JP2002199504A - Hybrid vehicle and its control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent generation of vibration accompanying application of a braking power, and to enhance the comfort of cruising. SOLUTION: This invention is equipped with an engine 11, a generator motor 16 mechanically connected to the engine 11 and driving wheels, a control request determining processing means 91 which determines whether a request to put brake on a hybrid vehicle is made or not, and a torque control processing means 93 which stops the drive of the engine 11 and controls torque of the generator motor 16 when the request to brake the hybrid vehicle is made. When a request to brake the hybrid vehicle is made, the drive of the engine 11 is stopped and the torque of the generator motor 16 is controlled. A braking power can be generated by idling of the engine 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid vehicle and a control method thereof.

[0002]

2. Description of the Related Art Conventionally, in a hybrid vehicle,
A planetary gear unit having a sun gear, a ring gear, and a carrier; connecting the carrier to an engine; connecting a ring gear to a drive wheel; connecting a sun gear to a generator motor; and outputting from the ring gear and the drive motor. The generated rotation is transmitted to the driving wheels to generate a driving force.

When the hybrid vehicle needs to be braked while the hybrid vehicle is running by driving the engine and the drive motor, a braking force is generated by performing regeneration by the drive motor. Let me do. In this case, the current generated during the regeneration by the drive motor is sent to the battery and the battery is charged. However, if the remaining battery power is large, the battery cannot be charged. as a result,
The regeneration by the drive motor cannot be performed, and a sufficient braking force cannot be generated.

Therefore, when the remaining battery power is large, the driving of the engine is stopped, and the generator motor is driven.
Run the engine idling and slide on the engine
There has been provided a hybrid vehicle in which a braking force is generated using dynamic resistance (Japanese Patent No. 3050138).
No.). In this case, a braking torque required to brake the hybrid vehicle is calculated based on the amount of depression of the brake pedal, and a target value of the engine rotation speed, that is, a target engine rotation speed is calculated based on the calculated braking torque. It is possible to calculate the target value of the generator motor rotation speed based on the calculated target engine rotation speed, that is, the target generator motor rotation speed, and achieve the calculated target generator motor rotation speed. In addition, the rotation speed of the generator motor is controlled.

[0005]

However, in the above-mentioned conventional hybrid vehicle, when the rotation speed of the generator motor is controlled, disturbance due to unevenness of the road surface or the like is applied to the generator motor via driving wheels. If this occurs, the torque of the generator motor, that is, the generator motor torque fluctuates, and vibration occurs in the hybrid vehicle, resulting in a reduced running feeling.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the conventional hybrid vehicle, and can prevent the occurrence of vibration accompanying the generation of braking force, thereby improving the driving feeling. It is an object of the present invention to provide a hybrid vehicle and a control method thereof.

[0007]

Therefore, in the hybrid vehicle according to the present invention, there is a demand for an engine, a generator motor mechanically connected to the engine and driving wheels, and braking of the hybrid vehicle. And a torque control processing means for stopping the driving of the engine and controlling the torque of the generator motor when a request to brake the hybrid vehicle is made.

[0008] Another hybrid vehicle of the present invention further includes a battery state detecting means for detecting the state of the battery.

The torque control processing means, when a request to brake the hybrid vehicle is made, stops driving of the engine in accordance with the state of the battery and controls torque of the generator motor. Do.

In still another hybrid type vehicle according to the present invention, the torque control processing means may further include a step of driving the engine when at least one of the remaining battery level and the battery voltage is larger than a threshold value. Is stopped and the torque of the generator motor is controlled.

In still another hybrid vehicle according to the present invention, it is necessary to drive the hybrid vehicle based on a variable corresponding to the rotation speed of the drive wheels and the amount of operation of the operating means by the driver. Target output torque calculation processing means for calculating the target output torque.

Then, the torque control processing means calculates a target generator motor torque corresponding to the target output torque, and drives the generator motor to generate a target generator motor torque.

Still another hybrid vehicle according to the present invention further includes a drive motor, an output shaft connected to the drive wheels, and at least three gear elements, wherein each gear element includes an engine, a generator motor and A differential gear connected to the output shaft.

In the control method for a hybrid vehicle according to the present invention, it is determined whether or not a request to brake the hybrid vehicle has been made, and when the request to brake the hybrid vehicle has been made, the driving of the engine is stopped; In addition, torque control of the generator motor is performed.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a functional block diagram of a hybrid vehicle according to an embodiment of the present invention.

In the figure, 11 is an engine, 16 is a generator motor, 91 is a braking request determination processing means for determining whether or not a request has been made to brake the hybrid vehicle, 9
Reference numeral 3 denotes a torque control processing unit that stops driving of the engine 11 and controls torque of the generator motor 16 when a request to brake the hybrid vehicle is issued.
Reference numeral 92 denotes a battery state detecting means (not shown) for detecting the state of the battery.

FIG. 2 is a conceptual diagram of a hybrid vehicle according to an embodiment of the present invention.

In FIG. 1, reference numeral 11 denotes an engine (E / G) disposed on a first axis, and reference numeral 12 denotes an engine (E / G) disposed on the first axis, which is generated by driving the engine 11. An output shaft for outputting rotation, 13 is disposed on the first axis, and a planetary gear unit as a differential gear device for performing a speed change with respect to the rotation input via the output shaft 12, and 14 is An output shaft, which is disposed on one axis line and outputs the rotation after shifting in the planetary gear unit 13, 15 is a first counter drive gear as an output gear fixed to the output shaft 14, and 16 is the A first electric motor, which is arranged on one axis and is connected to the planetary gear unit 13 via a transmission shaft 17 similarly arranged on the first axis, and further mechanically connected to the engine 11. A generator motor (G) as a.

The output shaft 14 has a sleeve shape and is disposed so as to surround the output shaft 12. Further, the first counter drive gear 15 is a planetary gear unit 1.
3 is provided on the engine 11 side.

The planetary gear unit 13
Is a sun gear S as a first gear element, the sun gear S
The sun gear comprises a pinion P meshing with the pinion P, a ring gear R serving as a second gear element meshing with the pinion P, and a carrier CR serving as a third gear element rotatably supporting the pinion P. S is a generator motor 16 via the transmission shaft 17 and a ring gear R is an output shaft 14
And a driving wheel 37 via a predetermined gear train, and a carrier CR.
Is connected to the engine 11 via the output shaft 12. A one-way clutch F is disposed between the carrier CR and the case 10 of the driving device, and the one-way clutch F rotates the carrier CR from the engine 11 in the forward direction.
When the rotation is transmitted to the carrier CR from the generator motor 16 or the drive motor 25, the rotation is locked.
To be transmitted to 1.

Further, the generator motor 16 is fixed to the transmission shaft 17 and is rotatably disposed.
1, a stator 22 disposed around the rotor 21 and a coil 23 wound around the stator 22. The generator motor 16 generates electric power by rotation transmitted through a transmission shaft 17. The coil 23 is connected to a battery (not shown) and supplies a direct current to the battery. A brake B is provided between the rotor 21 and the case 10, and by engaging the brake B, the rotor 21 can be fixed and the rotation of the generator motor 16 can be stopped.

Further, reference numeral 25 denotes a second parallel to the first axis.
And a drive motor (M) 26 as a second electric motor, which is mechanically connected to the generator motor 16 with each other, is disposed on the second axis, and the drive motor 25 Reference numeral 27 denotes a second counter drive gear as an output gear fixed to the output shaft 26. The drive motor 25 is connected to the output shaft 2.
6, the rotor 40 is rotatably disposed, a stator 41 disposed around the rotor 40, and a coil 42 wound around the stator 41.

The drive motor 25 generates a drive motor torque by a current supplied to the coil 42. To that end, the coil 42 is connected to the battery,
DC current from the battery is converted into AC current and supplied. The generator motor 16
The drive motor 25 and the drive wheel 37 are mechanically connected.

In order to rotate the drive wheels 37 in the same direction as the rotation of the engine 11, a counter shaft 30 is disposed on a third axis parallel to the first and second axes. A first counter driven gear 31 and a first counter driven gear 3
The second counter driven gear 32 having more teeth than one is fixed. Further, the first counter driven gear 31
And the first counter drive gear 15 are meshed with each other, and the second counter driven gear 32 and the second counter drive gear 27 are meshed with each other, and the rotation of the first counter drive gear 15 is reversed. The rotation of the second counter drive gear 27 is inverted by the first counter driven gear 31 and transmitted to the second counter driven gear 32.

Further, a differential pinion gear 33 having fewer teeth than the first counter driven gear 31 is fixed to the counter shaft 30.

A differential device 36 is provided on a fourth axis parallel to the first to third axes.
The differential ring gear 35 of the differential device 36 meshes with the differential pinion gear 33. Therefore, the rotation transmitted to the differential ring gear 35 is distributed by the differential device 36 and the driving wheels 37
Is transmitted to Reference numeral 38 denotes a generator motor rotation speed sensor for detecting a generator motor rotation speed NG indicating the rotation speed of the generator motor 16, and 39 denotes a drive motor rotation speed for detecting a drive motor rotation speed NM indicating the rotation speed of the drive motor 25. It is a speed sensor.

Thus, not only can the rotation generated by the engine 11 be transmitted to the first counter driven gear 31, but also the rotation generated by the drive motor 25 can be transmitted to the second counter driven gear 32.
, The hybrid vehicle can be driven by driving the engine 11 and the drive motor 25.

Next, a control device for a hybrid vehicle having the above configuration will be described.

FIG. 3 is a block diagram showing a control device for a hybrid vehicle according to an embodiment of the present invention.

In the figure, 11 is an engine, 16 is a generator motor, 25 is a drive motor, and 43 is a battery.
Reference numeral 46 denotes an engine control device as engine control means for controlling the engine 11. The engine control device 46 includes an engine rotation speed NE indicating the rotation speed of the engine 11 detected by the engine rotation speed sensor 71.
And sends an instruction signal such as the throttle opening θ to the engine 11. Reference numeral 47 denotes a generator motor control device as generator motor control means for controlling the generator motor 16, and the generator motor control device 47
To the current command value IG. Reference numeral 49 denotes a drive motor control device as drive motor control means for controlling the drive motor 25. The drive motor control device 49
5 to the current command value IM.

Reference numeral 51 denotes a vehicle control device, which comprises a CPU, a storage device, and the like (not shown), and controls the overall operation of the hybrid vehicle. Reference numeral 44 denotes a battery remaining amount for detecting the remaining battery charge SOC as the state of the battery 43. A detecting device 52 is an accelerator pedal as first operating means operated by a driver, 53 is a vehicle speed sensor for detecting a vehicle speed V, and 55 is a stepping amount of the accelerator pedal 52, that is, an accelerator opening α. Accelerator switch 61 as an accelerator operation detecting means; 61, a brake pedal as a second operating means operated by the driver; 62, a brake switch as a brake operation detecting means for detecting the depression amount β of the brake pedal 61; Is a generator motor rotation speed sensor for detecting a generator motor rotation speed NG, and 39 is a drive motor rotation speed sensor. A drive motor rotational speed sensor 72 for detecting the rotational speed NM, and a battery voltage sensor 72 for detecting a battery voltage VB as the state of the battery 43. Note that the battery remaining amount detecting device 44 and the battery voltage sensor 72 constitute a battery state detecting means 92.

The vehicle control device 51 sends an engine control signal to the engine control device 46 to set the start / stop of the engine 11 or to provide the engine control device 46 with a target value of the engine rotational speed NE, that is, a target engine speed. The rotation speed NE ^* is set, and the generator motor control device 47 sets a target value of the generator motor rotation speed NG, that is,
The target generator motor rotation speed NG ^* and the target value of the generator motor torque TG, that is, the target generator motor torque TG ^* can be set, or the target value of the drive motor torque TM, The target drive motor torque TM ^* and the drive motor torque correction value δTM are set.

In this embodiment, the vehicle speed V is
Although the rotation speed is detected by the rotation speed of the output shaft 14 (FIG. 2), that is, the output rotation speed NO, it can also be detected by the rotation speed of the ring gear R, the rotation speed of the drive wheels, and the like.

Next, the operation of the hybrid vehicle having the above configuration will be described.

FIG. 4 is a flowchart showing the operation of the hybrid vehicle according to the embodiment of the present invention, FIG. 5 is a diagram showing a first vehicle driving force map according to the embodiment of the present invention, and FIG. FIG. 7 is a diagram showing a second vehicle driving force map in the embodiment, FIG. 7 is an explanatory diagram of the operation of the planetary gear unit in the embodiment of the present invention, and FIG. 8 is a vehicle speed diagram in the embodiment of the present invention. 5 and 6
In FIG. 5, the horizontal axis represents the vehicle speed V, and the vertical axis represents the vehicle driving force Q.

First, the braking request determination processing means 91 (FIG. 1) of the vehicle control unit 51 (FIG. 3) performs a braking request determination process, and determines the accelerator opening α detected by the accelerator switch 55 and the brake switch 62. The detected stepping amount β is read, and it is determined whether the driver has requested the braking of the hybrid vehicle based on, for example, the stepping value β taking a negative value. When the driver does not request the hybrid vehicle to be braked, the target output torque calculation processing unit (not shown) of the vehicle control device 51 performs a target output torque calculation process,
A variable corresponding to the rotation speed of the driving wheel 37, in this embodiment, the vehicle speed V detected by the vehicle speed sensor 53 and the throttle opening θ sent from the engine control device 46
And when the accelerator pedal 52 is depressed,
When the brake pedal 61 is depressed with reference to the first vehicle driving force map shown in FIG. 5, the vehicle speed V, the accelerator opening α and the second vehicle driving force map shown in FIG. Preset in accordance with the stepping amount β,
A vehicle driving force Q required for running the hybrid vehicle is calculated, and a target output torque TO ^* is calculated based on the calculated vehicle driving force Q. Note that the calculated target output torque TO ^* is determined by the vehicle driving force Q and the output shaft 14.
It is calculated based on the gear ratio in the torque transmission system from (FIG. 2) to the drive wheels 37.

When a request to brake the hybrid vehicle is made, the torque control processing means 93 of the vehicle control device 51 performs a torque control process in accordance with the state of the battery 43. For this purpose, the torque control condition satisfaction determination processing means (not shown) of the vehicle control device 51 performs a torque control condition satisfaction determination process, and a condition for performing torque control of the generator motor 16, that is, the torque control condition is satisfied. Determine whether or not. That is, the torque control condition satisfaction determination processing means determines that the target output torque TO
^* , The remaining battery charge SOC detected by the remaining battery detection device 44 and the battery voltage VB detected by the battery voltage sensor 72 are read, and the first condition is determined based on whether the target output torque TO ^* is negative. It is determined whether or not the second condition is satisfied based on whether or not the remaining battery charge SOC is greater than a threshold value SOCth.
It is determined whether or not the third condition is satisfied based on whether or not it is greater than th. If both the first and second conditions are satisfied, or if both the first and third conditions are satisfied, the torque control condition is determined. Is determined to be satisfied, and when the first condition is not satisfied, or when neither the second nor the third condition is satisfied, it is determined that the torque control condition is not satisfied. And
When the torque control condition is satisfied, the torque control processing means 93 sends an engine control signal to the engine control device 46 to stop driving the engine 11. Here, stopping the driving of the engine 11 does not mean that the engine 11 is mechanically locked, but means that the self-sustaining operation is stopped. Therefore, a crankshaft (not shown) can be rotated while the driving of the engine 11 is stopped. It should be noted that the fuel cut may be performed by sending a fuel cut signal to the engine control device 46 to stop driving the engine 11.

Next, the not-shown target generator motor torque setting processing means of the torque control processing means 93 performs a target generator motor torque setting process, and based on the target output torque TO ^* , sets the target generator motor torque. Calculate and set TG ^* . When a request to control the hybrid vehicle is made, the first condition is satisfied, and the target output torque TO ^* is negative and becomes the target value of the braking torque for braking the hybrid vehicle. .

The generator motor command value calculation processing means (not shown) of the generator motor control device 47 performs a generator motor command value calculation process, and receives the target generator motor torque TG ^* from the vehicle control device 51. Then, the generator motor torque command value STG ^* is calculated based on the target generator motor torque TG ^* . Subsequently, a current command value generation processing unit (not shown) of the generator motor control device 47 performs a first current command value generation process, and calculates a deviation between the generator motor torque TG and the target generator motor torque TG ^*. A current command value IG is generated so that ΔTG becomes 0, and the current command value IG is sent to the generator motor 16 to drive the generator motor 16. Thus, the torque control of the generator motor 16 is performed.

Accordingly, the engine 11 is caused to run idle, and a braking force can be generated in the hybrid vehicle using the sliding resistance of the engine 11. In this case, torque control is performed so that the generator motor torque TG becomes the target generator motor torque TG ^*. However, from the relationship of the torque balance in the planetary gear unit 13, the braking force and the generator motor torque TG are always constant. Since the proportional relationship is established, an accurate braking force can always be generated regardless of the state of the engine 11.

In addition, disturbance due to unevenness of the road surface or the like causes the driving wheels 3
Even when the torque is applied to the generator motor 16 via the motor 7, since the torque control is performed, the generator motor torque TG does not fluctuate. Therefore, generation of vibration in the hybrid vehicle can be prevented, and driving feeling can be improved.

In the planetary gear unit 13, as shown in FIG. 7, the carrier CR is the engine 11, the sun gear S is the generator motor 16, and the ring gear R is the drive wheel 37 via the output shaft 14. As a result, the rotation speed of the ring gear R is equal to the output rotation speed NO, the rotation speed of the carrier CR is equal to the engine rotation speed NE, and the rotation speed of the sun gear S is equal to the generator motor rotation speed NG. Then, since the number of teeth of the ring gear R is set to ρ times (in this embodiment, twice) the number of teeth of the sun gear S, the relationship of (ρ + 1) · NE = 1 · NG + ρ · NO is established.

The engine torque TE and the output torque T
O and the generator motor torque TG have a relationship of TE: TO: TG = (ρ + 1): ρ: 1, and mutually receive a reaction force.

When the hybrid vehicle is at a standstill, the output rotational speed NO and the engine rotational speed NE as shown by the line L1 in the vehicle speed diagram of FIG.
And the generator motor rotation speed NG is 0 [rpm]
become. When the driving of the engine 11 is stopped while the hybrid vehicle is running, the output rotation speed NO takes a positive value and the engine rotation speed NE becomes 0 [rpm], as indicated by the line L2. , And the generator motor rotation speed NG takes a negative value. And the engine 11
When the torque control is performed by driving the generator motor 16 in a state where the driving of the motor is stopped, the generator motor rotation speed NG is changed as shown by the arrow, and takes a positive value, and accordingly, the engine The rotation speed NE takes a positive value. As a result, the engine 11 is caused to idle. When the generator motor rotation speed NG takes a positive value, the generator motor 16 is driven as an electric motor.
Is supplied to the generator motor 16 and the battery 43 is discharged.

In this way, a current command value IG is generated in correspondence with the target generator motor torque TG ^* , and the current command value IG is sent to the generator motor 16, and the generator motor 16 is driven to Perform control.

Incidentally, as described above, the engine torque TE, the output torque TO, and the generator motor torque TG
Receive a reaction force with each other, so that when the generator motor 16 is driven to perform torque control, the generator motor torque TG is converted to a ring gear torque TR and output from the ring gear R. In addition, the generator motor rotation speed NG fluctuates, the ring gear torque TR fluctuates, and the fluctuating ring gear torque TR is transmitted to the drive wheels 37, so that the running feeling of the hybrid vehicle decreases. Therefore, the drive motor torque TM is corrected by the variation of the ring gear torque TR, and the drive motor torque correction value δTM is sent to the drive motor control device 49.

For this purpose, the generator motor control device 4
7, a generator motor torque calculation processing means (not shown)
A generator motor torque calculation process is performed, and the vehicle control device 51
The generator motor rotation speed NG is read through the controller, a generator motor torque TG corresponding to the generator motor rotation speed NG is calculated with reference to a generator motor torque map (not shown), and the calculated generator motor torque TG is calculated. This is sent to the vehicle control device 51.

The drive motor torque correction value calculation processing means (not shown) of the vehicle control device 51 performs a drive motor torque correction value calculation process, and outputs the generator motor torque TG, And second counter drive gear 27 for the number of teeth of sun gear S
, Ie, the drive motor torque correction value δTM is calculated based on the gear ratio γ1 between the generator motor 16 and the drive motor 25.

In this case, the drive motor torque correction value δ
TM is calculated as follows. That is, when the inertia of the generator motor 16 is InG and the angular acceleration (rate of change in rotation) of the generator motor 16 is αG, the sun gear torque TS applied to the sun gear S is TS = TG + InG · αG. Since the angular acceleration αG is extremely small,
By approximating the sun gear torque TS and the generator motor torque TG, TS = TG can be obtained. If the number of teeth of the ring gear R is ρ times the number of teeth of the sun gear S, then the ring gear torque TR is ρ times the sun gear torque TS, so that TR = ρ · TS = ρ · TG.

As described above, the ring gear torque TR can be calculated from the generator motor torque TG. Then, assuming that the counter gear ratio, i.e., the ratio of the number of teeth of the second counter drive gear 27 to the number of teeth of the second counter driven gear 32 is i, the drive motor torque correction value δTM is δTM = ρ · TS · i = Ρ · TG · i. Since the gear ratio γ1 is γ1 = ρ · i, the drive motor torque correction value δTM is δTM = γ1 · TG.

Subsequently, a target drive motor torque setting processing means (not shown) of the vehicle control device 51 performs a target drive motor torque setting process and outputs the target output torque TO ^*.
By subtracting the target generator motor torque TG ^* from, the shortage of the generator motor torque TG is calculated and set as the target drive motor torque TM ^* ,
The target drive motor torque TM ^* and the drive motor torque correction value δTM are sent to the drive motor control device 49. And
The drive motor command value calculation means (not shown) of the drive motor control device 49 receives the target drive motor torque TM ^* and the drive motor torque correction value δTM from the vehicle control device 51, and calculates the target drive motor torque TM ^* from the target drive motor torque TM ^*. The drive motor torque correction value δTM is subtracted to calculate the drive motor torque command value STM ^* STM ^* = TM ^* −δTM.

Subsequently, current command value generation processing means (not shown) of the drive motor control device 49 performs a second current command value generation process, and calculates a deviation between the drive motor torque TM and the drive motor torque command value STM ^*. A current command value IM is generated so that ΔTM becomes 0, and the current command value IM is sent to the drive motor 25. Thus, the torque control is performed.

On the other hand, when the torque control condition is not satisfied,
The control of the generator motor 16 is performed without stopping the driving of the engine 11.

That is, the engine target operating state setting processing means (not shown) of the torque control processing means 93 performs the engine target operating state setting processing, and refers to the engine target operating state map (not shown) to determine the efficiency of the engine operating points. Is set as the engine target operating state, and the engine speed NE in the engine target operating state is set to the target engine speed N.
Calculated as E ^* . Subsequently, the vehicle control device 51 calculates a target generator motor rotation speed NG ^* . For this purpose, the vehicle control device 51 reads the vehicle speed V, and calculates the output rotational speed NO by the following equation based on the vehicle speed V and the gear ratio GO from the planetary gear unit 13 to the drive wheels 37.

NO = V · GO Then, the target generator motor rotation speed setting processing means (not shown) of the vehicle control device 51 performs a target generator motor rotation speed setting process, and executes the target engine rotation speed NE.
^{Based on *} and the output rotation speed NO, the target generator motor rotation speed NG ^* is calculated by the following equation, set, and sent to the generator motor control device 47.

NG ^* = NO− (NO−NE ^* ) · (1 + ρ) / ρ Further, the current command value generation processing means of the generator motor control device 47 performs a third current command value generation process, When the target generator motor rotation speed NG ^* is sent from the vehicle control device 51, the current command value IG is set so that the deviation ΔNG between the generator rotation speed NG and the target generator motor rotation speed NG ^* becomes zero. Then, the current command value IG is sent to the generator motor 16 and the generator motor 16 is driven to control the rotation speed.

In the present embodiment, since the torque control of the generator motor 16 is performed irrespective of the state of the engine 11, the engine 11 blows up and the engine speed NE increases. May be higher than necessary. Therefore, the generator motor torque TG1 corresponding to the sliding resistance in the engine 11 is calculated, and the generator motor torque TG1 is set as the generator motor torque limit value TGL1, and the target drive motor torque TM ^{* is set.}
Is set so as not to exceed the generator motor torque limit value TGL1.

Further, the upper limit value NE of the engine speed NE
L, an upper limit value NGL of the generator motor rotation speed NG is calculated based on the upper limit value NEL and the vehicle speed V, and the generator motor torque TG is set based on the upper limit value NGL.
2, the generator motor torque TG2 may be set as the generator motor torque limit value TGL2, and the target drive motor torque TM ^* may be set so as not to exceed the generator motor torque limit value TGL2.

If the engine speed NE is excessively low, for example, lower than the idle speed, cranking vibration occurs in the engine 11. Therefore,
It is also possible to set the idle speed as the lower limit value of the engine speed NE so that the engine speed NE is equal to or higher than the idle speed. Also, the engine 11
When the generator motor 16 and the generator motor 16 are connected via a damper, the engine speed NE may be higher than the speed at which a resonance phenomenon occurs due to the damper.

Next, the flowchart will be described. Step S1 Accelerator opening α and brake pedal 61
Is read. Step S2: Calculate the target output torque TO ^* . Step S3: Battery SOC and battery voltage V
Read B. Step S4: The target output torque TO ^* is negative (TO
^* Determine whether <0). If the target output torque TO ^* is negative, the process proceeds to step S5, where the target output torque TO ^*
If is not negative, the process proceeds to step S6. Step S5: It is determined whether or not the remaining battery charge SOC is larger than a threshold value SOCth. When the remaining battery charge SOC is larger than the threshold SOCth, the process proceeds to step S9, and when the remaining battery SOC is equal to or less than the threshold SOCth, the process proceeds to step S8. Step S6: An engine target operating state setting process is performed. Step S7 A target generator motor rotation speed setting process is performed, and the process proceeds to step S11. Step S8: It is determined whether or not the battery voltage VB is higher than the threshold value VBth. Battery voltage VB is equal to threshold VB
If it is larger than th, the process proceeds to step S9 where the battery voltage V
If B is equal to or smaller than the threshold value VBth, the process proceeds to step S6. Step S9: The driving of the engine 11 is stopped. Step S10 A target generator motor torque setting process is performed. Step S11: The ring gear torque TR is calculated from the generator motor torque TG. Step S12 A target drive motor torque setting process is performed, and the process ends.

The present invention is not limited to the above embodiment, but can be variously modified based on the gist of the present invention, and they are not excluded from the scope of the present invention.

[0063]

As described in detail above, according to the present invention, in a hybrid vehicle, an engine, a generator motor mechanically connected to the engine and driving wheels, and a brake for the hybrid vehicle are provided. Braking request determination processing means for determining whether a request has been made to stop the engine, and torque control processing means for stopping the driving of the engine and controlling the torque of the generator motor when a request to brake the hybrid vehicle has been made. And

In this case, when a request is made to brake the hybrid vehicle, the driving of the engine is stopped and the torque of the generator motor is controlled.

Therefore, the engine is run idle,
A braking force can be generated in the hybrid vehicle using the sliding resistance of the engine. Further, since the torque control of the generator motor is performed to generate the braking force, an accurate braking force can always be generated regardless of the state of the engine.

Further, even if disturbance due to irregularities on the road surface is applied to the generator motor via the drive wheels, the torque control is performed, so that the generator motor torque does not fluctuate. Therefore, generation of vibration in the hybrid vehicle can be prevented, and driving feeling can be improved.

[Brief description of the drawings]

FIG. 1 is a functional block diagram of a hybrid vehicle according to an embodiment of the present invention.

FIG. 2 is a conceptual diagram of a hybrid vehicle according to an embodiment of the present invention.

FIG. 3 is a block diagram illustrating a control device for a hybrid vehicle according to an embodiment of the present invention.

FIG. 4 is a flowchart showing an operation of the hybrid vehicle according to the embodiment of the present invention.

FIG. 5 is a diagram showing a first vehicle driving force map according to the embodiment of the present invention.

FIG. 6 is a diagram showing a second vehicle driving force map according to the embodiment of the present invention.

FIG. 7 is an operation explanatory view of the planetary gear unit in the embodiment of the present invention.

FIG. 8 is a vehicle speed diagram in the embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 11 engine 16 generator motor 43 battery 91 braking request determination processing means 92 battery state detection means 93 torque control processing means

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[Procedure amendment]

[Submission date] January 19, 2001 (2001.1.1)
9)

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] Fig. 5

[Correction method] Change

[Correction contents]

FIG. 5

[Procedure amendment 2]

[Document name to be amended] Drawing

[Correction target item name] Fig. 6

[Correction method] Change

[Correction contents]

FIG. 6

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02D 29/02 341 F02D 29/02 341 41/04 330 41/04 330G // B60K 6/02 ZHV B60K 9 / 00 ZHVE (72) Inventor Hiroyuki Kojima 10th Takane, Fujii-machi, Anjo-shi, Aichi F-term in Aisin AW Co., Ltd. 3G093 AA07 AA16 BA22 BA33 CB07 DA01 DA06 DB00 DB03 DB05 DB15 DB19 EA05 EB00 EB04 FA11 FB02 3G301 HA00 JA00 JA37 KA16 MA24 NA08 PA11Z PE01Z PF01Z PF03Z PF05Z PG01Z 5H115 PA01 PG04 PU25 Q01 TB03 TO04

Claims (6)

[Claims] An engine, a generator motor mechanically connected to the engine and driving wheels, braking request determination processing means for determining whether a request to brake the hybrid vehicle has been made, and a hybrid vehicle. A hybrid vehicle comprising: torque control processing means for stopping driving of an engine and controlling torque of a generator motor when a request for braking is issued. 2. The vehicle according to claim 1, further comprising: a battery state detecting unit configured to detect a state of the battery, wherein the torque control processing unit is configured to correspond to the state of the battery when a request to brake the hybrid vehicle is made. The hybrid vehicle according to claim 1, wherein driving is stopped and torque control of the generator motor is performed. 3. The torque control processing means, when at least one of the remaining battery charge and the battery voltage is larger than a threshold value, stops driving of the engine and performs torque control of the generator motor. A hybrid vehicle according to claim 1. 4. A target output torque calculation processing means for calculating a target output torque required for running a hybrid vehicle based on a variable corresponding to a rotation speed of a driving wheel and an operation amount of an operation means by a driver. And having
The torque control processing means according to claim 1, wherein a target generator motor torque corresponding to the target output torque is calculated, and the generator motor is driven to generate a target generator motor torque. 5. A hybrid vehicle as described. 5. A differential gear device comprising a drive motor, an output shaft connected to drive wheels, and at least three gear elements, each gear element being connected to an engine, a generator motor, and an output shaft. The hybrid vehicle according to any one of claims 1 to 4, comprising: Determining whether or not a request to brake the hybrid vehicle has been made, and stopping the driving of the engine if the request to brake the hybrid vehicle has been made;
A method for controlling a hybrid vehicle, wherein torque control of a generator motor is performed.