable lower limit storage capacity) decreases due to deterioration of the battery, the actual use upper limit is set. By updating in the upward direction, the actual capacity of the battery can be kept constant. Further, since the actual capacity of the battery is constant, the user does not feel uncomfortable.

  According to the charge control device of the invention described in claim 4, even if the actual use upper limit storage capacity is set too high due to the update, by updating the actual use upper limit storage capacity in the downward direction, It is possible to prevent deterioration of the capacitor.

  According to the charge control device of the invention described in claim 5, in order to update the actual use upper limit storage capacity from a plurality of candidates for updating the actual use upper limit storage capacity, the optimum actual use upper limit storage capacity is set. Can do.

  According to the charging control device of the sixth aspect of the present invention, since the actual use upper limit storage capacity is updated from a predetermined number of candidates, the optimum actual use upper limit storage capacity can be set.

  According to the charge control device of the invention described in claim 7, it is possible to set the optimum actual use upper limit storage capacity from a plurality of candidates within a predetermined time.

  According to the charge control device of the invention described in claim 8, charging is started at a timing other than the trigger when the usable lower limit storage capacity is reached, and charging is performed in consideration of the remaining amount of the capacitor at the start of charging. Can be done.

  According to the charging control device of the invention described in claim 9, unnecessary charging / discharging of the capacitor is also performed by plug charging that charges the capacitor from an external power supply source, as in the case of charging by a generator in the vehicle. In addition, it is possible to charge the battery while suppressing the deterioration of the capacitor.

  According to the charging control device of the invention described in claim 10, even when the storage battery is deteriorated more than expected due to long-term use, a warning notification can be given to the user of the vehicle, and the replacement of the storage battery is promoted. Etc.

  A charge control device according to an embodiment of the present invention will be described below with reference to the drawings.

  A HEV (Hybrid Electrical Vehicle) includes an electric motor and an internal combustion engine, and travels by the driving force of the electric motor and / or the internal combustion engine according to the traveling state of the vehicle. There are two types of HEVs: a series method and a parallel method. The series-type HEV travels by the driving force of an electric motor using a capacitor as a power source. The internal combustion engine is used only for power generation, and the electric power generated by the driving force of the internal combustion engine is charged in a capacitor or supplied to an electric motor. On the other hand, the parallel HEV travels by the driving force of one or both of the electric motor and the internal combustion engine. A series-parallel HEV that combines both systems is also known.

  Hereinafter, a series system HEV will be described as a representative example, but the present invention can also be applied to other system HEVs.

  FIG. 1 is a block diagram showing the internal configuration of a series-type HEV. In the series-type HEV (hereinafter simply referred to as “vehicle”) shown in FIG. 1, the driving force from the electric motor 105 using the capacitor 101 as a power source is transmitted to the driving wheel 129 via the gear box 115.

  Further, the traveling mode of the vehicle is “EV traveling” or “series traveling”. During EV traveling, the vehicle travels by the driving force of an electric motor (MOT) 105 that is driven by power supply from a battery (BATT) 101. Further, during series travel, the travel is performed by the driving force of the electric motor 105 that is driven by the supply of power from the battery 101 and the supply of electric power generated by the generator (GEN) 109 by driving the internal combustion engine 107.

  The vehicle shown in FIG. 1 includes a battery (BATT) 101, a first inverter (first INV) 103, an electric motor (MOT) 105, a multi-cylinder internal combustion engine (ENG) 107, a generator (GEN) 109, a first 2 inverter (second INV) 111, gear box (hereinafter simply referred to as “gear”) 115, management ECU (MG ECU) 117, motor ECU (MOT ECU) 119, engine ECU (ENG ECU) 121, And a battery ECU (BATT ECU) 123.

  The power storage device 101 has a plurality of power storage cells connected in series and supplies a high voltage of, for example, 100 to 200 V. A storage battery such as a lithium ion battery is mounted on the power storage device 101. Moreover, the full charge capacity of the battery 101 is different even with the same SOC depending on the degree of deterioration due to long-term use or the like.

  The first inverter 103 converts the DC voltage from the battery 101 into an AC voltage and supplies a three-phase current to the electric motor 105. The electric motor 105 generates power (torque) for the vehicle to travel. Torque generated by the electric motor 105 is transmitted to the drive shaft 127 of the drive wheel 129 via the gear 115.

  A multi-cylinder internal combustion engine (hereinafter simply referred to as “internal combustion engine”) 107 generates power (torque), and this power is consumed by the generator 109. The generator 109 is directly connected to the internal combustion engine 107.

  The generator 109 is driven by the internal combustion engine 107 to generate electric power. The electric power generated by the generator 109 is charged in the battery 101 or supplied to the electric motor 105. The second inverter 111 converts the AC voltage generated by the generator 109 into a DC voltage. The electric power converted by the second inverter 111 is charged in the battery 101 or supplied to the electric motor 105 via the first inverter 103.

  The gear 115 is a transmission that converts the driving force from the electric motor 105 into a rotation speed and torque at a desired gear ratio and transmits the converted torque to the drive shaft 127. The gear 115 and the rotor of the electric motor 105 are directly connected.

  The management ECU 117 performs switching between EV travel and series travel, and controls the electric motor 105 and the internal combustion engine 107. The management ECU 117 also includes a requested driving force sensor (not shown) that detects information from a vehicle speed sensor (not shown) that detects the speed of the vehicle and a driving force of the vehicle that is requested by the driver, such as the accelerator opening. ) Is input. In addition, the management ECU 117 performs control related to the calculation of the amount of charge to the capacitor 101 and the amount of discharge from the capacitor 101 (they are collectively referred to as charge / discharge amount) and the state of charge (SOC) of the capacitor 101. Details of these will be described later. The charge / discharge amount is an energy amount.

  The motor ECU 119 controls the electric motor 105 in accordance with an instruction from the management ECU 117. The motor ECU 119 limits the current supplied from the battery 101 to the electric motor 105 when vehicle speed restriction is instructed from the management ECU 117. The engine ECU 121 controls the start and stop of the internal combustion engine 107, throttle valve opening / closing control and fuel injection control in each cylinder, and the number of rotations of the crankshaft of the internal combustion engine 107 in accordance with instructions from the management ECU 117.

  The temperature sensor 131 detects the temperature of the battery 101. Further, the voltage sensor 133 detects the voltage between the terminals of the battery 1. The current sensor 135 detects a charging current to the capacitor 1 and a discharging current from the capacitor 1 (also referred to as a charging / discharging current). These detections can be performed regularly, for example, and the detection timing can be set flexibly.

  The charger 137 receives power supply from an external power supply source 139 outside the vehicle, and converts an AC voltage into a DC voltage.

  The external power supply source 139 is disposed in a charging stand or a home, and supplies power to the charger 137 so as to supply power having an AC voltage to the vehicle.

  Battery ECU 123 estimates the state of charge (SOC) of battery 101 and sends information indicating the state to management ECU 117. At this time, the battery ECU 123 estimates the SOC of the battery 1 by calculating in real time based on the voltage detected by the voltage sensor 133. Hereinafter, the estimated SOC of the battery 101 is also referred to as an estimated SOC. This estimation can be realized because there is a correlation between the SOC and the voltage of the battery 101. FIG. 2 is a diagram illustrating an example of the relationship between voltage and SOC. Further, the SOC may be estimated based on the current detected by the current sensor 135 or the temperature detected by the temperature sensor 131. For example, the SOC may be estimated by correcting the detected voltage with a detected current or a detected temperature.

  Further, the management ECU 117 calculates the amount of charge to the capacitor 101 and the amount of discharge from the capacitor 1 (also referred to as charge / discharge amount) by accumulating the charge / discharge current detected by the current sensor 135 every predetermined period. . This calculation method is called a current integration method. For example, the charge / discharge amount accumulated from the start of charging is calculated.

  Next, the SOC control of the battery 101 executed by the management ECU 117 will be described.

  In the present embodiment, the limit upper limit SOC and the usable lower limit SOC are set in advance, and the management ECU 117 sets the actual use upper limit SOC in the meantime, and charges the battery 101 based on the estimated SOC and the charge / discharge amount. Is performed between the usable lower limit SOC and the actual usable upper limit SOC. The actual use upper limit SOC is a variable value, and the limit upper limit SOC and the usable lower limit SOC are fixed values.

  First, the management ECU 117 sets the SOC charged with a predetermined capacity from the usable lower limit SOC as the first actual use upper limit SOC (initial setting of the actual use upper limit SOC). Then, even if the capacity at the actual use upper limit SOC decreases due to the deterioration of the battery 101, the actual use upper limit SOC is updated in the upward direction by the predetermined capacity from the usable lower limit SOC so that the predetermined capacity can always be secured. To do. Hereinafter, the predetermined capacity to be kept constant is also referred to as a target capacity.

  FIG. 3 is a diagram showing an example of the relationship between the capacitor usage period and the voltage at each SOC of the capacitor 101. FIG. 4 is a diagram showing an example of the relationship between the storage device usage period and the capacity of the storage device 101 at the actual use upper limit SOC. When the battery 101 is used by repeatedly charging with the actual use upper limit SOC set for the first time, as shown in FIG. 4, a capacity equal to or higher than a predetermined switching threshold can be secured at time t1 as the capacity of the actual use upper limit SOC. Disappear. This switching threshold is, for example, the same value as the minimum necessary capacity required for traveling. At this time (time t1), the management ECU 117 updates the actual use upper limit SOC in the upward direction as shown in FIG. Then, when charging is repeated several times with the updated actual use upper limit SOC and the charger 101 is used, as shown in FIG. 4, the capacity of the updated actual use upper limit SOC is equal to or greater than a predetermined switching threshold. It cannot be secured again at t2. At this time (time t2), the management ECU 117 again updates the actual use upper limit SOC in the increasing direction, as shown in FIG. Thus, the management ECU 117 repeats updating the actual use upper limit SOC when the capacity at the actual use upper limit SOC cannot secure the switching threshold value. If this update is performed in a short cycle, the change in the SOC capacity is reduced, and it is possible to prevent the vehicle behavior, for example, the travel distance for EV travel from changing rapidly without driving the ENG.

  By performing such SOC control, when the battery 101 is deteriorated as expected, as shown in FIG. 5, when the battery 101 reaches the guaranteed lifetime, the capacity to be used is secured (that is, the target capacity is secured). ) Is possible, but soon the target capacity cannot be secured. That is, when the life guarantee years have passed, the usable capacity = the target capacity. FIG. 5 is a diagram illustrating an example of the relationship between the years of use and the usable capacity when the battery 101 is deteriorated as expected.

  Further, in the case where the storage battery 101 has deteriorated below the expected level, as shown in FIG. 6, when the storage battery 101 reaches the guaranteed lifetime, the target capacity can still be secured, and after that, the target capacity can be secured for a while. Is possible. That is, when the guaranteed lifetime has elapsed, the usable capacity> the target capacity. FIG. 6 is a diagram illustrating an example of the relationship between the number of years of use and the usable capacity when the battery 101 is deteriorated below the expected level.

  Further, when the battery 101 is deteriorated more than expected, as shown in FIG. 7, when the battery 101 reaches the guaranteed lifetime, it is already impossible to secure the target capacity. That is, the usable capacity <the target capacity when the lifetime guarantee years have elapsed. FIG. 7 is a diagram illustrating an example of the relationship between the years of use and the usable capacity when the battery 101 is deteriorated more than expected. In addition, when deterioration more than assumption has generate | occur | produced like FIG. 7, you may estimate that the malfunction has generate | occur | produced in the electrical storage device 101, and you may make it notify. Such a failure estimation is executed by the management ECU 117, and a notification unit (not shown) notifies the fact.

  Regarding the storage battery 101 that deteriorates as shown in FIGS. 5 to 7, the relationship between the number of years of use and the actual use upper limit SOC is as shown in FIG. That is, for example, when the actual use upper limit SOC is set to 50 (%) and the use is assumed to be L1, if the deterioration is as expected, the increase in the actual use upper limit SOC is increased as shown in L2 in the case of deterioration below the assumption. The degree is relatively small. On the other hand, in the case of deterioration more than expected, as shown in L3, the increase degree of the actual use upper limit SOC becomes relatively large. FIG. 8 is a diagram illustrating an example of the relationship between the years of use of the battery 101 and the actual use upper limit SOC for each deterioration state.

  In this way, the management ECU 117 controls the actual use upper limit SOC, and charging the battery 101 between the usable lower limit SOC and the actual use upper limit SOC as described above, regardless of the years of use of the battery 101. Since the same capacity is used, even if the usable capacity of the battery decreases from the start of the use of the battery 101, the ratio of the electric running does not change from when it is new, and the user does not feel uncomfortable. In addition, since the SOC usage range of the battery is limited to the actual use upper limit SOC charged only by the target capacity (≦ usable capacity) from the usable lower limit SOC, the battery 101 of the battery 101 is maintained by maintaining a high SOC state. It is possible to suppress deterioration.

  Next, the operation when charging the battery 101 of the vehicle shown in FIG. 1 will be described.

  FIG. 9 is a flowchart illustrating an example of an operation when updating the actual use upper limit SOC. In FIG. 9, for example, it is assumed that charging of the battery 101 is started when the estimated SOC falls below the usable lower limit SOC due to capacity consumption during traveling of the vehicle.

  When the vehicle travels and consumes power, the capacity of the battery 101 is consumed (step S101). The management ECU 117 determines whether or not the estimated SOC has reached the usable lower limit SOC of the battery 101 due to capacity consumption (step S102). If it is determined that the usable lower limit SOC has been reached, the management ECU 117 resets the charge / discharge amount E so that E = 0 (step S103). After the charge / discharge amount E is reset, calculation of the charge / discharge amount is started.

  After the charge / discharge amount is reset, power generation by the internal combustion engine 107 and the generator 109 is started based on a command from the management ECU 117, and charging of the battery 101 is started (step S104). After the start of charging, the management ECU 117 determines whether or not the estimated SOC has reached the actual use upper limit SOC of the battery 101 (step S105).

  When determining that the actual use upper limit SOC has been reached, the management ECU 117 determines whether or not the calculated charge / discharge amount is equal to or less than a specified value (step S106). When it is determined that the charge / discharge amount is larger than the specified value, the management ECU 117 controls to stop the charging of the battery 101 (step S111). When stopping charging, based on a command from the management ECU 117, power generation by the internal combustion engine 107 and the generator 109 is stopped, and charging of the battery 101 is stopped. The specified value to be compared with the charge / discharge amount is set in advance.

  If the charge / discharge amount is equal to or less than the specified value, the management ECU 117 controls to continue charging the battery 101 (step S107), and determines whether or not the calculated charge / discharge amount has reached the specified value ( Step S108). If it is determined that the specified value has not been reached, the management ECU 117 controls to continue charging the battery 101.

  When it is determined that the charge / discharge amount has reached the specified value, the management ECU 117 controls to stop the charging of the battery 101 (step S109). Then, the management ECU 117 updates the actual use upper limit SOC of the battery 101 to the estimated SOC of the battery 101 when the charging is stopped (step S110). Here, the actual use upper limit SOC is updated in the upward direction.

  On the other hand, when it is determined in step S105 that the estimated SOC has not reached the actual use upper limit SOC, the management ECU 117 determines whether or not the calculated charge / discharge amount has reached a specified value (step S112). When it is determined that the charge / discharge amount has not reached the specified value, the process returns to step S104, and the management ECU 117 controls to continue charging the battery 101.

  When it is determined that the charge / discharge amount has reached the specified value, the management ECU 117 controls to stop the charging of the battery 101 (step S113). Then, the management ECU 117 updates the actual use upper limit SOC of the battery 101 to the estimated SOC of the battery 101 when the charging is stopped (step S114). Here, the actual use upper limit SOC is updated in the downward direction.

  By performing the process of FIG. 9, the battery can be charged while preventing the user from feeling uncomfortable while driving, and without charging / discharging of the unnecessary battery, while suppressing the progress of deterioration of the battery, Life can be extended. For example, when the battery deteriorates, it is conceivable that the charge / discharge amount does not reach the specified value even when the estimated SOC reaches the actual use upper limit SOC. In this case, it is possible to perform control to increase the actual use upper limit SOC and minimize deterioration of the capacitor without causing the user to feel uncomfortable.

  Further, since the charge / discharge amount calculated by the management ECU 117 is calculated by integration every predetermined period, an integration error tends to increase. Is also included in the charge / discharge amount, there is a possibility that the error is further increased. For example, if the actual use upper limit SOC is set too high due to an error, it is conceivable that the charge / discharge amount reaches the specified value even if the estimated SOC does not reach the actual use upper limit SOC. Even in such a case, since there is no problem even if the actual use upper limit SOC is lowered, it is possible to further prevent deterioration of the battery 101 by performing control to lower the actual use upper limit SOC.

  Next, FIG. 10 is a flowchart showing another example of the operation when the actual use upper limit SOC is updated. In FIG. 10, for example, it is assumed that charging of the battery 101 is started when a connection portion extending from the charger 137 is connected to the external power supply source 139 while the vehicle is stopped.

として残存電量を算出する。また、直近に推定ＳＯＣが使用可能下限ＳＯＣとなったときからの充放電量を図示しない記憶部に記憶しておき、プラグ接続時における記憶部に記憶された充放電量を蓄電器１０１の残存電量としてもよい。 When the management ECU 117 determines that a plug as a connecting portion extending from the battery 137 is inserted and connected to the external power supply source 139 (step S201), the remaining power of the battery 101 at the time of connection is calculated (step S202). . In this case, for example, the actual usable SOC set at the time of plug connection is B (%), the lower limit of usable SOC is C (%), the target value of charge / discharge amount is A (Wh), and estimated at the time of plug connection When the estimated SOC is X (%), the remaining electric energy E0 at the time of plug connection is

The remaining electric energy is calculated as follows. In addition, the charge / discharge amount from when the estimated SOC has recently reached the usable lower limit SOC is stored in a storage unit (not shown), and the charge / discharge amount stored in the storage unit at the time of plug connection is stored in the remaining charge of the battery 101. It is good.

  After calculating the remaining electric energy of the battery 101, the management ECU 117 calculates the charge / discharge amount using E0 as an initial value (step S203), and starts plug charging for receiving the power supply from the external power supply source 139 and charging the battery 101. Control is performed (step S204). Since the charge / discharge amount has E0 as an initial value, the charge / discharge amount calculated after the start of charging includes the charge / discharge amount due to plug charging as well as the remaining amount of electricity of the battery 101 at the time of plug connection.

  After the start of charging, the same processing as in steps S105 to S114 in FIG. 9 is performed. However, when comparing the charge / discharge amount with the specified value (corresponding to the target value A of the charge / discharge amount) in steps S106, S108, and S112, as described above, as the charge / discharge amount, A comparison is made including the remaining electricity of the battery 101. If it is determined in step S112 that the charge / discharge amount has not reached the specified value, the process returns to step S204, and the management ECU 117 controls to continue charging the battery 101.

  By performing the process of FIG. 10, the battery can be charged while preventing the user from feeling uncomfortable while driving, and without charging / discharging of the unnecessary battery, while suppressing the progress of deterioration of the battery, Life can be extended. Further, since the charge / discharge amount calculated by the management ECU 117 is calculated by integration every predetermined period, an integration error tends to increase. Is also included in the charge / discharge amount, there is a possibility that the error is further increased. On the other hand, since plug charging is performed in FIG. 10, there is no error due to discharging, so the actual use upper limit SOC can be updated more accurately, and deterioration of the battery 101 can be prevented.

  In the present embodiment, it is assumed that charging of the battery 101 is started when the connecting portion extending from the charger 137 is connected to the external power supply source 139 while the vehicle is stopped. For example, when the internal combustion engine 107 is operated when heating is performed in cold weather, or when the generator 109 is operated at the time of a high output request in which the electric power of the battery 101 is insufficient while the vehicle is running, etc. The remaining electric energy can be obtained.

  FIG. 11 is a flowchart showing an example of further operation when the actual use upper limit SOC is updated. In FIG. 11, it is assumed that the actual use upper limit SOC is updated with an SOC selected from a plurality of SOC candidates.

  First, the same processing as in FIG. 9 is performed. However, the actual use upper limit SOC is not updated in steps S110 and S114 after the charging is stopped in steps S109 and S113. Instead of performing this update, the management ECU 117 stores the estimated SOC at the time of charging stop as a candidate n of the actual use upper limit SOC in a storage unit (not shown) after the charging is stopped in steps S109, S111, and S113 (step S301). . That is, when the charge / discharge amount calculated by the management ECU 117 after the start of charging reaches a specified value, the actual use upper limit SOC is not updated immediately, but the estimated SOC at the time of charge stop is once updated. As a candidate for storage in a storage unit (not shown).

  And management ECU117 judges whether the number of candidates memorize | stored in the memory | storage part reached the regulation number (step S302). If the specified number has not been reached, the process returns to step S101 to search for the next candidate.

  When the number of candidates reaches the specified number, the management ECU 117 selects an optimum SOC from a plurality of candidates stored in the storage unit, and updates the actual use upper limit SOC to the selected SOC (step S303). As a selection method of the SOC, for example, the median value of a plurality of candidates is selected, the average value of the plurality of candidates is selected, the average value of the maximum value and the minimum value among the plurality of candidates is selected, and the most frequent value of the plurality of candidates Can be considered.

  By performing the processing of FIG. 11, each time the calculated charge / discharge amount reaches a specified value, the estimated SOC is stored in a storage unit (not shown), and an optimum SOC is selected from a plurality of SOC candidates. Even if there are some errors in the SOC candidate values, the actual use upper limit SOC can be updated more accurately.

  Note that although it has been described in step S302 whether or not the number of candidates has reached the specified number, for example, it may be determined whether or not a predetermined time has elapsed since the start of charging. That is, the estimated SOC is stored in the storage unit every time the charge / discharge amount reaches the specified value for a predetermined time.

  Further, in FIG. 11, it is assumed that charging is performed by the same processing as in FIG. 9, that is, power generation by the internal combustion engine 107 and the generator 109. However, the same processing as in FIG. The optimum SOC candidate may be selected from the above, and the actual use upper limit SOC may be updated.

  Although the present embodiment has been described using HEV, other electric vehicles such as EV (Electric Vehicle: electric vehicle), PHEV (Plugin Hybrid Electric Vehicle: plug-in hybrid electric vehicle), FCV (Fuel Cell Vehicle: fuel cell). The present invention is also applicable to electric vehicles such as automobiles) and PFCVs (Plugin Fuel Cell Vehicles).

  INDUSTRIAL APPLICABILITY The present invention is useful for a charge control device and the like that can be charged while suppressing the progress of deterioration of the capacitor without performing unnecessary charging and discharging of the capacitor.

The block diagram which shows an example of the internal structure of the vehicle in embodiment of this invention The figure which shows an example of the relationship between a voltage and SOC The figure which shows an example of the relationship between the usage period of a capacitor | condenser and SOC in embodiment of this invention The figure which shows an example of the relationship between the use period of the electrical storage device in the embodiment of this invention, and the capacity | capacitance in actual use upper limit SOC. The figure which shows an example of the relationship between the years of use when the electrical storage device in embodiment of this invention deteriorates as expected, and a usable capacity | capacitance. The figure which shows an example of the relationship between the years of use when the electrical storage device in embodiment of this invention deteriorates below assumption, and usable capacity. The figure which shows an example of the relationship between the years of use and usable capacity | capacitance when the electrical storage device in embodiment of this invention deteriorates more than assumption. The figure which shows an example of the relationship between the years of use of the electrical storage device for every deterioration condition and actual use upper limit SOC in embodiment of this invention The flowchart which shows an example of the operation | movement at the time of updating real use upper limit SOC in embodiment of this invention. The flowchart which shows an example of another operation | movement at the time of updating real use upper limit SOC in embodiment of this invention. The flowchart which shows an example of another operation | movement at the time of updating real use upper limit SOC in embodiment of this invention. It is a figure which shows an example of the relationship between the durable days of a capacitor | condenser, and a capacity | capacitance fall rate. It is a figure which shows an example of the relationship between the years of use of the conventional storage battery, and usable capacity.

Explanation of symbols

101 Battery (BATT)
103 1st inverter (1st INV)
105 Electric motor (MOT)
107 Internal combustion engine (ENG)
109 Generator (GEN)
111 Second inverter (second INV)
115 Gear 117 Management ECU (MG ECU)
119 Motor ECU (MOT ECU)
121 Engine ECU (ENG ECU)
123 Battery ECU (BATT ECU)
127 Drive shaft 129 Drive wheel 131 Temperature sensor 133 Voltage sensor 135 Current sensor 137 Charger 139 External power supply source

Claims (10)

A charge control device for a rechargeable battery,
A voltage detector for detecting the voltage of the capacitor;
A current detector for detecting a charge / discharge current of the battery;
Based on the voltage detected by the voltage detection unit, a storage capacity estimation unit that estimates the storage capacity of the battery,
A charge / discharge amount calculation unit that calculates a charge / discharge amount from the start of charging of the battery by integrating the charge / discharge current detected by the current detection unit;
Based on the storage capacity of the storage battery estimated by the storage capacity estimation unit and the charge / discharge amount of the storage battery calculated by the charge / discharge amount calculation unit, the storage capacity of the storage battery is less than or equal to the actual use upper limit storage capacity. And a charging control unit for controlling charging of the battery,
The charge controller is
When updating sets the actual use upper limit charge capacity, when the charge and discharge amount calculated by the charge and discharge amount calculating unit when performing charging of the capacitor has reached a predetermined value, estimated by the battery capacity estimation unit A charge control device that updates and sets the stored storage capacity to the actual use upper limit storage capacity. The charge control device according to claim 1,
The charge controller is
When updating sets the actual use upper limit charge capacity, calculated by the charge and discharge amount calculating unit from the time the power storage capacity estimated by the battery capacity estimation unit when performing charging of the capacitor can be lower storage capacity used A charge control device that executes a first charge mode that sets the storage capacity estimated by the storage capacity estimation unit to the actual use upper limit storage capacity when the charged / discharged amount reaches the predetermined value. The charge control device according to claim 2,
The charge controller is
When the actual use upper limit storage capacity is updated and set, even if the storage capacity estimated by the storage capacity estimation unit reaches the actual use upper limit storage capacity, the charge / discharge amount calculated by the charge / discharge amount calculation unit is A charge control device that controls to charge the capacitor until a predetermined value is reached. The charge control device according to claim 2,
The charge controller is
When the storage capacity estimated by the storage capacity estimation unit has not reached the actual use upper limit storage capacity, but the charge / discharge amount calculated by the charge / discharge amount calculation unit has reached a predetermined value, the battery is charged. Charge control device for controlling to stop. The charge control device according to any one of claims 2 to 4,
A storage unit that stores the storage capacity estimated by the storage capacity estimation unit each time the charge / discharge amount reaches a predetermined value;
The charge control unit is a charge control device that sets the actual use upper limit storage capacity based on the storage capacity stored in the storage unit when the actual use upper limit storage capacity is updated and set . The charge control device according to claim 5,
The storage unit stores a predetermined number of storage capacities estimated each time the charge / discharge amount reaches the predetermined value. The charge control device according to claim 5,
The storage unit stores a predetermined number of storage capacities estimated every time the charge / discharge amount reaches the predetermined value for a predetermined time. The charge control device according to any one of claims 1 and 3 to 7,
The charge controller is
Storage capacity estimated by the battery capacity estimation unit executes the second charge mode when the charging of the capacitor is initiated at a greater state than can limit charge capacity use,
In the second charging mode, based on the actual use upper limit storage capacity, the usable lower limit storage capacity, the storage capacity estimated by the storage capacity estimation unit, and the predetermined value at the start of charging. Estimate the remaining amount of the battery at the start of charging,
The charge control device
A charge control device including the remaining amount as the charge / discharge amount when charging the battery. The charge control device according to claim 8,
The second charging mode is executed when the battery is connected to an external power supply outside the vehicle on which the battery is mounted,
The remaining amount is B when the connection between the capacitor and the external power source is B, C is the lower limit storage capacity that can be used, X is the storage capacity estimated by the storage capacity estimation unit, and When the predetermined value is A, the charge control device is estimated by (X−C) / (B−C) × A. The charge control device according to any one of claims 1 to 9,
The limit upper storage capacity is initially set,
The charge controller is
When said practically Kiri蓄 capacity exceeds the limit the upper limit battery capacity, it estimated that a failure in the capacitor occurs, the charge control device for notifying the notification unit.

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