JP2008263679A - Lead battery charging controller and lead battery charging control method employing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lead battery charging controller for enhancing the charging efficiency by eliminating charging polarization during regenerative charging of a vehicle mounting a lead battery, thereby enhancing acceptance of regeneration. <P>SOLUTION: The lead battery charging controller 100 for controlling regenerative charging of a lead battery 40 mounted on a vehicle comprises a means 10 for detecting the charging state of the lead battery, and a means 30 for controlling charging of the lead battery based on the charged state detected by the charging state detecting means. When the charging state detecting means detects the fact that the lead battery is being charged before the vehicle begins deceleration, the charging control means performs regenerative charging control for starting regenerative charging after discharging the lead battery for a short time. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a lead battery charge control device and a lead battery charge method using the same, and more particularly, to a lead battery charge control device and a lead battery charge control method for controlling regenerative charge for collecting regenerative power during vehicle deceleration.

Conventionally, a battery charge control device for a hybrid vehicle, comprising charge / discharge prediction means for predicting a future charge / discharge state of the battery and target value change means for changing a target charge value of the battery based on a charge / discharge prediction result. If the battery is expected to be charged in the future, the target charge amount is changed to a low value so as to decrease the charge amount in advance so that the charge amount can be increased at that time. There is known a technique that makes it possible to widen the width (for example, see Patent Document 1).
JP 2001-268719 A

  However, in the configuration described in Patent Document 1 described above, since the charge target amount is changed based on the prediction of the charge / discharge state, the prediction and the actual charge / discharge state are not necessarily consistent with each other. It does not necessarily lead to an improvement in charge / discharge efficiency.

  Further, since the contents described in Patent Document 1 are intended for HV batteries for hybrid vehicles, HV batteries using nickel metal hydride and the like are assumed, and improvement in charge efficiency reduction due to charge polarization peculiar to lead batteries, etc. Is not considered at all.

  Therefore, an object of the present invention is to provide a lead battery charge control device that eliminates charge polarization and improves regenerative acceptability during regenerative charging of a vehicle on which a lead battery is mounted, thereby increasing charging efficiency.

In order to achieve the above object, a lead battery charge control device according to a first invention is a lead battery charge control device that controls regenerative charge of a lead battery mounted on a vehicle,
Charge state detection means for detecting a charge state of the lead battery;
Charge control means for performing charge control of the lead battery based on the charge state detected by the charge state detection means;
The charging control means starts the regenerative charging after discharging the lead battery for a short time when the charge state detecting means detects that the lead battery is being charged at the start of deceleration of the vehicle. Regenerative charge control is performed.

  As a result, when there is a charge history in the lead battery during regenerative charge, the charge polarization can be eliminated by short-time discharge, and the rechargeability can be started after improving the acceptability of the lead battery. Charging efficiency can be increased. Moreover, since the regenerative charge efficiency at the time of a fail cut can be improved, a fuel consumption can be improved.

2nd invention is the lead battery charge control apparatus which concerns on 1st invention,
The charge state detection means detects the charge state based on the SOC of the lead battery,
The charge control means performs the regenerative charge control when the SOC is equal to or greater than a predetermined target SOC value. Thereby, this regenerative charge control can be executed only when there is a margin in the state of charge of the lead battery, and the charging efficiency of regenerative charge can be reliably increased.

3rd invention is the lead battery charge control apparatus which concerns on 1st or 2nd invention,
A vehicle speed sensor,
The charge control means starts the regenerative charge of the lead battery without discharging for a short time when the vehicle speed detected by the vehicle speed sensor is less than a predetermined value. As a result, when the vehicle speed is not sufficiently high, the generated regenerative power itself is small, so if it is discharged for a short time, the regenerative power cannot be recovered sufficiently. Efficiency can be improved and appropriate control can be performed according to the situation.

4th invention is the lead battery charge control apparatus which concerns on 3rd invention,
An acceleration sensor;
The vehicle further comprises: a vehicle speed detected by the vehicle speed sensor; and a sudden braking detection means for detecting sudden braking of the vehicle based on the acceleration detected by the acceleration sensor.
The charging control means starts the regenerative charging of the lead battery without discharging for a short time when the sudden braking detecting means determines that the vehicle is suddenly braking. . Thus, when the regenerative charging time during sudden braking is short, regenerative charging can be started without discharging for a short time, charging efficiency can be increased, and control according to the situation can be performed.

A fifth invention is the lead battery charge control device according to any one of the first to fourth inventions,
When the charge state detection means detects that the lead battery is being discharged at the start of deceleration of the vehicle,
The charge control means starts the regenerative charge of the lead battery without performing the short-time discharge. Thereby, since there is no possibility of charge polarization and the acceptability is high while the lead battery is being discharged, high charging efficiency can be obtained by starting regenerative charging as it is.

A lead battery charge control method according to a sixth aspect of the present invention is a lead battery charge control method for controlling regenerative charge of a lead battery mounted on a vehicle,
When the vehicle is decelerated, the charge state of the lead battery is detected,
According to the detected state of charge, when the lead battery is being charged, the regenerative charge is started after the lead battery is discharged for a short time.

  Thereby, the charge polarization by the charge log | history of a lead battery can be eliminated, the acceptability of the lead battery at the time of regenerative charge can be improved, and the charge efficiency of regenerative charge can be improved. Moreover, since the regenerative charge efficiency at the time of a fail cut can be improved, a fuel consumption can be improved.

  According to the present invention, charging efficiency in regenerative charging of a lead battery can be increased.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a functional block diagram of a lead battery charge control device 100 according to an embodiment to which the present invention is applied. In FIG. 1, the lead battery charge control device 100 according to the present embodiment includes a charge state detection 10 and a charge control means 30. And the lead battery charge control apparatus 100 which concerns on a present Example may be provided with the speed sensor 21, the acceleration sensor 22, and the sudden braking determination means 20 as needed. Note that the lead battery charge control device 100 according to the present embodiment functions as an in-vehicle device mounted on a vehicle (not shown).

  Moreover, the lead battery 40, the alternator 50, the electric load 60, etc. may be further provided as other components related to the lead battery charge control device 100 according to the present embodiment.

  The charge state detection means 10 is a means for detecting and monitoring the charge state of the lead battery 40. The charging state of the battery 40 includes, for example, a current sensor 11 that detects charging / discharging current of the lead battery 40, a voltage sensor 12 that detects battery voltage, and a temperature sensor 13 that detects battery temperature. May be detected.

  The charge state detection means 10 may calculate and store the current integrated value of the charge / discharge current of the lead battery 40 detected by the current sensor 11. By calculating the integrated value of the input / output current (charging / discharging current) of the lead battery 40, the charge balance state of the lead battery 40 can be grasped, and the charge state can be calculated based on this.

  For example, the state of charge detection unit 10 may calculate the state of charge by SOC (State of Charge). By expressing the state of charge using SOC, the ratio of the current remaining capacity to the initial charge amount or the maximum charge amount of the lead battery 40 can be expressed as a percentage, and the charge state of the lead battery 40 can be easily managed. become.

  The charging state detection means 10 may detect the output voltage and temperature of the lead battery 40 by the voltage sensor 12 and the temperature sensor 13 in addition to the current sensor 11, and may manage the lead battery 40 using these as well. The voltage sensor 11 monitors whether or not the lead battery 40 is outputting the required voltage. The temperature sensor 13 monitors the output of the lead battery 40 because the output of the lead battery 40 decreases as the battery temperature increases. The charge state detection means 10 may comprehensively monitor the state of the lead battery 40 from these various detection means.

  The charging control unit 30 is a control unit that controls charging of the lead battery 40 based on the charging state of the lead battery 40 detected by the charging state detection unit 10. The charging control unit 30 may perform charging control by controlling the power generation voltage of the alternator 50 based on the integrated current value detected by the charging state detection unit 10 and the SOC.

  The charging control means 30 according to the present embodiment also performs regenerative charging control when the vehicle is decelerated by a brake and generating regenerative electric power, in addition to normal charging control of the lead battery 40 during traveling of the vehicle. Although details of the control contents will be described later, the charging control means 30 performs various controls for maximizing the charging efficiency of regenerative charging.

  The charge control means 30 may be configured as an ECU (Electronic Control Unit) in order to perform various control calculations necessary for charge control. The charging control means 30 may be operated by a program, like a computing means such as a computer, or may be constituted by a certain electric circuit.

  In FIG. 1, the charging control unit 30 is integrally configured to include the charging state detection unit 10 and the sudden braking determination unit 20, but may be configured separately from these. As long as the charge control means 30 is provided with the control calculation function which performs charge control, the aspect of the realization means will not ask | require.

  The vehicle speed sensor 21 is a detection means for detecting the speed of the vehicle, and for example, a wheel speed sensor provided on a wheel may be applied. The vehicle speed detected by the vehicle speed sensor 21 may be sent to the charging control means 30 and / or the sudden braking determination means 20. The detected vehicle speed is determined by the charging control means 30 whether or not it is above a certain threshold, and may be used to determine whether or not to execute the regenerative charging control according to the present embodiment. In 20, it may be used to determine whether or not the vehicle is suddenly braking.

  Further, the vehicle speed sensor 21 may detect deceleration of the vehicle when performing regenerative charging. The deceleration of the vehicle during regenerative charging may be detected by various means such as a moving position of a brake pedal or the like, but may be detected by a vehicle speed sensor 21.

  The acceleration sensor 22 is a detecting means for detecting the acceleration of the vehicle. In the lead battery charge control device 100 according to the present embodiment, the acceleration sensor 22 is used particularly for detecting the acceleration in the front-rear direction. The acceleration detected by the acceleration sensor 22 is sent to the sudden braking determination means 20 together with the vehicle speed detected by the vehicle speed sensor 21, and is used to determine whether or not the vehicle is suddenly braking.

  The acceleration sensor 22 may be used for vehicle deceleration. When the vehicle decelerates, the acceleration sensor 22 indicates negative acceleration at that time, and this may be detected to recognize the deceleration of the vehicle.

  The sudden braking determination means 20 is a determination calculation means for determining whether or not the vehicle is suddenly braking based on the vehicle speed detected by the vehicle speed sensor 21 and the longitudinal acceleration of the vehicle detected by the acceleration sensor 22. It is. For example, if the vehicle speed decreases and the acceleration increases greatly negatively, it can be determined that sudden braking is applied and sudden braking with a large deceleration is occurring.

  The sudden braking determination means 20 can determine whether or not sudden braking is being performed based on, for example, only the speed of the vehicle speed sensor 21, but it is determined together with the acceleration detected by the acceleration sensor 22. By performing the above, it is possible to make a more accurate determination of sudden braking. If necessary, it may be configured to detect the movement position of the brake pedal, etc., and determine based on these.

  The lead battery 40 is a power supply source for supplying power to the vehicle, and is configured as a chargeable / dischargeable lead storage battery. The lead battery 40 has good acceptability at the initial stage of charging, but as charging progresses, there is a problem that the charge acceptability of the negative electrode decreases due to so-called charge polarization in which lead sulfate crystals generated at the negative electrode accumulate. Such lead sulfate crystals have low activity and cannot be reduced to lead as an active material by simple charging. Therefore, if charging is continued as it is, there is a problem that charging efficiency is lowered. Although details will be described later, in the lead battery charge control device 100 according to the present embodiment, this problem is solved by short-time discharge.

  The alternator 50 is a power generation means that is driven by an engine (not shown), converts rotational force into electric energy to generate electric power, supplies the electric load 60, and charges the lead battery 40. In the lead battery charging control apparatus 100 according to the present embodiment, the alternator 50 also generates so-called regenerative power that is generated when the vehicle is decelerated.

  The regulator 51 is a generated voltage control means for controlling the generated voltage of the alternator 50. The alternator 50 generates electric power of the voltage set by the regulator 51.

  The regulator 51 may be instructed by the charge control means 30 to generate a power generation voltage, and may be controlled to determine a set power generation voltage. Further, the set voltage of the regulator 51 may be variably controlled by the charge control means 30. Thereby, for example, when it is desired to promote charging from the alternator 50 to the lead battery 40, the power generation amount is controlled such that the power generation voltage is set high, and when the charge amount is decreased, the power generation voltage is set low. It becomes possible.

  Thus, the alternator 50 may be configured as a voltage variable alternator using the regulator 51.

  Various modes may be applied to the regulator 51. For example, the regulator 51 may be configured as an IC (Integrated Circuit) regulator so that the generated voltage can be variably set.

  The electric load 60 refers to various electrical components mounted on the vehicle. For example, a blower motor, a wiper, or the like may be used, or an electric fan or a mirror heater may be used. The electric load 60 is electrically connected to both the lead battery 40 and the alternator 50, and is supplied with electric power from both or one side and is driven. Although details will be described later, in the lead battery charge control device 100 according to the present embodiment, a short-time discharge is performed in order to eliminate the charge polarization of the lead battery 40 described above. This is done by supplying power from the lead battery 40 to the required electrical load 60. Therefore, for example, a cooling fan or the like that cools the cooling water is also used for discharging the lead battery 40.

  Next, the content of the regenerative charge control performed by the lead battery charge control device 100 according to the present embodiment will be described with reference to FIG.

  FIG. 2 is a diagram illustrating an example of the relationship between the passage of time, the vehicle speed, and the SOC. In FIG. 2, the horizontal axis indicates time t (s), and the vertical axis indicates the vehicle speed V (km / h) and the SOC (%) of the lead battery 40.

  In FIG. 2, the lower graph shows the relationship between vehicle speed and time, the upper graph shows the relationship between time and SOC, and the upper and lower graphs show the correlation on the same time axis. In the SOC graph, since the SOC control range of the lead battery 40 is determined in advance, the state of charge of the lead battery 40 is controlled so that the SOC falls within this range. The SOC control range varies depending on the type and type of the lead battery 40, but may be set to a value of approximately 80% or more, for example, Qr = 90% or Qr = 95%. If the charge amount of the lead battery 40 is lower than a certain amount, the charge capacity or power supply ability is remarkably lowered and the life of the lead battery 40 itself is shortened. There is a lower limit for a certain amount of charge (amount of electricity stored). And the control which is not less than the lower limit is made | formed by the charge control means 30 of the lead battery charge control apparatus 100 which concerns on a present Example. Various representation methods may be used for the index indicating the charge amount. In this example, SOC (State of Charge) is used, and the charge amount is expressed as a percentage with respect to the maximum charge amount as 100%. .

  In FIG. 2, when the vehicle starts running after the vehicle has started idling slightly, the vehicle speed V gradually increases, and the vehicle speed V increases until t = t1, reaching V = V1. At this time, since the lead battery 40 is in a state of supplying electric power to the electric load of the vehicle, the lead battery 40 continues to discharge and the SOC continues to decrease. That is, the SOC is initially Q1, and thereafter continues to decrease.

  When t = t1, the vehicle reaches a stable traveling speed, and then maintains a constant vehicle speed until t = t3. At this time, the SOC continues to decrease due to discharge, but when the SOC reaches Q2, the charge approaches the lower limit of the SOC control range, and charging starts at t = t2. Such state monitoring of the SOC is performed by the charging state detection unit 10, and charging control based on the charging state detected by the charging state detection unit 10 may be executed by the charging control unit 30.

  The vehicle travels at a constant speed from t = t1 to t = t3, then accelerates further, and the vehicle speed V increases again from t = t3, and the vehicle speed increases until t = t4. At this time, the lead battery 40 continues to be charged. Further, the vehicle speed V is a speed exceeding the vehicle speed threshold value Vth. The vehicle speed threshold value Vth is a threshold value for determining whether or not to apply regenerative charge control that has undergone short-time discharge according to the present embodiment, and may be set to a low vehicle speed of about 20 km / h, for example. Although details will be described later, when the vehicle speed is less than a certain value, regenerative charging may not be possible if the battery is discharged for a short time, and is set to prevent such a situation.

  The vehicle reaches a stable speed at t = t4 and travels at a constant speed from t = t4 to t = t5. At this time, the lead battery 40 continues to be charged.

  It is assumed that the vehicle starts decelerating when t = t5 is reached. At this time, in general, the lead battery 40 is controlled to perform regenerative charging for recovery of regenerative power. In the lead battery charging control device 100 according to the present embodiment, t = t5 to t = t6. First, the battery is discharged for a short time, and then charging is started at t = t6 and charged until t = t8. This is because the lead battery 40 continued to be charged between t = t2 and t = t5, and the lead battery 40 was in a charged state even when the vehicle started decelerating. This is because polarization may occur and the acceptability of the lead battery 40 may be reduced. In order to eliminate this charge polarization, the lead battery charge control device 100 according to the present embodiment first discharges for a short time from t = t5 to t = t6 to first eliminate the charge polarization, and accept the lead battery 40. After improving the performance, regenerative charging is started at t = t6. Regenerative charging is performed until t = t8, and the regenerative charging efficiency in the regenerative region from t = t5 to t = t7 is increased.

  In FIG. 2, the regenerative region t = t5 to t7 is expressed short and the time ratio between discharge and charge is expressed small. For example, when the discharge time (t = t5 to t6) is about 3 to 5 seconds, If the region (t = t5 to t7) is about 30 to 40 seconds, a sufficient regenerative charging time can be secured, and if charging acceptability is improved by short-time discharge before the start of regenerative charging, the charging efficiency is remarkably increased. I can keep it. In general, since the vehicle is decelerated, the engine speed decreases, and a fail cut occurs when the engine speed falls below a certain level, the regenerative power generated in the area where the fail cut occurs is completely generated by the fuel. Will not be affected. Therefore, by efficiently performing regenerative charging, it is possible to reduce power generation during fuel supply and contribute to improving fuel efficiency. In addition, discharging is performed by operating the electric load 60. At that time, it is preferable to operate the electric load that needs to be operated during the traveling. Thereby, discharge power can be used effectively. For example, an electric fan for cooling water may be operated. Note that after regenerative charging, the vehicle stops at t = t9.

  Thus, in the lead battery charge control device 100 according to the present embodiment, when the lead battery 40 is being charged when the vehicle starts to decelerate, the charge is switched to discharge and discharged for a short time, and the charge history is recorded. Eliminate. As a result, when the vehicle is decelerated and fuel cut occurs, charging can be performed with the maximum receiving efficiency, and the efficiency of regenerative charging can be maximized to improve fuel efficiency.

  Next, in the lead battery charge control device 100 according to the present embodiment, control in a mode in which the lead battery 40 is not discharged for a short time before the regenerative charge is started will be described.

  As described above, in the regenerative charge control by the lead battery charge control device 100 according to the present embodiment, the discharge is performed for a short time in order to improve the charge acceptability of the regenerative charge at the time of the fail cut. On the contrary, the meaning of the short-time discharge performed when the vehicle is decelerated is lost.

  Therefore, in the lead battery charge control device 100 according to the present embodiment and the lead battery charge control method using the same, the charge control described below is also performed.

  FIG. 3 is a diagram illustrating an example of changes in the vehicle speed and the SOC with respect to time when the vehicle travels in a state where the vehicle speed V does not exceed the vehicle speed threshold value Vth.

  In FIG. 3, as in FIG. 2, the horizontal axis represents time t (s), and the vertical axis represents vehicle speed V (km / h) and SOC (%), and the vehicle speed V is shown until time t = t3. 2 is different in that the vehicle speed V is constant at V3 at t = t4a and a constant speed lower than the vehicle speed threshold Vth is maintained until t = t5a. The vehicle decelerates from t = t5a and the vehicle speed decreases at a constant rate, and the vehicle stops at t = t9.

  At this time, the change in SOC is the same as in FIG. 2 in that charging starts at t = t2, but even if the vehicle starts decelerating at t = t5a, regenerative charging is performed without discharging for a short time. It shows the changes made. This is because, when the vehicle starts to decelerate, when the vehicle speed is equal to or lower than a certain speed, for example, 20 (km / h) or less, the fail cut time is short. This is because the control for starting the regenerative charging is performed without any change.

  In addition, although the case where the vehicle speed threshold Vth was 20 (km / h) was mentioned as an example, according to the kind and form of the lead battery 40 and a vehicle, you may set to an appropriate value suitably.

  As described above, the lead battery charge control device 100 according to this embodiment performs the regenerative charge of the lead battery 40 without discharging for a short time when the vehicle speed V when the vehicle is decelerated is below a certain value. Thus, it is possible to prevent a state in which the time for regenerative charging is reduced by discharging and the charging efficiency is lowered.

  Next, the aspect of charge control when the vehicle suddenly brakes will be described with reference to FIG. FIG. 4 is a diagram showing the relationship between time t, vehicle speed V, and SOC when the vehicle suddenly brakes.

  In FIG. 4, until time t = t5, the same change as the change in vehicle speed V and SOC shown in FIG. 2 is shown. However, during the period from time t = t5 to t = t9a, the vehicle speed V suddenly decelerates from V = V2 to V = 0, indicating a state change in which the vehicle suddenly brakes. Is different. At this time, the SOC was normally charged between t = t2 and t = t5. However, even after t = t5 where sudden braking occurred, the SOC shifted to regenerative charging without discharging for a short time. It shows a change. As can be seen from the change in vehicle speed and the passage of time shown at t = t5 to t9a in FIG. 4, the regenerative region (t = t5 to t7a) is extremely short in the case of sudden braking. This is because there is not enough time to perform the charging, and the charging efficiency is better if the regenerative charging is performed immediately. For example, if the regenerative region (t = t5 to t7a) itself has only about 5 seconds, there is a possibility that if the discharge for 2 seconds is performed, the remaining is only about 3 seconds, so that sufficient regenerative charging time cannot be secured, and the discharge has an adverse effect. There is a risk of becoming. Therefore, in the case of sudden braking, discharging before the start of regenerative charging is not performed.

  Thus, in the lead battery charging device 100 according to the present embodiment, when the vehicle suddenly brakes, the regenerative charging may be immediately performed without discharging the lead battery 40 for a short time. . Thereby, even in the case of sudden braking, the regenerative charging efficiency under the state can be maximized.

  Next, a control mode when the lead battery 40 is in a discharged state when the vehicle is decelerated will be described with reference to FIG.

  FIG. 5 is a diagram showing the time change of the vehicle speed V and the SOC as in FIG. 2, and the time change of the vehicle speed V shows the same change as in FIG. 2. On the other hand, unlike the embodiment of FIG. 2, the SOC is not charged at all from t = 0 to t = t5 and is continuously discharged. Then, from t = t5, the vehicle decelerates and the vehicle speed starts to decrease. At this time, the SOC is not changed for a short time, but is changed as it is charged. This is because the lead battery 40 is in a discharged state before deceleration of the vehicle and is in a state free from adverse effects due to charge polarization, and therefore it is not necessary to perform a discharge to eliminate the charge history when starting regenerative charging. . In such a case, regenerative charging can be started immediately without discharging for a short time.

  In the regenerative region from t = t5 to t7, charging of the lead battery 40 continues, and when t = t8, the regenerative charge is finished and switched to discharge. Then, the vehicle stops at t = t9, and regenerative charging has already ended at t = t8.

  As described above, the lead battery charge control device 100 according to the present embodiment starts the regenerative charge immediately without discharging for a short time when the lead battery 40 is discharging at the start of deceleration of the vehicle. May be performed. Thereby, execution of useless short-time discharge can be prevented and the efficiency of regenerative charging can be increased.

  In addition, in FIG. 5, although the discharge time of the lead battery 40 was ensured enough, the lead battery 40 was discharging at the time of the deceleration start of a vehicle, for example, but the electric current integration by the discharge time or discharge When the amount is small, the short-time discharge may be performed for a shorter time than the normal short-time discharge, and then charge control may be performed to start regenerative charging. As a result, when there is not enough discharge and a little charging history remains, the charging history can be completely eliminated and the acceptability of the lead battery 40 can be sufficiently increased, so that the regenerative charging can be performed. It can be raised enough. Therefore, in the charging control according to the present embodiment, the control is performed based not only on whether the lead battery 40 is being charged or discharged at the start of deceleration of the vehicle, but also based on a value indicating a charging history such as an accumulated current amount. You may make it perform. Thereby, it is possible to perform charge control more finely and appropriately.

  Moreover, in FIG. 5, although the example of the aspect which did not include the process of charging from t = 0 and was continuously discharged was given, even if it was charged, if sufficient discharge was made after that, Needless to say, as in this embodiment, control may be performed to immediately start regenerative charging when vehicle deceleration starts.

  2 to 5, the state of charge of the lead battery 40 has been described using an aspect of controlling with the SOC. However, the state of charge is expressed and controlled using other index values such as an integrated current value. An index value indicating an appropriate state of charge may be used as appropriate.

  Next, the processing flow of the lead battery charge control method including the modes of FIGS. 2 to 5 using the lead battery charge control device 100 according to the present embodiment will be described.

  FIG. 6 is a control processing flowchart of the lead battery charge control device 100 according to the present embodiment. In addition, about the component similar to demonstrated so far, the same referential mark is attached | subjected and the description is abbreviate | omitted.

  In step 100, it is confirmed that the lead battery 40 is not deteriorated. In the lead battery charge control device 100 according to the present embodiment, since the charge polarization by short-time discharge is eliminated, if the lead battery 40 itself is deteriorated, the discharge or the like may be adversely affected. It is confirmed that the battery 40 is not deteriorated. Various methods may be applied to confirm that the lead battery 40 is not deteriorated. For example, the voltage sensor 12 detects the voltage at the time of cranking, and the deterioration is determined by the charging normal state detection means 10 from this. May be. In addition, an appropriate battery deterioration monitoring device may be used.

  In step 110, the vehicle starts to decelerate. Since the lead battery charging control apparatus 100 according to the present embodiment aims to efficiently perform regenerative charging, the charging control according to the present embodiment is applied when the vehicle is decelerated. Therefore, deceleration of the vehicle is necessary to perform regenerative charging. The deceleration of the vehicle may be detected by the vehicle speed sensor 21, may be detected by the acceleration sensor 22, or both may be used. In addition, if it can be estimated from the position of the brake pedal, etc., they may also be used.

  In step 120, it is confirmed whether or not the SOC of the lead battery 40 exceeds the target SOC. In the lead battery charge control apparatus 100 according to the present embodiment, since the discharge is performed at the start of regenerative charge, it is necessary that the SOC has a certain margin. Therefore, it is confirmed in this step that the charging control can be applied. The SOC may be calculated by the charge state detection means 10 based on the integrated current value detected by the current sensor 11 or the like.

  In step 130, the sudden braking determination means 20 determines whether or not the vehicle speed V exceeds a certain value Vth and whether or not the acceleration a is greater than a certain value α. When the vehicle speed V is equal to or lower than the predetermined value Vth, if the battery is discharged for a short time before the regenerative charging of the lead battery 40, the regenerative charging may be hindered. To do. Similarly, when the acceleration a is below a certain value, the negative acceleration (deceleration) is large and there is a possibility of sudden braking. If discharging is performed before regenerative charging is started, there is a risk that sufficient time for regenerative charging cannot be secured. In order to prevent this, it is determined whether or not the acceleration a is larger than a certain value. The relationship between the vehicle speed V and the acceleration a may be such that the speed only condition is applied first, then the acceleration condition is applied, or both conditions are applied as the and condition from the beginning. Alternatively, the determination may be made using expressions such as the functions of both. By this step, it is determined whether to apply the embodiment of FIG. 3 and the embodiment of FIG.

  The vehicle speed V may be detected by the vehicle speed sensor 21, and the acceleration a may be detected by the acceleration sensor 22. Based on these detection values, whether or not the vehicle is suddenly braked is determined by the sudden braking determination means 20. It may be determined.

  If the vehicle speed V and / or acceleration a is less than the predetermined value in step 130, either the vehicle speed V is insufficient or the brake is suddenly applied, so the routine proceeds to step 160 and regenerative charging is immediately performed. Do.

  On the other hand, when the vehicle speed V is larger than a certain value and the acceleration a is larger than the certain value in step 130, the process proceeds to step 140 when the vehicle is not running at a low speed or not being suddenly braked.

  In step 140, it is determined whether the lead battery 40 has a charging history before the vehicle is decelerated. The presence or absence of the charge history of the lead battery 40 can be determined, for example, based on the accumulated charge / discharge current amount detected by the current sensor 11 when the vehicle decelerates. For example, the charge history of the lead battery 40 may be determined by the charge state detection means 10 based on the accumulated charge / discharge current amount, or may be determined by the charge control device 30.

  If there is no charge history before deceleration, no charge polarization has occurred in the lead battery 40, so the routine proceeds to step 160 and regenerative charging is performed immediately. The control mode is the same as that described in FIG.

  On the other hand, if there is a charging history before deceleration, the process proceeds to step 150.

  In step 150, the lead battery 40 is discharged until it is confirmed that the integrated discharge current value is equal to or greater than a certain value. Thereby, the charge polarization of the lead battery 40 can be eliminated and the charge acceptability can be improved. The discharge current integrated value may be detected by the current sensor 11 and the charge state detection unit 10, and the charge state control unit 30 may perform discharge control of the lead battery 40 based on the detected value.

  When step 150 ends, the process proceeds to step 160 where regenerative charging is performed. The regenerative charging performed in step 160 can be performed in a highly acceptable state with very little charge polarization through this control processing flow. The regenerative charging may be performed by instructing the power generation voltage to the regulator 51 by the charge control means 30 and controlling the alternator 50 based on this instruction.

  Thus, according to the control processing flow by the lead battery charge control device 100 according to the present embodiment, the charge history of the lead battery 40 is eliminated while taking various situations into consideration, and the lead battery 40 is received while adapting to the situation. Can increase the sex. And the efficiency of the regenerative charge at the time of a fail cut can be maximized, and it can contribute to a fuel consumption improvement.

  In addition, when performing lead battery charge control by the lead battery control device 100 according to the present embodiment, when it is confirmed that the lead battery 40 is not in a deteriorated state and the charge acceptance amount with respect to time is low during deceleration regeneration, It can also be determined that the current SOC is higher than the target SOC, and the target SOC can be lowered to improve the acceptability. The low acceptability even though it is not in a deteriorated state is considered to be a state in which the charge receiving capacity is low, and since the lead battery 40 is not in a deteriorated state, even if the target SOC is lowered, the life is reached when the discharge amount is large. This is because it is difficult to consider an adverse effect on the lead battery 40 such as causing a decrease.

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

It is a functional block diagram of lead battery charge control device 100 concerning this example. It is the figure which showed an example of relationship with passage of time, a vehicle speed, and SOC. It is the figure which showed the example of the change of the vehicle speed and SOC with respect to time when the vehicle speed V is less than the vehicle speed threshold value Vth. It is the figure which showed the relationship between time t when a vehicle brakes suddenly, vehicle speed V, and SOC. It is the figure shown about the example of the time change of the vehicle speed V and SOC different from FIG. It is a control processing flow figure of lead battery charge control device 100 concerning this example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Charging state detection means 11 Current sensor 12 Voltage sensor 13 Temperature sensor 20 Rapid braking determination means 21 Vehicle speed sensor 22 Acceleration sensor 30 Charging state control means 40 Lead battery 50 Alternator 51 Regulator 60 Electric load 100 Lead battery charge control device

Claims (6)

A lead battery charging control device for controlling regenerative charging of a lead battery mounted on a vehicle,
Charge state detection means for detecting a charge state of the lead battery;
Charge control means for performing charge control of the lead battery based on the charge state detected by the charge state detection means;
The charging control means starts the regenerative charging after discharging the lead battery for a short time when the charge state detecting means detects that the lead battery is being charged at the start of deceleration of the vehicle. A rechargeable battery charge control device that performs regenerative charge control. The charge state detection means detects the charge state based on the SOC of the lead battery,
The lead battery charge control device according to claim 1, wherein the charge control unit performs the regenerative charge control when the SOC is equal to or greater than a predetermined target SOC value. A vehicle speed sensor,
The charge control means starts the regenerative charge of the lead battery without performing the short-time discharge when the vehicle speed detected by the vehicle speed sensor is less than a predetermined value. The lead battery charge control apparatus of description. An acceleration sensor;
The vehicle further comprises: a vehicle speed detected by the vehicle speed sensor; and a sudden braking detection means for detecting sudden braking of the vehicle based on the acceleration detected by the acceleration sensor.
The charging control means starts the regenerative charging of the lead battery without discharging for a short time when the sudden braking detecting means determines that the vehicle is suddenly braking. The lead battery charge control device according to claim 3. At the start of deceleration of the vehicle, when it is detected by the charge state detection means that the lead battery is being discharged,
5. The lead battery charge control device according to claim 1, wherein the charge control unit starts the regenerative charge of the lead battery without performing the short-time discharge. 6. A lead battery charging control method for controlling regenerative charging of a lead battery mounted on a vehicle,
When the vehicle is decelerated, the charge state of the lead battery is detected,
When the lead battery is being charged according to the detected charging state, the regenerative charging is started after the lead battery is discharged for a short time.

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