JP2012126327A - Running control apparatus of hybrid electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a running control apparatus of a hybrid electric vehicle which can efficiently drive an engine and an electric motor as a whole and then can achieve fuel consumption improvement.SOLUTION: When SOC (State of Charge) of a battery 18 is enough, the skip control mode to change the speed steps by jumping over by one step of transmission 8 is executed, and in a normal control mode, the rotation range of the engine 2 is shifted to the low rotation side by selecting a fourth velocity or a sixth velocity in the area where a third velocity or a fifth velocity should be selected, and the fuel consumption amount is decreased. As a result, the requested torque of the driver is achieved by compensating the shortage of the caused engine torque by the torque increase of electric motor 6.

Description

  The present invention relates to a travel control device for a hybrid electric vehicle, and more particularly, a travel control device for a hybrid electric vehicle that achieves a reduction in fuel consumption by driving the engine in a low fuel consumption region when the engine and an electric motor are used in combination. About.

  2. Description of the Related Art Conventionally, so-called parallel hybrid electric vehicles have been developed and put into practical use in which an engine and an electric motor are mounted on a vehicle and the driving force of the engine and the driving force of the electric motor can be transmitted to the driving wheels of the vehicle. As one of this type of parallel hybrid electric vehicle, there has been proposed one in which an electric motor is connected to drive wheels via a transmission and an engine is connected to the electric motor via a clutch. In the hybrid electric vehicle, when the clutch is disengaged, the driving force of the electric motor is transmitted to the driving wheel through the transmission to drive the vehicle, and when the clutch is connected, the driving force of the engine or the driving force of the engine and the electric motor is transmitted to the driving wheel. Then, the vehicle is driven by being transmitted to the drive wheels.

  In the combined driving of the engine and the motor in which the vehicle is driven by the driving force of the engine and the electric motor, it is necessary to optimize the driving force distribution for efficient operation of the engine and the electric motor. A technique has been proposed (see, for example, Patent Document 1). In Patent Document 1, when the gear stage of the transmission is a predetermined gear stage having the highest transmission efficiency, the maximum assist value of the motor that assists the driving force of the engine is set larger than when the gear stage is other than the predetermined gear stage. Shifting from a predetermined gear stage with good transmission efficiency to another gear stage is suppressed to improve transmission efficiency of the entire transmission.

JP 2006-280049 A

However, the hybrid electric vehicle described in Patent Document 1 only optimizes the driving force distribution when the required torque according to the driver's accelerator operation is distributed to the engine side and the electric motor side. For this reason, even if the optimal driving force distribution is found and the engine and motor torques are set, there is a limit to improving the efficiency of the engine and motor as a whole. Measures were desired.
The present invention has been made to solve such problems, and the object of the present invention is to provide a hybrid electric vehicle that can efficiently operate the engine and the electric motor as a whole, thereby achieving improvement in fuel consumption. The object is to provide a travel control device.

  In order to achieve the above object, a first aspect of the present invention provides a travel control device for a hybrid electric vehicle that travels by transmitting torques of an engine and an electric motor to drive wheels via a transmission having a plurality of shift stages. In response to this, a normal transmission means for sequentially switching the respective gear stages of the transmission and a skip for performing a skip gear shift for switching the gear stages so as to jump over a specific gear stage among the respective gear stages of the transmission according to the vehicle speed. The normal control mode is set when the speed change means, the remaining capacity detection means for detecting the remaining capacity of the battery for supplying electric power to the electric motor, and the remaining capacity of the battery detected by the remaining capacity detection means is less than a preset judgment value. Select and shift the transmission with the normal transmission means, and when the remaining battery capacity is greater than the judgment value, select the skip control mode and skip shift Mode switching means for shifting the transmission according to the stage, and the driver's required torque is distributed to the engine side and the motor side, and the engine and motor torque is controlled based on the torque distribution, while the skip control mode is selected by the mode switching means And a torque control means for correcting the torque of the motor to an increase side to compensate for an engine torque shortage accompanying a shift of the engine rotation range to a low speed side when the skip speed change means is executed. It is provided.

According to a second aspect of the present invention, in the first aspect, when the torque control means causes the engine to generate torque on the drive side as the vehicle accelerates, the engine efficiency decreases as a result of the skip shift by the skip control means. When the engine torque decreases to a significant range, the engine torque is increased and the torque of the motor is corrected to the decrease side by the amount of torque increase.
According to a third aspect of the present invention, in the first or second aspect, the skip transmission means selectively executes a plurality of skip shifts set so as to jump over different specific shift stages among the respective shift stages. Yes, on the basis of the shift speed of the transmission when the mode switching means selects the skip control mode, a skip shift having the shift speed as the specific shift speed is selected from a plurality of skip shift speeds, and the selected skip shift speed is determined as the skip shift speed change means. To be executed.

As described above, according to the traveling control apparatus for a hybrid electric vehicle according to the first aspect of the present invention, when the remaining capacity of the battery is less than the determination value, the normal control mode is selected and each shift stage of the transmission is selected according to the vehicle speed. On the other hand, when the remaining capacity of the battery is equal to or greater than the judgment value, the skip control mode is selected to switch each shift stage so as to jump over the specific shift stage, and the torque due to the decrease in engine rotation at this time In order to compensate for the shortage, the motor torque was corrected to the increasing side.
Therefore, when the skip shift is being executed in the skip control mode, the shift stage on the high speed gear side is selected compared to the shift stage in the normal control mode, and the engine speed range shifts to the low rotation side. Therefore, fuel consumption can be reduced. For example, when accelerating the vehicle, the fuel consumption is directly reduced by shifting the engine rotation range to the low rotation side, and when decelerating the motor, the motor brake is reduced by the shift of the engine rotation range to the low rotation side. Since the regenerative torque of the engine can be increased, the fuel consumption of the engine is indirectly reduced by using the generated power when the motor of the motor is operated.
Since the engine torque deficiency caused by the selection of the gear position on the high-speed gear side is compensated by the increase in the torque of the motor, the torque required by the driver can be reliably achieved, and as a result, the engine and the motor can be more efficiently improved as a whole. Driving improves fuel efficiency.

According to the traveling control device for a hybrid electric vehicle of the invention of claim 2, in addition to claim 1, to the region where the engine efficiency is significantly reduced as a result of the skip shift at the time of vehicle acceleration in which the engine generates driving torque. When the engine torque decreases, the engine torque is increased and the motor torque is corrected to the lower side. For this reason, the fuel consumption of the engine and the driving efficiency can be achieved at a high level, and further improvement in fuel consumption can be achieved.
According to the travel control device for a hybrid electric vehicle of the invention of claim 3, in addition to claim 1 or 2, the shift stage is set as a specific shift stage based on the shift stage of the transmission at the time when the skip control mode is selected. The skip shift is selected from a plurality of skip shifts and executed by the skip shift means. Therefore, even if the skip control mode is started at any gear stage, the engine speed range is immediately shifted to the low speed side by skipping that gear stage as a specific gear stage and selecting the gear stage on the high speed gear side. Therefore, as a result, the fuel consumption reduction effect can be reliably obtained even in a short time acceleration.

1 is an overall configuration diagram illustrating a travel control device for a hybrid electric vehicle according to an embodiment. It is a figure which shows a normal shift map and a skip shift map. It is a flowchart which shows the mode switching routine which ECU performs. It is a time chart which shows the speed change state at the time of vehicle acceleration by normal control mode and skip control mode. FIG. 6 is a characteristic diagram comparing an engine operating region and a torque assist situation of an electric motor at each gear position in a normal control mode and a skip control mode. It is the figure which showed the characteristic of the fuel consumption per hour of an engine, and the operating efficiency corresponding to FIG. It is a figure which shows the 1st and 2nd skip shift map used in another example.

Hereinafter, an embodiment of a travel control device for a hybrid electric vehicle embodying the present invention will be described.
FIG. 1 is an overall configuration diagram showing a travel control device of a hybrid electric vehicle 1 of the present embodiment.
The hybrid electric vehicle 1 is a so-called parallel type hybrid vehicle, and is configured as a truck in this embodiment. In the following description, the hybrid electric vehicle 1 may be referred to as a vehicle.
An input shaft of a clutch 4 is connected to an output shaft of a diesel engine (hereinafter referred to as an engine) 2, and a rotary shaft of an electric motor 6 that can generate electric power, such as a permanent magnet synchronous motor, is connected to the output shaft of the clutch 4. The input shaft of the automatic transmission 8 is connected via The automatic transmission 8 automates the connection / disconnection operation of the clutch 4 and the switching operation of the shift stage on the basis of a general manual transmission. The second speed is set as the starting stage. Of course, the gear stage of the transmission 8 is not limited to this, and can be arbitrarily changed.

The output shaft of the transmission 8 is connected to the left and right drive wheels 16 via a propeller shaft 10, a differential device 12 and a drive shaft 14. Accordingly, when the clutch 4 is disengaged, only the electric motor 6 is connected to the drive wheel 16 side via the transmission 8, and when the clutch 4 is connected, both the engine 2 and the electric motor 6 are connected to the drive wheel 16 side via the transmission 8. The
The electric motor 6 operates as a motor when the DC power stored in the traveling battery 18 is converted into AC power by the inverter 20 and supplied thereto, and the driving torque of the electric motor 6 is appropriately changed by the transmission 8 and then the driving wheels 16 are changed. The vehicle 1 is caused to travel by being transmitted to the vehicle. Further, during coasting operation in which the vehicle 1 decelerates when the accelerator is off, the electric motor 6 operates as a generator to generate AC power, and the vehicle 1 is decelerated while generating a regenerative torque and applying a braking force to the drive wheels 16. Let Then, the generated AC power is converted into DC power by the inverter 20 and then charged to the battery 18, whereby the deceleration energy of the vehicle 1 is recovered as electric energy and is then effectively used for traveling by the electric motor 6. .

  On the other hand, the driving force of the engine 2 is transmitted to the transmission 8 via the rotating shaft of the electric motor 6 when the clutch 4 is connected, and is transmitted to the drive wheels 16 after being appropriately shifted. Accordingly, when the driving force of the engine 2 is transmitted to the driving wheels 16 and the electric motor 6 does not operate as a motor, only the driving force of the engine 2 is transmitted to the driving wheels 16 via the transmission 8, and the electric motor When the motor 6 operates as a motor, the driving forces of the engine 2 and the electric motor 6 are both transmitted to the driving wheel 16 via the transmission 8.

When the remaining capacity (SOC: State Of Charge) of the battery 18 decreases and the battery 18 needs to be charged, the motor 6 operates as a generator even when the vehicle 1 is traveling, and the engine 2 is driven. Electric power is generated by operating the electric motor 6 using a part of the force, and the battery 18 is charged after the generated AC power is converted into DC power by the inverter 20.
The vehicle ECU 22 controls the connection / disconnection control of the clutch 4 and the transmission / reception control of the transmission 8 by controlling driving of an actuator (not shown) according to the operation state of the vehicle 1 and the engine 2 and information from the engine ECU 24, the inverter ECU 26, and the battery ECU 28. In addition to performing gear change control, integrated control for appropriately operating the engine 2 and the electric motor 6 is performed in accordance with these control states and various operation states such as starting, acceleration, and deceleration of the vehicle 1.

When performing such control, the vehicle ECU 22 detects the operation amount Acc of the accelerator pedal 30, the vehicle speed sensor 34 that detects the speed V of the vehicle 1, and the rotational speed N of the output shaft of the engine 2. Detection results of the engine rotation speed sensor 35 for detecting the motor, the motor rotation speed sensor 36 for detecting the rotation speed N of the electric motor 6 as the input rotation speed of the transmission 8, the brake sensor 40 for detecting the depression operation of the brake pedal 39, etc. Based on this, the required torque required for traveling of the vehicle 1 is calculated, and this required torque is distributed to the torque generated by the engine 2 and the torque generated by the electric motor 6.
In parallel with this, the travel mode (engine alone travel, motor alone travel, engine / motor combined travel) based on the required torque, the traveling state of the vehicle 1, the operating state of the engine 2 and the electric motor 6, or the SOC of the battery 18 and the like. Is selected, a command is output to the engine ECU 24 and the inverter ECU 26 to execute the selected travel mode, and the shift control of the transmission 8 is appropriately executed.
The engine ECU 24 operates the engine 2 by executing injection amount control and injection timing control so as to achieve the travel mode and engine torque set by the vehicle ECU 22.
Further, the inverter ECU 26 drives and controls the inverter 20 to operate the motor 6 or the generator so as to achieve the travel mode and the torque of the motor 6 set by the vehicle ECU 22.

The battery ECU 28 detects the temperature of the battery 18, the voltage of the battery 18, the current flowing between the inverter 20 and the battery 18, and obtains the SOC of the battery 18 from these detection results, and detects the obtained SOC. The result is output to the vehicle ECU 22 (remaining capacity detection means).
By the way, as described above, in the combined driving of the engine and the electric motor, the required torque is distributed to the engine side and the electric motor side to operate the engine 2 and the electric motor 6, and as one of the techniques for optimizing the driving force distribution at this time Patent Document 1 has been proposed. However, as described in [Problems to be Solved by the Invention], the efficiency of the engine 2 and the electric motor 6 as a whole is improved by simply optimizing the driving force distribution as in the technique of Patent Document 1. There were limits to achieving improvements in fuel economy.
Here, the present inventor preferably operates the engine 2 in a low rotation range in view of the fuel consumption characteristics of the engine 2 in the combined driving of the engine and the electric motor, and the SOC of the battery 18 is sufficient for the insufficient torque due to this. It has been noted that if it can be compensated by an increase in the torque of the electric motor 6 and that the operating range of the engine 2 can be easily switched to the low speed side by shifting beyond each gear stage of the transmission 8. Based on such knowledge, in this embodiment, in addition to the normal control mode, the speed of the engine 18 generated at this time is changed by jumping over one shift speed on condition that the SOC of the battery 18 is sufficient. Control for compensating for the shortage by increasing the torque of the electric motor 6 (hereinafter, this control is referred to as a skip control mode with respect to the normal control mode) is executed, and the skip control mode will be described in detail below.

As described above, since the shift control of the transmission 8 is different from the normal control mode in the skip control mode, a shift map for the skip control mode different from the normal shift map is set in advance. Therefore, first, a description will be given according to FIG. 2 while comparing the shift maps of both control modes.
Each shift map is set so as to derive the target shift stage according to the vehicle speed V and the accelerator operation amount Acc, and is stored in the vehicle ECU 22 in advance. As is well known, in the normal shift map, regions of all shift stages from the first speed to the sixth speed that can be achieved by the transmission 8 are set.
On the other hand, in the skip shift map, the third speed (specific shift speed) area of the normal shift map is set as the fourth speed area, and the fifth speed (specific shift speed) area of the normal shift map is the sixth speed map. It is set as a speed area. Therefore, according to the skip shift map, the shift is performed by jumping over the third speed and the fifth speed, and as a result, in the region where the third speed and the fifth speed are achieved in the normal shift map, the skip shift map The 4th speed and the 6th speed will be achieved, respectively.

Note that the two shift maps shown in the figure are for upshifting, and although not shown, the shiftdown shift maps are separately provided so as to form a predetermined hysteresis with respect to the shiftup shift map. Is set. In this embodiment, the vehicle ECU 22 when executing shift control based on the normal shift map functions as a normal shift unit, and the vehicle ECU 22 when executing shift control based on the skip shift map functions as a skip shift unit. .
The vehicle ECU 22 executes the mode switching routine shown in FIG. 3 at a predetermined control interval when the engine / motor combined driving is selected as the driving mode using the shift map set as described above.
First, in step S2, it is determined whether or not it is currently in the normal control mode. When the normal control mode is in effect, a Yes (positive) determination is made and the routine proceeds to step S4, where it is determined whether or not the SOC of the battery 18 is greater than or equal to a preset upper limit determination value SOCup (for example, 50%). . When the determination is No (No), the routine is once terminated. On the other hand, when the determination is Yes, the routine is terminated after the skip control mode is executed in step S6 (mode switching means).

When the determination in step S2 is No, the process proceeds to step S8, where it is determined whether the SOC of the battery 18 is less than a preset lower limit determination value SOCdw (for example, 40%). When the determination is No, the routine is terminated as it is. When the determination is Yes, the routine proceeds to step S10 and the routine is terminated after executing the normal control mode (mode switching means).
As a result, basically, the normal control mode is selected when the battery 18 is low SOC, and the skip control mode is selected when the battery 18 is high SOC, but the hysteresis region is between the upper limit determination value SOCup and the lower limit determination value SOCdw. By functioning, frequent switching between both control modes is prevented.
Next, a description will be given while comparing the control status of the skip control mode executed based on the above routine with the control status of the normal control mode.

FIG. 4 is a time chart showing the shift state during vehicle acceleration in the normal control mode and the skip control mode, and FIG. 5 compares the engine operation region and the torque assist state of the electric motor 6 in each shift stage in the normal control mode and the skip control mode. FIG.
In the normal control mode, the transmission 8 is shifted based on the normal shift map shown in FIG. 2, and after the vehicle 1 starts at the second speed, which is the start speed, the speed of each shift speed increases as the vehicle speed V increases. Each time the shift-up line is crossed, switching to the gear position on the 1st gear speed side from the current gear position is sequentially performed. As a result, as indicated by a broken line in FIG. 4, the gear positions are continuously switched from the second speed to the third speed, the fourth speed, the fifth speed, and the sixth speed without jumping over any gear speed.
By the shift control of the transmission 8, the engine 2 is operated while increasing the rotation in each region shown in FIG. 5 for each shift stage in the process of accelerating the vehicle 1, and achieves the torque corresponding to the shift stage. To be controlled. For example, in the third speed, the engine is operated in a rotation range of 1300 to 2000 rpm, and a torque of 140 to 120 Nm is generated accordingly. Moreover, in 5th speed, it drive | operates in the rotation range of 1300-1700rpm, and generates a torque of 200-100Nm according to it.

The electric motor 6 that is operating the motor with respect to the control on the engine 2 side as described above is subjected to torque control so as to compensate for the shortage of the torque on the engine 2 side according to the torque distribution based on the required torque by the vehicle ECU 22. For example, in FIG. 5, a torque of 50 Nm is generated regardless of the rotational speed, thereby achieving the driver's required torque.
On the other hand, in the skip control mode, a shift is executed based on the skip shift map. As described above, in the skip shift map, the third speed region is set as the fourth speed region and the fifth speed region is set as the sixth speed region in the normal shift map. The speed is switched over by one step in order from the fourth speed to the fourth speed. That is, in the area where the third speed is selected in the normal control mode, the fourth speed on the first stage high speed gear side is selected, and similarly, in the area where the fifth speed is selected, the sixth speed on the first stage high speed gear side is selected. Is done.

By the shift control of the transmission 8, the engine 2 selects the fourth speed on the high-speed gear side in the region where the third speed is selected in the normal control mode in the process of accelerating the vehicle 1, as shown in FIG. So that it will be operated in the rotation range of 800-1300rpm. Further, in the region where the fifth speed is selected in the normal control mode, the sixth speed on the high-speed gear side is selected, so that the engine is operated in the rotation range of 800 to 1250 rpm.
FIG. 6 is a characteristic diagram showing characteristics of fuel consumption per hour (g / h) and operating efficiency (g / kw · h) of the engine 2 corresponding to FIG. 5. The shift of the engine 2 to the low speed side by selecting the fourth speed instead of the third speed and selecting the sixth speed instead of the fifth speed means that the fuel consumption of the engine 2 decreases. To do. Therefore, the fuel consumption of the engine 2 in the skip control mode is significantly reduced in the region where the third speed and the fifth speed should be selected in the normal control mode.

On the other hand, when the fourth speed and the sixth speed on the high-speed gear side are selected in the region corresponding to the third speed and the fifth speed in the normal control mode, the engine torque required to achieve the required torque increases. To do. Specifically, as shown in FIG. 5, a torque of 210 to 175 Nm is required at the fourth speed, and a torque of 290 to 140 Nm is required at the sixth speed. The control is executed with the same contents as in the normal control mode. As a result, at the fourth speed, an engine torque of 140 to 120 Nm similar to the third speed in the normal control mode is generated, and at the sixth speed, an engine torque of 200 to 100 Nm similar to the third speed of the normal control mode is generated.
In order to achieve the driver's required torque, the engine torque is insufficient. At this time, the driving torque of the electric motor 6 operating as a motor is compensated for by the vehicle ECU 22 based on the required torque. It is set on the increasing side (torque control means). For example, in FIG. 5, the torque of the electric motor 6 is increased from 50 Nm to 70 Nm, thereby achieving the driver's required torque.

  The above is the control situation during vehicle acceleration, but the same applies during vehicle deceleration. In the normal control mode, the speed of the transmission 8 is the sixth speed, fifth speed, fourth speed, third speed, In the skip control mode, the second speed is switched in order of the sixth speed, the fourth speed, and the second speed. Therefore, the sixth speed on the high gear side is selected in the region where the fifth speed is selected in the normal control mode, and the fourth speed is selected in the region where the third speed is selected in the normal control mode. Since the engine 2's rotational range shifts to the low speed side and the engine brake decreases, the regenerative torque of the motor 6 that is operating as a generator is increased to compensate for the decrease and achieve the desired braking force. Let The increase in regenerative torque leads to an increase in the amount of power generated by the electric motor 6, and the battery 18 is charged accordingly. Therefore, by using the charged electric power when the motor of the electric motor 6 is operated, the fuel consumption of the engine 2 can be reduced as a result.

As described above, in the present embodiment, when the SOC of the battery 18 is sufficient, the skip control mode is executed in which the shift speed of the transmission 8 is switched by one step and the third speed or the fifth speed is selected in the normal control mode. By selecting the fourth speed or the sixth speed in the region to be operated, the rotational range of the engine 2 is shifted to the low speed side at any time of acceleration or deceleration of the vehicle 1 to reduce the fuel consumption. . Further, by compensating for the shortage of engine torque caused by this by increasing the torque of the electric motor 6, the driver's required torque can be reliably achieved to prevent the driving feeling from deteriorating.
That is, unlike the technique of Patent Document 1 in which only the driving force distribution is optimized, the engine 2 side is more fuel-consumed on the condition that the torque on the electric motor 6 side has a surplus power based on the SOC of the battery 18. Since the engine 2 and the electric motor 6 can be operated more efficiently as a whole, the fuel efficiency can be improved as described above.

In addition, since the hardware configuration is the same as that of the conventional hybrid electric vehicle 1, it can be implemented simply by changing the control program of the vehicle ECU 22, and thus the above-described effects can be easily realized.
By the way, in the above embodiment, as a result of considering the fuel consumption characteristics of the engine 2 shown in FIG. 6, the engine 2 is shifted to the low rotation side at the fourth speed and the sixth speed in the skip control mode, and the engine control is performed. Executed with the same contents as in normal control mode. As a result, for example, at the 4th speed, the engine 2 is originally required to operate in the torque range of 210 to 175 Nm indicated by the solid line in the figure, but actually, the engine 2 is in the torque range indicated by the broken line on the lower torque side. The torque shortage is compensated by the torque of the electric motor 6. However, when the engine 2 is generating driving torque for vehicle acceleration, such a transition of the engine torque range may not be desirable in terms of the operating efficiency of the engine 2.

That is, as shown by the operating efficiency characteristics of the engine 2 shown in FIG. 6, the operating efficiency of the engine 2 tends to decrease as the region near the maximum torque curve is the best region and shifts to a lower torque side from the region. Naturally, although this characteristic varies depending on the specifications of the engine 2, the overall characteristic is as described above regardless of the engine specifications. For this reason, when the engine torque decreases from the high torque side to the low torque side in the engine torque range, and the engine torque decreases to a region where the decrease in operating efficiency is significant, the engine rotation is performed as described above. Despite shifting the region to the low rotation side, the fuel consumption of the engine 2 increases on the contrary.
Therefore, in an operation region where such a situation is predicted to occur, even if measures are taken to increase the engine torque slightly to suppress a decrease in operation efficiency and correct the torque of the motor 6 to the lower side by the amount of torque increase. Good (torque control means). By implementing such measures, fuel consumption that fluctuates mainly according to the engine speed range and driving efficiency that fluctuates mainly according to the engine torque range can be achieved at a high level, thereby further improving fuel efficiency. Can do.
This is the end of the description of the embodiment, but the aspect of the present invention is not limited to this embodiment. For example, in the above embodiment, the hybrid electric vehicle 1 is configured as a truck, but the type of vehicle is not limited to this, and may be embodied as, for example, a passenger car.

In the above-described embodiment, the transmission 8 that automates the connection / disconnection operation of the clutch 4 and the switching operation of the shift stage based on a general manual transmission is used. However, a so-called dual clutch transmission may be used. . The dual clutch transmission is disclosed in, for example, Japanese Patent Application Laid-Open No. 2009-035168, and thus will not be described in detail. However, the gear mechanisms divided into odd and even stages are respectively connected to the motor 6 side via clutches. When the power transmission is performed by connecting the clutch of one gear mechanism and transmitting the power, the clutch of the other gear mechanism is disconnected and switched to the next predicted gear stage in advance, and the shift timing is reached. The power transmission by the other gear mechanism is started by reversing the connection / disconnection state of both clutches. Also in such a dual clutch transmission, the same effect can be obtained by taking the measures described in the above embodiment.
Further, in the above embodiment, the vehicle travel mode is switched between the engine single travel, the motor single travel, and the engine / motor combined travel in accordance with the required torque, the SOC of the battery 18, etc., but is not limited thereto. For example, the present invention may be applied to a hybrid electric vehicle that executes only engine / electric motor combined driving.

In the above embodiment, the skip shift map characteristic is set so as to jump over the third speed and the fifth speed of the six forward speeds. However, the present invention is not limited to this. For example, the skip shift map characteristic may be set so as to jump over the second speed and the fourth speed, or when the transmission 8 has a larger number of shift stages, the skip shift map is set so as to jump over two stages or more. May be.
Further, in the above embodiment, for example, even if the skip control mode is started based on the SOC of the battery 18 in step S6 of FIG. 3 during vehicle acceleration at the second speed, the vehicle speed V increases and the fourth speed range ( Until the vehicle enters the third speed region in the normal shift map), the fuel consumption reduction effect by shifting the engine rotation region to the low rotation side cannot be obtained.
Therefore, for example, as shown in FIG. 7, in addition to the first skip shift map having the characteristic of jumping over the third speed and the fifth speed (specific shift stage) similar to the embodiment, the second speed and the fourth speed (specific shift) A second skip shift map having characteristics of jumping over the first step) is set in advance, and when the shift step at the time when the skip control mode is started is the third speed or the fifth speed, the first skip shift map is applied. The second skip shift map may be applied when the first gear stage is the second speed or the third speed. As a result, even if the skip control mode is started at any gear stage, the engine speed range is immediately shifted to the low speed side by jumping over that gear stage and selecting the gear stage on the high speed gear side. As a result, a fuel consumption reduction effect can be obtained with certainty even in a short time.

DESCRIPTION OF SYMBOLS 1 Engine 6 Electric motor 8 Transmission 16 Drive wheel 18 Battery 22 Vehicle ECU (normal transmission means, skip transmission means, remaining capacity detection means,
Mode switching means, torque control means)

Claims (3)

In a travel control device for a hybrid electric vehicle that travels by transmitting torque of an engine and an electric motor to drive wheels via a transmission having a plurality of shift stages,
Normal transmission means for successively and continuously switching each shift stage of the transmission according to the vehicle speed;
Skip transmission means for executing a skip shift for switching the shift stage so as to jump over a specific shift stage among the shift stages of the transmission according to the vehicle speed;
A remaining capacity detecting means for detecting a remaining capacity of a battery for supplying electric power to the electric motor;
When the remaining capacity of the battery detected by the remaining capacity detecting means is less than a preset judgment value, the normal control mode is selected and the transmission is shifted by the normal shifting means, and the remaining capacity of the battery is determined. Mode switching means for selecting a skip control mode and shifting the transmission by the skip transmission means when the determination value is equal to or greater than the determination value;
The driver's requested torque is distributed to the engine side and the motor side, and the torque of the engine and motor is controlled based on the torque distribution, while the skip control mode is selected by the mode switching means, and the skip transmission means is Torque control means for correcting the torque of the electric motor to the increase side to compensate for engine torque shortage due to the shift of the engine rotation range to the low rotation side when the skip shift is being performed. A traveling control device for a hybrid electric vehicle characterized by the above.   When the torque control means generates torque on the drive side as the vehicle accelerates, the engine torque is reduced to a region where the engine efficiency is significantly reduced as a result of the skip shift by the skip control means. 2. The travel control device for a hybrid electric vehicle according to claim 1, wherein, when it decreases, the engine torque is increased and the torque of the electric motor is corrected to the decrease side by the increase in torque. The skip shift means selectively executes a plurality of skip shifts set so as to jump over specific shift stages different from each other among the shift stages.
The mode switching means selects, from the plurality of skip shifts, a skip shift having the shift stage as the specific shift stage based on the shift stage of the transmission at the time when the skip control mode is selected. 3. The travel control apparatus for a hybrid electric vehicle according to claim 1, wherein a shift is executed by the skip transmission means.

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