JPH06296302A - Controller for engine-driven generator for electirc vehicle - Google Patents

Abstract

PURPOSE:To prevent occurrence of sulfation of a main battery to be charged by an engine-driven generator. CONSTITUTION:A timer is provided in a vehicle ECU (electronic control unit). When a value of the timer becomes a predetermined value (203), easy occurrence of sulfation is judged, and a process for full charging is conducted (205-207). Thus, when the sulfation tends to occur, the battery is fully charged to prevent occurrence of the sulfation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is mounted on an electric vehicle that drives a motor by the electric power of a main battery and the power output of an engine-driven generator to drive the vehicle, and the state of charge of the main battery (SO
C: State Of Charge) for a control device for an engine-driven generator for an electric vehicle, which operates or stops the engine-driven generator.

[0002]

2. Description of the Related Art In recent years, electric vehicles have been attracting attention from the viewpoint of pollution prevention. An electric vehicle is equipped with a chargeable / dischargeable battery such as a lead battery as an energy source (main battery) for driving a traveling motor. However, even if this type of battery has a considerably large volume and a large weight, the traveling distance is not so large due to its electric capacity. Therefore, in order to extend the mileage per charge, an electric vehicle (hybrid vehicle) having a configuration equipped with an engine-driven generator has been developed. The engine-driven generator is a device that is composed of an engine and a generator and that drives the generator to rotate by the mechanical output of the engine. For example, in a series hybrid vehicle, electric power is driven not only by the main battery but also by the engine-driven generator for the traveling motor, and the main battery can be charged by the power output of the engine-driven generator.
By adopting such a configuration, the mileage per charge can be extended and the volume of the main battery
The weight can be reduced. Furthermore, by appropriately controlling the power generated by the engine-driven generator, the charging frequency of the main battery using an external power source can be suppressed. In addition, when the engine-driven generator is operated, it can be operated in a region where emission and fuel consumption are good, and the object (pollution prevention) contradictory that accompanies mounting the engine hardly occurs.

Further, the frequency of operation of the engine-driven generator can be suppressed. That is, in the operation of the engine-driven generator in this type of vehicle, exhaust gas is generated to some extent and noise is generated even in the low emission region. Therefore, for example, as disclosed in JP-A-55-157901. Then, when the SOC of the main battery decreases. In this publication, when the SOC of the main battery (directly, the electrolyte specific gravity of the main battery, which is an amount corresponding to the SOC) is reduced, the engine that constitutes the engine-driven generator is operated to start power generation, The engine is stopped when the SOC of the main battery is restored. By such control, the engine operating frequency can be minimized and low pollution can be maintained.

[0004]

By applying the technique (power generation / power generation stop control based on the SOC value) described in the above publication, the life of the main battery is extended and the pollution originally intended for the electric vehicle is reduced. Can contribute to prevention.

First, in the configuration in which the engine-driven generator is driven when the SOC of the main battery is lowered, when the SOC is lowered when the vehicle is running, the power required for driving the motor is generated by the engine-driven generator. Part of it, or in the prominent case, it will be covered by the discharge power of the main battery. In such a state, charging of the main battery does not proceed easily. This means that the operating time of the engine-driven generator becomes very long, and the advantage of the electric vehicle is impaired. On the other hand, charging the main battery becomes less efficient as it approaches full charge. In addition, it is necessary to reduce the charging current near full charge, and therefore reducing the engine output makes it difficult to take measures against exhaust gas. Therefore, the main battery is charged before the full charge by the power generation control of the engine-driven generator, for example, S
The control is terminated when the OC is recovered to about 80%, and the engine-driven generator is stopped. By performing such control, the operating time of the engine-driven generator can be suppressed appropriately.

When a lead battery is used as the main battery, the life of the main battery can be properly secured by controlling the SOC of the lead battery in the range of, for example, 60 to 80%. The above-mentioned technique can be applied to the purpose of realizing such SOC management.

However, when a lead battery is used as the main battery, if the battery is continuously used such that charging / discharging that does not result in full charge is repeated, sulfation occurs at the negative electrode of the main battery. Sulfation is a phenomenon in which crystals of lead sulfate (PbSO ₄ ) generated at the time of discharge become coarse and cannot return to the original state of lead (Pb) and lead oxide (PbO ₂ ) even after charging. That is, in a lead battery, the lead oxide of the anode and the lead of the cathode become lead sulfate during discharging, and the reaction of returning to the original state by charging is repeated. The lead sulfate generated by the discharge returns to lead or lead oxide if it is immediately charged, but if it is in the state of lead sulfate for a long time, lead sulfate grows as a crystal and becomes passivated. When such a phenomenon, that is, sulfation occurs, that portion does not operate as a battery. Therefore, the electrode area is reduced, the battery capacity is reduced, the main battery is rapidly deteriorated, and the life is shortened.

The present invention has been made to solve the above problems, and detects the possibility of sulfation in the main battery and fully charges the main battery at a predetermined timing to prevent the sulfation from occurring. An object is to obtain a control device for an engine-driven generator for an electric vehicle that can be prevented.

[0009]

In order to achieve such an object, the present invention provides a full-charge necessary state means for detecting that the possibility of sulfation in a main battery has reached a predetermined level or more, and By operating the engine-driven generator when the possibility exceeds a certain level,
Full charge control means for charging the main battery until it is fully charged.

The present invention is characterized by comprising full charge control avoiding means for avoiding control for fully charging the main battery when the SOC of the main battery is lower than a predetermined level.

The present invention is characterized in that the full charge control means relaxes the limitation of the voltage applied to the main battery when the main battery is charged.

According to the present invention, the full charge control means controls the voltage (threshold voltage) applied to the main battery to the above-mentioned limit.
Is reached and the charging current of the main battery becomes equal to or less than a predetermined value, it is considered that the main battery has reached a fully charged state, and the relaxation of the restriction is released.

The present invention is characterized in that the full charge control means corrects the threshold voltage in accordance with the temperature of the main battery.

[0014]

In the present invention, when the possibility of sulfation in the main battery exceeds a predetermined level, the engine-driven generator operates and the charge control of the main battery is executed until the battery is fully charged. Therefore, it is possible to prevent the occurrence of sulfation even in a vehicle in which the main battery is not fully charged during traveling. This can reduce damage to the main battery and prolong the life of the main battery. Further, since the detection related to the above possibility can be executed based on various quantities indicating the frequency of charge control of the main battery, structural change of the main battery is unnecessary. Furthermore, full charge control is
It can be executed in any state, such as when the vehicle has finished traveling, when it is temporarily stopped, or when it is traveling.

Further, in the present invention, the SOC of the main battery is
Is lower than a predetermined level, full charge control is avoided. Therefore, since the full charge control of the main battery is performed in a relatively good state where the SOC is 80% or more, the main battery is fully charged in a short time, especially when the vehicle is parked or stopped. When performing control, the engine operating time after parking / stopping is shortened.

In the present invention, the threshold voltage is changed to a higher value during full charge control, so the time required for full charge (equal charge time) is shortened.

Further, in the present invention, when the voltage applied to the main battery reaches the threshold voltage and the charging current of the main battery becomes less than or equal to the predetermined value, it is considered that the main battery has reached the fully charged state. That is, as the charging progresses, the voltage of the main battery rises, and in the state where constant voltage charging at the threshold voltage is reached, full charge is detected with a current decrease caused by the progress of charging under constant voltage. . Therefore, the relaxation of the voltage limitation (control for returning the threshold voltage to the original value) can be executed by monitoring the voltage and current of the main battery.

In the present invention, the threshold voltage is corrected according to the temperature of the main battery. Therefore, the damage of the main battery, which is caused by the increase of the threshold voltage and is dependent on the temperature, is preferably suppressed.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings.

Apparatus Configuration FIG. 1 shows the configuration of an electric vehicle suitable for carrying out each embodiment of the present invention described later.

The electric vehicle of this figure is equipped with an engine-driven generator composed of an engine 1 and a generator 2. The engine 1 is, for example, a gasoline engine, and drives the generator 2 by its mechanical output. The generator 2 generates power when driven by the engine 1 while being supplied with the field current _If . In the case of this figure, the generator 2 is an AC generator, and the power generation output thereof is rectified by the rectifier 3 in the subsequent stage. Of course, a DC generator may be used as the generator.

The electric vehicle shown in this figure is further equipped with a main battery 4 configured as a lead battery, an inverter 5 including a plurality of switching elements, and a motor 6 as a drive source for the vehicle. The output terminal of the rectifier 3, the terminal of the main battery 4, and the input terminal of the inverter 5 are in a direct connection state (when a contactor (not shown) is closed) as shown in the figure.
Therefore, the discharge power of the main battery 4 and the power generation output P _G of the generator 2 supplied via the rectifier 3 are input to the inverter 5 and converted into three-phase AC by the switching operation. The motor 6 is a three-phase AC induction motor and is driven by the output of the inverter 5. Of course, other types of motors may be used. The output torque of the motor 6 is transmitted to the tire 9 via a transmission (T / M) 7, a differential gear (differential gear) 8, etc., and an electric vehicle runs.

The main battery 4 can be charged not only by an external charging device using an external connection terminal (not shown) but also by the power output P _G of the generator 2 and the regenerative power of the motor 6.

In this figure, SOC is used as the sensor.
A meter 10, a current sensor 11, a voltage sensor 12, a temperature sensor 13 and a vehicle speed sensor 14 are provided. First,
The SOC meter 10 is a sensor that detects the SOC of the main battery 4, and for example, by integrating the charging / discharging current of the main battery 4, detecting the electrolytic solution specific gravity, and detecting the voltage-current characteristic during large current or high rate discharge, Detect SOC. The current sensor 11 and the voltage sensor 12 detect the charge / discharge current I _B or the voltage V _B of the main battery 4, respectively. Since the terminal of the main battery 4 is connected to the output terminal of the rectifier 3, the voltage V _B becomes equal to the output voltage of the rectifier 3. The temperature sensor 13 is a sensor attached to the main battery 4 and detecting the temperature T thereof. The vehicle speed sensor 14 is a sensor that detects the vehicle speed v, and is attached to, for example, the differential 8 as shown in this figure.

The various quantities detected by these sensors are input to a vehicle ECU (electronic control unit) 15. The vehicle shown in this figure is equipped with a vehicle ECU 15, an engine ECU 16, and a field controller 17 as means for controlling the drive system, and each of them operates by receiving power supply from an auxiliary battery 18. In addition to these, the auxiliary battery 18 is a battery for supplying power to an electric auxiliary device mounted on the vehicle, and outputs the outputs of the main battery 4 and the rectifier 3 to the DC-D.
It is charged by the voltage (auxiliary equipment voltage) obtained by the C converter 19.

The vehicle ECU 15 inputs a vehicle signal indicating the driver's accelerator operation, brake operation, etc., and controls the operation of the inverter 5 based on this signal, so that the output torque of the motor 6 is used for accelerator operation and brake operation. Control so that the torque is appropriate. At that time, vehicle E
The CU 15 monitors the amount of rotation of the motor 6 and the like.

The vehicle ECU 15 controls the output torque of the motor 6 as well as the engine ECU 16 and the field controller 1.
The commands for starting power generation, stopping power generation, changing the amount of power generation, etc. are given to 7 as appropriate. At that time, the vehicle ECU 15 uses the outputs of the various sensors described above to generate a command. Engine ECU
The field controller 16 and the field controller 17 control the engine 1 or the generator 2, respectively. For example, engine ECU1
Reference numeral 6 controls the throttle opening of the engine 1, the intake air amount, and the like. At that time, by efficiently operating the engine 1 with the throttle fully open, emissions and fuel consumption can be maintained at suitable values. Further, the field controller 17 controls the field current I _f of the generator 2. These, engine EC
By controlling U16 and the field controller 17, it is possible to control the power generation output P _G of the engine-driven generator, so that the charge / discharge of the main battery 4 can be controlled.

First Embodiment FIG. 2 shows a control flow of the vehicle ECU 15 in the first embodiment of the present invention, particularly a SOC management flow when the vehicle is running. As shown in this figure, the vehicle EC
U15 is the SOC of the main battery 4 from the SOC meter 10 first.
Enter (101), and SOC is a predetermined value (for example, 40%)
When it becomes below (102), a command is given to the engine ECU 16 and the field controller 17 to operate the engine-driven generator (103), and when the SOC becomes a predetermined high level (for example, 80%) (104) ) Engine ECU
A command is given to 16 and the field controller 17 to stop the engine-driven generator (105). That is, when the SOC of the main battery 4 is low and needs to be charged, the engine-driven power generator operates to generate power, and when the SOC is high, the power generation operation is stopped.
Further, in step 103, the voltage V _{B of the} main battery 4 is
Is controlled to be a voltage equal to or lower than a threshold voltage (which will be described later) while the power generation output P _G is controlled while feedback is added by the output of the voltage sensor 12.

FIG. 3 shows the vehicle ECU in this embodiment.
15 shows a control flow, particularly a flow at the end of traveling.

As shown in this figure, when the vehicle ends and the driver turns off the ignition switch (IG), the vehicle ECU 15 inputs the SOC of the main battery 4 from the SOC meter 10 (201). Vehicle ECU 15
Determines whether the SOC is greater than 80% (20
2) If it is larger, it is further determined whether or not the elapsed time t _cc since the last full charge is a specified time, for example, 100 H (hours) or more (203). That is, the vehicle E
The elapsed time t _cc is counted by the timer built in the CU 15. If it is determined in step 203 that the condition is satisfied, the process proceeds to step 204 and subsequent steps in order to execute full charge control in order to prevent sulfation. If it is determined that the condition is not satisfied, the routine proceeds to step 208, where a command is given to the engine ECU 16 and the field controller 17 to stop the engine-driven generator. The reason why the engine-driven generator is stopped is that it can be considered that the situation where sulfation is likely to occur has not yet been reached and the main battery 4 does not need to be fully charged. In step 202, the SOC is 8
If it is determined to be 0% or less, the process proceeds to step 208 and the engine-driven generator is stopped. This is because if the full charge control is performed when the SOC is low, the engine 1 must be operated for a long time after the IG is turned off.

The elapsed time t _cc from the last full charge is used to detect the situation where sulfation is likely to occur. That is, the sulfation is a reaction that occurs inside the main battery 4, and in order to prevent this, the main battery 4 must be fully charged before the sulfation occurs. On the other hand, if a long time has passed since the last full charge, it is considered that the lead sulfate crystals have coarsened to some extent during that time. From this point of view, in this embodiment, with the elapsed time t _cc from fully charged last, and detects the tendency of sulfation is towards the generator.

When the vehicle ECU 15 detects that the sulfation is about to occur,
Reset the built-in counter (elapsed time t _cc ) (20
4) Then, it is determined whether or not the SOC is 100%, that is, whether or not the battery is fully charged (205). Until the vehicle is fully charged, the vehicle ECU 15 controls the engine-driven generator, operates the generator 2, and charges the main battery 4 (2
06). The vehicle ECU 15 changes from the SOC meter 10 to the SO
Input C (207) and return to step 205. Therefore, the state in which the generator 2 is operated is continued until the SOC reaches 100%. When SOC reaches 100% (20
5) The process proceeds to step 208 and the power generation operation of the generator 2 is stopped.

Therefore, according to this embodiment, the possibility of sulfation in the main battery 4 is detected by using the elapsed time t _cc from the last full charge, and the main battery 4 is detected in response to the detection.
Since the battery is fully charged, sulfation in the main battery 4 can be preferably prevented, damage to the main battery 4 can be reduced, and the life of the main battery 4 can be extended. Furthermore, since this control is performed when the SOC of the main battery 4 is high, the time until the battery is fully charged can be shortened, and the engine 1 after the IG is turned off
It is possible to prevent the etc. from operating for a long time, and reduce the time of noise generation. However, this step 202 is not always essential and may be omitted. Further, according to the present embodiment, the SOC of the main battery 4 is controlled within the range of 40 to 80% during traveling, so that overcharging of the main battery 4 can be preferably prevented and the life thereof is secured. be able to.
Furthermore, the main battery 4 is used by using the generator 2 mounted on the vehicle.
Since it can be fully charged, there is also the advantage that no special charger is required.

Second Embodiment FIG. 4 shows a control flow of the vehicle ECU 15 in the second embodiment of the present invention, particularly a flow when the vehicle travel ends. This embodiment can be implemented with a vehicle configuration similar to that of the first embodiment. The control flow during traveling is the same as that in the first embodiment. This embodiment is different from the first embodiment in that the occurrence of sulfation is predicted by using not the elapsed time t _cc since the last full charge but the traveling distance L _cc after the last full charge. .

That is, during normal driving, the main battery 4
Because never but fully charged, when the running distance L _cc is a predetermined distance or more may be considered to be likely in sulfation occurred. Therefore, in this embodiment, steps 203A and 204A are executed instead of steps 203 and 204 in the first embodiment. In step 203A, the traveling distance L _cc is a specified value (for example, 500
The possibility of sulfation occurrence is determined based on whether or not the travel distance L _cc is exceeded, and in step 204A, the traveling distance L _cc is reset. In addition, this mileage L _cc
It is counted inside the vehicle ECU 15 using information such as the vehicle speed v.

With such control, the same operation and effect as those of the first embodiment can be obtained.

Third Embodiment FIG. 5 shows a control flow of the vehicle ECU 15 in the third embodiment of the present invention, particularly a flow at the end of traveling of the vehicle. This embodiment can be implemented with a vehicle configuration similar to that of the first and second embodiments. Further, the control flow during traveling is the same as in the first and second embodiments.
Is similar to. This example differs from Examples 1 and 2 in that the SOC of the main battery 4 is 5 after the last full charge.
The point is that the occurrence of sulfation is predicted by using the number N _cc of 0% or less.

That is, the occurrence of sulfation can be predicted depending on how many times the main battery 4 is repeatedly charged and discharged during traveling. So, in this example,
Steps 203B and 204B are executed instead of steps 203 and 204 in the first embodiment. Step two
In 03B, the possibility of occurrence of sulfation is judged depending on whether or not the number of times N _cc is a prescribed value (for example, 5 times), and in step 204B, the number of times N _cc is reset. The number of times _{Ncc is} also counted inside the vehicle ECU 15 based on the SOC monitoring result.

Even with such control, the same operation and effect as those of the first and second embodiments can be obtained.

Fourth Embodiment FIG. 6 shows a control flow of the vehicle ECU 15 in the fourth embodiment of the present invention, particularly a flow at the end of traveling of the vehicle. This embodiment can be implemented with a vehicle configuration similar to that of the first to third embodiments. The control flow during traveling is the same as that of the first to third embodiments. This example differs from Examples 1 to 3 in that the occurrence of sulfation is predicted using the integrated value Ah of the charging / discharging current of the main battery 4 after being fully charged last time.

That is, the occurrence of sulfation can be predicted depending on how much the main battery 4 is charged and discharged during traveling. Therefore, in this embodiment, steps 203C and 204C are executed instead of steps 203 and 204 in the first embodiment. Step 20
In 3C, the possibility of sulfation is determined depending on whether the integrated value Ah is equal to or greater than the specified value Ah0. In step 204C, the integrated value Ah is reset. The integrated value Ah is calculated in the vehicle ECU 15 based on the outputs of the current sensor 11 and the voltage sensor 13, or the integrated value obtained when the SOC is detected by the SOC meter 10 is diverted.

With this control, the first to third embodiments are also possible.
The same action and effect as can be obtained.

Embodiment 5 FIG. 7 shows a control flow of the vehicle ECU 15 in Embodiment 5 of the present invention, particularly a control flow when the vehicle is running. This embodiment can be implemented with a vehicle configuration similar to that of the first to fourth embodiments. In this embodiment, step 101A is executed instead of step 101 in the first to fourth embodiments. In this step, the vehicle ECU 15 sets the SO
SOC from the C meter 10 and vehicle speed v from the vehicle speed sensor 14
Are input respectively. The vehicle ECU 15 subsequently executes step 106. In this step,
The vehicle ECU 15 determines whether the vehicle speed v is 0, that is, whether the vehicle is stopped. As a result, when it is determined that the vehicle is not stopped, the vehicle ECU 15 determines
The SOC management from step 102 onward is executed in the same manner as in steps # 4 to # 4, and if it is determined to be stopped, the control shown in FIG.

Here, when the vehicle is traveling, the vehicle speed v becomes 0 when the vehicle is temporarily stopped by a signal or the like. In the case of the present embodiment, the full charge control of the main battery 4 is executed during such a temporary stop period.

In performing this control, the vehicle ECU
As shown in FIG. 8, first, 15 inputs the SOC of the main battery 4 from the SOC sensor 10 (301) and judges whether the SOC exceeds a specified value (for example, 80%) (30
2) If the determination is successful, then it is determined whether the elapsed time t _cc from the previous full charge is equal to or longer than a specified time (for example, 100H) (303). In this embodiment, when the determination in step 303 is established, the full charge control of step 304 and the subsequent steps is performed, and when the determination is not established, the process returns to the main routine. Accordingly, in this embodiment, with the elapsed time t _cc from likewise fully charged previous Example 1, and detects the occurrence probability of sulfation. At that time, unlike the first to fourth embodiments, the engine-driven generator is not stopped because the control in this figure is performed when the vehicle is temporarily stopped. Further, as in the first to fourth embodiments, the full charge control is not performed when the SOC is low.

When the possibility of sulfation is detected, the vehicle ECU 15 first resets the elapsed time t _cc (304) until the SOC reaches 100% (30
5) While inputting SCO (307), the control of the engine-driven generator is continued (306), and when the SOC reaches 100, the engine-driven generator is stopped (308) and the process returns to the main routine.

Therefore, according to this embodiment, the possibility of sulfation in the main battery 4 is detected by using the elapsed time t _cc since the last full charge, and the main battery 4 is detected in response to the detection.
Since the battery is fully charged, sulfation in the main battery 4 can be preferably prevented, damage to the main battery 4 can be reduced, and the life of the main battery 4 can be extended. Furthermore, since this control is performed when the SOC of the main battery 4 is high, the time until full charge can be shortened as much as possible, and charging is completed and noise is generated during a relatively short period such as when the vehicle is temporarily stopped. The time can be shortened. Step 302 is not always essential and may be omitted. Further, according to the present embodiment, the SOC of the main battery 4 is controlled within the range of 40 to 80% during traveling, so that overcharging of the main battery 4 can be preferably prevented and the life thereof is secured. be able to. Furthermore, since the main battery 4 can be fully charged using the generator 2 mounted on the vehicle, there is an advantage that no special charger is required.

Sixth Embodiment FIG. 9 shows a control flow of the vehicle ECU 15 in the sixth embodiment of the present invention, particularly a flow when the vehicle speed v = 0. This embodiment can be implemented with the same vehicle configuration as that of the first to fifth embodiments, and the control flow during traveling is the same as that of the fifth embodiment. The present embodiment is different from the fifth embodiment in that the occurrence of sulfation is predicted by using not the elapsed time t _cc since the last full charge but the travel distance L _cc after the last full charge. . Specifically, in this embodiment, steps 303A and 304A are executed instead of steps 303 and 304 in the fifth embodiment. Step 30
At 3A, the mileage L _cc is a specified value (eg 500km)
Whether or not sulfation has occurred is determined based on whether or not the above is true, and in step 304A, the traveling distance L _cc is reset. Even with such control, the same operation and effect as those of the fifth embodiment can be obtained.

Seventh Embodiment FIG. 10 shows a vehicle ECU 15 according to the seventh embodiment of the present invention.
The control flow of, particularly, the flow when the vehicle speed v = 0 is shown. This embodiment can be implemented with a vehicle configuration similar to that of the first to sixth embodiments, and the control flow during traveling is the same as that of the fifth and sixth embodiments. This example differs from examples 5 and 6 in that
Using the number N _cc of SOC of main battery 4 becomes 50% or less after fully charged last, in that it predicts the occurrence of sulfation. That is, steps 303B and 30 instead of steps 303 and 304 in the fifth embodiment.
Performing 4B. In step 303B, the number of times N _cc
The possibility of sulfation occurrence is determined based on whether or not is a specified value (for example, 5 times), and step 304
In B, the number of times _Ncc is reset. With such control, the same operation and effect as those of the fifth and sixth embodiments can be obtained.

Eighth Embodiment FIG. 11 shows a vehicle ECU 15 according to the eighth embodiment of the present invention.
The control flow of, particularly, the flow when the vehicle speed v = 0 is shown. This embodiment can be implemented with the same vehicle configuration as that of the first to seventh embodiments, and the control flow during traveling is the same as that of the fifth to seventh embodiments. This example differs from Examples 5 to 7 in that the occurrence of sulfation is predicted using the integrated value Ah of the charging / discharging current of the main battery 4 after being fully charged last time. That is, in this embodiment, step 303C replaces steps 303 and 304 in the fifth embodiment.
And 304C are running. In step 303C,
The possibility of sulfation occurrence is determined based on whether the integrated value Ah is equal to or greater than the specified value Ah0.
At 4C, the integrated value Ah is reset. Even by such control, the same operation and effect as those of the fifth to seventh embodiments can be obtained.

Embodiment 9 FIG. 12 shows a vehicle ECU 15 in Embodiment 9 of the present invention.
The control flow of the above, especially the flow when the vehicle is traveling is shown. This embodiment can be implemented with a vehicle configuration similar to that of the first to eighth embodiments.

In this embodiment, the vehicle ECU 15 first executes step 101 and then step 303. While the condition of step 303 is not satisfied, the control during normal running after step 102 is executed. When the condition of step 303 is satisfied and thus the possibility of sulfation is affirmed, the process proceeds to full charge control of step 309 and thereafter. In step 309, the vehicle EC
U15 current sensor 11, from the voltage sensor 12 and temperature sensor 13, charge-discharge current I _B of the main battery 4, and inputs the voltage V _B and the temperature T. The vehicle ECU 15 changes the threshold voltage V _th to a higher value while applying the correction based on the temperature T (310).

The threshold V _{th mentioned} here means the main battery 4
It is the upper limit voltage that is set when the charging control is performed. That is, when controlling the power generation output P _G of the generator 2, the charging voltage V _B of the main battery 4 is remarkably increased, and as a result, the main battery 4 is not overcharged. The power generation output P _G of the generator 2 is controlled while suppressing the charging voltage V _B to be less than the threshold voltage V _th . By performing control based on such threshold voltage V _th ,
It is possible to prevent the life from being shortened due to overcharge.

The threshold voltage V _th is set to a value of, for example, about 14 to 14.5 V / 6 cell module under normal conditions (step 103). In this embodiment, the judgment condition regarding the elapsed time t _cc (step 303)
This threshold voltage V _th is increased to a value of, for example, about 15 V / 6 cell module (310) each time the above condition holds, that is, periodically while the vehicle is traveling. By changing and setting the threshold voltage V _th in this manner and executing step 306, the power generation output P _G of the generator 2 and, consequently, the charge amount of the main battery 4 increases. Therefore, if charging is performed under this threshold voltage V _th (306) until a predetermined condition is satisfied (311 and 312), the main battery 4 can be fully charged quickly. When the above predetermined condition is satisfied (31
1, 312), the vehicle ECU 15 returns the threshold voltage V _th to the lower value (313), and further executes step 304. The routine of FIG. 12 is repeatedly executed when the vehicle is traveling.

The increase change of the threshold voltage V _th in this embodiment is executed according to FIG. 13 or 14. Figure 1
3 shows an example in which the threshold voltage V _th is changed in a single step, and FIG. 14 shows an example in which the threshold voltage V _th is changed in a plurality of steps. In particular, when the latter is adopted, the period in which the threshold voltage V _th is high can be made relatively short, and damage to the main battery 4 due to the increase control of the threshold voltage V _th can be suppressed to a small extent.

Further, in step 310, the threshold voltage V _th is further corrected based on the temperature T. That is, since the main battery 4 is easily damaged when the temperature T is high, in this embodiment, as shown in FIG. 15, the threshold voltage V _th decreases as the temperature T increases.
We are making corrections.

Further, in this embodiment, the determination as to whether the main battery 4 has reached full charge (uniform charge) is made based on the voltage V _B and the current I _B. That is, as the charging of the main battery 4 progresses, the voltage V _B thereof rises, and at a certain point,
The voltage that is limited in control, that is, the threshold voltage V
_{to th} . This state, i.e. in the state where the main battery 4 is constant-voltage charging in threshold voltage V _th, since current I _B as main battery 4 approaches the fully charged state decreases, the first voltage V _B at step 311 Threshold voltage V
By comparing _th and comparing the current I _B with a predetermined value I ₀ to detect the current I _B when the voltage V _B reaches the threshold voltage V _th , the fully charged state can be preferably detected.

Therefore, according to this embodiment, the possibility of sulfation in the main battery 4 is detected by using the elapsed time t _cc from the last full charge, and the main battery 4 is detected according to the detection.
Since the battery is fully charged, sulfation in the main battery 4 can be preferably prevented, damage to the main battery 4 can be reduced, and the life of the main battery 4 can be extended. Further, since this control is periodically performed while the vehicle is traveling, full charge can be performed at an appropriate frequency even in a normal use state in which the SOC does not reach a high level. Further, since the threshold voltage V _th is increased during the full charge control, it is possible to reduce the amount of charge and fully charge the battery quickly, thereby shortening the noise generation time. Further, according to the present embodiment, the SOC of the main battery 4 is controlled within the range of 40 to 80% during normal traveling, so that the overcharge of the main battery 4 can be preferably prevented and the life thereof is secured. can do. Furthermore, since the main battery 4 can be fully charged using the generator 2 mounted on the vehicle, there is an advantage that no special charger is required. In addition, as described above, the effect of the stepwise increase of the threshold voltage V _th and the temperature correction can be obtained. If maximum control power generation output P _G of the generator 2 when it is to increase the threshold voltage V _th, can shorten the time required for full charge, the damage of the main battery 4 due to increasing the threshold voltage V _th Can be reduced. The full charge control according to the flow of this embodiment can be executed even when the vehicle is stopped.

10th Embodiment FIG. 16 shows a vehicle ECU 1 according to a 10th embodiment of the present invention.
The control flow of No. 5 is shown, especially the flow when the vehicle is traveling at vehicle speed. This embodiment can be implemented with a vehicle configuration similar to that of the first to ninth embodiments. This embodiment is different from the ninth embodiment in that the occurrence of sulfation is predicted by using not the elapsed time t _cc since the last full charge but the traveling distance L _cc after the last full charge. . Specifically, in this embodiment, steps 303A and 304A are executed instead of steps 303 and 304 in the ninth embodiment. With such control, the same operation and effect as those of the ninth embodiment can be obtained.

Eleventh Embodiment FIG. 17 shows a vehicle ECU 1 according to the eleventh embodiment of the present invention.
The control flow of No. 5 is shown, especially the flow when the vehicle is traveling at vehicle speed. This embodiment can be implemented with a vehicle configuration similar to that of the first to tenth embodiments. Differs from this embodiment Examples 9 and 10, there is used a number of times N _cc of SOC of main battery 4 becomes 50% or less after fully charged last, in that predicts the occurrence of sulfation . That is, steps 303B and 304B are executed instead of steps 303 and 304 in the ninth embodiment. With such control,
The same operation and effect as those of the ninth and tenth embodiments can be obtained.

Embodiment 12 FIG. 18 shows a vehicle ECU 1 according to Embodiment 12 of the present invention.
The control flow of No. 5 is shown, especially the flow when the vehicle is traveling at vehicle speed. This embodiment can be implemented with a vehicle configuration similar to that of the first to eleventh embodiments. This example is different from Examples 9 to 10 in that
Integrated value A of charge / discharge current of main battery 4 after full charge last time
The point is that the occurrence of sulfation is predicted using h. That is, in this embodiment, steps 303C and 304C are executed instead of steps 303 and 304 in the ninth embodiment. With such control,
The same actions and effects as those of Examples 9 to 11 are obtained.

[0062] Other In Examples 5-12, it may be performed together any of the control examples 1-4. Further, any of Examples 5 to 8 and any of Examples 9 to 12 may be arbitrarily combined. Furthermore, although an example using a lead battery as the main battery 4 has been described, the present invention may be applicable to batteries other than lead batteries. That is, the present invention can be applied to any battery that can prevent or suppress the deterioration of the battery performance due to the crystal coarsening or the like inside the battery by repeating the charging that does not reach the full charge, and the deterioration can be prevented by the full charge. In that sense, the term sulfation referred to in the present application is not limited to passivation of lead sulfate in a lead battery, and has a concept including a similar phenomenon.

[0063]

As described above, according to the present invention,
When the possibility of sulfation in the main battery exceeds a certain level, the generator is activated to fully charge the main battery.Therefore, sulfation may occur even in a vehicle where the main battery does not become fully charged while driving. Can be prevented, damage to the main battery can be reduced, and the life of the main battery can be extended. Further, since the detection related to the above possibility can be executed based on various quantities indicating the frequency of charge control of the main battery, structural change of the main battery is unnecessary. Further, the full-charge control can be executed in any state such as when the vehicle has finished traveling, is temporarily stopped, or is traveling. In addition, it eliminates the need for external charging and does not require a vehicle-mounted or stationary charger.
The cost can be reduced.

Further, according to the present invention, since the full charge control is avoided when the SOC of the main battery is lower than a predetermined level, the main battery is fully charged in a short time when the full charge control is executed. Especially, when the full charge control is performed when the vehicle is parked or stopped, the engine operating time after the vehicle is parked is shortened. This leads to reduction of noise and the like.

According to the present invention, since the threshold voltage is changed to a higher value during full charge control, the time required for full charge (uniform charging time) can be shortened.

Further, according to the present invention, when the voltage applied to the main battery reaches the threshold voltage and the charging current of the main battery becomes equal to or less than the predetermined value, it is considered that the main battery has reached the fully charged state. Therefore, the relaxation of the voltage limitation (control for returning the threshold voltage to the original value) can be executed by monitoring the voltage and current of the main battery.

Further, according to the present invention, since the threshold voltage is corrected according to the temperature of the main battery, the damage of the main battery which is caused by the increase of the threshold voltage and is dependent on the temperature can be suitably suppressed. .

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a vehicle suitable for implementing each embodiment of the present invention.

FIG. 2 is a flowchart showing a traveling control flow of the vehicle ECU in the first to fourth embodiments.

FIG. 3 is a flowchart showing a post-travel control flow of the vehicle ECU in the first embodiment.

FIG. 4 is a flowchart showing a post-travel control flow of the vehicle ECU in the second embodiment.

FIG. 5 is a flowchart showing a post-travel control flow of the vehicle ECU in the third embodiment.

FIG. 6 is a flowchart showing a post-travel control flow of a vehicle ECU in the fourth embodiment.

FIG. 7 is a flow chart showing a traveling control flow of the vehicle ECU in the fifth to eighth embodiments.

FIG. 8 is a flowchart showing a control flow of a vehicle ECU at a vehicle temporary stop in the fifth embodiment.

FIG. 9 is a flowchart showing a control flow of a vehicle ECU when a vehicle is temporarily stopped in the sixth embodiment.

FIG. 10 is a flowchart showing a control flow of a vehicle ECU at a vehicle temporary stop in the seventh embodiment.

FIG. 11 is a flowchart showing a control flow of the vehicle ECU at the time of vehicle temporary stop in the eighth embodiment.

FIG. 12 is a flowchart showing a traveling control flow of the vehicle ECU in the ninth embodiment.

FIG. 13 is a diagram showing an example of increasing and changing a threshold voltage.

FIG. 14 is a diagram showing an example of increasing and changing a threshold voltage.

FIG. 15 is a diagram showing an example of temperature correction of a threshold voltage.

FIG. 16 is a flowchart showing a control flow during traveling of the vehicle ECU in the tenth embodiment.

FIG. 17 is a flowchart showing a control flow during traveling of the vehicle ECU in the eleventh embodiment.

FIG. 18 is a flowchart showing a control flow during traveling of the vehicle ECU in the twelfth embodiment.

[Explanation of symbols]

 1 Engine 2 Generator 3 Rectifier 4 Main Battery 5 Inverter 6 Motor 7 Transmission 8 Differential Gear (Diff) 9 Tire 10 SOC Meter 11 Current Sensor 12 Voltage Sensor 13 Temperature Sensor 14 Vehicle Speed Sensor 15 Vehicle ECU 16 Engine ECU 17 Field Controller 18 Auxiliary battery 19 DC-DC converter

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H02J 7/04 C 9060-5G

Claims (5)

[Claims] 1. An electric machine having a motor for driving a vehicle, a main battery for supplying electric power to the motor, and an engine-driven generator capable of supplying the motor with its generated output and charging the main battery with this generated output. A controller for an electric vehicle engine drive generator that controls the engine drive generator according to the state of charge of the main battery installed in a vehicle detects that the sulfation probability in the main battery has exceeded a certain level. And a full charge control means for charging the main battery until the battery is fully charged by activating the engine-driven generator when the possibility exceeds a predetermined level. A control device for an engine-driven generator for an electric vehicle. 2. The electric device according to claim 1, further comprising full charge control avoiding means for avoiding control of fully charging the main battery when the state of charge of the main battery is lower than a predetermined level. Control device for automobile engine driven generator. 3. The engine-driven power generation for an electric vehicle according to claim 1, wherein the full-charge control means relaxes the limitation of the voltage applied to the main battery when charging the main battery. Machine control device. 4. The control device according to claim 3, wherein when the full-charge control means reaches a voltage applied to the main battery to a voltage related to the limit and the charging current of the main battery becomes a predetermined value or less. A control device for an engine-driven generator for an electric vehicle, characterized in that the main battery is considered to have reached a fully charged state, and the relaxation of the above limitation is canceled. 5. The control device for an electric vehicle engine drive generator according to claim 3, wherein the full charge control means corrects the voltage related to the limit according to the temperature of the main battery. .