JP6233282B2 - Charger - Google Patents

Description

  The present invention relates to a charging device mounted on a vehicle such as an automobile, and more particularly to a technical field of a charging device including two different types of batteries.

  As this type of device, for example, a lead battery directly electrically connected to the alternator and a lithium ion battery electrically connected to the alternator via a DC / DC converter, the field coil of the alternator is provided. An apparatus has been proposed in which charging of a lithium ion battery is prohibited when the energization duty is greater than or equal to a predetermined value, and charging of the lithium ion battery is permitted when the energization duty is less than the predetermined value (patent). Reference 1).

JP 2004-229478 A

  However, according to the above-mentioned background art, when the frequency at which the energization duty becomes equal to or higher than the predetermined value is relatively high, charging of the lithium ion battery is relatively prohibited, and the storage amount of the lithium ion battery is reduced. There is a technical problem that it may continue.

  This invention is made | formed in view of the said problem, for example, and makes it a subject to provide the charging device which can charge two batteries appropriately.

  In order to solve the above problems, a charging device according to the present invention includes a first battery electrically connected to a generator, and a first battery electrically connected to the generator and the first battery via a switch. A battery storage ratio acquisition means for acquiring a power storage ratio that is a ratio of the power storage amount of the second battery to the total capacity; and (i) deceleration of a vehicle on which the battery charger is mounted Sometimes the switch is turned off on the condition that the acquired power storage ratio is greater than or equal to a first threshold, and (ii) when the vehicle is decelerated, the acquired power storage ratio is less than the first threshold and the The switch is turned off on the condition that it is greater than or equal to a second threshold value that is less than the first threshold value, and the current-carrying duty of the field coil of the generator is greater than or equal to a first predetermined value, and (iii) reducing the vehicle Sometimes, the switch is turned on, provided that the acquired storage ratio is less than the first threshold and greater than or equal to the second threshold, and the energization duty is less than the first predetermined value, and (iv) When the vehicle is decelerated, the acquired power storage ratio is less than the second threshold and greater than or equal to a third threshold that is less than the second threshold, and the energization duty is equal to the first predetermined value or the first On the condition that the charging current of the first battery is equal to or greater than a predetermined current value that is a value that is lower than a predetermined value, and (v) when the vehicle is decelerated, Control means for turning on the switch on condition that the acquired power storage ratio is less than the third threshold value.

  According to the charging device of the present invention, the charging device includes a first battery, a second battery, a power storage ratio acquisition unit, and a control unit.

  The first battery is directly electrically connected to the generator. The second battery is electrically connected to each of the generator and the first battery via a switch. The “generator” may be a generator realized in a motor / generator (motor generator). That is, as long as it can function as a generator, it may mean a motor / generator used in, for example, a hybrid vehicle.

  For example, a storage ratio acquisition unit including a memory, a processor, and the like acquires a storage ratio (for example, SOC: State of Charge) of the second battery. In addition, since various well-known aspects are applicable to the acquisition method of an electrical storage ratio, the description about the detail is omitted.

  For example, a control unit including a memory, a processor, and the like turns off the switch on the condition that the acquired power storage ratio is equal to or higher than the first threshold when the vehicle on which the charging device is mounted is decelerated. As a result, since the second battery is electrically disconnected from the generator, the regenerative power generated by the generator accompanying the deceleration of the vehicle is not supplied to the second battery, and deterioration of the second battery can be avoided. .

  The “first threshold value” is a value that determines whether or not the switch is turned off, and is set in advance as a fixed value or a variable value according to some physical quantity or parameter. The “first threshold value” is obtained by calculating a power storage ratio at which deterioration exceeding an allowable degree of deterioration can occur when the second battery is charged experimentally, empirically, or by simulation, for example. What is necessary is just to set as an electrical storage ratio or a value smaller than the calculated | required electrical storage ratio by predetermined value.

  The control means switches on the condition that, when the vehicle decelerates, the acquired power storage ratio is less than the first threshold and greater than or equal to the second threshold, and the energization duty of the field coil of the generator is greater than or equal to the first predetermined value. Is turned off.

  Here, when the energization duty is sufficiently high, it has been found by the inventor's research that a sufficient fuel efficiency improvement effect can be expected simply by charging the first battery with the power of the regenerative power generation of the generator.

  Therefore, even when the second battery can be charged (that is, when the power storage ratio is less than the first threshold and greater than or equal to the second threshold), the energization duty is greater than or equal to the first predetermined value that is relatively high. Is switched off. As a result, it is possible to achieve both improvement in fuel consumption and suppression of deterioration of the second battery.

  The control means turns on the switch when the vehicle is decelerated, on the condition that the acquired power storage ratio is less than the first threshold and greater than or equal to the second threshold, and the energization duty is less than the first predetermined value. That is, when it is estimated that the power generation capacity of the generator has surplus capacity, the first battery and the second battery are charged by the regenerative power generated by the generator accompanying the deceleration of the vehicle, so that the fuel consumption can be improved. it can.

  When the vehicle is decelerated, the control means is configured such that the acquired power storage ratio is less than the second threshold and greater than or equal to the third threshold, the energization duty is greater than or equal to the second predetermined value, and the charging current of the first battery is greater than or equal to the predetermined current value The switch is turned off on the condition that it exists.

  Here, in the present invention, for example, a power converter such as a DC / DC converter is not interposed between the generator and the second battery. For this reason, when charging the second battery, it is necessary to set the power generation voltage of the generator and the charging current of the second battery to values suitable for the second battery in order to suppress the deterioration of the second battery. is there. On the other hand, as a result of setting the power generation voltage of the generator to a voltage suitable for the second battery, the charging current of the first battery may be reduced.

  Therefore, even when the second battery is in a chargeable state and the energization duty is relatively high, the power generation capability of the generator has some margin (that is, when the energization duty is equal to or greater than the second predetermined value). When the charging current of the battery is equal to or greater than a relatively large predetermined current value, the switch is turned off to improve fuel consumption.

  Here, the “predetermined current value” is obtained experimentally, empirically, or by simulation, for example, when the charging current of the first battery is set to a relatively large first value and only the first battery is charged. The fuel efficiency improvement effect obtained when the charging current of the first battery is changed from the first value to a second value smaller than the first value to charge the first battery and the second battery. The fuel efficiency improvement effect obtained when the first battery and the second battery are charged is better than the fuel efficiency improvement effect obtained when only the first battery is charged based on the obtained relationship. What is necessary is just to set as a lower limit of the charging current of the 1st battery which becomes larger than this.

  The “third threshold value” is typically set as a power storage ratio that requires or is desirable to charge the second battery. The “second threshold value” is a value between the first threshold value and the third threshold value, and is appropriately set according to, for example, the specification of the charging device.

  The control means turns on the switch when the vehicle is decelerated on the condition that the acquired power storage ratio is less than the third threshold value. As a result, when the storage amount of the second battery is relatively small, the second battery can be charged to secure the storage amount of the second battery.

  As a result, according to the charging device of the present invention, it is possible to appropriately charge the two batteries while improving the fuel consumption.

  The effect | action and other gain of this invention are clarified from the form for implementing demonstrated below.

It is a schematic block diagram which shows the outline | summary of the charging device which concerns on 1st Embodiment. It is a flowchart which shows the charge control process which concerns on 1st Embodiment. It is a time chart which shows a specific example of the charge control process which concerns on 1st Embodiment. It is a flowchart which shows the charge control process which concerns on 2nd Embodiment. It is a key map showing the concept of switch control concerning a 3rd embodiment. It is a flowchart which shows the charge control process which concerns on 3rd Embodiment.

  An embodiment according to a charging device of the present invention will be described with reference to the drawings.

<First Embodiment>
1st Embodiment which concerns on the charging device of this invention is described with reference to FIG.

(Configuration of charging device)
First, the structure of the charging device according to the first embodiment will be described with reference to FIG. FIG. 1 is a schematic configuration diagram illustrating an overview of the charging apparatus according to the first embodiment. The charging device is mounted on a vehicle such as an automobile.

  In FIG. 1, a charging device 100 includes an alternator 11, a lead battery 12, a second battery 13 that is a nickel metal hydride battery or a lithium ion battery, and an ECU (Electronic Control Unit) 14. ing. The second battery 13 is electrically connected to the alternator 11 and the lead battery 12 via the switches SW1 and SW2.

  A starter motor of a vehicle in which the charging apparatus 100 is mounted, and auxiliary equipment such as a water pump, a wiper, and a light are operated by electric power supplied from at least one of the alternator 11, the lead battery 12, and the second battery 13. To do. Note that the ECU 14 is also electrically connected to the alternator 11, the lead battery 12, and the second battery 13, but for convenience of explanation, the description is as shown in FIG.

  The alternator 11 has, for example, a stator coil wound around the stator as a three-phase coil and a field coil wound around the rotor, rectifies and outputs a three-phase alternating current output from the stator coil, and a switching circuit. It is a generator with a regulator which incorporated the IC regulator comprised by this.

  The IC regulator has a function for maintaining the voltage generated by the alternator 11 constant. Specifically, when the voltage generated by the alternator 11 is smaller than the target voltage related to the command signal from the ECU 14, the IC regulator causes the exciting current to flow through the field coil by turning on the switching circuit. A three-phase alternating current is generated in the stator coil. On the other hand, when the voltage generated by the alternator 11 is higher than the target voltage, the switching circuit is turned off to stop the supply of the excitation current to the field coil and to stop the stator coil from generating the current. Due to such an IC regulator function, the voltage generated by the alternator 11 is maintained at the target voltage.

  The ECU 14 is electrically connected to the contact point between the field coil of the alternator 11 and the IC regulator. When the switching circuit of the IC regulator is turned on, an on signal indicating the energization state of the field coil, that is, the power generation state of the alternator 11 is supplied to the ECU 14. When the switching circuit of the IC regulator is turned off, an off signal indicating the non-energized state of the field coil, that is, the non-power generating state of the alternator 11 is supplied to the ECU 14.

  The ECU 14 is an on / off ratio per cycle time of the alternator 11 based on an on / off signal supplied from the field coil of the alternator 11, specifically, a ratio of the on time within one cycle time. The energization duty is detected. This energization duty indicates the ratio of the power generation amount that is actually generated with respect to the maximum power generation amount that the alternator 11 can generate based on the current engine speed and the like.

(Operation of the charging device)
Next, the operation of the charging apparatus 100 configured as described above will be described with reference to the flowchart of FIG.

  In FIG. 2, when deceleration of the vehicle on which the charging device 100 is mounted is started, the ECU 14 turns off at least one of the switches SW <b> 1 and SW <b> 2 to move the second battery 13 from the alternator 11 and the lead battery 12. Disconnect electrically (step S101).

  Next, the ECU 14 determines whether or not the energization duty of the field coil of the alternator 11 (hereinafter referred to as “field duty” as appropriate) is equal to or greater than a predetermined value (step S102). Here, the “predetermined value” related to the processing in step S102 is set as an upper limit value of the field duty estimated that the alternator 11 has sufficient power generation surplus, for example.

  When it is determined that the field duty is greater than or equal to the predetermined value (that is, when it is determined that the power generation surplus of the alternator 11 is small or not) (step S102: Yes), the ECU 14 turns off at least one of the switches SW1 and SW2. The state is maintained (step S103). If comprised in this way, in order to charge the 2nd battery 13, for example, it can avoid that the lead battery 12 discharges.

  After the process of step S103, the ECU 14 determines whether or not the vehicle has been decelerated (step S104). When it is determined that deceleration of the vehicle has ended (step S104: Yes), the ECU 14 ends the process once. On the other hand, when it is determined that the vehicle is decelerating (step S104: No), the ECU 14 performs the process of step S102 described above.

  When it is determined in the process of step S102 described above that the field duty is less than the predetermined value (that is, when it is determined that there is sufficient power generation capacity of the alternator 11) (step S102: No), the ECU 14 SW1 and SW2 are turned on, and the second battery 13 is electrically connected to the alternator 11 and the lead battery 12 (step S105).

  Next, ECU14 determines whether the charging current of the 2nd battery 13 is below a predetermined value (step S106). Here, the “predetermined value” related to the process of step S106 is set as an upper limit value of a current value range that does not cause deterioration of the second battery 13 due to charging, for example.

  When it is determined that the charging current of the second battery 13 is equal to or less than the predetermined value (step S106: Yes), the ECU 14 performs the process of step S104 described above. If comprised in this way, deterioration of the 2nd battery 13 can be suppressed, aiming at the improvement of a fuel consumption by charging the lead battery 12 and the 2nd battery 13. FIG.

  On the other hand, when it is determined that the charging current of the second battery 13 is larger than the predetermined value (step S106: No), the ECU 14 limits the power generation amount of the alternator 11 so that the charging current of the second battery 13 decreases. (Step S107), the process of step S106 is performed. If comprised in this way, it can suppress that the 2nd battery 13 originates in charge of the 2nd battery 13, and deteriorates.

  Next, the operation of the charging apparatus 100 will be described with reference to the time chart of FIG. In the graph of “battery charging current” in FIG. 3, the solid line indicates the charging current of the lead battery 12 (main battery), and the broken line indicates the charging current of the second battery 13 (sub-battery). .

  When the vehicle starts decelerating at time t1 in FIG. 3, the ECU 14 turns off at least one of the switches SW1 and SW2 by the process in step S101 described above (see the “sub battery switch” graph in FIG. 3). .

  In the period from time t1 to time t2, since the field duty of the alternator 11 is equal to or greater than a threshold value (corresponding to the predetermined value in the process of step S102 described above), the ECU 14 maintains at least one of the switches SW1 and SW2 in the off state. .

  When deceleration of the vehicle ends at time t2, ECU 14 turns on switches SW1 and SW2.

  When the vehicle starts to decelerate again at time t3, the ECU 14 turns off at least one of the switches SW1 and SW2. When the field duty of the alternator 11 falls below a predetermined value at time t4, the ECU 14 turns on the switches SW1 and SW2 by the process of step S105 described above. As a result, charging of the second battery 13 is started, and accordingly, the field duty of the alternator 11 also increases (see the “alternator field duty” graph in FIG. 3).

  When the deceleration of the vehicle is completed at time t5, the ECU 14 maintains the switches SW1 and SW2 on.

  Here, according to the inventor's research, the following matters have been found. That is, for example, a nickel metal hydride battery or a lithium ion battery as the second battery 13 is more expensive than the lead battery 12 although it is excellent in durability. For this reason, replacement of the second battery 13 is not desirable, and it is necessary to suppress the progress of deterioration of the second battery 13. The second battery 13 also functions as a backup power source when, for example, the switch SW1 in FIG. 1 is turned off and the switch SW2 is turned on. For this reason, a situation where the backup function is lost due to deterioration of the second battery 13 must be avoided.

  In the charging apparatus 100 according to the present embodiment, as described above, when the power generation surplus of the alternator 11 is small (that is, when the field duty is greater than or equal to a predetermined value), only the lead battery 12 is charged, whereby the second battery 13 deterioration can be prevented. Further, even when the lead battery 12 and the second battery 13 are charged when the power generation surplus of the alternator 11 is relatively large, the second battery 13 can be charged by limiting the charging current value. The fuel consumption is improved while suppressing the deterioration of the battery 13. As described above, the charging device 100 according to the present embodiment can achieve both suppression of deterioration of the second battery 13 and improvement of fuel consumption.

Second Embodiment
A second embodiment of the charging device of the present invention will be described with reference to the flowchart of FIG. The second embodiment is the same as the first embodiment described above except that part of the charge control process is different. Therefore, in the second embodiment, the description overlapping with that of the first embodiment is omitted, and the common portions in the drawing are denoted by the same reference numerals, and only fundamentally different points are described with reference to FIG. explain.

  In the flowchart of FIG. 4, when it is determined that the field duty is greater than or equal to a predetermined value in the process of step S102 described above (see FIG. 2) (step S102: Yes), the ECU 14 determines that the charging current of the lead battery 12 is predetermined. It is determined whether or not the value is greater than or equal to the value (step S201).

  Here, the “predetermined value” related to the process of step S201 is set as an upper limit value of the charging current that causes the degree of deterioration of the second battery 13 to be within an allowable range when the second battery 13 is charged, for example. ing.

  When it is determined that the charging current of the lead battery 12 is equal to or greater than the predetermined value (step S201: Yes), the ECU 14 maintains at least one of the switches SW1 and SW2 in an off state.

  On the other hand, when it is determined that the charging current of the lead battery 12 is less than the predetermined value (step S201: No), the ECU 14 turns on the switches SW1 and SW2, turns the second battery 13 into the alternator 11 and the lead battery 12. Are electrically connected to each other (step S202).

  It has been found that when the charging current flowing through the second battery 13 is relatively small, the degree of deterioration of the second battery 13 is small. For this reason, even when the power generation surplus of the alternator 11 is small, when the charging current is relatively small, the charged amount of the second battery 13 is ensured by positively charging the second battery 13. In addition, the fuel consumption can be improved.

  Therefore, according to the charging apparatus 100 according to the present embodiment, even when the frequency at which the field duty is equal to or higher than the predetermined value is relatively high, the deterioration of the second battery 13 is suppressed and the second battery 13 is suppressed. The amount of stored electricity can be secured.

<Third Embodiment>
A third embodiment according to the charging device of the present invention will be described with reference to FIGS. 5 and 6. The third embodiment is the same as the first embodiment described above except that part of the charge control process is different. Accordingly, the description of the third embodiment that is the same as that of the first embodiment is omitted, and common portions in the drawings are denoted by the same reference numerals, and only the differences are basically illustrated in FIGS. 5 and 6. The description will be given with reference.

  In the first embodiment described above, on / off of the switches SW1 and SW2 is determined depending on whether or not the field duty of the alternator 11 is greater than or equal to a predetermined value. In the present embodiment, the switches SW1 and SW2 are turned on / off in consideration of the SOC of the second battery 13 in addition to the field duty of the alternator 11.

Specifically, as shown in FIG. 5, when the SOC of the second battery 13 is less than SOC ₁ , for example, an SOC that needs to be charged or is desirable to charge the second battery 13, the field Regardless of the duty, the switches SW1 and SW2 are turned on.

When the SOC of the second battery 13 is, for example, SOC ₃ or more, which is a SOC that may cause deterioration exceeding an allowable degree of deterioration when the second battery is charged, the switch is used regardless of the field duty. At least one of SW1 and SW2 is turned off.

The SOC of the second battery 13 is a value between SOC ₁ and SOC _3, and is, for example, an upper limit value of SOC estimated to have a relatively large storage capacity of the second battery 13, less than SOC ₂ , and In the case of SOC ₁ or more, on / off of the switches SW1 and SW2 is determined according to the field duty and the charging current of the lead battery 12.

When the SOC of the second battery 13 is SOC ₂ or more and less than SOC ₃ , ON / OFF of the switches SW1 and SW2 is determined according to the field duty.

  Next, the charging control process according to the present embodiment will be described with reference to the flowchart of FIG.

  In FIG. 6, when deceleration of the vehicle on which the charging device 100 is mounted is started, the ECU 14 turns off at least one of the switches SW <b> 1 and SW <b> 2 to move the second battery 13 from the alternator 11 and the lead battery 12. Disconnect electrically (step S301).

Next, the ECU 14 obtains an SOC _sub that is the current SOC of the second battery 13 (step S302). Subsequently, the ECU 14 determines whether or not the acquired SOC _sub is SOC ₃ or more (step S303).

When it is determined that the obtained SOC _sub is SOC ₃ or higher (step S303: Yes), the ECU 14 determines that the remaining power of the second battery 13 is small or not, and at least one of the switches SW1 and SW2 is turned off. Is maintained (step S304).

  Next, the ECU 14 determines whether or not the deceleration of the vehicle has ended (step S305). When it is determined that the deceleration of the vehicle has ended (step S305: Yes), the ECU 14 ends the process once. On the other hand, when it is determined that the vehicle is decelerating (step S305: No), the ECU 14 performs the process of step S302 described above.

In the process of step S303 described above, when it is determined that the acquired SOC _sub is less than SOC ₃ (step S303: No), the ECU 14 acquires the field duty Fd of the alternator 11 (step S306). Subsequently, the ECU 14 determines whether or not the acquired SOC _sub is SOC ₂ or higher (step S307).

When it is determined that the acquired SOC _sub is greater than or equal to SOC ₂ (step S307: Yes), the ECU 14 determines whether or not the acquired field duty Fd is greater than or equal to a predetermined value Fd ₁ (step S307). S308). Here, the predetermined value Fd ₁ is set as an upper limit value of the field duty estimated that the alternator 11 has sufficient power generation capacity, for example.

When it is determined that the acquired field duty Fd is equal to or greater than the predetermined value Fd ₁ (step S308: Yes), the ECU 14 determines that the power generation surplus of the alternator 11 is small or not, and turns off at least one of the switches SW1 and SW2. The state is maintained (step S304).

On the other hand, when it is determined that the acquired field duty Fd is less than the predetermined value Fd ₁ (step S308: No), the ECU 14 turns on the switches SW1 and SW2 to connect the second battery 13 to the alternator 11 and The lead battery 12 is electrically connected (step S309).

Next, the ECU 14 acquires the charging current I _{b_sub} of the second battery 13 (step S310). Subsequently, the ECU 14 determines whether or not the acquired charging current I _{b_sub} is equal to or less than a predetermined value I _b1 (step S311). Here, the predetermined value _Ib1 is set as an upper limit value of a current value range that does not cause deterioration of the second battery 13 due to charging, for example.

When it is determined that the acquired charging current I _{b_sub} is equal to or less than the predetermined value I _b1 (step S311: Yes), the ECU 14 performs the process of step S305 described above. On the other hand, when it is determined that the acquired charging current I _{b_sub} is larger than the predetermined value I _b1 (step S311: No), the ECU 14 sets the alternator 11 so that the charging current I _{b_sub} of the second battery 13 decreases. The amount of power generation is limited (step S312), and the process of step S310 is performed.

When it is determined that the acquired SOC _sub is less than SOC ₂ in the process of step S307 described above (step S307: No), the ECU 14 determines whether the acquired SOC _sub is SOC ₃ or more. Is determined (step S313). When it is determined that the obtained SOC _sub is less than SOC ₃ (step S313: No), the ECU 14 turns on the switches SW1 and SW2 on the assumption that the second battery 13 needs to be charged (step S313). S309).

On the other hand, when it is determined that the acquired SOC _sub is SOC ₃ or higher (step S313: Yes), the ECU 14 acquires the charging current _{Ib_main} of the lead battery 12 (step S314). Subsequently, the ECU 14 determines whether or not the acquired field duty Fd is equal to or greater than a predetermined value Fd ₂ (step S315). The predetermined value Fd ₂ is set as somewhat lower than the predetermined value Fd ₁ and equal to or predetermined value Fd ₁ described above.

When it is determined that the acquired field duty Fd is less than the predetermined value Fd ₂ (step S315: No), the ECU 14 sets the switches SW1 and SW2 to the on state, assuming that the alternator 11 has sufficient power generation capacity. (Step S309).

On the other hand, when it is determined that the acquired field duty Fd is greater than or equal to the predetermined value Fd ₂ (step S315: Yes), the ECU 14 determines whether or not the acquired charging current I _{b_main} is greater than or equal to the predetermined value I _b2 . Is determined (step S316). The predetermined value Ib _2, for example when the second battery 13 is charged, is set as the upper limit value of the charging current I _{B_main} the degree of degradation of the second battery 13 is within the allowable range.

If the obtained charging current _{I B_main} is determined to be smaller than the predetermined value _{I b2} (Step S316: No), ECU 14 as the degradation of the second battery 13 is little, the switches SW1 and SW2 turned on (Step S309).

On the other hand, when it is determined that the acquired charging current I _{b_main} is greater than or equal to the predetermined value I _b2 (step S316: Yes), the ECU 14 switches the switches SW1 and SW2 to prevent deterioration due to charging of the second battery 13. At least one of the OFF states is maintained (step S317), and the process of step S305 described above is performed.

  The “alternator 11”, “lead battery 12”, and “second battery 13” according to the present embodiment are examples of the “generator”, “first battery”, and “second battery” according to the present invention, respectively. It is. The “ECU 14” according to the present embodiment is an example of the “charge ratio acquisition unit” and the “control unit” according to the present invention. That is, in the present embodiment, a part of the function of the ECU 14 that performs various electronic controls of the vehicle on which the charging device 100 is mounted is used as a part of the charging device 100.

“SOC ₁ ”, “SOC ₂ ”, “SOC ₃ ”, “predetermined value Fd ₁ ”, “predetermined value Fd ₂ ”, and “predetermined value Ib ₂ ” according to the present embodiment are respectively “ 3 threshold values, “second threshold value”, “first threshold value”, “first predetermined value”, “second predetermined value”, and “predetermined current value”.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification. Moreover, it is included in the technical scope of the present invention.

  DESCRIPTION OF SYMBOLS 11 ... Alternator, 12 ... Lead battery, 13 ... 2nd battery, 14 ... ECU, 100 ... Charging apparatus, SW1, SW2 ... Switch

Claims (1)

A charging device comprising: a first battery electrically connected to a generator; and a second battery electrically connected to the generator and the first battery via a switch,
A power storage ratio acquisition means for acquiring a power storage ratio that is a ratio of a total amount of power stored in the second battery;
(I) When the vehicle on which the charging device is mounted is decelerated, the switch is turned off on the condition that the acquired power storage ratio is greater than or equal to a first threshold, and (ii) when the vehicle decelerates, The switch is provided on the condition that the acquired power storage ratio is less than the first threshold and greater than or equal to a second threshold smaller than the first threshold, and the energization duty of the field coil of the generator is greater than or equal to a first predetermined value. (Iii) When the vehicle is decelerated, the acquired power storage ratio is less than the first threshold and greater than or equal to the second threshold, and the energization duty is less than the first predetermined value. And (iv) when the vehicle is decelerated, the acquired power storage ratio is less than the second threshold value and greater than or equal to a third threshold value that is less than the second threshold value. On the condition that the battery is equal to or higher than the second predetermined value, which is the same value as the first predetermined value or lower than the first predetermined value, and the charging current of the first battery is equal to or higher than the predetermined current value. (V) control means for turning on the switch on condition that the acquired power storage ratio is less than the third threshold when the vehicle is decelerated;
A charging device comprising:

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