JP2006038593A - Battery capacity detection device, and generating set equipped therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To grasp accurately a battery capacity even after the battery is replaced by detecting a full charge capacity of the exchanged battery, and resultantly to prevent excess charge or excess discharge of the battery, and to prevent decline of a battery lifetime. <P>SOLUTION: When battery exchange is detected by a replacement detection part 6, the output voltage V<SB>a</SB>of a generator 3 is set from a voltage agreeing with a terminal open voltage equivalent to the first charging rate P<SB>1</SB>to a voltage agreeing with a terminal open voltage equivalent to the second charging rate P<SB>2</SB>lower than the first charging rate P<SB>1</SB>based on an open voltage characteristic by a discharge control part 52. Then, a controlled discharge amount q<SB>c</SB>during discharge control is calculated, and the full charge capacity Q<SB>f</SB>of the exchanged battery 2b is calculated from the difference between the first charging rate P<SB>1</SB>and the second charging rate P<SB>2</SB>, and the controlled discharge amount q<SB>c</SB>. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a battery capacity detection device and a power generation device including the same.

  2. Description of the Related Art Conventionally, a technique that considers battery capacity when charging a battery is known. One example is the invention disclosed in Patent Document 1.

The battery device disclosed in Patent Document 1 improves the fuel consumption by reducing the output voltage of the generator except during deceleration, and recovers energy by increasing the output voltage of the generator during deceleration. In performing such output voltage change control, overcharging of the battery is prevented by considering the capacity of the battery.
JP-A-5-137275

  By the way, in order to grasp the capacity of the battery, it is necessary to accurately grasp the charge / discharge amount of the battery and the full charge capacity of the battery. Usually, the charge / discharge amount of the battery is calculated by integrating charge / discharge currents from the battery. The full charge capacity of the battery is stored as the full charge capacity of the battery installed at the time of shipment.

  However, since the battery is a consumable item, it is essential to replace it. In this battery replacement, the battery full charge capacity is not necessarily replaced with the same battery as the genuine battery before replacement. There are also machine differences between batteries. In this way, when the full charge capacity is changed before and after the battery replacement, if the battery capacity is detected, the charge / discharge amount of the battery can be accurately calculated, but the full charge capacity of the battery is incorrect. A capacity different from the actual battery capacity is detected. As a result, by performing the above-described output voltage control of the generator based on the erroneously detected battery capacity, the battery may be overcharged or overdischarged repeatedly, thereby promoting battery deterioration.

  The present invention has been made in view of such a point, and the object of the present invention is to detect the full charge capacity of the replaced battery, thereby reducing the capacity of the battery even after the battery is replaced. It is to accurately grasp and as a result, prevent overcharge and overdischarge of the battery and prevent a decrease in battery life.

  According to a first aspect of the present invention, there is provided a current detecting means for detecting a charging / discharging current of a battery mounted on a vehicle and a charging / discharging amount for calculating the charging / discharging amount of the battery by integrating the charging / discharging current detected by the current detecting means. The battery capacity detection device includes discharge amount calculation means and capacity storage means for storing the full charge capacity of the battery.

  And the voltage control means which controls the output voltage of the generator which is driven by the engine and supplies electric power to the battery and the electric load for the vehicle, the exchange detection means for detecting that the battery has been exchanged, and the battery An open-circuit voltage characteristic storage means for storing an open-circuit voltage characteristic that is a relationship between a terminal open-circuit voltage and a charging rate, and a capacity calculation means for calculating a full-charge capacity that is a capacity when the battery is substantially fully charged. It shall be.

  Further, the voltage control means, when battery replacement is detected by the replacement detection means, sets the output voltage of the generator to a predetermined first charging rate based on the open voltage characteristics stored in the open voltage storage means. The battery discharge control is set to a voltage corresponding to the terminal open voltage of the battery corresponding to the second charge rate lower than the first charge rate after being set to a voltage corresponding to the battery terminal open voltage corresponding to The charge / discharge amount calculation means integrates the discharge current detected by the current detection means while the discharge control is being executed by the voltage control means, thereby controlling the amount of control discharge discharged from the battery. The capacity calculation means calculates a full charge capacity of the battery after replacement from the difference between the first charge rate and the second charge rate and the control discharge amount, and the capacity is calculated. Storage means, and adapted to store the full charge capacity of the battery after replacement calculated by the volume calculating means.

  In the case of the above configuration, the battery capacity is detected by adding or subtracting the charge / discharge amount of the battery calculated by the charge / discharge amount calculation means to the full charge capacity of the battery stored in the capacity storage means.

  When the battery is replaced, the replacement detection unit detects the replacement of the battery. Then, the following output control of the output voltage of the generator is performed by the discharge control means of the voltage control means based on the open voltage characteristics of the battery stored in the open voltage storage means. First, the output voltage of the generator is set to a voltage that matches the terminal open voltage of the battery corresponding to the first charging rate. Thus, the battery is in the first charging rate state. Thereafter, the output voltage of the generator is set to a voltage that matches the terminal open voltage of the battery corresponding to the second charging rate. Since the second charging rate is lower than the first charging rate, the battery is forcibly discharged. Thus, the battery is in the second charging rate state. Then, the discharge amount when the battery is discharged from the first charge rate to the second charge rate is calculated as the control discharge amount by the control discharge amount calculating means. This controlled discharge amount corresponds to a capacity difference between the first charging rate and the second charging rate. Therefore, the full charge capacity of the battery after replacement is detected by the capacity detection means from the difference between the first charge rate and the second charge rate and the discharge amount calculated by the control discharge amount calculation means.

  The full charge capacity of the battery after replacement detected by the capacity detection means is stored in the capacity storage means. This capacity storage means stores the full charge capacity of all batteries that are replaced from the genuine battery installed at the time of shipment if the full charge capacity of the latest battery that has been replaced is stored in an available state. Even when the battery is replaced, it may be updated by overwriting the full charge capacity of the battery every time the battery is replaced. Then, the battery capacity detection is performed using the full charge capacity of the battery after replacement stored in the capacity storage means.

  Here, the open circuit voltage characteristic is substantially constant between batteries if the batteries have the same rated voltage. Since the present invention detects the full charge capacity of the battery using this open-circuit voltage characteristic, the full charge capacity of the battery after replacement can be easily and accurately detected even after the battery is replaced. it can.

According to a second aspect of the present invention, there is provided current detection means for detecting a charge / discharge current of a battery mounted on a vehicle,
A battery comprising charge / discharge amount calculation means for calculating the charge / discharge amount of the battery by integrating charge / discharge currents detected by the current detection means, and capacity storage means for storing the full charge capacity of the battery. The capacity detection device is the target.

  And the voltage control means which controls the output voltage of the generator which is driven by the engine and supplies electric power to the battery and the electric load for the vehicle, the exchange detection means for detecting that the battery has been exchanged, and the battery An open-circuit voltage characteristic storage unit that stores an open-circuit voltage characteristic that is a relationship between a terminal open-circuit voltage and a charging rate; a capacity calculation unit that calculates a full-charge capacity that is a capacity when the battery is substantially fully charged; and the current detection And a full charge state determination means for determining a full charge state of the battery based on the charge / discharge current detected by the means.

  The voltage control means is stored in the open voltage storage means after the full charge state determination means determines that the battery is fully charged when battery replacement is detected by the replacement detection means. Based on the open-circuit voltage characteristics, the output voltage of the generator is set to a voltage corresponding to the terminal open-circuit voltage of the battery corresponding to a predetermined charging rate lower than the fully charged state, the battery discharge control is performed, The charge / discharge amount calculation means calculates the control discharge amount discharged from the battery by integrating the discharge current detected by the current detection means while the discharge control is being executed by the voltage control means, The capacity calculation means calculates the full charge capacity of the battery after replacement from the difference between the full charge and the predetermined charge rate and the control discharge amount, and the capacity憶 means shall storing the full charge capacity of the battery after replacement calculated by the volume calculating means.

  That is, the second invention further includes a full charge state determination means in addition to the constituent elements of the first invention, and the first control is performed in the battery discharge control by the voltage control means and the full charge capacity calculation by the capacity calculation means. A process different from that of the invention is performed.

  Specifically, in the case of the above configuration, when the battery is replaced, it is first determined that the battery is fully charged. Then, after determining that the battery is fully charged, discharge control is performed to discharge the battery from full charge to a predetermined charge rate. That is, the battery needs to be in a fully charged state at the start of discharge control. When the battery is not in a fully charged state, charging is first performed until full charging.

  The charge / discharge amount calculation unit calculates a control discharge amount during discharge control for discharging the battery from full charge to a predetermined charge rate, and the capacity calculation unit uses the control discharge amount to fully charge the battery. Calculate capacity.

  By setting the state of charge of the battery that starts the discharge control to the fully charged state, the discharge control is performed near the fully charged state. Usually, the battery is preferably used in the vicinity of the fully charged state, and can be charged to a substantially fully charged state immediately after the discharge control.

  The third invention is directed to a power generation device including the battery capacity detection device according to the first or second invention and a deceleration state detection means for detecting deceleration of the vehicle.

  Based on the detection result of the deceleration state detection means and the full charge capacity of the battery stored in the capacity storage means, when the vehicle is not in the deceleration state, the output voltage of the generator is supplied to the battery. While controlling the output voltage to a second voltage that promotes charging of the battery when the vehicle is in a decelerating state, while controlling the output voltage during deceleration. When the battery replacement is detected by the replacement detection unit, the output voltage control during deceleration is prohibited after the detection until the full charge capacity of the replaced battery is detected by the capacity detection unit. Shall.

  In the case of the above configuration, the power generator controls the output voltage of the generator depending on whether or not the vehicle is decelerating. Specifically, when the deceleration state is detected by the deceleration state detection means, the output voltage of the generator is controlled to the second voltage that can promote the charging of the battery, and energy is actively collected during deceleration. . On the other hand, when the deceleration state is not detected, the output voltage of the generator is controlled to the first voltage that suppresses charging of the battery, that is, the load imposed on the engine by the generator is reduced, thereby improving the fuel consumption.

  Then, after battery replacement is detected by the replacement detection means, the output voltage control is prohibited until the full charge capacity of the battery after replacement is detected by the capacity detection means. The output voltage control is performed based on the full charge capacity of the battery stored in the capacity storage means. Here, when the full charge capacity of all the batteries exchanged from the battery mounted at the time of shipment is stored in the capacity storage means, it goes without saying that the latest full charge capacity of the battery is used. Therefore, if the output voltage control during deceleration is performed after battery replacement and before the full charge capacity of the battery after replacement is detected, the capacity of the battery is detected based on the full charge capacity of the battery before replacement. Overdischarge may occur. For this reason, after the battery is replaced, by prohibiting the output voltage control during deceleration until the full charge capacity of the battery is detected, overcharge and overdischarge based on the incorrect full charge capacity of the battery are prevented.

  According to the first invention, even after the battery is replaced, the full charge capacity of the battery after the replacement can be detected easily and accurately by performing the discharge control of the battery based on the open-circuit voltage characteristics of the battery. it can. As a result, even if a battery with a full charge capacity different from the battery before replacement is installed due to battery replacement, it is possible to accurately detect the capacity of the battery after replacement, thus preventing overcharge and overdischarge of the battery. And a reduction in battery life can be prevented.

  According to the second invention, the same effect as the first invention is achieved, and the discharge control is performed in the vicinity of the fully charged state, so that the battery is in a fully charged state which is a preferable charged state during normal use. Can be charged early after the discharge control.

  According to the third aspect of the invention, the output voltage of the generator is controlled according to whether or not the vehicle is decelerating, so that efficient energy recovery and fuel efficiency can be improved. It is possible to prevent overcharging and overdischarging based on the full charge capacity, and it is possible to prevent a decrease in battery life.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Embodiment 1 of the Invention
FIG. 1 shows a vehicular power generation apparatus 1 according to an embodiment of the present invention. Reference numeral 1a denotes an electric load of the vehicle, such as a starter or a headlamp. Battery reference numeral 2, which is connected to an electrical load 1a, reference numeral 3 is a generator for supplying power and charging of the battery 2 to the driven electric load 1a by the engine, the negative sign 4 controls the output voltage V _a of the generator 3 Controller.

The battery 2 is a lead battery using sulfuric acid as an electrolytic solution, and the terminal open-circuit voltage _Vb in a fully charged state and a stable state of a battery having a rating of 12V is about 12.6V. This terminal open circuit voltage _Vb is proportional to the electrolyte specific gravity, that is, the battery charge rate in a stable state where it is left without being charged and discharged, and has the characteristics shown in FIG. 2 (hereinafter referred to as open circuit voltage characteristics). Terminal open circuit voltage V _b of battery 2 from 12.6V in a fully charged state, decreases as the charging rate decreases. As will be described later, the present invention detects the full charge capacity Q _f of the battery 2 on the premise of the proportional relationship between the terminal open voltage V _b and the charging rate. The battery 2 is connected to the load 1 a and also to the generator 3. In other words, power is supplied (discharged) to the electrical load 1 a while being charged by the generator 3. The charging / discharging current C at this time is detected by a current sensor 21 connected to the battery 2. That is, the charge / discharge amount q of the battery 2 is always detected via the current sensor 21.

The generator 3 is driven by an engine (not shown) to charge the battery 2 and also supply power to a part of the electric load 1a. Output voltage V _a of the generator 3 is a variable, by changing the output voltage V _a, it is possible to set the battery 2 to the desired charging rate. That is, the battery 2, the terminal open circuit voltage V _b of battery 2 is charged and discharged until balance with the output voltage V _a of the generator 3, converges to a charging rate corresponding to the output voltage V _a.

The controller 4, taking into account the running state of the charge state and a battery of the vehicle 2 or the like, and controls the output voltage V _a of the generator 3. Controller 4 sets the output voltage control unit 5 for setting the output voltage V _a of the generator 3, a replacement detection unit 6 that detects that the battery 2 is replaced, the charging rate to be used in the discharge control described later Based on the charge / discharge current C of the battery 2 and the open-circuit voltage characteristic storage unit 8 that stores the open-circuit voltage characteristic that is the relationship between the terminal open-circuit voltage of the battery 2 and the charge rate. A full charge determination unit 9 that determines the state of charge, a charge / discharge amount calculation unit 10 that calculates the charge / discharge amount q by integrating the charge / discharge current C of the battery 2, and a full charge capacity Q _f that detects the full charge capacity Q _f of the battery 2 A charge capacity calculation unit 11; a full charge capacity storage unit 12 for storing the full charge capacity Q _f detected by the full charge capacity calculation unit 11; an engine start detection unit 13 for detecting completion of engine start; Deceleration state detection to detect deceleration state Comprises a section 14, the.

The output voltage control unit 5, while improving fuel economy by reducing the output voltage V _a of the generator 3 is in other than the vehicle deceleration, actively energy by increasing the output voltage V _a of the generator 3 at the time of vehicle deceleration were collected, and the deceleration output voltage control unit 51 for decelerating the output voltage control for charging the battery 2, when the battery 2 is replaced, in order to detect the full charge capacity Q _f of the battery 2b after replacement , and a discharge control unit 52 that performs discharge control for discharging the battery 2b from the predetermined first charging rate P ₁ to a second charging rate P _2. In the first embodiment, the first charging rate is fixed at a substantially fully charged state.

The replacement detection unit 6 is connected to the battery 2 and detects a battery voltage (terminal open voltage) _Vb . Specifically, when the battery voltage _Vb becomes zero, it is determined that the battery 2 has been replaced, and the replacement detection signal p1 is output to the output voltage control unit 5.

The charging rate setting unit 7 receives the arbitrarily selected second charging rate P ₂ and outputs this value to the output voltage control unit 5 and the full charge capacity calculation unit 11. The second charging rate P ₂ may be set at the time of shipment, or may be set or changed by a driver or the like after shipment.

The open-circuit voltage characteristic storage unit 8 stores a table of open-circuit voltage characteristics of the battery 2 shown in FIG. Then, the terminal open voltage corresponding to the second charging rate P ₂ is output to the output voltage controller 5.

The full charge determination unit 9 detects the charge / discharge current C of the battery 2. The charge / discharge current C of the battery 2 varies depending on the state of charge of the battery 2 as shown in FIG. Specifically, as the battery 2 approaches the fully charged state, the charge / discharge current C decreases and converges to a constant value in the fully charged state. Therefore, by observing the charge / discharge current C, it can be determined whether or not the battery 2 is in a fully charged state. Therefore, the full charge determination unit 9 sets the charge / discharge current value in the substantially full charge state as the predetermined value _Cr , and when the charge / discharge current C becomes equal to or less than the predetermined value _Cr , the battery 2 is almost fully charged. It is determined that the state has been reached, and a full charge determination signal p <b> 2 is output to the output voltage control unit 5.

When the battery 2 is replaced and the replacement detection signal p1 is input from the replacement detection unit 6, the discharge control unit 52 in the output voltage control unit 5 performs discharge control. Specifically, first, set the generator 3 of the output voltage V _a can promote the charging of the battery 2 charging facilitate voltage V ₂ (14.5 V). The battery 2 is actively charged and becomes fully charged. Then, the full charge judgment signal from the full charge determining unit 9 p2 is input, receives the full charge judgment signal p2, the terminal open circuit voltage corresponding to the second charging rate P ₂ that has been input from the charge rate setting unit 7 output voltage V _a of the generator 3 is set to the matching voltage. As a result, the battery 2 is forcibly discharged from the fully charged state until the second charging rate P ₂ is reached.

The charge / discharge amount calculation unit 10 receives an output signal from the current sensor 21 connected to the battery 2, integrates the charge / discharge current C of the battery 2 detected by the current sensor 21, and charges / discharges the battery 2. The quantity q is calculated. Therefore, if full charge capacity Q _f of the battery 2 is known, by the charge and discharge amount calculating unit 10, it is possible to detect the capacity Q of the battery 2 at all times. In addition, the charge / discharge amount calculation unit 10 receives the trigger signal t from the discharge control unit 52 and charges / discharges current C of the battery 2 during discharge from the first charge rate P ₁ to the second charge rate P _2. Is added to calculate the control discharge amount q _c .

The full charge capacity calculation unit 11 calculates the full charge capacity from the control discharge amount q _c of the battery 2 calculated by the control discharge amount calculation unit 10 a and the second charge rate P ₂ output from the charge rate setting unit 7. to calculate the Q _f. Specifically, since the capacity of the battery 2 corresponding to ΔP (= 100−P ₂ ) [%], which is the difference between the fully charged state and the second charging rate P ₂ , becomes the control discharge amount q _c , q _c / By calculating (ΔP / 100), the full charge capacity Q _{f of the} battery 2 is calculated. The full charge capacity Q _f is output to the full charge capacity storage unit 12.

The full charge capacity storage section 12 has stored the full charge capacity Q _f of the battery 2. Specifically, before the battery replacement, the full charge capacity Q _f of the genuine battery 2a is stored in advance. After the battery replacement, the full charge capacity Q of the battery 2b after replacement detected by the full charge capacity calculation unit 11 is stored. Remember _f . In this way, the battery 2 is going to update the full charge capacity Q _f of the battery 2b after the exchange each time it is exchanged. The full charge capacity storage unit 12 is not limited to the one that updates the full charge capacity Q _f of the battery 2b after replacement, and all the batteries 2b replaced from the genuine batteries 2a installed at the time of shipment. ,... May be stored. However, when detecting the capacity Q of the battery, the full charge capacity Q _f of the latest battery 2b among the stored full charge capacity Q _f is used.

  The engine start detection unit 13 detects the engine rotation speed Ne, and determines that the engine start has been completed when the engine rotation speed Ne is 500 rpm or higher, and sends an engine start detection signal p3 to the output voltage control unit 5. Output.

  The deceleration state detection unit 14 detects the vehicle speed S of the vehicle and the throttle opening θ of the engine intake device, and determines the deceleration state of the vehicle. When the throttle opening θ is fully closed and the vehicle speed S is greater than or equal to a predetermined speed, the deceleration detection signal p4 is output to the output voltage control unit 5 assuming that the vehicle is in a deceleration state.

Decelerating the output voltage control unit 51 in the output voltage control unit 5, in response to the deceleration state of the capacitor Q and the vehicle battery 2 performs output voltage control during deceleration to change the output voltage V _a of the generator 3.

The deceleration output voltage control unit 51 first detects the capacity Q of the battery 2. Specifically, the battery capacity Q is detected by adding or subtracting the charge / discharge amount q calculated by the charge / discharge amount calculator 10 to the full charge capacity Q _f of the battery 2.

The capacity Q of the battery 2 is greater than the first capacitor Q ₁ sets the output voltage V _a of the generator 3 to the first voltage V _1. Here, the first capacity Q ₁ is a threshold value of the battery capacity that can be determined that the state of charge of the battery 2 is good and that it is not necessary to charge the battery positively. The rate is set at 90%. The first voltage V ₁ is a voltage that suppresses charging of the battery 2, and is set to 12 V in the first embodiment. On the other hand, the capacity Q of the battery 2 in the case of the second capacitor Q ₂ below, sets the output voltage V _a of the generator 3 to a second voltage V _2. Here, the second capacity Q ₂ is a threshold value of the battery capacity that the battery 2 needs to be charged, and in the first embodiment, the charging rate is 80%. In addition, the second voltage V ₂ is a voltage that can promote the charging of the battery 2, and is set to 14.5 V in the first embodiment.

When the capacity Q of the battery 2 is greater than the second capacity Q ₂ (charging rate 80%) and less than or equal to the first capacity Q ₁ (charging rate 90%), power generation is performed according to the deceleration state of the vehicle. The output voltage V _{a of the} machine 3 is set. Specifically, when the decelerating state in the deceleration state detector 14 is detected deceleration detection signal p4 is output, the output voltage V _a of the generator 3 is set to a second voltage V ₂ which can promote the charging Is done. Meanwhile, instead of the deceleration state, when the deceleration detection signal p4 is not output, the output voltage V _a of the generator 3 is set to the first voltages V ₁ suppresses the charging.

That is, in the decelerating output voltage control, when capacity Q of the battery 2 is greater than the first capacity Q _1, i.e., when the charge state good, the inhibit charging the output voltage V _a of the generator 3 Fuel consumption is improved by setting to 1 voltage V ₁ . Further, when the capacity Q of the battery 2 of the second capacitor Q ₂ or less, i.e., when the charge is insufficient, and the output voltage V _a of the generator 3 is set to a second voltage V ₂ which can promote the charge The battery 2 is positively charged. Furthermore, the capacity Q of the battery 2 is not more first capacitor Q ₁ or less and when the second greater than the capacity Q _2, when the vehicle is in the non-reduction state, the first voltage the output voltage V _a of the generator 3 while improving the fuel efficiency by setting V _1, when the vehicle is in the deceleration state, the output voltage V _a of the generator 3 is set to a second voltage V _2, actively controlled to charge the battery 2 I do. In this way, based on the decelerating state of the capacitor and a battery of the vehicle 2, by controlling the output voltage V _a of the generator 3, it is possible to realize the recovery of improved and efficient energy in fuel consumption.

Thus, the discharging control by the discharging control unit 52 can detect the full charge capacity Q _f of the battery 2b by calculating the control discharge quantity q _c in the control discharge amount calculating unit 10a. The second charging rate P ₂ is the larger the difference between the full charge state, the full charge capacity Q _f of determined battery 2b will be accurate. However, if the difference between the fully charged state and the second charging rate P ₂ is too large, the time required for the discharge control becomes long, which is not practical. Therefore, it is preferable to determine the second charging rate P ₂ in consideration of the accuracy of the required full charge capacity Q _f and the detection time.

Further, by the deceleration output voltage control unit 51, depending on the deceleration state of the vehicle, by changing the output voltage V _a of the generator 3, which enables efficient recovery of improving the energy of fuel consumption.

  When the battery 2 is replaced, that is, after the replacement detection unit 6 detects the replacement of the battery 2, the discharge control is performed until the full charge capacity of the replaced battery 2b is detected. This deceleration output voltage control is prohibited. As a result, the battery 2b after replacement with an unknown full charge capacity is not overcharged or overdischarged, and a reduction in the life of the battery 2b is prevented.

  Next, an example of the battery capacity detection procedure will be specifically described based on the flowchart of FIG.

First, in step SA1, it is determined whether or not battery replacement is detected by the replacement detection unit 6. If battery replacement has been detected by the replacement detection unit 6, that is, if it has been detected that the battery voltage _Vb has become zero, it is determined Yes and the process proceeds to step SA2. On the other hand, if the battery replacement is not detected by the replacement detection unit 6, the determination is No and the process proceeds to Step SA7.

  In step SA2, the engine speed Ne is detected. In step SA3, it is determined whether or not the engine has been started. Specifically, if the engine rotation speed Ne is 500 rpm or more, it is determined that the engine start is completed (Yes), and if it is less than 500 rpm, it is determined that the engine start is not completed (No). If Yes, the process proceeds to Step SA4. If No, the process returns to Step SA2. Steps SA2 and SA3 are performed by the engine start detection unit 13. Note that the engine rotation speed used as the engine start determination value is not limited to 500 rpm, and can be set to any value that can confirm completion of engine start.

At step SA4, the output voltage V _a of the generator 3 is set to the voltage V ₂ to facilitate the charging of the battery 2b after the replacement (14.5 V). The set voltage V ₂ is not limited to 14.5V, and can be set to any value as long as it is a value that promotes charging of the battery 2b. Thereafter, in step SA5, the charge / discharge current C of the battery 2b is detected. Subsequently, in step SA6, the charge and discharge current C of the battery 2b is to or less than the predetermined value C _r is determined. As described above, the charge / discharge current C converges to a constant value in the fully charged state. That is, in step SA6, by setting the predetermined value C _r to the charge and discharge current in RyakuMitsuru charging state, the battery 2b is judged whether or not the fully charged state substantially. If the charging / discharging current C of the battery 2b is equal to or less than the predetermined value C _r , the determination is Yes and the process proceeds to step SA12. On the other hand, if the charge / discharge current C is greater than the predetermined value C _r , the determination is No and the process returns to step SA4.

  That is, the battery 2b is charged to a substantially fully charged state by executing the procedure from step SA2 to step SA6, which is determined as Yes.

  After the battery 2b is substantially fully charged, the discharge control is performed by executing the procedure from step SA12 to step SA14.

First, in step SA12, set to a voltage that matches the terminal open circuit voltage corresponding to the output voltage V _a of the generator 3 to the second charging rate P _2. The terminal open circuit voltage corresponding to the second charging rate P ₂ is obtained from the open circuit voltage characteristic stored in the open circuit voltage characteristic storage unit 8. By doing so, until the battery voltage V _b is balanced and the output voltage V _a of the generator 3, the battery 2 is discharged. Note that, in an equilibrium state where the battery voltage V _b and the output voltage V _a of the generator 3 are balanced, the terminal voltage of the battery voltage V _b corresponding to the second charging rate P ₂ due to the influence of the electric load 1a of the vehicle and the like. It may be out of place. In such a case, by the feedback control or the like, sets the output voltage V _a of the generator 3 as the battery voltage V _b is coincident with the terminal open circuit voltage corresponding to the second charging rate P _2.

Subsequently, in step SA13, it starts integration of the discharge current C of the second after setting the output voltage V _a of the generator 3 into a voltage matching the charging rate terminal open circuit voltage corresponding to P ₂ battery 2b.

In step SA14, it determines whether the charging rate of the battery 2b matches the second charging rate P _2. In this determination, it is determined whether or not the battery voltage V _b matches the terminal open voltage corresponding to the second charging rate P ₂ obtained from the open voltage characteristics of the open voltage characteristic storage unit 8.

Thus, the control discharge quantity q _c of the battery 2b while the battery 2b is discharged from a substantially fully charged state to a second charging rate P ₂ is detected. The control discharge amount q _c of the battery 2b is calculated by the control discharge amount calculation unit 10a.

Then, in step SA15, the control discharge quantity q _c and full charge capacity Q _f of the second after the replacement from the charging rate P ₂ battery 2b is calculated. Specifically, since the capacity corresponding to the difference ΔP (= 100−P ₂ ) [%] between the fully charged state, that is, the charging rate 100% and the second charging rate P ₂ is the control discharge amount q _c ,
Q _f = q _c / ((100-P ₂ ) / 100) (1)
Thus, the full charge capacity Q _f of the battery 2b after replacement is calculated.

Thus, the battery capacity detection is completed. When the full charge capacity Q _f of the battery 2b after replacement is detected, subsequently, deceleration output voltage control is performed. That is, when the battery 2 is replaced, since the always detects the full charge capacity Q _f of the battery 2b after the replacement, when the output voltage control deceleration is performed.

On the other hand, if it is determined No in step SA1, the process proceeds to step SA7. This step SA7 is the same procedure as step SA2, and the procedure from step SA8 to step SA11 following step SA7 is the same as the procedure from step SA3 to step SA6. That is, when the battery is not exchanged, the battery 2 is charged to a substantially fully charged state according to the procedure from step SA7 to step SA11. And if it determines with Yes in step SA11, it will progress to the output voltage control at the time of deceleration. That is, if the replacement of the battery 2 has not been made, without detecting the full charge capacity Q _f of the battery 2 by the discharge control, the full charge capacity Q _f of the battery 2, which is stored in the full charge capacity storage unit 12 By using this, the output voltage control during deceleration is performed. The full charge capacity storage unit 12, if the battery 2 is not replaced even once, is stored full charge capacity Q _f genuine battery 2a is, if the battery 2 is already replaced, after replacement the obtained full charge capacity Q _f is stored for the battery 2b.

  Next, an example of the battery deceleration output voltage control procedure will be specifically described with reference to the flowchart of FIG.

  First, in step SB1, the vehicle speed S, the throttle opening θ, and the charge / discharge current C are detected.

Subsequently, in step SB2, it is determined whether or not the battery capacity Q is equal to or less than the first capacity Q ₁ (charging rate 90%). If the battery capacity Q is first capacitor Q ₁ or less, the process proceeds is determined Yes to Step SB3, if the battery capacity Q is greater than the first capacity Q _1, proceeds No is determined to step SB6.

In step SB3, it is determined whether or not the battery capacity is equal to or less than the second capacity Q ₂ (charging rate 80%). Then, if the battery capacity Q is a second capacitor Q ₂ or less, while it is determined as Yes advances to step SB4, the process proceeds larger battery capacity Q than the second capacitor Q _2, it is determined as No to step SB5 .

In step SB4, set the generator 3 of the output voltage V _a possible promote charging of the second voltage V ₂ (= 14.5V). Then, it returns and returns to step SB1.

On the other hand, step SB2 in the case where the battery capacity Q is determined to be greater than the first capacitor Q ₁ proceeds to step SB6, in step SB6, the generator 3 of the output voltage V _a first voltage suppress charging V ₁ Set to (= 12V). Then, it returns and returns to step SB1.

Further, when it is judged No in step SB3, that is, the vehicle speed battery capacity Q is the case even with greater and than the second capacitor Q ₂ is first capacitor Q ₁ or less, in step SB5, detected in step SB1 It is determined whether or not the vehicle is decelerating based on S and the throttle opening θ. If it is determined that the vehicle is decelerating, the process proceeds to step SB4. If it is determined that the vehicle is not decelerating, the process proceeds to step SB6.

In this way, taking into account the deceleration state of the battery capacity Q and the vehicle, the deceleration output voltage control for setting the output voltage V _a of the generator 3 is carried out.

Therefore, according to the first embodiment, even after the battery is replaced, the full charge capacity Q _f of the battery 2b after the replacement can be easily obtained by performing the discharge control of the battery 2b based on the open-circuit voltage characteristics of the battery 2. And it can detect with sufficient precision. As a result, even if the battery 2b genuine battery 2a different full charge capacity Q _f is mounted by the battery exchange, since the full charge capacity Q _f of the battery 2b is detected accurately, the overcharge or over-discharge of the battery 2b It is possible to prevent the life of the battery 2b from being reduced.

By setting the first charging rate P ₁ to the fully charged state, the discharge control is performed in the vicinity of the fully charged state, and after the discharge control to the substantially fully charged state, which is a preferable charged state of the battery 2 during normal use. It can be charged early. The detection of the full charge capacity Q _f of the battery 2b after the replacement is preferably carried out after the engine is started first, but before the engine start SOC is slightly decreased, the first charging rate P ₁ By setting it to a substantially fully charged state, the battery 2b can be charged to a substantially fully charged state first.

Further, according to the capacity of the battery 2 and the decelerating state of the vehicle, and the output voltage controls the output voltage V _a of the generator 3, the recovery and fuel economy of prevention and efficient energy overcharge and over-discharge of the battery 2 Can be improved.

<< Embodiment 2 of the Invention >>
Next, Embodiment 2 of the present invention will be described. In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and further description thereof is omitted.

A flowchart of the battery capacity detection method according to the second embodiment is shown in FIG. The second embodiment is different from the first embodiment in that the first charging rate P ₁ is not fixed to the fully charged state, and can be set by the charging rate setting unit 7 in the same manner as the second charging rate P _2. It is that. However, the first charging rate P ₁ is larger than the second charging rate P ₂ .

  First, steps SC1 to SC3 are the same as steps SA1 to SA3 of the first embodiment.

Then, in step SC4, set to a voltage that matches the terminal open circuit voltage corresponding to the output voltage V _a of the generator 3 to the first charging rate P _1. The terminal open circuit voltage corresponding to the first charging rate P ₁ is obtained from the open circuit voltage characteristic stored in the open circuit voltage characteristic storage unit 8. By doing so, the battery voltage V _b and the output voltage V _a of the generator 3 are balanced, and the battery voltage V _b matches the terminal open voltage corresponding to the first charging rate P ₁ , that is, the battery 2 is in the first charge. the rate P _1.

Then, in step SC5, it determines whether the charging rate of the battery 2b matches the first charging rate P _1. In this determination, it is determined whether or not the battery voltage V _b matches the terminal open voltage corresponding to the first charging rate P ₁ obtained from the open voltage characteristics of the open voltage characteristic storage unit 8.

Thus, step SC4 and SC5 to the battery voltage V _b is coincident with the terminal open circuit voltage corresponding to the first charging rate P ₁ is repeated, the battery 2b is set to the first charging rate P _1.

Subsequently, in step SC6, set to a voltage that matches the terminal open circuit voltage corresponding to the output voltage V _a of the generator 3 to the second charging rate P _2. The terminal open circuit voltage corresponding to the second charging rate P ₂ is obtained from the open circuit voltage characteristic stored in the open circuit voltage characteristic storage unit 8.

In step SC7, starts integration of the discharge current C of the second after setting the output voltage V _a of the generator 3 into a voltage matching the charging rate terminal open circuit voltage corresponding to P ₂ battery 2b.

In step SC8, it determines whether the charging rate of the battery 2b matches the second charging rate P _2. In this determination, it is determined whether or not the battery voltage V _b matches the terminal open voltage corresponding to the second charging rate P ₂ obtained from the open voltage characteristics of the open voltage characteristic storage unit 8.

Thus, the control discharge quantity q _c of the battery 2b while the battery 2b is discharged from the first charging rate P ₁ to a second charging rate P ₂ is detected. The control discharge amount q _c of the battery 2b is integrated by the control discharge amount calculation unit 10a.

In step SC9, the full charge capacity Q _f of the battery 2b after replacement is calculated from the control discharge amount q _c , the first charge rate P _1, and the second charge rate P ₂ . Specifically, since the capacity corresponding to the difference ΔP ₁₂ (= P ₁ −P ₂ ) [%] between the first charging rate P ₁ and the second charging rate P ₂ is the control discharge amount q _c ,
Q _f = q _c / ((P ₁ -P ₂ ) / 100) (2)
Thus, the full charge capacity Q _f of the battery 2b after replacement is calculated.

Steps SC10 to SC14 are the same as steps SA7 to SA11 of the first embodiment. In the equilibrium state of the battery voltage V _b and the output voltage V _a of the generator 3 are balanced, the battery voltage V _b is the first charging rate P ₁ and the second charging rate P due to the influence of the electric load 1a of the vehicle _It may deviate from the terminal open voltage corresponding to ₂ . In such a case, the output voltage V _a of the generator 3 is set by feedback control or the like so that the battery voltage V _b matches the terminal open voltage corresponding to the first charging rate P ₁ or the second charging rate P _2. .

  Thus, the battery capacity detection is completed. Thereafter, the deceleration output voltage control is performed as in the first embodiment.

Thus, even if the first charging rate P ₁ is not in the fully charged state, by setting an arbitrary charging rate larger than the second charging rate P ₂ , the full charging capacity Q _f of the battery 2b after replacement is set. Can be detected. The greater the difference between the first charging rate P ₁ and the second charging rate P ₂ , the more accurate the required full charge capacity Q _f of the battery 2b. However, if the difference between the first charging rate P ₁ and the second charging rate P ₂ is too large, the time required for the discharge control becomes long and is not practical. Therefore, it is preferable that the first charging rate P ₁ and the second charging rate P ₂ are determined in consideration of the accuracy of the required full charge capacity Q _f and the detection time.

It is a block diagram showing a schematic structure of a power generator concerning an embodiment of the present invention. It is a figure which shows the open circuit voltage characteristic of a battery. It is a figure which shows the relationship between the charging current of a battery, and a charging rate. It is a flowchart figure which shows the procedure of the capacity | capacitance detection of the battery which concerns on Embodiment 1 of this invention. It is a flowchart figure which shows the procedure of the output voltage control at the time of the deceleration of a generator. It is a flowchart figure which shows the procedure of the capacity | capacitance detection of the battery which concerns on Embodiment 2 of this invention.

Explanation of symbols

1a Electric load 2 Battery 21 Current sensor (current detection means)
3 Generator 4 Controller 5 Output voltage controller (voltage control means)
6 Exchange detection unit 8 Open-circuit voltage characteristic storage unit 9 Full charge determination unit (full charge state determination means)
10 Charge / Discharge Amount Calculation Unit 11 Full Charge Capacity Calculation Unit (Capacity Calculation Means)
12 Fully charged capacity storage (capacity storage means)
14 Deceleration state detector

Claims (3)

Current detection means for detecting a charge / discharge current of a battery mounted on the vehicle;
Charge / discharge amount calculation means for calculating the charge / discharge amount of the battery by integrating the charge / discharge current detected by the current detection means;
Capacity storage means for storing the full charge capacity of the battery, and a battery capacity detection device comprising:
Voltage control means for controlling the output voltage of a generator driven by an engine to supply power to the battery and the electric load for the vehicle;
Replacement detection means for detecting that the battery has been replaced;
An open-circuit voltage characteristic storage means for storing an open-circuit voltage characteristic that is a relationship between the terminal open-circuit voltage and the charging rate of the battery;
Capacity calculation means for calculating a full charge capacity which is a capacity at the time of substantially full charge of the battery, further comprising:
When the battery detection is detected by the replacement detection means, the voltage control means corresponds to the output voltage of the generator corresponding to a predetermined first charging rate based on the open voltage characteristics stored in the open voltage storage means. After the battery is set to a voltage that matches the terminal open voltage of the battery, the battery discharge control is performed, which is set to a voltage that matches the battery terminal open voltage corresponding to the second charge rate lower than the first charge rate. ,
The charge / discharge amount calculation means calculates a control discharge amount discharged from the battery by integrating the discharge current detected by the current detection means while the voltage control means is executing discharge control. ,
The capacity calculation means calculates the full charge capacity of the battery after replacement from the difference between the first charge rate and the second charge rate and the control discharge amount,
The battery capacity detection device stores the full charge capacity of the battery after replacement calculated by the capacity calculation means. Current detection means for detecting a charge / discharge current of a battery mounted on the vehicle;
Charge / discharge amount calculation means for calculating the charge / discharge amount of the battery by integrating the charge / discharge current detected by the current detection means;
Capacity storage means for storing the full charge capacity of the battery, and a battery capacity detection device comprising:
Voltage control means for controlling the output voltage of a generator driven by an engine to supply power to the battery and the electric load for the vehicle;
Replacement detection means for detecting that the battery has been replaced;
An open-circuit voltage characteristic storage means for storing an open-circuit voltage characteristic that is a relationship between the terminal open-circuit voltage and the charging rate of the battery;
Capacity calculation means for calculating a full charge capacity that is a capacity at the time of substantially full charge of the battery;
A full charge state determination unit that determines a full charge state of the battery based on the charge / discharge current detected by the current detection unit;
When the battery detection is detected by the replacement detection means, the voltage control means determines that the battery is in a fully charged state by the full charge state determination means, and then opens the open voltage stored in the open voltage storage means. Based on the voltage characteristics, the output voltage of the generator is set to a voltage that matches the terminal open voltage of the battery corresponding to a predetermined charging rate lower than the fully charged state, and the battery discharge control is performed.
The charge / discharge amount calculation means calculates a control discharge amount discharged from the battery by integrating the discharge current detected by the current detection means while the voltage control means is executing discharge control. ,
The capacity calculation means calculates the full charge capacity of the battery after replacement from the difference between the full charge and the predetermined charge rate and the control discharge amount,
The battery capacity detection device stores the full charge capacity of the battery after replacement calculated by the capacity calculation means. The battery capacity detection device according to claim 1 or 2,
A deceleration state detecting means for detecting deceleration of the vehicle,
The voltage control means is
Based on the detection result of the deceleration state detection means and the full charge capacity of the battery stored in the capacity storage means, when the vehicle is not in the deceleration state, the output voltage of the generator is charged to the battery. While the vehicle is in a decelerating state, the output voltage is controlled to a second voltage that promotes charging of the battery.
When the replacement detection means detects the replacement of the battery, the output voltage control during deceleration is prohibited after the detection until the full charge capacity of the replaced battery is detected by the capacity detection means. A power generator characterized by the above.

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