JPH09200908A - Drive system for hybrid automobile using high-temperature sodium secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the driving performance of an automobile by driving the automobile with a high-temperature sodium secondary battery at normality, and driving it in combination with an internal combustion engine or a large- capacitance capacitor only at a specified time. SOLUTION: The detection and measurement data of senors 8-10 which measure the temperature of a battery, the load of a motor 4, and the revolution of an internal combustion engine 6 are taken into a controller 12, and a driver is operated and controlled. That is, when the voltage or temperature of a secondary battery 1 is low, the drive of an electric motor 4 based on the secondary battery 1 is stopped, and the automobile is driven with an internal combustion engine. Moreover, the preservation of the temperature of the secondary battery 1 by the secondary battery 1 is stopped, and the temperature preservation of SE1 is performed by exhaust gas. Furthermore, in the case that the load of the electric motor 4 or the stepping of an acceleration pedal is larger than the specified value, the additional drive for an automobile is performed with an internal combustion engine or a large-capacitance capacitor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive device for a hybrid vehicle in which a high temperature sodium secondary battery and another prime mover or a large-capacity capacitor are provided as a drive source, and in particular, the drive device is discharged from an internal combustion engine as a drive source. The present invention relates to a drive device for a hybrid vehicle, which has a reduced exhaust gas emission amount and excellent driving performance.

[0002]

2. Description of the Related Art High-temperature sodium secondary batteries using sodium for the negative electrode and sulfur or halide for the positive electrode, and secondary batteries such as lithium batteries have a long service life and high efficiency and energy density. Recently, it has attracted attention and is expected to be used in electric power storage devices and electric vehicles.

On the other hand, electric vehicles have been attracting attention from the viewpoint of environmental measures against exhaust gas, etc., and various studies have been made for practical application. However, since the electric vehicle is currently inferior in driving performance, it is widely used in place of the current internal combustion engine vehicle, so that the capacity, output, life span, etc. of the battery used are large and should be improved. There are many problems. As a method for dealing with the problem, a hybrid vehicle in which driving of a motor by a battery and driving by an internal combustion engine are combined has attracted attention.

[0004]

By the way, in the conventional hybrid vehicle, since a lead-acid battery is mainly assumed as a battery to be used, the main drive of the vehicle is limited due to the limitation of its capacity and life. An internal combustion engine is used as a source, and a battery system is used to supplement the output shortage of the drive. Even if the use of a secondary battery, especially a high-temperature sodium secondary battery as a battery used in a hybrid vehicle drive device of such a system is considered, the secondary battery, especially a high-temperature sodium secondary battery is used in the configuration of the system. The excellent characteristics of the battery cannot be fully utilized.

On the other hand, Japanese Unexamined Patent Publication No. 7-264714 proposes a drive device for a hybrid vehicle using a sodium-sulfur battery, and the drive device for the proposed vehicle drives a generator using an internal combustion engine as a power source. To generate electric power and supply the electric power to the sodium-sulfur battery and the drive electric motor, and also supply the electric power from the sodium-sulfur battery to the electric motor to drive the electric motor with both drive sources. To do. As described above, since the electric motor is supplied with electric power from both the generator and the internal combustion engine, it can be driven with a large current.

[0006] However, the proposed automobile is constructed such that the generator is driven by the internal combustion engine, and the drive electric motor is rotated by the generator, and the internal combustion engine is usually in a constantly driven state. However, it is not preferable from the viewpoint of environmental measures such as exhaust gas. Further, since the generator mounted on the internal combustion engine is small and has a lower efficiency than a general generator, there is a drawback that the efficiency as a whole cannot be increased.

Further, the sodium-sulfur secondary battery is required to maintain the secondary battery at an appropriate high temperature, but the proposed vehicle drive device has not taken appropriate countermeasures for this. The present invention has been made in view of the above problems, and an object thereof is to determine the amount of exhaust gas of an internal combustion engine in a hybrid drive device using a high temperature sodium secondary battery and an internal combustion engine in combination. It is to provide a drive device for a hybrid vehicle having excellent driving performance, which is comparable to a vehicle using a general internal combustion engine while reducing the number of secondary batteries, and a secondary device such as a high temperature sodium secondary battery. An object of the present invention is to provide a highly efficient drive device for a hybrid vehicle, which is suitable for use of a battery.

[0008]

[Means for Solving the Problems] To achieve the above object,
The drive device for a hybrid vehicle of the present invention is a secondary battery,
A driving electric motor driven by the electric power of the secondary battery, an internal combustion engine or a large-capacity capacitor, a control device, and the temperature and voltage of the secondary battery and the load or accelerator pedal depression amount or depression of the motor. A sensor for detecting pressure, a means for keeping the secondary battery warm by the power of the secondary battery, and the controller detecting the temperature or voltage of the secondary battery. Respectively becomes a predetermined value or less, or when the load of the motor or the depression amount or depression pressure of the accelerator petal becomes a predetermined value or more, the internal combustion engine is driven or the large-capacity capacitor Characterized by comprising a control means for driving the motor with a discharge current of
During normal operation, the control device drives the vehicle by the electric motor with the secondary battery and idles the internal combustion engine at a predetermined speed, and the detected value of the temperature or voltage of the battery is predetermined. A control means for connecting the internal combustion engine to the drive system of the automobile when the motor load or the accelerator pedal depression amount or depression pressure exceeds a predetermined value. It is characterized by that.

In the hybrid vehicle drive device according to the present invention, the secondary battery is a high temperature sodium secondary battery housed in an adiabatic container, and the temperature and voltage of the secondary battery are the predetermined values. And a means for outputting the temperature and the voltage as separate signals and a means for displaying the drive state of the drive device when the temperature becomes the following, the temperature of the secondary battery becomes a predetermined value or less. And a predetermined value of the voltage of the secondary battery is necessary for starting or controlling the internal combustion engine. The voltage value corresponds to the remaining battery capacity for about one day.

Further, the hybrid vehicle drive device of the present invention is provided with means for detecting and displaying the number of revolutions of the internal combustion engine, and an electric heater for heating and keeping the battery in an adiabatic container. And a sensor for detecting the temperature and voltage of the high temperature sodium secondary battery, which is installed in the heat insulation container, and which is connected to a bypass pipe for exhaust gas of the internal combustion engine. The device
The internal combustion engine is operated when the temperature or voltage of the high-temperature sodium secondary battery becomes equal to or lower than a predetermined value, and the exhaust gas flowing through the bypass pipe is adjusted in order to heat / heat the high-temperature sodium secondary battery. And a means for controlling the controller to cool the high temperature sodium secondary battery by flowing air through the bypass pipe when the temperature of the battery exceeds a predetermined temperature. It is characterized by that.

In the hybrid vehicle drive apparatus according to the present invention constructed as described above, at the time of start, the drive motor is rotationally driven by the electric power of the secondary battery such as a high temperature NaS battery, and the temperature of the secondary battery is increased. Is feedback controlled. The battery capacity or the driving state of the secondary battery is calculated based on the detection of the voltage and the temperature of the secondary battery, and the driving state of the driving device is displayed according to the voltage or the temperature of the secondary battery. When the voltage or temperature of the secondary battery is low, the drive of the electric motor based on the secondary battery is stopped, the drive device of the automobile is driven by the internal combustion engine, and the secondary battery by the secondary battery is used. Stop the temperature maintenance of the secondary battery by the exhaust gas of the internal combustion engine, to determine whether or not to continue the operation, when the operation is not continued, the internal combustion engine is stopped,
Charging is required, and the temperature of the secondary battery is maintained by the power of the secondary battery.

Further, when it is judged that the state of the drive system of the automobile is normal, it is judged whether the load of the drive motor is large or the accelerator pedal is depressed greatly.
When the load of the drive motor or the depression of the accelerator pedal is larger than a predetermined value, the internal drive of the internal combustion engine or the large-capacity capacitor additionally drives the vehicle drive device. When the load on the electric motor or the depression of the accelerator pedal is small, it is determined whether or not the internal combustion engine needs to be driven, and at the same time, it is determined whether or not to continue the operation of the vehicle drive device. If it is not necessary to continue the operation of the vehicle drive device, or if it is not continued, the internal combustion engine or the internal combustion engine and the electric motor are stopped, and if the operation is continued, the control is continued.

Since a secondary battery such as a high-temperature sodium secondary battery or a lithium battery having high efficiency and high energy density is used as the battery, the efficiency of the drive device for the hybrid vehicle can be increased. Further, since the high temperature sodium secondary battery has an excellent charging characteristic that the polarization at the time of charging is small, the energy can be effectively recovered at the time of deceleration by using the regenerative brake, and the efficiency of the drive device for the hybrid vehicle can be improved. Can be further enhanced.

Furthermore, since the voltage of the sodium-sulfur battery rises at the end of charging, the state of charge can be known by measuring the voltage of the battery, and overcharging of the battery can be easily prevented. Furthermore, the high temperature sodium secondary battery needs to be heated and kept at a high temperature of about 300 ° C. during operation, and the heater power for heating and keeping the heat insulation container for the sodium secondary battery is not required. Preferably, at least when operating the electric motor for automobiles with the electric power of the battery,
Supplied from batteries. By doing so, the operating time of the internal combustion engine can be shortened as compared with the case where the internal combustion engine is always operated to heat the battery, which is effective in reducing the amount of exhaust gas.

Furthermore, in a secondary battery such as a high temperature sodium secondary battery, the electromotive force generally decreases as the discharge progresses, so by monitoring the voltage of the battery, the progress of the discharge,
That is, the remaining capacity can be known. Therefore, by detecting the voltage of the battery, and when the value becomes equal to or less than the predetermined value, the internal combustion engine is operated and the automobile is driven,
Problems due to insufficient battery capacity can be prevented. Further, according to this method, even when the battery capacity becomes less than or equal to a predetermined value, the vehicle can be operated as it is without stopping and charging the vehicle, and the charging of the battery can be limited only at night when the vehicle is not operated for a long time. In addition, the usability and driving performance of the drive device for a hybrid vehicle are significantly improved.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows an overall conceptual diagram of the hybrid vehicle drive device of the present embodiment. The high-temperature sodium secondary battery 1 is highly efficient and has a high energy density. , Sulfur is used for the positive electrode. The efficiency of the high temperature sodium-sulfur battery 1 depends on its charging / discharging method.
It is easy to keep above 5%. The high temperature sodium secondary battery 1 is housed in a heat insulating container 2, and normally, the heat insulating container 2 is a vacuum heat insulating container having excellent heat insulating performance.
The electric power of the high temperature sodium secondary battery 1 can be heated by an electric heater (not shown).
In the case of a sodium-sulfur battery, the temperature of the high temperature sodium battery 1 is usually set to about 330 ° C. The inverter 3 converts the DC power of the secondary battery 1 into AC power and transmits the AC power to an electric motor 4 for a vehicle to operate the electric motor 4 or use a regenerative brake or the like. It has a function of converting the AC power generated by the electric motor 4 into DC and charging the secondary battery 1. The inverter 3 can also be used when the battery is charged by external power when the vehicle is stopped. Resistor 5
This is for consuming a part of the electric power as heat when the electric power generated by the regenerative brake is too large. An internal combustion engine 6 such as a gasoline engine drives the automobile in place of the electric motor 4 or together with the electric motor 4 as a drive source for the automobile. Electric power for igniting or controlling the internal combustion engine 6 is also supplied from the secondary battery 1, but a lead battery or the like may be installed separately depending on the case. The electric component 7 is driven by the electric power of the secondary battery 1, and when the internal combustion engine 6 and the electric component 7 are driven by the electric power from the secondary battery 1, the voltage of the secondary battery 1 is changed as necessary. It is supplied after being converted into a predetermined voltage by a DC-DC converter or the like.

Further, the detection measurement from the sensor 8 for measuring the temperature of the battery, the sensor 9 for measuring the load of the motor 4, and the sensor 10 for measuring the rotational speed of the internal combustion engine 6. The measured data is taken into the controller 12, which is a control device, together with the voltage of the secondary battery 1 supplied through the measurement line 11, and the drive device for the hybrid vehicle is operated and controlled. A signal line 13 for control also connects the electric transmission 7, the inverter 3, the internal combustion engine 6 and the controller 12. Bypass pipes 14a, 14b, 14c are connected to an exhaust gas pipe 14 connected to the internal combustion engine 6, and the bypass pipes 14b, 14c are connected to the heat insulating container 2. The bypass pipes 14a, 14b,
14c is provided with adjusting valves 15, 16 and 17, and by adjusting the adjusting valves 15 and 16, the amount of exhaust gas from the internal combustion engine 6 to the heat insulating container 2 is adjusted to keep the secondary battery 1 warm. The state can be adjusted.

Further, when the temperature of the secondary battery 1 becomes too high, for example, about 400 ° C. while continuing the high output operation, the adjusting valve 17 is opened to introduce the outside air, The secondary battery 1 can also be cooled. FIG. 2 shows another embodiment of a hybrid vehicle drive device using a large-capacity capacitor 20 in place of the internal combustion engine 6 of the embodiment of FIG. 1, and the same members as those of FIG. 1 are the same. And the description thereof will be omitted.

In FIG. 2, the large-capacity capacitor 20 is
Normally, the high-temperature sodium secondary battery 1 is charged, and when the output shortage of the secondary battery 1 becomes a problem, the discharge current is supplied to the electric motor 4 via the inverter 3.
The regenerative energy of the electric motor 4 is converted into a large-capacity capacitor 20.
You can also store it. FIG. 3 shows the concept of the control flow of the control device for the hybrid vehicle drive device according to the two embodiments.

At the start of the automobile, in step 100, the electric motor 4 is rotationally driven by the electric power of the secondary battery 1 such as a high temperature NaS battery, and the secondary battery 1 is kept warm for keeping the secondary battery 1 warm. The temperature is controlled by feedback. In steps 101 to 106, the battery capacity or the driving state of the secondary battery 1 is calculated based on the detection of the voltage and the temperature of the secondary battery 1, and the driving device (according to the voltage or the temperature of the secondary battery 1 is calculated. System) drive status is displayed.

When the internal combustion engine 6 is installed (step 107) and the voltage or temperature of the secondary battery 1 is low, in step 110 the drive of the electric motor 4 based on the secondary battery 1 is stopped. The internal combustion engine 6 drives the drive device of the automobile, the secondary battery 1 stops holding the temperature of the secondary battery 1, and the exhaust gas of the internal combustion engine 6 holds the temperature of the secondary battery 1. In step 111, it is determined whether or not to continue the operation. If the operation is not to be continued, the process proceeds to step 112, the internal combustion engine 6 is stopped, and charging is required, and the secondary battery 1 is displayed.
The power of the secondary battery holds the temperature of the secondary battery.

Further, if it is determined in step 113 that the state of the vehicle drive system (system) is normal, in step 114 it is determined whether the load on the electric motor 4 is large or the accelerator pedal is depressed. If it is determined that the load on the electric motor 4 or the depression of the accelerator pedal is larger than a predetermined value, the process proceeds to step 115, and the internal combustion engine 6 or the large-capacity capacitor 20 additionally drives the vehicle drive device. If the load on the electric motor 3 or the depression of the accelerator pedal is small, the process proceeds to steps 116 to 119. If the large-capacity capacitor 20 is installed, the large-capacity capacitor 20 is installed.
When the internal combustion engine 6 is mounted by stopping the discharge from the vehicle to the electric motor 4, it is determined in steps 117 to 120 whether the internal combustion engine 6 needs to be operated, and
It is judged whether or not the operation of the vehicle drive device is continued, and it is not necessary to operate the internal combustion engine 6 or the vehicle drive device, or if the operation is not continued, the internal combustion engine 6 or the internal combustion engine is executed in step 118 or step 120. 6 to stop the electric motor 4 and continue the operation, step 1
Returning to 00, the control flow is continued. As a control method, it is possible to keep the internal combustion engine 6 constantly operating and connect it to the vehicle drive system only when necessary. When the vehicle is stopped, a message prompting charging is displayed, and the temperature of the secondary battery 1 is maintained by the power of the secondary battery 1.

Specifically, a 37.5 kAh NaS battery (battery body weight of about 400
kg) and a 1000 cc gasoline engine mounted on the hybrid vehicle drive device of the present embodiment,
The mileage in 10 modes per charge is about 250km,
Acceleration is similar to that of a 2000cc gasoline engine, and the exhaust gas amount is 1/10 or less. Further, the battery efficiency considering the conversion efficiency at the time of heat retention and charging / discharging of the secondary battery 1 can be about 75% or more, and the running efficiency in 10 mode is about 4 k.
It becomes m / kWh. This value is comparable to a normal gasoline engine car.

The electromotive force of the sodium-sulfur secondary battery 1 is constant until the composition of the positive electrode is in the state of Na ₂ S ₅ , and as the discharge progresses, the composition of the positive electrode becomes Na ₂ S ₄ , Na.
_The electromotive force decreases as it changes to ₂ S ₃ . The electromotive force decreases with discharge in the same manner as in other high temperature sodium batteries. Therefore, by measuring the electromotive force or the current and voltage of the battery, it is possible to know the remaining capacity of the secondary battery 1. Is. Utilizing this property, when the voltage or temperature of the secondary battery 1 falls below a predetermined value, the internal combustion engine 6 is operated and the automobile is driven instead of the electric motor 4. For example, the optimum temperature of the secondary battery 1 is preferably in a range where the efficiency of the sodium-sulfur battery does not decrease so much, and the limit value is about 300 ° C. Further, the limit value of the electromotive force of the secondary battery 1 is also related to the total capacity of the secondary battery 1 mounted on an automobile,
In the case of sodium-sulfur batteries, the voltage is about 1.8V per battery. By doing so, there is no need to install more batteries than necessary, fearing that the drivable distance per charge will be insufficient. As a result, the problem of insufficient traveling distance, which is generally regarded as a drawback of electric vehicles as compared with internal combustion engine vehicles, can be covered.

Further, when the internal combustion engine 6 is operating, the exhaust gas thereof is used to heat and keep the temperature of the secondary battery 1, so that the efficiency of the drive device of the automobile is improved.
In particular, when the voltage of the secondary battery 1 falls below a predetermined voltage, it is desirable to stop heating the secondary battery 1 by an electric heater (not shown) arranged in the heat insulating container 2. The vehicle drive device according to the present embodiment outputs the different signals depending on whether the voltage of the secondary battery 1 is lower than a predetermined value or the temperature is lower than the predetermined value. The state of the device can be accurately determined. When the load on the electric motor 4 or the depression of the accelerator pedal exceeds a predetermined value, the internal combustion engine 6 or the large-capacity capacitor 20 is operated,
By compensating for the power, the power that is a drawback of electric vehicles
You can cover the shortage. Further, by measuring the rotational speed of the internal combustion engine 6, it is possible to know the exhaust gas amount, and it is possible to take measures such as a warning for reducing the exhaust gas amount, or an operation restriction of the internal combustion engine 6.

From the viewpoint of reducing the exhaust gas amount, it is important that the voltage of the secondary battery 1 does not fall below a predetermined value as much as possible, and the voltage of the secondary battery 1 falls below a predetermined value. It is desirable not only to charge the battery but also to charge it when the vehicle is stopped for a long time, such as at night. In the sodium-sulfur battery, sulfur deposits on the positive electrode at the end of charging and the charging voltage rises.Therefore, by controlling the charging voltage, charging naturally stops, and there is no risk of overcharging, so the vehicle can be stopped for a long time. Especially suitable for charging when. For example,
In the case of a sodium-sulfur battery, the upper limit of the charging voltage of the secondary battery 1 may be about 2.5 V per battery.

Further, even when the voltage of the secondary battery 1 becomes a predetermined value or less during the operation of the drive device, if the internal combustion engine 6 needs to continue the operation of the vehicle, the internal combustion engine It is necessary to secure the electric power for igniting and controlling 6. The operating period at this time can be assumed to be about one day, and the electromotive force of the secondary battery 1 corresponding to the amount of remaining power required for this purpose is determined by the displacement of the vehicle, the operating mode,
Although it depends on the capacity of the battery installed in the vehicle, the voltage of the sodium-sulfur battery is about 1.8V per battery. According to this method, it is not necessary to install a lead battery or a generator in the internal combustion engine 6 as usual.

Further, in the case where it is necessary to frequently start and stop the vehicle, the internal combustion engine 6 is idled at an appropriate speed and the load on the electric motor 4 and the accelerator pedal are depressed. When the amount exceeds a predetermined amount, the internal combustion engine 6 can be connected to a drive system so that the electric motor 4 and the internal combustion engine 6 can be used together to drive an automobile. With this method as well, the exhaust gas amount is reduced as compared with the case where the engine speed of the internal combustion engine 6 is increased / decreased and start / stop is repeated. However, in order to drastically reduce the amount of exhaust gas, the operation in this mode should be kept to the minimum necessary, and when the motor load or the accelerator pedal depression amount or depression pressure becomes as large as possible. It is desirable to operate the internal combustion engine 6 in the mode.

The same as the above can be achieved by a system combining a secondary battery such as a high temperature sodium battery and a large-capacity capacitor instead of the internal combustion engine.
Or, when the accelerator pedal is stepped on more than a predetermined value, the large-capacity capacitor is discharged and the motor is driven by the discharge current, so that there is no time delay and acceleration,
Can cope with the start. In addition, as a large-capacity capacitor,
An electric double layer capacitor in which an activated carbon electrode and an electrolytic solution are combined can be used.

When the battery voltage drops, it is necessary to notify the driver of the necessity of charging by displaying a message to that effect. In this case, in order to charge the battery only at night, the remaining capacity of the internal combustion engine 6 is set so that the secondary battery 1 can supply electric power necessary for starting and controlling the internal combustion engine 6 even during operation after the battery voltage drops. The operation of the internal combustion engine 6 and the battery voltage drop display may be performed at the time when the power required for startup, control, etc. is about one day or less. Further, when the vehicle is stopped for a long time, the heat of the secondary battery 1 needs to be covered by the electric power of the secondary battery itself such as a high temperature sodium secondary battery, and it is better not to use the internal combustion engine 6 as much as possible for the exhaust gas. Since it is preferable as a countermeasure, it is desirable to display a message prompting the driver to charge the battery. In the case of sodium-sulfur batteries, the battery voltage rises at the end of charging as described above.Therefore, by controlling the charging voltage below a specified value, charging stops by itself at the end of charging, and there is no concern of overcharging. There is.

Further, it is desirable that the secondary battery 1 is kept at a temperature by its own electric power during the normal operation, but when the residual capacity of the secondary battery 1 is lowered or the heat insulating container 2 is abnormal. Temperature drops. Therefore, it is necessary to detect the battery temperature and operate the internal combustion engine 6 to heat the secondary battery 1 when the value becomes equal to or lower than a predetermined value. At this time, the exhaust gas bypass pipe 1 is placed in the heat insulating container 2.
It is particularly preferable to connect 4a and 14b to drive the vehicle with the power of the internal combustion engine 6 and heat the secondary battery 1 with the exhaust gas in order to increase the efficiency of the system.
Further, even when the battery voltage drops, the secondary battery 1
It is desirable to stop the heating and heat retention by the method and switch to the method of heating the secondary battery 1 by the exhaust gas. When the method of heating the secondary battery 1 with the exhaust gas is used, the efficiency of the system is higher than that of the case where the generator connected to the internal combustion engine 6 is operated to generate electricity and the electric power is used for heating. There is an advantage that the generator connected to 6 is unnecessary and the system configuration is simple. In the structure in which the exhaust gas bypass pipe is connected to the heat insulating container 2, when the temperature of the secondary battery 1 becomes equal to or higher than a predetermined temperature, such as when the secondary battery 1 is discharged at a high output, air is supplied to the bypass pipe 14b. There is also an advantage that the secondary battery 1 can be cooled by flowing the liquid, and the temperature control of the secondary battery 1 becomes easy.

Furthermore, when the battery temperature becomes lower than a predetermined value, a signal other than the battery voltage drop can be output to accurately display the state of the driving device (system), and to respond accurately according to the state. Is possible. That is, the display of battery voltage drop + battery temperature normal means that the battery capacity is insufficient, and the display of battery voltage drop + battery temperature decrease means a significant decrease in battery capacity. The normal battery voltage + normal battery temperature display indicates that the system is normal, and the normal battery voltage + low battery temperature display indicates a system abnormality such as a malfunction of the heat insulating container. By accurately displaying the state of the drive device (system) in this way, the usability of the drive device for a hybrid vehicle is improved.

Furthermore, an electric motor driven by the secondary battery 1
Detecting the load on the actuator 4 or stepping on the accelerator pedal,
By operating the internal combustion engine 6 or discharging the large-capacity capacitor 20 when the load exceeds the predetermined value or the accelerator pedal depression amount or depression pressure is reached, high-speed operation can be performed when the vehicle is started or when a steep slope is climbed. It is possible to avoid troubles due to insufficient battery output during traveling, etc., and improve the driving performance of the hybrid vehicle drive device.

Furthermore, since the exhaust gas emission amount can be known by detecting the rotational speed of the internal combustion engine, this is displayed to warn the driver and the operation of the internal combustion engine is restricted if necessary. As a result, the amount of exhaust gas can be reduced. In addition, as a variation of the exhaust gas countermeasure, a case in which the regulated amount of the exhaust gas differs depending on the place, such as a suburb and a city, can be considered. In such a case, a system that manually switches between battery drive and internal combustion engine drive is preferable.

As described above, the high temperature sodium secondary battery typified by the NaS battery has a higher energy density than a lead battery and thus can have a high capacity, and has a long life and a capacity even after repeated deep charge and discharge. Does not decrease, the mileage per charge can be relatively large when applied to an electric vehicle, but the internal resistance is relatively high, which makes it difficult to operate at high output. Driving an electric vehicle with an electric motor using only a secondary battery is difficult in terms of acceleration and high-speed traveling. However, in the hybrid vehicle drive device of the present invention, during startup, acceleration, and high-speed traveling When a large load is applied to the electric motor, such as when climbing a slope, the internal combustion engine and large-capacity capacitor can automatically operate to compensate for the insufficient power, resulting in excellent driving performance. And 1 travel distance per charging long the hybrid vehicle drive device can be realized.

Although the two embodiments of the present invention have been described in detail above, the present invention is not limited to the above-mentioned embodiments, and does not depart from the spirit of the present invention described in the claims. , Various changes can be made in the design.

[0037]

As can be understood from the above description, the drive system for a hybrid vehicle of the present invention uses a high temperature sodium secondary battery in combination with an internal combustion engine or a large capacity capacitor,
At normal times, the automobile is driven by the high temperature sodium secondary battery, and the driving performance of the automobile can be improved by using the configuration in which the automobile is driven together with the internal combustion engine or the large capacity capacitor only at a specific time. It is possible to realize a highly efficient hybrid vehicle drive device that is suitable for use with batteries. In addition, a hybrid vehicle that is effective as an exhaust gas countermeasure will be realized.

[Brief description of drawings]

FIG. 1 is an overall conceptual diagram of a hybrid vehicle drive device (a combination of a high temperature sodium secondary battery and an internal combustion engine) according to an embodiment of the present invention.

FIG. 2 is an overall conceptual diagram of a hybrid vehicle drive device (combined use of a high temperature sodium secondary battery and a large capacity capacitor) according to another embodiment of the present invention.

FIG. 3 is a control flow chart of the hybrid vehicle drive device of FIGS. 1 and 2.

[Explanation of symbols]

1: High-temperature sodium secondary battery, 3: Inverter, 4: Motor, 6: Internal combustion engine, 8: Temperature sensor, 9: Motor load sensor, 20: Large capacity capacitor

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Hiroshi Kaneko 2477 Takaba, Hitachinaka City, Ibaraki Prefecture Hitachi Car Engineering Co., Ltd.

Claims (10)

[Claims] 1. A secondary battery, an electric motor for driving which is driven by the electric power of the secondary battery, an internal combustion engine or a large-capacity capacitor,
In a hybrid vehicle drive device, which includes a control device, and sensors for detecting the temperature and voltage of the secondary battery and the amount of depression or the amount of depression of the load or accelerator pedal of the electric motor, Means for keeping the secondary battery warm with the power of the secondary battery, and when the detected value of the temperature or voltage of the secondary battery becomes a predetermined value or less, or the load of the motor or the accelerator pedal. When the depression amount or depression pressure of is equal to or more than a predetermined value, the control device includes a control unit that drives the internal combustion engine or drives the electric motor with a discharge current of the large capacity capacitor. Drive system for hybrid vehicles. 2. A secondary battery, an electric motor for driving which is driven by the electric power of the secondary battery, an internal combustion engine, a control device, and a temperature and voltage of the secondary battery and a load or an accelerator petal of the motor. In a hybrid vehicle drive device including sensors for detecting the stepping amount or the stepping pressure, the control device drives the vehicle by an electric motor by the secondary battery during normal operation and the internal combustion engine. When the engine is idled at a predetermined speed and the detected value of the temperature or voltage of the battery becomes a predetermined value or less, or the load of the motor or the depression amount or depression pressure of the accelerator petal is A drive device for a hybrid vehicle, comprising means for connecting the internal combustion engine to a drive system of a vehicle when the value exceeds a predetermined value. 3. The hybrid vehicle drive device according to claim 1, wherein the secondary battery is a high temperature sodium secondary battery housed in a heat insulating container. 4. The controller drives the driving device and means for outputting the temperature and the voltage of the secondary battery as separate signals when the temperature and the voltage of the secondary battery become equal to or lower than the predetermined values, respectively. The hybrid vehicle drive device according to claim 1 or 2, further comprising means for displaying a state. 5. A means for heating and maintaining the temperature of the secondary battery by using exhaust gas of the internal combustion engine when the temperature of the secondary battery falls below a predetermined value.
Alternatively, the hybrid vehicle drive device according to item 2. 6. The predetermined value of the voltage of the secondary battery is
The control device for a hybrid vehicle according to claim 4, wherein the voltage value is a voltage value corresponding to a remaining battery capacity of about one day required to start or control the internal combustion engine. 7. The drive system for a hybrid vehicle according to claim 1, further comprising means for detecting and displaying the number of revolutions of the internal combustion engine. 8. A hybrid vehicle drive device comprising a high temperature sodium secondary battery housed in a heat insulating container, an electric motor driven by the electric power of the battery, an internal combustion engine, and a control device, wherein An electric heater for heating and keeping the battery warm is installed, a bypass pipe for exhaust gas of the internal combustion engine is connected, and a sensor for detecting the temperature and voltage of the high temperature sodium secondary battery is provided. A hybrid vehicle drive device characterized in that 9. The control device operates the internal combustion engine when the temperature or voltage of the high temperature sodium secondary battery becomes a predetermined value or less, and heats and keeps the temperature of the high temperature sodium secondary battery. 9. The drive device for a hybrid vehicle according to claim 8, further comprising control means for adjusting exhaust gas flowing through the bypass pipe. 10. The control device comprises means for controlling to cool the high-temperature sodium secondary battery by flowing air through the bypass pipe when the temperature of the battery exceeds a predetermined temperature. The drive system for a hybrid vehicle according to claim 8.