JP5956714B2 - Control device for hybrid vehicle - Google Patents

Description

  The present invention relates to a control device for a hybrid vehicle suitable for use in a hybrid vehicle equipped with a so-called dual clutch transmission.

There is a so-called dual clutch transmission (hereinafter also referred to as DCT) as a transmission equipped in an automobile. In this DCT, a clutch and a transmission gear mechanism are divided into two systems, an odd-numbered system and an even-numbered system, and a gear can be instantaneously changed by switching two clutches.
The two clutches are coaxially disposed on the output axis of the engine, and a transmission input shaft is coupled to each clutch. Therefore, the two transmission input shafts are also arranged coaxially. For this reason, one transmission input shaft is configured as a hollow shaft, and this one hollow transmission input shaft is disposed on the outer periphery of the other transmission input shaft.

  In recent years, a hybrid electric vehicle (hereinafter also referred to as HEV) equipped with an internal combustion engine (hereinafter also referred to as an engine) and a motor generator (hereinafter also referred to as a motor) has been put into practical use as a travel drive source of the automobile. Yes. This hybrid vehicle is equipped with a battery in order to supply power when the motor is powered and to charge the generated power during regenerative braking of the motor. The power of the battery is consumed by the power running of the motor, and the battery is charged by the regenerative power of the motor.

And the technique which applied the above-mentioned DCT to a hybrid electric vehicle is also disclosed by patent documents 1-3 etc., for example.
The techniques disclosed in these Patent Documents 1 to 3 are all hybridized without changing the structure of the existing DCT as much as possible. For example, in the technique of Patent Document 1, two techniques are arranged on the same axis. A motor is disposed on one transmission input shaft disposed on the outer periphery of the transmission input shaft. In this case, a rotor may be installed on the outer periphery of one of the transmission input shafts, and a stator may be installed on the outer periphery of the rotor, and the existing DCT can be hybridized with little change.

  Thus, in the case of a system in which a motor is arranged on one transmission input shaft, the two clutches are both disconnected when the charging rate of the battery supplying power to the motor is high (hereinafter referred to as high SOC). Thus, by running the motor alone, the engine can be operated idling to improve fuel efficiency.

JP 2009-035168 A JP 2005-186931 A Japanese Patent Laying-Open No. 2005-147312

  By the way, in the hybrid electric vehicle using the above-described DCT, when the motor is operating with a high SOC and one and the other clutches are disconnected, the gear stage on the motor side (one transmission gear mechanism) is switched. In this case, since the torque of the transmission gear mechanism on the motor side is lost, in order to suppress this, when switching the gear stage on the motor side, the other clutch is engaged so that the engine torque can be used. Thus, control for preventing torque loss is performed.

  Since the engine is operated at the idling speed when the motor is traveling alone, when performing control to prevent this torque loss, the engine speed is changed from the idling speed to the traveling speed and the selected gear stage of the other transmission gear mechanism. The number of revolutions is temporarily increased according to the above, and then the other clutch is engaged. Then, when the switching of the gear side on the motor side is completed, the other clutch is disconnected, and the engine speed is lowered to enter the idling state.

Therefore, when shifting is performed when the motor is traveling alone, the rotational speed of the engine that is originally operating at the idle rotational speed temporarily increases temporarily. Such increase or decrease in the engine rotational speed is caused by the behavior of the vehicle and the engine rotational speed. Does not match, and there is a problem of making the driver feel uncomfortable.
Also, when the motor is running alone with one and the other clutch disconnected with high SOC, if the motor torque alone cannot satisfy the driver's required torque, it is necessary to compensate for the insufficient torque with the engine. Become. For this purpose, either of the two clutches that were released when the motor alone traveled was engaged, and a time lag occurred in the torque increase for the time required to engage the clutch, and the driver felt uncomfortable. give.

  Furthermore, in order to run the motor alone, it may be necessary to use the motor with a high torque or rotational speed. In this case, extra power is consumed and sufficient battery SOC is secured when motor assist is required. There is a risk that it cannot be done. For this reason, it is expected that switching between the motor single traveling and the combined driving of the motor and the engine is required relatively frequently, and the driver feels uncomfortable each time.

  The present invention has been devised in view of such a problem, and in a hybrid electric vehicle in which a motor is attached only to one transmission input shaft of a dual clutch transmission, the clutch is connected and disconnected at the time of shifting gears and the like. It is an object of the present invention to provide a control device for a hybrid electric vehicle that can eliminate a sense of incongruity given to a driver and can use a battery efficiently.

  In order to achieve the above object, a control device for a hybrid electric vehicle according to the present invention receives an output torque of an engine, a motor, and / or the engine and the motor, and transmits the output torque to a drive wheel. A control device for a hybrid electric vehicle comprising: a first input shaft that is connected to the engine via a first clutch and in which the motor is disposed; A first speed change mechanism having a stage; and a second speed change mechanism having a second input shaft connected to the engine via a second clutch and having a plurality of speed stages, and detecting a driver acceleration request When the acceleration request detection means and the acceleration request detection means detect the driver's acceleration request, the first and second clutches are simultaneously used except when the start gear stage of the first transmission mechanism is used. It is characterized in that a clutch control means for inhibiting disconnection.

In the control apparatus for a hybrid electric vehicle, the clutch control means permits simultaneous disengagement of the first and second clutches when the start gear stage of the first transmission mechanism is used.
The control apparatus for a hybrid electric vehicle further includes battery charge amount detection means for detecting a charge amount of a battery charged and discharged by the motor, wherein the clutch control means is detected by the battery charge amount detection means. When the battery charge amount is equal to or greater than a predetermined charge amount and the start shift stage of the first transmission mechanism is used, simultaneous disconnection of the first and second clutches is permitted.

  According to the control apparatus for a hybrid electric vehicle of the present invention, the clutch control means detects the acceleration request of the driver by the acceleration request detection means except when the start gear stage of the first transmission mechanism is used (high gear stage use). In order to prohibit simultaneous disconnection of the first and second clutches, the engine speed is determined according to the running speed and the selected gear stage via the first or second clutch except when starting. Therefore, the engine speed matches the vehicle behavior, and the driver does not feel uncomfortable.

In addition, since the engine output torque is transmitted to the drive wheels via the first or second clutch at times other than when starting, the time lag required for clutch engagement is eliminated, and the driver's acceleration request is promptly met. Can respond.
In addition, since the simultaneous disconnection of the first and second clutches is prohibited except at the time of starting, the motor alone is prohibited from running, and the maximum torque or the maximum number of revolutions required for the motor can be suppressed. Consumption can be suppressed. It is possible to secure the SOC of the battery during assist running by the motor.

In addition, by prohibiting motor single travel except when starting, it is not necessary to frequently switch between motor single travel and combined use of the motor and engine, so that the engine speed matches the vehicle behavior, and the driver The discomfort given to can be eliminated.
In addition, if simultaneous disengagement of the first and second clutches is permitted when the start gear stage of the first speed change mechanism is used, it is possible to start with the output of the motor alone, which contributes to improved fuel consumption.

  If the battery charge amount detected by the battery charge amount detection means is larger than the predetermined charge amount, and the simultaneous disengagement of the first and second clutches is permitted when the start gear stage of the first transmission mechanism is used, the battery It is possible to start with the output of the motor alone while securing the amount of charge, which contributes to improved fuel efficiency.

1 is a diagram schematically showing an overall configuration of a control apparatus for a hybrid vehicle according to an embodiment of the present invention. It is a figure which shows typically the power transmission of the control apparatus of the hybrid vehicle concerning one Embodiment of this invention, (a) is a figure which shows the power transmission at the time of motor independent driving | running | working, (b) is 1st and 1st It is a figure which shows the power transmission at the time of combined driving | running | working of a motor and an engine via a 2 speed-change gear mechanism, (c) is a figure which shows the power transmission at the time of driving | running | working combined use of a motor and an engine only through a 1st transmission gear mechanism. is there. It is a flowchart which shows control of the hybrid vehicle concerning one Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[One Embodiment]
1 to 3 illustrate a control apparatus for a hybrid electric vehicle according to an embodiment of the present invention. FIG. 1 is a diagram showing the overall configuration, and FIGS. 2 (a) to 2 (c) are power transmissions thereof. FIG. 3 is a flowchart showing the control.

[Configuration of power system]
First, a configuration of a power system of a hybrid electric vehicle to which the control device according to the present embodiment is applied will be described.
The hybrid electric vehicle according to the present embodiment is a commercial vehicle such as a truck or a bus, for example, and is a large vehicle or a medium-sized vehicle having a larger vehicle body than a passenger vehicle, and is equipped with a diesel engine.

  As shown in FIG. 1, the vehicle (here, the front of the vehicle) includes an engine (internal combustion engine) 1, a clutch unit 2, a motor (motor generator) 3, and a transmission gear mechanism (transmission) 4 as a drive system. Further, the transmission gear mechanism 4 is connected to the rear wheels 8 and 8 as drive wheels via a propeller shaft 5, a rear differential (rear differential) 6 and drive shafts 7 and 7 so as to be able to transmit power. . The front wheels 9, 9 are driven wheels.

In the present embodiment, a so-called dual clutch transmission (hereinafter also referred to as DCT) is used for the transmission gear mechanism 4. In this DCT, a clutch and a transmission gear mechanism are divided into two systems of an odd number and an even number, and gears can be changed in a very short time (only clutch change time) by changing two clutches. it can.
That is, in the clutch unit 2, the first clutch 2A and the second clutch 2B are arranged side by side on the same axis. The first clutch 2A and the second clutch 2B are connected and disconnected independently by a clutch actuator (not shown).

In addition, the transmission gear mechanism 4 includes a first transmission gear mechanism (first transmission mechanism) 4A equipped with a gear pair of even speed stages of 2nd speed, 4th speed, and 6th speed, and 1st speed, 3rd speed, 5th speed. A second transmission gear mechanism (second transmission mechanism) 4B equipped with a gear pair of an odd-numbered speed stage is arranged side by side on the same axis.
Each input side of the first clutch 2A and the second clutch 2B is connected to the output shaft 1A of the engine 1, and the output side of the first clutch 2A is connected to the input shaft (first input shaft) 40A of the first transmission gear mechanism 4A. The output side of the second clutch 2B is connected to an input shaft (second input shaft) 40B of the second transmission gear mechanism 4B.

  The first input shaft 40A is a hollow shaft and is coaxially disposed on the outer periphery of the second input shaft 40B. The first input shaft 40A is rotatably equipped with a second speed drive gear 42a, a fourth speed drive gear 44a, and a sixth speed drive gear 46a, and a portion of the second input shaft 40B protruding from the end of the first input shaft 40A. The first-speed drive gear 41a, the third-speed drive gear 43a, and the fifth-speed drive gear 45a are rotatably mounted.

  The motor 3 is mounted on the outer periphery of the first input shaft 40A between the clutch unit 2 and the first and second transmission gear mechanisms 4A and 4B. That is, the rotor (rotor) 3A of the motor 3 is fixed to the outer periphery of the first input shaft 40A, and the stator (stator) 3B is supported on the outer periphery of the rotor 3A by a transmission casing (not shown). Is arranged opposite to the rotor 3A, receives power supply during power running to rotate the rotor 3A, generates power by rotation on the rotor 3A side during regeneration, and applies braking force on the rotor 3A side according to the power generation load. Is granted.

  Further, a counter shaft 40C is disposed in parallel with the input shafts 40A and 40B, next to the first input shaft 40A and the second input shaft 40B. The counter shaft 40C is fixedly provided with a second speed driven gear 42b, a fourth speed driven gear 44b, a sixth speed driven gear 46b, a first speed driven gear 41b, a third speed driven gear 43b, and a fifth speed driven gear 45b. It meshes with the stage drive gear. The counter shaft 40C is connected to the propeller shaft 5 via a gear pair 48, and the counter shaft 40C is interlocked with the propeller shaft 5.

  As described above, each of the drive gears 41a to 46a is rotatably supported by the input shaft 40A or 40B. However, the drive gears 41a to 46a rotate integrally with the input shafts 40A and 40B through the synchronization devices 47a to 47d, respectively. It has become. The second speed drive gear 42a will be described as an example. The synchronizer 47a includes a sleeve 47sl that is integrally rotated with the input shaft 40A and is slidable in the axial direction, and an actuator (not shown) that slides the sleeve 47sl. When the sleeve 47sl slides and engages with the clutch gear 47cg, the drive gear to which the engaged clutch gear 47cg is fixed is connected to the corresponding input shaft 40A. Rotates together.

  Therefore, for example, when achieving the second speed, if the corresponding sleeve 47sl is slid and engaged with the clutch gear 47cg of the second speed drive gear 42a, the second speed drive gear 42a rotates integrally with the input shaft 40A. At this time, if the first clutch 2A is connected, the engine 1, the first clutch 2A, the first input shaft 40A, the second speed drive gear 42a, the second speed driven gear 42b, the counter shaft 40C, the gear pair 48, a propeller shaft 5, a rear differential 6, drive shafts 7 and 7, and drive wheels 8 and 8 are formed, and the rotation of the engine 1 is shifted at a gear ratio corresponding to the second gear to drive wheels 8 and 8 8 is transmitted.

Similarly, the fourth speed and the sixth speed can also be achieved by engaging the sleeve 47sl corresponding to each clutch gear 47cg and connecting the first clutch 2A.
Similarly, the first, third and fifth speeds can be achieved by engaging the sleeves 47sl corresponding to the clutch gears 47cg and connecting the second clutch 2B.
Therefore, for example, in order to shift up from the 2nd speed to the 3rd speed, the corresponding sleeve 47sl is engaged with the clutch gear 47cg of the 2nd speed drive gear 42a, and the 2nd speed traveling state in which the first clutch 2A is connected. Then, with the second clutch 2B disconnected, the corresponding sleeve 47sl is engaged with the clutch gear 47cg of the third-speed drive gear 43a. Thereafter, when the engine 1 alone travels, so-called clutch switching is performed in which the second clutch 2B is connected while the first clutch 2A is disconnected. Since the clutch gear 47cg and the sleeve 47sl of the shift destination gear stage (in this case, the third speed stage) can be pre-engaged during the second speed travel, the speed change operation affecting the torque transmission is Only the clutch is changed, and a substantially quick shift (shifting of the gear stage) can be performed.

  In the case of this drive system, since the motor 3 is mounted on the first input shaft 40A, the motor 3 can transmit power even if both the first clutch 2A and the second clutch 2B are disconnected. , 2B can be cut off, and driving with a driving torque by the motor 3 alone or regenerative braking main braking can be realized without using engine braking. Further, it is also possible to travel together with the motor 3 and the engine 1 by connecting at least one of the clutches 2A and 2B.

  The motor 3 is connected to the inverter 31, and the inverter 31 is connected to the battery 32. The operation of the motor 3 is controlled by the control of the power transfer of the battery 32 by the inverter 31. The inverter 31 supplies power to the motor 3 from a battery (for example, a battery group in which a plurality of chargeable / dischargeable secondary cells (cells) such as lithium ion batteries are connected in series) during powering and outputs the power. The motor 3 functions as an electric motor that generates torque, and at the time of regenerative braking, the motor 3 functions as a generator that generates electric power (regenerative power generation) using kinetic energy of the vehicle, and the electric power generated by the regenerative power generation is used for charging the battery 32.

[Control system configuration]
The engine 1, the first clutch 2A, the second clutch 2B, the motor 3, and the transmission gear mechanism 4 are controlled or managed by electronic control using a computer.
An engine ECU 61 is provided for controlling the engine 1, an inverter ECU 62 is provided for controlling the inverter 31 that operates the motor 3, and a battery ECU 63 is provided for managing the battery 32. A vehicle ECU 60 is provided to integrally control the engine ECU 61, the inverter ECU 62, and the battery ECU 63 and to control the clutches 2A and 2B and the transmission gear mechanism 4. The vehicle ECU 60 is provided with a clutch control means 60a described later as software.

  Since the battery 32 is deteriorated due to excessive charging / discharging, the amount of charge is managed within a battery usage band which is a fixed band. The battery usage band is defined as a region sandwiched between a preset upper limit value for limiting further charging and a lower limit value for limiting further discharging. The vehicle ECU 60 controls the power running or regeneration of the motor 3 via the inverter ECU 62 so that the charge amount of the battery 32 detected by the battery ECU 63 falls within the battery usage band.

  The battery ECU 63 includes a battery current sensor 51 that detects a charge / discharge current of the battery 32, a battery voltage sensor 52 that detects a charge / discharge voltage of the battery 32, and a battery charge / discharge counter that detects the number of times of charge / discharge of the battery 32. 54, the amount of charge of the battery 32 is calculated by the battery ECU 63 based on the current and voltage when the battery 32 is charged and discharged. These sensors 51 and 52 and the counter 54 are connected to each cell of the battery 32, and may detect the current, voltage, and number of charge / discharge of each cell, or one sensor for several cells. May be connected to detect the current, voltage, and the number of charge / discharge of these several cells, or a combination of connecting one sensor to each of these cells or to some cells may be combined as appropriate. Each sensor may be provided.

Each of these ECUs 60, 61, 62, and 63 is a computer comprising a CPU, ROM, RAM, input / output circuit, and the like, and appropriate devices are attached or connected thereto.
The vehicle ECU 60 connects the engine ECU 61, the inverter ECU 62, and the battery ECU 63 in a controllable manner, controls the engine 1 via the engine ECU 61, and the electric power of the motor 3 and the battery 32 connected to the inverter 31 via the inverter ECU 62. The charge amount of the battery 32 calculated by the battery ECU 63 is input.

  The vehicle ECU 60 is connected to receive a detection signal of an accelerator position sensor (acceleration request detecting means) 58. The accelerator position sensor 58 detects the accelerator opening, and detects the presence or absence of a driver's acceleration request. The presence / absence of the acceleration request may be determined, for example, by the presence / absence of the accelerator opening, or may be determined to be an acceleration request when the accelerator opening is equal to or greater than a certain value. If it is increased, it may be determined that an acceleration request is made.

  The vehicle ECU 60 includes a vehicle running state (for example, vehicle speed), a selection stage of the transmission gear mechanism 4 (selected transmission stage), a state of driving or braking command to the vehicle (for example, an accelerator opening degree and a brake operation amount), a battery ECU 63. Based on the charge amount of the battery 32 calculated by the above, the engine 1, the first clutch 2A, the second clutch 2B, the motor 3, the first transmission gear mechanism 4A and the second transmission mechanism 4B are managed and controlled. The selection stage is a gear stage in which each of the transmission gear mechanisms 4A and 4B is engaged. In other words, the gear positions of the drive gears 42a, 44a and 46a engaged by the first transmission gear mechanism 4A and the gear stages of the drive gears 41a, 43a and 45a engaged by the second transmission gear mechanism 4B, respectively.

  When driving, the vehicle ECU 60 sets a driving torque necessary for the vehicle based on the accelerator opening, sets which one of the engine 1 and the motor 3 is used, or both of them. When both the motor 3 and the motor 3 are used, the drive torque is distributed. The engine ECU 61 and the inverter ECU 62 control the operation of one or both of the engine 1 and the motor 3 so as to output the driving torque set by the vehicle ECU 60.

The clutch control means 60a of the vehicle ECU 60 controls the disengagement and engagement of the first clutch 2A and the second clutch 2B which are performed together with the operation control of the engine 1 and the motor 3.
That is, the vehicle ECU 60 sets the torque required for the vehicle and determines the use of one or both of the engine 1 and the motor 3 as a drive source according to the selection stage of the transmission gear mechanisms 4A and 4B.

  When an acceleration request is detected by the accelerator position sensor 58, the clutch control means 60a has a charge amount of the battery 32 calculated by the battery ECU 63 equal to or greater than a predetermined charge amount, and the first shift gear mechanism 4A of the transmission gear mechanism 4 When the use stage (shift stage in use) is the start stage (start shift stage), both the clutches 2A and 2B are disconnected, and the vehicle starts using the drive torque of the motor 3 alone. That is, when the charge amount of the battery 32 is equal to or greater than the predetermined charge amount and the use stage of the first transmission gear mechanism 4A to which the drive torque of the motor 3 is input is a preset start stage, the clutch 2A, Allow simultaneous block of 2B. The use stage is a shift stage used for transmission of drive torque by the drive sources 1 and 3 during traveling including starting. In other words, each of the transmission gear mechanisms 4A and 4B selects one of the gears, and the gear used for transmitting the driving torque at the selected gear is the used gear.

  Here, the predetermined charge amount of the battery 32 is a charge amount determined experimentally and empirically in advance as the charge amount in the battery use band, and even if the vehicle is started by the motor 3 and consumes electric power. The charging amount with a margin with respect to the aforementioned lower limit value is set. Thereby, the opportunity to start by the single power running of the motor 3 at the time of start can be ensured. For example, the predetermined charge amount is appropriately set as an intermediate charge amount between the above-described upper limit value and the above-described lower limit value.

  The engine 1 is started together with the motor 3 or after the motor 3 is started. When the motor 3 is traveling alone, the engine 1 is operated at the idle speed. After the start, when the vehicle is traveling with the gears switched and shifted up, the clutch control means 60a raises the engine 1 from the idling speed to the speed corresponding to the running speed and the selected speed of the transmission gear mechanisms 4A and 4B. Either the clutch 2A or 2B is connected, and the engine 1 and the motor 3 are used in combination, or the engine 1 runs alone. That is, the clutch control means 60a prohibits simultaneous disconnection of the clutches 2A and 2B when the use stage of the first transmission gear mechanism 4A is other than the start stage.

  The starting stage of the transmission gear mechanism 4 is set as the smallest transmission stage of the first transmission gear mechanism 4A equipped with the motor 3. Here, the first transmission gear mechanism 4A has second, fourth, and sixth speeds, and the second speed, which is the smallest of these speeds, is set as the start speed. Yes. The automobile according to the present embodiment is a medium-sized or large-sized commercial vehicle, and is generally set in such a manner that the second speed start is performed. For example, the first transmission gear mechanism 4A equipped with the motor 3 has The first speed, the third speed, and the fifth speed may be adopted. In this case, the first speed or the third speed is set as the starting speed depending on the driver request torque and the vehicle weight.

  For example, at the time of start when acceleration is requested by the driver, if the battery charge amount is equal to or greater than a predetermined charge amount and the selected speed of the transmission gear mechanism 4 is the start speed (second speed here), the clutch control means 60a The motor 3 is controlled to be able to travel alone by simultaneously shutting off 2A and 2B. In this case, as shown in FIG. 2A, the clutches 2A and 2B are simultaneously cut off, the engine 1 is operated at the idling speed, and only the torque due to the power running of the motor 3 is applied to the first transmission gear mechanism 4A. Through the transmission gear (2nd gear) and is transmitted to the drive wheels. In this case, the selection stage of the second transmission gear mechanism 4B is the third speed stage.

  Thereafter, when the third gear is selected as the gear position of the transmission gear mechanism 4, the vehicle ECU 60 determines whether the output torque equivalent to the third gear from the engine 1 can be output by the second gear and the motor 3. to decide. If it is determined that output is possible, the clutch control means 60a continues to shut off the clutches 2A and 2B at the same time, and continues the single-running of the second-speed motor 3 with the output torque equivalent to the third-speed output by the engine 1. Control to do. When the vehicle ECU 60 determines that the output torque corresponding to the third speed of the engine 1 cannot be output by the second speed and the motor 3, the clutch control means 60a detects the engine 1 from the idle speed and the traveling speed and The second clutch 2B is connected by increasing the rotational speed according to the selected gear position (third gear) of the second speed change mechanism 4B. Then, the engine 1 and the motor 3 are used in combination or the engine 1 is used alone. As shown in FIG. 2 (b), the power transmission of the combined traveling of the engine 1 and the motor 3 is to power-run the motor 3 with the second clutch 2B connected while maintaining the disengaged state of the first clutch 2A. As a result, the output torque of the engine 1 is transmitted to the drive wheels via the third speed, which is the speed of the second speed change mechanism 4B, and the motor is transmitted via the second speed, which is the speed of the first speed change gear mechanism 4A. Torque due to the power running of 3 is also transmitted to the drive wheels. That is, the engine 1 and the motor 3 are used together.

In addition, in order to transmit the power of the single running by the engine 1 when the use stage is an odd stage such as the third speed stage, the second clutch 2B is connected while maintaining the disengaged state of the first clutch 2A. 3 is in an unloaded state. As a result, only the output torque of the engine 1 is transmitted to the drive wheels via an odd-numbered gear such as the third gear that is the gear position of the second transmission mechanism 4B.
Further, for example, the combined running state of the engine 1 and the motor 3 in which the driving torque of the motor 3 is via the second gear of the first transmission gear mechanism 4A and the driving torque of the engine 1 is through the third gear of the second transmission gear mechanism 4B. Is switched to the fourth speed of the first transmission gear mechanism 4A and the driving torque of the engine 1 is output, the clutch control means 60a drives the engine 1 and the selected transmission speed (third speed) of the second transmission mechanism 4B. The second clutch 2B is disconnected and the first clutch 2A is connected by connecting the first clutch 2A by controlling the number of rotations according to the traveling speed and the number of revolutions according to the selected gear stage (fourth speed stage) of the first transmission gear mechanism 4A. Change, run with the engine 1 and the motor 3 in combination or with the engine 1 alone. As shown in FIG. 2 (c), the power transmission in the case of combined use of the engine 1 and the motor 3 is connected only to the first clutch 2A, and the output torque of the engine 1 is selected via the first transmission gear mechanism 4A. The speed is changed according to the gear ratio of the gear and transmitted to the drive wheels, and torque generated by the power running of the motor 3 is also transmitted to the drive wheels via the first transmission gear mechanism 4A. That is, when the vehicle travels only through the first transmission gear mechanism 4A equipped with the motor 3 using a gear other than the starting gear, the single travel of the motor 3 is prohibited.

  Further, for example, when switching from the second gear of the first transmission mechanism 4A to the fourth gear of the first transmission gear mechanism 4A, the switching of the gear from the second gear to the third gear and the third gear are performed. The speed change to the 4th speed is performed continuously and quickly. The power transmission after this shift is connected to only the first clutch 2A, as in the case of switching from the third speed of the second transmission mechanism 4B to the fourth speed of the first transmission gear mechanism 4A. It runs with the combined use or the engine 1 alone. As shown in FIG. 2 (c), the power transmission in the case of combined use of the engine 1 and the motor 3 is connected only to the first clutch 2A, and the output torque of the engine 1 is selected via the first transmission gear mechanism 4A. The speed is changed according to the gear ratio of the gear and transmitted to the drive wheels, and torque generated by the power running of the motor 3 is also transmitted to the drive wheels via the first transmission gear mechanism 4A. That is, even when the vehicle travels only through the first transmission gear mechanism 4A equipped with the motor 3, the single travel of the motor 3 is prohibited.

  In addition, in order to perform power transmission of the single travel by the engine 1 when the use stage is an even stage such as the fourth speed stage, as shown in FIG. 2C, the first clutch 2B is disengaged as shown in FIG. The clutch 2A is connected and the motor 3 is in a no-load state. As a result, only the output torque of the engine 1 is transmitted to the drive wheels via the gears of any of the first transmission gear mechanisms 4A.

  In other words, the clutch control means 60a determines that the battery charge amount is a predetermined charge amount, and if the selected speed is the second speed and the third speed, the second speed that the selected speed of the first transmission gear mechanism 4A is the start speed. Therefore, it is permitted to travel with both clutches 2A and 2B disconnected. Thereafter, the gear position of the first transmission gear mechanism 4A is always switched from the second speed stage to the fourth speed stage before shifting the use stage to the fourth speed stage. However, the gear stage of the first transmission gear mechanism 4A is changed to the fourth speed stage. At the time of switching, single motor traveling is prohibited and the first clutch 2A is connected.

In addition, regarding the shift from the second speed to the fourth speed of the first transmission gear mechanism 4A, the motor 3 is in a no-load state and the first transmission gear mechanism 4A is shifted so that no load is applied. At the time of this speed change, the first clutch 2A is disconnected, the second clutch 2B is connected, and power transmission is performed only by the engine 1.
That is, when the selected stage is the second speed stage and the third speed stage, the motor single travel is permitted, and when the selected stage is the third speed stage and the fourth speed stage, the motor single travel is prohibited.

Further, the clutch control means 60a prohibits simultaneous disconnection of the clutches 2A and 2B after the engine 1 and the motor 3 are used together.
That is, when the motor 3 is prohibited from traveling alone, the engine 1 and the motor 3 are used together, or the motor 3 is brought into a no-load state and is driven only by the engine 1.
Further, the clutch control means 60a may use only the condition that the first transmission gear mechanism 4A of the transmission gear mechanism 4 is in a state other than the starting stage as a condition for prohibiting simultaneous disconnection of the clutches 2A and 2B. That is, the clutch control means 60a may be configured to permit simultaneous disconnection of the clutches 2A and 2B when the use stage of the first transmission gear mechanism 4A is the start stage. However, according to this configuration, the clutch control unit 60a prohibits or permits simultaneous disconnection of the clutches 2A and 2B without determining whether the charge amount of the battery 32 is equal to or greater than the predetermined charge amount. The amount of charge is separately managed by the vehicle ECU 60 so as to fall between the above-described upper limit value and lower limit value.

  According to this configuration, the clutch control means 60a prohibits simultaneous disconnection of the clutches 2A and 2B when the first transmission gear mechanism 4A is used at a speed other than the starting speed, as shown in FIGS. 2 (b) and 2 (c). The combined running by the engine 1 and the motor 3 as shown is performed. Further, if the use stage of the first transmission gear mechanism 4A is the start stage, simultaneous disconnection of the clutches 2A and 2B is permitted, and the single running by the motor 3 as shown in FIG.

  The clutch control means 60a disconnects both the clutches 2A and 2B during braking. Thereby, the rotational energy of the drive wheel 8 is transmitted to the motor 2 and regenerative power generation is performed to charge the battery 32. Of course, if the regenerative braking does not satisfy the required braking force, the vehicle ECU 60 appropriately activates the engine brake or activates a mechanical braking mechanism provided on each wheel.

[Action / Effect]
Since the control apparatus for a hybrid electric vehicle according to an embodiment of the present invention is configured as described above, for example, the control shown in FIG. 3 is performed by the clutch control means 60a of the vehicle ECU 60. This control flow is performed periodically, for example, every several tens of ms.
First, a detection signal from the accelerator position sensor 58, information on the amount of charge of the battery 32 by the battery ECU 63, and information on the use stage of the transmission gear mechanism 4 are obtained (step S10).

Next, it is determined whether an acceleration request is made based on the accelerator opening detected by the accelerator position sensor 58 (step S20).
If it determines with the acceleration request | requirement being made, it will be determined whether the charge amount of the battery 32 is larger than predetermined charge amount (step S30).
Step S30 may be omitted. That is, if it is determined that an acceleration request is made, a determination in step S40 described later may be performed.

If it is determined that the charge amount of the battery 32 is greater than the predetermined charge amount, it is determined whether or not the selection stage of the first transmission gear mechanism 4A is the start stage (step S40). The starting speed is preset as, for example, the second speed stage of the first transmission gear mechanism 4A that is a transmission mechanism on the motor side.
If it is determined that the selection stage of the first transmission gear mechanism 4A is the start stage, simultaneous disconnection of the clutches 2A and 2B is permitted (step S50). Thereby, the single travel of the motor 3 is permitted.

Then, the control flow ends (return).
If it is determined in step S20 that no acceleration request has been made, the control flow ends (return).
On the other hand, if it is determined in step S30 that the charge amount of the battery 32 is equal to or less than the predetermined charge amount, or if it is determined in step S40 that the selection stage of the first transmission gear mechanism 4A is not the start stage, the clutch 2A , 2B are prohibited (step S100). Thereby, the single traveling of the motor 3 is prohibited.

  Accordingly, when the acceleration position sensor 58 detects the driver's acceleration request, the clutch control means 60a prohibits simultaneous disconnection of the clutches 2A and 2B except when the first shift gear mechanism 4A is in use. Since the speed of the engine 1 becomes the speed according to the travel speed and the selected gear stage via the first clutch 2A or the second clutch 2B except when starting and after traveling together with the engine, the engine speed and the vehicle The behavior matches and does not give the driver a sense of incongruity.

Since the output torque of the engine 1 is transmitted to the drive wheels 8 via the clutches 2A and 2B except when starting and after running together with the engine, the time lag required for engaging the clutches 2A and 2B is eliminated, and the driver Can quickly respond to the acceleration request.
Further, since the simultaneous disconnection of the clutches 2A and 2B is prohibited except when starting, the motor 3 is prohibited from traveling alone, and the maximum torque and the maximum number of revolutions required for the motor 3 can be suppressed, and the battery The consumption of 32 can be suppressed. The SOC of the battery 32 during assisting traveling by the motor 3 can be ensured.

Further, by prohibiting the single travel of the motor 3 other than at the time of starting, switching between the single travel of the motor 3 and the combined travel of the motor 3 and the engine 1 does not occur frequently, and the engine speed and the vehicle behavior are not changed. And the discomfort given to the driver can be eliminated.
Further, even when the start gear of the first transmission gear mechanism 4A is in use, if the charge amount of the battery 32 detected by the battery ECU 63 is smaller than the predetermined charge amount, simultaneous disconnection of the clutches 2A and 2B is prohibited. For example, the single traveling of the motor 3 with a predetermined charge amount or less can be prohibited, and the charge amount of the battery 32 can be secured.

In addition, if simultaneous disengagement of the clutches 2A and 2B is permitted when using the starting stage of the first transmission gear mechanism 4A, it is possible to start with the output of the motor 3 alone, which contributes to improved fuel consumption.
Further, if the battery charge amount detected by the battery ECU 33 is larger than the predetermined charge amount and the simultaneous disconnection of the clutches 2A and 2B is permitted when the first transmission gear mechanism 4A is used at the start stage, the charge amount of the battery 32 Can be started by the output of the motor 3 alone, which contributes to the improvement of fuel consumption.

  Since the clutch control means 60a prohibits simultaneous disconnection of the clutches 2A and 2B after the combined use of the engine 1 and the motor 3, frequent switching between the single drive of the motor 3 and the combined use of the motor 3 and the engine 1 is performed. Therefore, the engine speed and the behavior of the vehicle coincide with each other, and the uncomfortable feeling given to the driver can be eliminated.

[Others]
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  In the above-described embodiment, the engine 1, the inverter 31, and the battery 32 are directly controlled by the ECUs 61, 62, and 63, and the vehicle ECU 60 performs integrated control of the ECUs 61, 62, and 63. Instead, the vehicle ECU may control the engine 1, the inverter 31, and the battery 32 directly.

  The hybrid electric vehicle equipped with the dual clutch transmission of the present invention can be applied not only to a large commercial vehicle, but also to a normal vehicle as compared to a passenger car such as a truck or a bus, and also to a gasoline engine that is not a diesel engine.

1 Engine 1A Output shaft 2 Clutch unit 2A First clutch 2B Second clutch 3 Motor (motor generator)
3A rotor (rotor)
3B Stator
4 transmission gear mechanism 4A first transmission gear mechanism (first transmission mechanism)
4B Second transmission gear mechanism (second transmission mechanism)
5 Propeller shaft 6 Rear differential 7 Drive shaft 8 Rear wheel 9 Front wheel 31 Inverter 32 Battery 40A First input shaft 40B Second input shaft 40C Counter shaft 42a Second speed drive gear 42b Second speed driven gear 47a Synchronizer 47cg Clutch gear 47sl Sleeve 48 Gear pair 51 Battery current sensor 52 Battery voltage sensor 54 Battery charge / discharge counter 58 Accelerator position sensor (acceleration request detection means)
60 Vehicle ECU
60a Clutch control means 61 Engine ECU
62 Inverter ECU
63 battery ECU (battery charge detection means)

Claims (3)

A control apparatus for a hybrid electric vehicle comprising: an engine; a motor; and a transmission that receives an output torque of any one or both of the engine and the motor and transmits the torque to drive wheels.
The transmission is
A first speed change mechanism including a first input shaft connected to the engine via a first clutch and having the motor disposed thereon, and having a plurality of speed stages;
A second speed change mechanism including a second input shaft connected to the engine via a second clutch, and having a plurality of speed stages,
Acceleration request detection means for detecting a driver's acceleration request;
Clutch control means for prohibiting simultaneous disconnection of the first and second clutches when the acceleration request detection means detects a driver acceleration request, except when the start gear stage of the first transmission mechanism is used. A control apparatus for a hybrid electric vehicle characterized by comprising: The clutch control means includes
2. The control device for a hybrid electric vehicle according to claim 1, wherein simultaneous disconnection of the first and second clutches is permitted when the start gear stage of the first transmission mechanism is used. 3. Battery charge amount detecting means for detecting the charge amount of the battery charged and discharged by the motor;
The clutch control means includes
The simultaneous disconnection of the first and second clutches is permitted when the battery charge amount detected by the battery charge amount detection means is equal to or greater than a predetermined charge amount and the start gear stage of the first transmission mechanism is used. The control apparatus for a hybrid electric vehicle according to claim 1.

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