JP2008055997A - Control device of hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow a driver to sufficiently feel acceleration while improving fuel consumption. <P>SOLUTION: While driving wheels 3R and 3L are driven by a motor 1, an electric power is fed to the motor 1 from at least a generator 11 driven by an engine 10 or batteries 13. The output of the engine 10 is controlled to have an engine torque and an engine rotation speed under a highly efficient control line L with the fuel consumption enhanced regularly. At a rapid acceleration when an accelerator is largely stepped on, the output control of the engine 10 is changed to a driving state under an acceleration control line X1 (X2) where an increase degree of the engine rotation speed is larger than a case under the highly efficient control line L, for example, by reducing a power generation load of the generator 11. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a control device for a hybrid vehicle.

In the hybrid vehicle, in addition to the engine, a travel motor for driving the drive wheels is provided. The driving wheels can be driven by both the engine and the driving motor, and the driving wheel can be driven only by the driving motor, and the driving wheel can be driven only by the driving motor. . In such a hybrid vehicle, the output of the engine is controlled so as to improve the fuel consumption, and the insufficient output that is insufficient only by the engine output is compensated by supplying power from the battery to the motor. Patent Document 1 proposes controlling the engine output so that the engine torque and the engine speed are based on a high-efficiency control line set to be highly efficient.
JP 2001-227376 A

  As described above, controlling the engine output based on the high-efficiency control line is preferable in terms of improving fuel efficiency, but the driver feels uncomfortable during acceleration or does not have a refreshing acceleration feeling. It turned out to be easy to occur. In other words, the engine speed is increased at the time of acceleration, and the driver feels acceleration according to the degree of increase in the engine speed, but if the engine speed is changed based on the high efficiency control line, Since the rate of increase in engine speed was slow, the driver could not feel a sufficient acceleration feeling.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a control device for a hybrid vehicle in which acceleration can be fully experienced while improving fuel efficiency.

In order to achieve the above object, the following solution is adopted in the present invention. That is, as described in claim 1 in the claims,
In a hybrid vehicle control device including an engine and a traveling motor,
Output control means for controlling the engine torque and the engine speed based on a high efficiency control line set with priority on fuel efficiency so that the engine output is determined based on preset conditions;
Acceleration detection means for detecting a value related to the driver's acceleration request;
When the acceleration detection means detects that the driver's acceleration request is large, the engine control speed used by the output control means is larger than that based on the high efficiency control line. Control line changing means for changing to an acceleration control line set to be,
It is supposed to be equipped with. According to the above solution, the engine output is normally controlled based on the high-efficiency control line, and fuel efficiency is improved. And when the big acceleration request | requirement is detected, since it changes to the control line for acceleration and the raise degree of an engine speed is enlarged, the driver | operator can fully experience that it is accelerating.

A preferred mode based on the above solution is as described in claim 2 and the following claims. That is,
Traveling state detection means for detecting that the vehicle is in a specific traveling state set in advance;
When the specific driving state is detected by the driving state detection unit, a prohibiting unit for prohibiting a change to the acceleration control line;
Is further provided (corresponding to claim 2). In this case, when the vehicle is in a specific driving state, particularly a driving state in which a passenger or the like does not want to generate a loud noise, the change to the acceleration control line is prohibited, and the degree of increase in the engine speed at which a loud noise is generated is prohibited. It can be prevented from becoming large.

The engine output is set to be transmitted to the drive wheels via the automatic transmission,
As a shift mode of the automatic transmission, an automatic shift mode for performing automatic shift based on a preset shift characteristic and a manual mode for changing a shift stage every time a manual operation is performed can be selected.
The specific running state is when the automatic transmission mode is selected;
(Corresponding to claim 3). In this case, the manual mode is selected when the driver is actively enjoying the driving. At this time, the change to the acceleration control line is allowed and the acceleration feeling can be fully experienced. When the automatic transmission mode is selected, the driver wants to be in a relatively quiet driving state. At this time, the driver who prohibits the change to the acceleration control line and wants a gentle driving It will respond to your will.

  The specific running state is such that the audio device is turned on and the audio volume is below a predetermined volume (corresponding to claim 4). In this case, when the volume of the audio is low, it is when listening quietly, and at this time, it is preferable to prohibit the change to the acceleration control line and maintain a quiet state.

  The specific traveling state is set to be determined when the navigation device determines that the vehicle is traveling in an urban area (corresponding to claim 5). In this case, when driving in an urban area, it is when driving while paying attention to the surroundings, so at this time prohibiting changes to the acceleration control line so that quiet driving is performed, When traveling on an expressway or the like where the concern for the vehicle becomes relatively small, the change to the acceleration control line is allowed and the acceleration can be fully experienced.

  When changing to the acceleration control line, the power generation amount of the generator driven by the engine is reduced (corresponding to claim 6). In this case, by reducing the power generation amount of the generator driven by the engine, the degree of increase in the engine speed can be reliably and quickly increased.

  According to the present invention, acceleration can be fully experienced while improving fuel efficiency.

  In FIG. 1, reference numeral 1 denotes a travel motor. The travel motor 1 drives left and right drive wheels (front wheels or rear wheels) 3 </ b> R, 3 </ b> L via a differential gear 2. Reference numeral 10 denotes an engine, and the generator 11 is driven by the engine 10 to generate power. In the embodiment, the engine 10 is set to function exclusively for power generation (the drive wheels are not directly driven by the engine 10). Power generated by the generator 11 is supplied to the motor 1, while surplus power is supplied to the high voltage battery 13 via the inverter / converter 12. Further, during regenerative braking, the electric power generated by the motor 1 is supplied to the battery 13 via the inverter / converter 12.

  FIG. 2 shows an example of a control system of the present invention. U is a controller (control unit) configured using a microcomputer. The controller U includes a motor controller 31 for controlling the motor 1, a controller 32 for controlling the generator 11 (controlling the load for power generation), and a throttle valve 33 for controlling the output of the engine 10. Control. Each signal from various sensors or switches 21 to 26 is input to the controller U. The sensor 21 detects the engine speed. The sensor 22 detects the throttle opening. The sensor 23 detects the accelerator opening. The sensor 24 is for use in another embodiment, and is a shift mode detection sensor. The sensor 25 detects the volume of audio installed in the vehicle. The sensor 26 is an antenna and detects the current position of the vehicle for the navigation device.

  FIG. 3 shows control lines and the like used by the controller U for engine output control. In FIG. 3, the balance torque indicated by the vertical axis is a torque that balances the engine torque and the torque of the motor 1. What is indicated by a symbol P is an equal output line of the motor 1. The reference sign Q indicates the maximum torque line of the engine 10. A substantially circular line is an equi-efficiency line, and the closer to the center, the higher the efficiency. An area indicated by reference numeral S that is the area closest to the center of the circle in the equal efficiency line is an area where the combination efficiency of the engine 10 and the generator 11 is good (the product of the engine thermal efficiency and the generator efficiency is predetermined). High-efficiency region that exceeds the value). A solid line and a line indicated by a symbol L are high-efficiency control lines, and output control of the engine 10 is basically performed based on the high-efficiency control line L. Note that the low engine speed range indicated by the symbol L1 is a region where sufficient engine output (power generation by the generator 11) cannot be obtained to such an extent that the vehicle is driven, and the region indicated by L1 is exclusively from the battery 13. The motor 1 is driven by the power supply. The region indicated by the symbol L2 is a region exceeding the maximum torque of the engine 10, and in addition to the maximum generated power from the generator 11 (the engine 10 is in the maximum output state), the battery 13 also supplies power to the motor 1. It becomes an area to be done.

  Here, in the embodiment, since the driving wheels 3R and 3L are driven only by the motor 1, the motor output is always equal to the required output (required driving force) of the vehicle. In addition, when the amount of power stored in the battery 13 is small, it is necessary to generate power for charging the battery 13 in addition to supplying power to the motor 1. The required output) may be larger than the required output of the vehicle. That is, the engine 10 is basically controlled to have the engine torque and the engine speed based on the above-described high-efficiency control line L, and all the generated power obtained by the operation based on the high-efficiency control line L is motor. 1 may be used not only for power supply to 1 (for running the vehicle) but also for charging the battery 13. It should be noted that how the electric power generated by the generator 11 is distributed between the power supply to the motor 1 and the charging of the battery 13, for example, how the engine output is determined based on the required output of the vehicle, the required power generation amount, etc. As to whether or not to do so, various settings can be made as is well known, and further detailed description is omitted.

  Next, the output control of the engine 10 during acceleration, which is a feature of the present invention, will be described. First, FIG. 4 shows the output control at the time of slow acceleration. When the slow acceleration is detected at the α point, the target engine output is determined as the β point on the high efficiency control line L. Since it is a slow acceleration time, the driver does not require acceleration until the driver fully feels acceleration. Therefore, the engine torque and engine speed of the engine 10 are always controlled with high efficiency from the α point to the β point. The value is controlled based on the line L.

  On the other hand, during sudden acceleration, when shifting from the α point to the β point, the power generation load on the generator 11 is temporarily reduced, and the engine speed is greatly increased so as to pass through the γ point in FIG. The output is controlled so as to reach the β point. More specifically, as indicated by reference numeral X1 in FIG. 3, an acceleration control line is set so that the engine speed is larger than that of the high-efficiency control line L. During sudden acceleration, engine output control is performed. Is changed from the high-efficiency control line L to the acceleration control line X1. When the power generation load of the generator 11 is reduced, it is preferable to supply sufficient power to the motor 1 from the battery 13 to supply electric power corresponding to the reduced generation power to the motor 1. In addition, the degree of increase in the engine speed is increased at the beginning of acceleration (up to the point γ in FIG. 5), but the driver feels acceleration by increasing the engine speed immediately after the acceleration request operation. It becomes possible to fully experience acceleration.

  The flowchart in FIG. 6 shows an example of engine output control by the controller U. FIG. 6 shows a control example in which attention is paid to a portion of which one of the high efficiency control line L and the acceleration control line X1 is selected. . Hereinafter, the flowchart of FIG. 6 will be described. In the following description, S represents a step.

  First, after the accelerator opening is read in S1, it is determined in S2 whether or not the change amount (depression increase amount) of the accelerator opening is a predetermined value or more. If the determination in S2 is YES, it is during rapid acceleration. At this time, it is determined whether or not the conditions for changing to the acceleration control line X1 are satisfied by the determination processing in S3 to S6. That is, in S3, the operating state of the audio device and the current position information of the vehicle in the navigation device are read. Thereafter, in S5, it is determined whether or not the audio apparatus is turned on and the volume exceeds a predetermined volume. If the determination in S5 is YES, it is determined in S6 whether or not the vehicle is currently traveling on a suburb or highway. If the determination in S6 is YES, the acceleration control line X1 is set in S7. In S8, the output control of the engine 10 is executed by the control line X1 selected in S7.

  When the determination at S2 is NO, the determination at S5 is NO, or the determination at S6 is NO, the high efficiency control line L is selected as the control line at S9. When S9 is passed, the output control of the engine 10 is executed in S8 by the high efficiency control line L selected in S9.

  FIG. 7 shows another embodiment of the present invention, which is a modification of FIG. In the present embodiment, the driving wheels are also driven by the engine 10 (may be the same driving wheels as the driving wheels driven by the motor 1 or may be different driving wheels). It is assumed that an automatic transmission is interposed between the engine 10 and the drive wheels. As a shift mode of the automatic transmission, an automatic shift mode in which automatic shift is performed and a manual mode in which a shift stage is changed each time a predetermined manual operation is performed by a driver can be changed (selected) by manual operation. It is assumed that In this embodiment, steps S3 and S4 are added as compared with the case of FIG. 6, and the selected shift mode is read in S3, and whether or not the manual mode is selected in S4. When the manual mode is selected, the process proceeds to S5 (when the automatic transmission mode is selected, the selection of the acceleration control line X1 is prohibited).

  Although the embodiment has been described above, the present invention is not limited to the embodiment, and can be appropriately changed within the scope described in the scope of claims. For example, the invention includes the following cases. . At the time of larger (steeper) acceleration, for example, as shown by reference numeral X2 in FIG. 3, not only the high-efficiency control line L but also an acceleration control line in which the engine speed increases further than the acceleration control line X1. It can also be set. That is, the number of acceleration control lines is not limited to one, and a plurality of acceleration control lines can be set according to the degree of acceleration. 6 or 7, the steps S5, S6, and S4 are set as AND conditions, but they may be set as OR conditions. That is, when the audio device is turned on and the volume exceeds a predetermined amount, the acceleration control line may be selected regardless of other conditions. The acceleration control line may be selected regardless of other conditions, and when the manual mode is selected as the shift mode, the acceleration control line is selected regardless of other conditions. You may do it. In addition, as a specific running state that is a condition for prohibiting the change to the acceleration control line X1 (or X2), the driver generates a loud sound caused by an increase in the engine speed. It is possible to set an appropriate driving state that is not desired, for example, while talking on a mobile phone (during a voice conversation), while operating various switches (the driver's feelings are concentrated on the operation of the switches). Etc.) For detecting the acceleration request, various conventionally known methods can be adopted. For example, it can be determined that the acceleration request is large when the depression speed of the accelerator opening is equal to or higher than a predetermined value. Of course, the object of the present invention is not limited to what is explicitly stated, but also implicitly includes providing what is substantially preferred or expressed as an advantage.

1 is an overall system diagram showing an embodiment of the present invention. The block diagram which shows the example of a control system of this invention. The figure which shows a high efficiency control line, the control line for acceleration, etc. The figure which shows the state of the output control at the time of slow acceleration. The figure which shows the state of the output control at the time of sudden acceleration. The flowchart which shows the example of control of this invention. FIG. 7 is a flowchart corresponding to FIG. 6, showing another embodiment of the present invention.

Explanation of symbols

1: Driving motor 3R, 3L: Drive wheel 10: Engine 11: Generator 13: Battery U: Controller L: High efficiency control line X1: Acceleration control line X2: Acceleration control line

Claims (6)

In a hybrid vehicle control device including an engine and a traveling motor,
Output control means for controlling the engine torque and the engine speed based on a high efficiency control line set with priority on fuel efficiency so that the engine output is determined based on preset conditions;
Acceleration detection means for detecting a value related to the driver's acceleration request;
When the acceleration detection means detects that the driver's acceleration request is large, the engine control speed used by the output control means is larger than that based on the high efficiency control line. Control line changing means for changing to an acceleration control line set to be,
A control apparatus for a hybrid vehicle, comprising: In claim 1,
Traveling state detection means for detecting that the vehicle is in a specific traveling state set in advance;
When the specific driving state is detected by the driving state detection unit, a prohibiting unit for prohibiting a change to the acceleration control line;
A control apparatus for a hybrid vehicle, further comprising: In claim 2,
The engine output is set to be transmitted to the drive wheels via the automatic transmission,
As a shift mode of the automatic transmission, an automatic shift mode for performing automatic shift based on a preset shift characteristic and a manual mode for changing a shift stage every time a manual operation is performed can be selected.
The specific running state is when the automatic transmission mode is selected;
A control apparatus for a hybrid vehicle characterized by the above. In claim 2,
The control apparatus for a hybrid vehicle, characterized in that the specific running state is when the audio device is turned on and the audio volume is equal to or lower than a predetermined volume. In claim 2,
The control apparatus for a hybrid vehicle, characterized in that the specific traveling state is determined to be traveling in an urban area by a navigation device. In any one of Claims 1 thru | or 5,
The hybrid vehicle control device according to claim 1, wherein, when the acceleration control line is changed, a power generation amount of a generator driven by an engine is reduced.