JP2000224713A - Hybrid vehicle and its controlling method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To implement a power source brake with accuracy in correspondence to instructions of a driver in an electric vehicle. SOLUTION: The power system of a vehicle is formed by series-connecting an engine 10, a motor 20, a torque converter 30, a transmission 100 and axles 17. The transmission is so constructed that the gear ratio can be changed through control by a control unit 70. A driver can operate the shift lever and the like in the car to instruct deceleration by a power source brake. The control unit refers to a map and selects a speed corresponding to the instructed deceleration. When the accelerator is turned off, the torque of the motor is feedback- controlled based on a detection signal from an acceleration sensor mounted on the vehicle so that braking is implemented at the requested deceleration.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid vehicle using an engine and an electric motor as power sources and a control method thereof, and more particularly to a hybrid vehicle capable of traveling at an arbitrary target acceleration and a control method for realizing the traveling.

[0002]

2. Description of the Related Art In recent years, as one form of a hybrid vehicle, a hybrid vehicle using an engine and an electric motor as power sources has been proposed. For example, in the hybrid vehicle described in Japanese Patent Application Laid-Open No. 9-37407, an electric motor is added in series between the engine and the transmission to the power system of a normal vehicle in which the output shaft of the engine is connected to the drive shaft via the transmission. This is a vehicle having the following configuration. According to such a configuration, it is possible to travel using both the engine and the electric motor as power sources. Generally, when the vehicle starts moving, the fuel efficiency of the engine is poor. The hybrid vehicle avoids such driving,
Start using the power of the electric motor. After the vehicle reaches a predetermined speed, the engine is started and the vehicle runs using the power. Therefore, the hybrid vehicle can improve fuel efficiency at the time of starting. In addition, hybrid vehicles
The rotation of the drive shaft can be regenerated as electric power by the electric motor to perform braking (hereinafter, such braking is referred to as regenerative braking). A hybrid vehicle can use kinetic energy without waste by regenerative braking. Due to these features, the hybrid vehicle has an advantage of excellent fuel economy.

Generally, when a vehicle is running, a driver adjusts the amount of depression of an accelerator pedal so that a desired acceleration can be obtained. In a hybrid vehicle, a target torque output from an engine and an electric motor is set according to the amount of depression of an accelerator pedal, and the vehicle runs while controlling the respective operations so that the torque is output. In order to improve the operability of the vehicle, it is desirable that acceleration be performed at a desired acceleration without frequently adjusting the depression amount of the accelerator pedal during acceleration.

In order to improve the operability of a vehicle,
It is desirable that braking at the deceleration intended by the driver can be easily realized. In general, a vehicle is braked by pressing a pad or the like in response to operation of a brake pedal to apply friction to an axle (hereinafter simply referred to as a wheel brake) or driven from a power source like a so-called engine brake. There is a braking method for applying a load to a shaft (hereinafter, referred to as a power source brake). In a hybrid vehicle, power source braking includes engine braking based on engine pumping loss and regenerative braking by a regenerative load on an electric motor. Braking by a power source is useful in that braking can be performed without stepping from an accelerator pedal to a brake pedal. Therefore, if the braking at the deceleration intended by the driver can be realized by the power source brake, the operability of the vehicle is greatly improved.

[0005]

However, in the conventional hybrid vehicle, the acceleration and deceleration intended by the driver cannot be properly realized. The relationship between the torque and the braking force output from the power source and the acceleration and deceleration actually generated in the vehicle changes according to the state of the vehicle. For example, when the number of occupants increases and the weight of the vehicle increases, the acceleration decreases even if the torque output from the power source is constant. For this reason, in the conventional hybrid vehicle, the actual acceleration and deceleration sometimes deviate from the driver's sense.

Further, in the conventional hybrid vehicle, there is a problem that the acceleration and the deceleration cannot be adjusted in a sufficiently wide range. Such a problem was particularly remarkable during braking. Since the braking force by the engine brake is substantially determined according to the rotation speed, in the conventional hybrid vehicle, the deceleration can only be set within a range where the regenerative load of the electric motor can be changed. For this reason, there were cases where the deceleration intended by the driver could not be sufficiently obtained. In particular, the deceleration tends to be insufficient while the vehicle is running at high speed.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a hybrid vehicle capable of accurately running at a set acceleration and deceleration and a control method for realizing such running. With the goal. It is another object of the present invention to provide a hybrid vehicle and a control method capable of adjusting acceleration and deceleration in a wide range.

The deceleration during braking is synonymous with negative acceleration of the vehicle. Therefore, in the present specification, the term acceleration will be used in the following meaning including deceleration. When the term acceleration is used without including deceleration, it is specified as “positive acceleration”. When only negative acceleration is meant, the term “deceleration” is used.

[0009]

Means for Solving the Problems and Their Functions and Effects In order to solve at least a part of the above-mentioned problems, the present invention has the following configuration. The hybrid vehicle of the present invention has an axle coupled to a power source including an engine and an electric motor,
A hybrid vehicle capable of running and braking by the torque of the power source, input means for inputting a target acceleration of the vehicle, engine control means for operating the engine in an operating state determined based on the target acceleration, A gist comprising: detection means for detecting the acceleration of the vehicle; and motor control means for controlling the operation of the electric motor based on a deviation between the acceleration and the target acceleration, and converging the deviation within a predetermined range. I do.

According to such a hybrid vehicle, a desired acceleration can be accurately realized by performing so-called feedback control of the electric motor based on a deviation between the input target acceleration of the vehicle and the actual acceleration. Therefore, the operability of the hybrid vehicle can be greatly improved.

In a vehicle using only an engine as a power source, it is necessary to control the operation of the engine in order to perform acceleration at a target acceleration. However, control of the engine output torque and the like has relatively low accuracy and low response, so that it is difficult to achieve sufficient accuracy. On the other hand, the electric motor has a feature that the operating state can be controlled with high responsiveness and high accuracy. The present invention has been made in view of such features, by eliminating the deviation of the acceleration resulting from driving the engine in a predetermined driving state determined according to the target acceleration by controlling the electric motor,
Control with high precision can be realized.

From the above viewpoint, the control of the engine in the present invention means a control for driving the vehicle in a state necessary for running the vehicle within a range in which the target acceleration can be realized by controlling the electric motor. Such control can be realized by various methods. For example, the operation may be controlled based on the relationship between the target acceleration stored in advance and the engine speed and torque. Naturally, it is also possible to take into account not only the target acceleration but also the current running state of the vehicle. Further, the operation state of the engine may be feedback-controlled so that the deviation between the target acceleration and the actual acceleration falls within a predetermined range.

The detecting means of the present invention mainly means a means for detecting an acceleration generated as a result of operating the engine in a predetermined operating state. Of course, the acceleration may be detected prior to the control of the engine, and the electric motor may be controlled in consideration of the change in the operating state of the engine. In such a case, as a method of considering a change in the operating state of the engine, for example, a method of correcting a deviation between the actual acceleration and the target acceleration based on the change, and various methods used when setting the operating state of the electric motor are used. Various methods can be adopted, such as a method of correcting the gain of.

The present invention is applied to a hybrid vehicle in which a transmission capable of changing a plurality of speed ratios between the rotation speed of the power source and the rotation speed of the axle is interposed between the power source and the axle. You can also.

If the speed ratio of the transmission is also controlled based on the difference between the acceleration and the target acceleration, the speed ratio of the torque output to the axle can be changed in a wide range. Become. Therefore, according to such a hybrid vehicle, the acceleration and the deceleration input in a wide range can be realized.

When applied to such a hybrid vehicle,
Various modes are conceivable for the control method of the transmission gear ratio. For example, there is provided a transmission control unit that controls the transmission to switch the transmission ratio based on a deviation between the acceleration and the target acceleration. It may be a means for controlling the operation of the electric motor.

That is, the transmission ratio is feedback controlled. That is, if it is determined that the torque output to the axle is insufficient based on the difference between the acceleration and the target acceleration, the transmission is controlled to increase the gear ratio. Conversely, if it is determined that the output torque is excessive, the transmission is controlled so that the gear ratio becomes smaller. Further, the electric motor is controlled in consideration of the gear ratio of the transmission. In a vehicle without a transmission, the insufficient or excessive torque is eliminated by changing the operation of the electric motor, whereas in the hybrid vehicle, it is eliminated by changing the gear ratio and controlling the operating state of the electric motor. . As a result, according to the hybrid vehicle, it is possible to suppress a large change in the operation state of the electric motor, and to realize stable control.

In the above hybrid vehicle,
Although it is possible to apply a transmission that can change the gear ratio stepwise, it is more desirable to apply a mechanism that can change the gear ratio continuously. This makes it possible to more appropriately eliminate the insufficient or excessive torque by controlling the transmission.

The transmission may be controlled in the following manner. That is, a storage unit that stores a predetermined relationship between the target acceleration and the gear ratio, and the transmission is controlled to switch to a gear ratio determined based on the target acceleration according to the relationship. Transmission control means may be provided, and the motor control means may be means for controlling operation of the motor based on a deviation between the acceleration and the target acceleration and the gear ratio. That is, this is a mode in which the transmission is controlled in an open loop.

In the above hybrid vehicle, the gear ratio of the transmission is set to a predetermined value in accordance with the target acceleration, and the operation of the electric motor is feedback-controlled. Generally, control of the transmission gear ratio has relatively low responsiveness. Responsiveness required when performing open-loop control of the gear ratio to a predetermined value based on the target acceleration is also relatively low. Therefore, if the transmission is controlled by the open loop control, the hybrid vehicle can be controlled stably. Such control also has an advantage that the control of the transmission is simplified.

The relationship between the target acceleration and the speed ratio stores a speed ratio in a range in which the target acceleration can be realized by the torque from the power source. When the operating state of the engine can be estimated in advance according to the target acceleration, the relationship can be set in consideration of the operating state of the engine. Needless to say, this relationship may be such that the gear ratio is given in consideration of the vehicle speed and the like in addition to the target acceleration.

In the hybrid vehicle according to the present invention, the target acceleration may be a value obtained by calculating the target acceleration in accordance with the running state of the vehicle. It may be a means for inputting.

[0023] In this way, it is possible to realize a running that is not uncomfortable for the driver. The driver can travel in a desired state without frequently operating the accelerator, the brake, and the like. Therefore, the operability of the vehicle can be greatly improved. The target acceleration is calculated in accordance with the running state of the vehicle. There is a case where a target acceleration is calculated based on a deviation from an actual value.

Also, in the hybrid vehicle according to the present invention, execution instruction input means for inputting an instruction for executing control based on the target acceleration, and the input means, engine control means, It is preferable to include a detection unit and a permission unit that permits all operations of the motor control unit.

In such a hybrid vehicle, control for achieving the target acceleration is performed only when a predetermined instruction is input. When the driver inputs such an instruction, the driver can clearly recognize that traveling at a predetermined target acceleration is realized, so that it is possible to perform driving without feeling uncomfortable. In particular, when the driver inputs the target acceleration, in order to clearly recognize that traveling at the acceleration input by the driver is realized, avoid mistakes such as inadvertently changing the setting of the target acceleration. be able to.

Although the present invention is applicable to both acceleration and braking, the target acceleration is acceleration at the time of braking by the torque of the power source, and the engine control means applies a braking torque to the axle. It is preferable that the means is a means for operating the engine in a state where the engine can be operated.

In general, during driving of a vehicle, the driver often needs to adjust the acceleration with high accuracy during braking. Braking is often performed as necessary, for example, when it is desired to increase the distance between the vehicle and the vehicle in front or when it is necessary to stop the vehicle. In such a case, if braking is performed at a deceleration lower than the driver's intended deceleration, the driver needs to depress the brake pedal to use the wheel brake. Further, if braking is performed at a deceleration higher than the deceleration intended by the driver, large acceleration is required after braking. In any case, smooth running of the vehicle is hindered, and the usefulness of the power source brake is impaired. According to the present invention, since braking at a predetermined deceleration can be performed with high accuracy, such an adverse effect can be avoided. As a result, the usefulness of the power source brake can be improved, and the operability of the vehicle can be improved. The present invention can thus be applied particularly effectively during braking.

The present invention can be configured as a hybrid vehicle control method as described below. That is, a control method of a hybrid vehicle having an axle coupled to a power source including at least an engine and an electric motor, and capable of running and braking by the torque of the power source, comprising:
Inputting a target acceleration of the vehicle, (b) operating the engine in a driving state determined based on the target acceleration, (c) detecting an acceleration of the vehicle, and (d) detecting the acceleration of the vehicle. And controlling the operation of the electric motor based on a deviation from the target acceleration.

According to such a control method, the same operation as described above for the hybrid vehicle of the present invention can be performed.
The input target acceleration can be realized with high accuracy. As a result, the operability of the hybrid vehicle can be greatly improved. It should be noted that the control method can also include various additional elements described in the invention of the hybrid vehicle.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples. (1) Configuration of device: FIG. 1 is a schematic configuration diagram of a hybrid vehicle as an embodiment. The power sources of the hybrid vehicle of this embodiment are the engine 10 and the motor 20. As shown in the figure, the power system of the hybrid vehicle according to the present embodiment includes:
The engine 10, the motor 20, the torque converter 30, and the transmission 100 are connected in series from the upstream side. Specifically, motor 20 is coupled to crankshaft 12 of engine 10. The rotating shaft 13 of the motor 20 is connected to the torque converter 30. The output shaft 14 of the torque converter is connected to the transmission 100. The output shaft 15 of the transmission 100 is connected to an axle 17 via a differential gear 16.

The engine 10 is a normal gasoline engine. However, the engine 10 sets the opening / closing timing of an intake valve for sucking a mixture of gasoline and air into the cylinder and an exhaust valve for discharging exhaust gas after combustion from the cylinder relative to the vertical movement of the piston. It has an adjustable mechanism (hereinafter, this mechanism is called a VVT mechanism). Since the configuration of the VVT mechanism is well known, a detailed description is omitted here. Engine 10
The so-called pumping loss can be reduced by adjusting the opening / closing timing so that each valve closes with a delay with respect to the vertical movement of the piston. As a result,
It is possible to reduce a braking force by a so-called engine brake. Further, the torque to be output from the motor 20 when the engine 10 is motored can be reduced. When power is output by burning gasoline, V
The VT mechanism is controlled such that each valve opens and closes at a timing with the highest combustion efficiency according to the rotation speed of the engine 10.

The motor 20 is a three-phase synchronous motor,
A rotor 22 having a plurality of permanent magnets on an outer peripheral surface and a stator 24 around which a three-phase coil for forming a rotating magnetic field is wound. The motor 20 is driven to rotate by interaction between a magnetic field generated by a permanent magnet provided on the rotor 22 and a magnetic field formed by a three-phase coil of the stator 24. When the rotor 22 is rotated by an external force, an interaction between these magnetic fields generates an electromotive force at both ends of the three-phase coil. The motor 20 includes the rotor 2
It is also possible to apply a sine wave magnetized motor in which the magnetic flux density between the stator 2 and the stator 24 has a sine distribution in the circumferential direction. A magnetic motor was applied.

The stator 24 is electrically connected to a battery 50 via a drive circuit 40. The drive circuit 40 is a transistor inverter, and is provided with a plurality of transistors for each of the three phases of the motor 20 by using two sets, one on the source side and the other on the sink side. As illustrated, the drive circuit 40 is electrically connected to the control unit 70. When the control unit 70 performs PWM control of the on / off time of each transistor of the drive circuit 40, a pseudo three-phase alternating current using the battery 50 as a power supply flows through the three-phase coil of the stator 24, and a rotating magnetic field is formed. The motor 20 functions as an electric motor or a generator as described above by the rotating magnetic field.

The torque converter 30 is a known power transmission mechanism using a fluid. The input shaft of the torque converter 30, that is, the output shaft 13 of the motor 20, and the output shaft 14 of the torque converter 30 are not mechanically coupled,
They can rotate with each other slipping. Turbines each having a plurality of blades are provided at both ends, and the turbine of the output shaft 13 of the motor 20 and the turbine of the output shaft 14 of the torque converter 30 are assembled inside the torque converter in a state where they face each other. ing. The torque converter 30 has a closed structure, and transmission oil is sealed therein. This oil acts on each of the aforementioned turbines,
Power can be transmitted from one rotating shaft to the other rotating shaft. In addition, since both can rotate in a slipping state, it is possible to convert the power input from one of the rotating shafts into a rotating state having a different number of rotations and a different torque and transmit the converted power to the other rotating shaft.

The transmission 100 includes a plurality of gears, clutches, one-way clutches, brakes, and the like, and converts the torque and the number of revolutions of the output shaft 14 of the torque converter 30 by switching the speed ratio, thereby forming the output shaft 15. It is a mechanism that can transmit. FIG. 2 is an explanatory diagram showing the internal structure of the transmission 100. The transmission 100 of the present embodiment is mainly composed of an auxiliary transmission portion 110 (a portion on the left side of the broken line in the drawing) and a main transmission portion 120 (a portion on the right side of the broken line in the drawing). Thus, five forward speeds and one reverse speed can be realized.

The structure of the transmission 100 will be described in order from the rotating shaft 14 side. As shown in the figure, the power input from the rotating shaft 14 is transmitted to the rotating shaft 119 after being shifted at a predetermined gear ratio by a subtransmission unit 110 configured as an overdrive unit. The auxiliary transmission unit 110 is configured by a clutch C0, a one-way clutch F0, and a brake B0 centering on a single-pinion type first planetary gear 112. The first planetary gear 112 is a gear also referred to as a planetary gear, and includes three types of gears: a sun gear 114 that rotates at the center, a planetary pinion gear 115 that revolves while rotating around the sun gear, and a ring gear 118 that rotates around the outer periphery of the planetary pinion gear. It is composed of The planetary pinion gear 115 is supported by a rotating part called a planetary carrier 116.

In general, a planetary gear has such a property that when the rotational state of two of the three gears is determined, the rotational state of the remaining one gear is determined. The rotation state of each gear of the planetary gear is given by a calculation formula (1) well-known in mechanics. Ns = (1 + ρ) / ρ × Nc−Nr / ρ; Nc = ρ / (1 + ρ) × Ns + Nr / (1 + ρ); Nr = (1 + ρ) Nc−ρNs; Ts = Tc × ρ / (1 + ρ) = ρTr; Tr = Tc / (1 + ρ); ρ = number of teeth of sun gear / number of teeth of ring gear (1);

Here, Ns is the rotation speed of the sun gear; Ts is the torque of the sun gear; Nc is the rotation speed of the planetary carrier; Tc is the torque of the planetary carrier; Nr is the rotation speed of the ring gear;

In the auxiliary transmission section 110, the rotating shaft 14 corresponding to the input shaft of the transmission 100 is connected to the planetary carrier 116. A one-way clutch F0 and a clutch C0 are arranged in parallel between the planetary carrier 116 and the sun gear 114. The one-way clutch F0 is provided in a direction in which the sun gear 114 is engaged when the sun gear 114 rotates forward relative to the planetary carrier 116, that is, when the sun gear 114 rotates in the same direction as the input shaft 14 to the transmission.
The sun gear 114 is provided with a multi-disc brake B0 that can stop the rotation. A ring gear 118 corresponding to the output of the subtransmission unit 110 is connected to the rotation shaft 119. The rotation shaft 119 corresponds to an input shaft of the main transmission unit 120.

In the subtransmission unit 110 having such a configuration, the planetary carrier 116 and the sun gear 114 rotate integrally when the clutch C0 or the one-way clutch F0 is engaged. According to the equation (1) shown above, when the rotation speeds of the sun gear 114 and the planetary carrier 116 are equal, the rotation speed of the ring gear 118 is also equal to them. At this time, the rotation shaft 119 is the input shaft 1
The number of rotations is the same as 4. Also, when the rotation of the sun gear 114 is stopped by engaging the brake B0, the rotation speed Nr of the ring gear 118 is apparent as a result of substituting a value 0 for the rotation speed Ns of the sun gear 114 in the above-described equation (1).
Is higher than the rotation speed Nc of the planetary carrier 116. That is, the rotation of the rotating shaft 14 is accelerated and the rotating shaft 119 is rotated.
Is transmitted to As described above, the auxiliary transmission unit 110 is
The power input from 4 is applied to the rotating shaft 11 as it is.
9 and the role of increasing the speed can be selectively performed.

Next, the configuration of the main transmission section 120 will be described.
The main transmission section 120 includes three sets of planetary gears 130 and 14.
0,150. Also, clutches C1, C2,
One-way clutches F1, F2 and brakes B1-B
4 is provided. Each of the planetary gears is
Similarly to the first planetary gear 112 provided in the first embodiment, a sun gear, a planetary carrier, a planetary pinion gear, and a ring gear are provided. The three planetary gears 130, 140, 150 are connected as follows.

Sun gear 1 of second planetary gear 130
32 and the sun gear 142 of the third planetary gear 140 are integrally connected to each other.
2 can be coupled to the input shaft 119. On the rotation shaft to which these sun gears 132 and 142 are connected,
A brake B1 for stopping the rotation is provided. Further, a one-way clutch F1 is provided in a direction in which the rotation shaft is engaged when the rotation shaft reversely rotates. Further, a brake B for stopping rotation of the one-way clutch F1
2 are provided.

The planetary carrier 134 of the second planetary gear 130 is provided with a brake B capable of stopping its rotation.
3 are provided. The ring gear 136 of the second planetary gear 130 is connected to the planetary carrier 144 of the third planetary gear 140 and the fourth planetary gear 15.
0 and the planetary carrier 154. Furthermore, these three are coupled to the output shaft 15 of the transmission 100.

The ring gear 146 of the third planetary gear 140 is connected to the sun gear 15 of the fourth planetary gear 150.
2 and to the rotating shaft 122. The rotation shaft 122 is connected to the main transmission unit 12 via the clutch C1.
0 can be coupled to the input shaft 119. The ring gear 156 of the fourth planetary gear 150 is provided with a brake B4 for stopping the rotation thereof and a one-way clutch F2 in a direction in which the ring gear 156 is engaged when the ring gear 156 reversely rotates.

The above-described clutches C0 to C2 and brakes B0 to B4 provided in the transmission 100 are engaged and released by hydraulic pressure, respectively. Although not shown, each clutch and brake is provided with a hydraulic pipe for enabling such an operation, a solenoid valve for controlling hydraulic pressure, and the like. In the hybrid vehicle of the present embodiment,
The control unit 70 controls the operation of each clutch and brake by outputting control signals to these solenoid valves and the like.

The transmission 100 of this embodiment has a clutch C0
C5 and the engagement and disengagement of the brakes B0 to B4 make it possible to set five forward speeds and one reverse speed. Also, so-called parking and neutral states can be realized. FIG. 3 is an explanatory diagram showing the relationship between the engagement state of each clutch, brake, and one-way clutch and the shift speed. In this figure, a mark ○ means that the clutch or the like is engaged, a mark 係 合 means that the clutch is engaged during power source braking,
The mark means that it engages but does not affect power transmission. The power source brake refers to braking by the engine 10 and the motor 20. The one-way clutch F
The engagement states of 0 to F2 are not based on the control signal of the control unit 70 but based on the rotation direction of each gear.

As shown in FIG. 3, in the case of parking (P) and neutral (N), the clutch C0 and the one-way clutch F0 are engaged. Since both the clutch C2 and the clutch C1 are in the disengaged state, the main transmission 1
No power is transmitted downstream from the 20 input shafts 119.

In the case of the first speed (1st), the clutch C
0, C1 and one-way clutches F0, F2 are engaged. When the engine brake is applied, the brake B4 is further engaged. In this state, the transmission 100
Is equivalent to a state in which the input shaft 14 of the fourth planetary gear 150 is directly connected to the sun gear 152 of the fourth planetary gear 150.
5 is transmitted. The ring gear 156 is restrained so as not to reverse by the action of the one-way clutch F2, and the number of rotations is practically zero. Under such conditions, according to the above-described equation (1), the rotation speed Nin and the torque Tin of the input shaft 14, the rotation speed Nout of the output shaft 15, and the torque Tou
The relationship with t is given by the following equation (2).

Nout = Nin / k1; Tout = k1 × Tin k1 = (1 + ρ4) / ρ4; ρ4 is the speed ratio of the fourth planetary gear 150 (2);

In the case of the second speed (2nd), the clutch C
1. The brake B3 and the one-way clutch F0 are engaged. When the engine brake is applied, the clutch C0 is further engaged. In this state, the transmission 100
Is equivalent to a state where the input shaft 14 is directly connected to the sun gear 152 of the fourth planetary gear 150 and the ring gear 146 of the third planetary gear 140. On the other hand, the planetary carrier 134 of the second planetary gear 130 is in a fixed state. Second planetary gear 130 and third planetary gear
, The rotational speeds of the sun gears 132 and 142 are equal. Further, the rotation speeds of the ring gear 136 and the planetary carrier 144 are equal.
Under these conditions, in light of equation (1) described above,
The rotation state of the planetary gears 130 and 140 is uniquely determined. Rotational speed Nin of input shaft 14, torque Tin
And the relationship between the rotation speed Nout of the output shaft 15 and the torque Tout are given by the following equation (3). The rotation speed Nout of the output shaft 15 becomes higher than the rotation speed of the first speed (1st),
The torque Tout is lower than the first speed (1st) torque.

Nout = Nin / k2; Tout = k2 × Tink2 = {ρ2 (1 + ρ3) + ρ3} / ρ2; ρ2 is the speed ratio of the second planetary gear 130; ρ3 is the speed ratio of the third planetary gear 140 (3);

In the case of the third speed (3rd), the clutch C
0, C1, brake B2, one-way clutch F0, F
1 engage. When the engine brake is applied, the brake B1 is further engaged. In this state, the input shaft 14 of the transmission 100 is connected to the fourth planetary gear 150
Of the third planetary gear 140 and the ring gear 146 of the third planetary gear 140. On the other hand, the sun gears 132 and 142 of the second and third planetary gears 130 and 140 are in a state in which reverse rotation is prohibited by the action of the brake B2 and the one-way clutch F1, and the rotation speed is practically zero. Under these conditions, the second speed (2
As in the case of nd), according to the above-described equation (1), the rotational state of the planetary gears 130 and 140 is uniquely determined, and the rotational speed of the output shaft 15 is also uniquely determined. The relationship between the rotation speed Nin and the torque Tin of the input shaft 14 and the rotation speed Nout and the torque Tout of the output shaft 15 is as follows.
It is given by the following equation (4). Rotation speed Nout of output shaft 15
Becomes higher than the rotation speed of the second speed (2nd), and the torque T
out becomes lower than the torque of the second speed (2nd).

Nout = Nin / k3; Tout = k3 × Tin k3 = 1 + ρ3 (4);

In the case of the fourth speed (4th), the clutch C
0 to C2 and the one-way clutch F0 are engaged. The brake B2 is also engaged at the same time, but has nothing to do with the transmission of power. In this state, since the clutches C1 and C2 are simultaneously engaged, the input shaft 14 is connected to the second planetary gear 130.
, The sun gear 142 and the ring gear 146 of the third planetary gear 140, and the sun gear 152 of the fourth planetary gear 150.
As a result, the third planetary gear 140 rotates integrally with the input shaft 14 at the same rotation speed. Therefore, the output shaft 15 also integrally rotates at the same rotation speed as the input shaft 14. Therefore, in the fourth speed (4th), the output shaft 15 rotates at a higher rotation speed than in the third speed (3rd). That is, the rotation speed Nin and the torque Tin of the input shaft 14 and the rotation speed Nou of the output shaft 15
The relationship between t and the torque Tout is given by the following equation (5). The rotation speed Nout of the output shaft 15 is higher than the rotation speed of the third speed (3rd), and the torque Tout is increased to the third speed (3rd).
The torque becomes lower than d).

Nout = Nin / k4; Tout = k4 × Tin k4 = 1 (5);

In the case of the fifth speed (5th), the clutch C
1, C2 and brake B0 are engaged. The brake B2 is also engaged, but has nothing to do with power transmission. In this state, the clutch C0 is disengaged, and the rotation speed is increased by the subtransmission unit 110. That is, the input shaft 1 of the transmission 100
The rotation speed of the input shaft 11 of the main transmission unit 120 is increased
9 is transmitted. On the other hand, since the clutches C1 and C2 are simultaneously engaged, as in the case of the fourth speed (4th), the input shaft 1
19 and the output shaft 15 rotate at the same rotation speed. According to the above-described equation (1), the input shaft 14 of the subtransmission unit 110 is
And the rotation speed and torque of the output shaft 119, and the rotation speed and torque of the output shaft 15 can be obtained. The relationship between the rotation speed Nin and the torque Tin of the input shaft 14 and the rotation speed Nout and the torque Tout of the output shaft 15 is as follows.
It is given by the following equation (6). Rotation speed Nout of output shaft 15
Becomes higher than the rotation speed of the fourth speed (4th), and the torque T
out becomes lower than the torque of the fourth speed (4th).

Nout = Nin / k5; Tout = k5 × Tin k5 = 1 / (1 + ρ1) ρ1 is the speed ratio of the first planetary gear 112 (6);

In the case of reverse (R), the clutch C
2. The brakes B0 and B4 are engaged. At this time, the rotation speed of the input shaft 14 is increased by the
Is connected directly to the sun gear 132 of the planetary gear 130 and the sun gear 142 of the third planetary gear 140. As described above, the rotation speeds of the ring gear 136 and the planetary carriers 144 and 154 are equal. The rotation speeds of the ring gear 146 and the sun gear 152 also become equal.
Also, the ring gear 156 of the fourth planetary gear 150
Becomes zero due to the action of the brake B4. Under these conditions, according to the above-described equation (1), the rotational state of the planetary gears 130, 140, and 150 is uniquely determined. At this time, the output shaft 15 rotates in the negative direction,
Reverse is possible.

As described above, the transmission 1 of this embodiment
In the case of 00, five forward gears and one reverse gear can be realized. The power input from the input shaft 14 is output from the output shaft 15 as power having different rotation speed and torque.
The power output is from the first gear (1st) to the fifth gear (5t
The rotation speed increases in the order of h), and the torque decreases. This is the same when a negative torque, that is, a braking force is applied to the input shaft 14. The variables k1 to k5 in the above equations (2) to (6) represent the gear ratios of the respective gears. When a constant braking force is applied to the input shaft 14 by the engine 10 and the motor 20, the first speed (1st)
, The braking force applied to the output shaft 15 decreases in the order of the fifth speed (5th). As the transmission 100, various well-known configurations other than the configuration applied in the present embodiment can be applied. Either one where the shift speed is smaller than or larger than the fifth forward speed is applicable.

The gear position of the transmission 100 is determined by the control unit 7
0 is set according to the vehicle speed or the like. The driver can manually operate a shift lever provided in the vehicle to select a shift position, thereby changing a range of a shift speed to be used. FIG. 4 is an explanatory diagram showing the operation unit 160 of the shift position in the hybrid vehicle of the present embodiment. The operation unit 160 is provided on the floor next to the driver's seat in the vehicle along the front-rear direction of the vehicle.

As shown, a shift lever 162 is provided as an operation unit. The driver uses the shift lever 162
Can be selected in various directions by sliding back and forth along the groove in the figure. The shift positions are parking (P), reverse (R), neutral (N), drive position (D), M position (M), four positions (4), three from the front.
Position (3), position (2), and low position (L) are arranged in this order.

The parking (P), the reverse (R), and the neutral (N) respectively correspond to the engaged state shown in FIG. The drive position (D) means selection of a mode in which the vehicle travels using the first speed (1st) to the fifth speed (5th) shown in FIG. Below, 4 position (4) up to 4th speed (4th), 3 position (3) up to 3rd speed (3rd), 2 position (2) up to 2nd speed (2nd) and low position (L) This means selection of a mode in which the vehicle travels using only the first speed (1st). The M position is a shift position where the driver manually switches the gear position. The manual gear changeover is performed not by the shift lever 162 but by a switch provided on the steering wheel, as described later.

In the hybrid vehicle of this embodiment, the driver can arbitrarily set the deceleration by the power source brake, as described later. The operation unit 160 for selecting the shift position is also provided with a mechanism for setting the deceleration.

As shown in FIG. 4, the shift lever 162 in the hybrid vehicle according to the present embodiment can slide forward and backward to select a shift position, and can also slide leftward in the drive (D) position. It is. The position selected in this manner is called a B position. The operation section 160 is provided with a slide knob 161 in addition to the shift lever 162.
The driver can continuously change the deceleration of the vehicle by sliding the slide knob 161 back and forth. In this embodiment, when the slide knob 161 is slid forward, the deceleration increases, and when it is slid backward, the deceleration decreases. The operation by the slide knob 161 is valid when the B position is selected.

The operation unit 160 includes a sensor for detecting a shift position and a shift lever 162 inside.
And a sensor for detecting the amount of operation of the slide knob 161 that is turned on when is at the B position. The signals of these sensors and switches are transmitted to the control unit 70 as described later, and are used for various controls of the vehicle.

A mechanism for manually switching the gear position will be described. FIG. 5 is an explanatory diagram illustrating an operation unit provided on the steering wheel. FIG. 5A shows the steering 16.
FIG. 4 shows a side 4 facing the driver, that is, a state viewed from the front. As shown, DOWN switches 166L and 166R are provided on the spokes of the steering 164. The DOWN switches 166L and 166R are used to switch the gear to a side where the gear ratio increases. Each time the driver presses the DOWN switch 166L, 166R, the shift speed is switched one by one toward the first speed (1st). In the present embodiment, the two switches provided on the front surface are unified to have the same function so that an appropriate operation can be performed without confusion even when the steering wheel is rotated.

FIG. 5B shows a state in which the steering 164 is viewed from the back. As shown in the figure, the U switch is located at a position almost
P switches 168L and 168R are provided. UP
The switch is used to switch the gear position to the side where the gear ratio becomes smaller. When the driver turns on the UP switch 168L,
Each time 168R is pressed, the gear position is switched one by one toward the fifth speed (5th). DOWN switch 166
For the same reason as L, 166R, both switches are unified to have the same function.

The switches 166L, 166
R, 168L, and 168R are valid only when the shift lever 162 is at the M position (see FIG. 4). With this configuration, the driver can turn the steering wheel 1
By operating these switches unintentionally when operating the gear 64, it is possible to prevent the gear from being changed.

The operation unit 160 is further provided with a snow mode switch 163. The snow mode switch 163 is operated by the driver when the road surface has a low coefficient of friction such as a snowy road and slips easily.
When the snow mode switch 163 is turned on, the upper limit value of the target deceleration is suppressed to a predetermined value or less, as described later. If the vehicle is decelerated at a large deceleration while traveling on a road surface having a low friction coefficient, slipping may occur. When the snow mode switch 163 is on, the deceleration is suppressed to a predetermined value or less, so that a slip can be avoided. of course,
When the snow mode switch 163 is turned on, it is possible to change the deceleration within a range where slip does not occur. The operation unit for selecting the shift position and setting the target deceleration can employ various configurations other than the configuration shown in the present embodiment (FIG. 4).

The deceleration setting described above is displayed on the dashboard in the vehicle. FIG. 6 is an explanatory diagram illustrating an instrument panel of the hybrid vehicle according to the present embodiment. This instrument panel
Like a normal vehicle, it is installed in front of the driver. The instrument panel is provided with a fuel gauge 202 and a speedometer 204 on the left side as viewed from the driver, and an engine water temperature gauge 20 on the right side.
8. An engine tachometer 206 is provided. A shift position indicator 220 for displaying a shift position is provided at the center, and direction indicator indicators 210L and 210R are provided on the left and right sides thereof. These are display units equivalent to a normal vehicle. In the hybrid vehicle of this embodiment, an M position indicator 222 is provided above the shift position indicator 220 in addition to these display units. Further, a deceleration indicator 224 for displaying the set deceleration is provided on the right side of the M position indicator 222.

The M position indicator 222 lights when the shift lever is at the M position. As shown, the deceleration indicator 224 includes a vehicle symbol and a backward arrow (a right arrow in FIG. 6). When the vehicle symbol is lit when in the B position and the driver operates the slide knob 161 to set the deceleration, the length of the backward arrow (the right arrow in FIG. 6) increases or decreases, and the setting result is obtained. Is intuitively represented. As described later, the hybrid vehicle of the present embodiment
The deceleration set based on various conditions may be suppressed. When the suppression is performed, the deceleration indicator 224 performs a display in an unusual manner such as a blinking display to notify the driver of the suppression of the deceleration.

In the hybrid vehicle of the present embodiment, the engine 10, the motor 20, the torque converter 30, the transmission 1
1 is controlled by the control unit 70 (see FIG. 1).
reference). The control unit 70 includes a CPU, a RAM,
This is a one-chip microcomputer including a ROM and the like, and a CPU performs various control processes described later according to a program recorded in the ROM. Various input / output signals are connected to the control unit 70 to realize such control. FIG. 1 shows an operation unit 1 as a representative example.
60 and the acceleration sensor 170 are shown. FIG. 7 is an explanatory diagram showing connection of input / output signals to the control unit 70. A signal input to the control unit 70 is shown on the left side of the drawing, and a signal output from the control unit 70 is shown on the right side.

The signals input to the control unit 70 are signals from various switches and sensors. Such a signal includes, for example, a hybrid cancel switch that instructs operation using only the engine 10 as a power source, an acceleration sensor that detects the acceleration of the vehicle, the number of revolutions of the engine 10,
The water temperature of the engine 10, the ignition switch, the remaining capacity SOC of the battery 50, the crank position of the engine 10,
Defogger on / off, air conditioner operating status, vehicle speed,
The oil temperature and shift position of the torque converter 30 (FIG. 4)
), Side brake ON / OFF, foot brake depression amount, temperature of catalyst for purifying exhaust of engine 10, accelerator opening, auto cruise switch ON / OFF, M position switch ON / OFF (see FIG. 4) ),
A DOWN switch and an UP switch for switching gears, a snow mode switch for instructing a running mode on a low friction coefficient road surface such as a turbine speed of a turbocharger and a snowy road,
There is a fuel lid signal from the fuel gauge, a slide knob signal for instructing the setting of deceleration, and the like.

The signal output from the control unit 70 is
These are signals for controlling the engine 10, the motor 20, the torque convertor 30, the transmission 100, and the like. Such signals include, for example, an ignition signal for controlling the ignition timing of the engine 10, a fuel injection signal for controlling the fuel injection, a starter signal for starting the engine 10, and switching of the drive circuit 40 to operate the motor 20. MG control signal to control,
A transmission control signal for switching the gear position of the transmission 100, an AT solenoid signal and an AT line pressure control solenoid signal for controlling a hydraulic pressure of the transmission 100, a signal for controlling an actuator of an antilock brake system (ABS), a driving force Drive power source indicator signal indicating the power source, air conditioner control signal, control signal for preventing various alarm sounds, control signal of electronic throttle valve of engine 10, snow mode indicator signal indicating selection of snow mode, engine There are a VVT signal for controlling the opening / closing timing of the ten intake valves and exhaust valves, a system indicator signal for displaying the operating state of the vehicle, and a set deceleration indicator signal for displaying the set deceleration.

(2) General Operation: Next, the general operation of the hybrid vehicle of this embodiment will be described. Figure 1
As described above, the hybrid vehicle of the present embodiment includes the engine 10 and the motor 20 as power sources. The control unit 70 uses both of them according to the traveling state of the vehicle, that is, the vehicle speed and the torque. The use of both is set in advance as a map, and the ROM in the control unit 70 is used.
Is stored in

FIG. 8 is an explanatory diagram showing the relationship between the running state of the vehicle and the power source. The curve LIM in the figure indicates the limit of the area in which the vehicle can travel. A region MG in the figure is a region where the vehicle runs with the motor 20 as the power source, and a region EG is a region where the vehicle runs with the engine 10 as the power source. Hereinafter, the former is referred to as EV traveling, and the latter is referred to as normal traveling. According to the configuration of FIG.
Although it is possible to run with both of the power sources 0 as the power source, such a running region is not provided in the present embodiment.

As shown in the figure, the hybrid vehicle according to the present embodiment starts by EV running. As described above (see FIG. 1), the hybrid vehicle of the present embodiment has the engine 1
0 and the motor 20 are configured to rotate integrally. Therefore, the engine 10 is also rotating during the EV traveling. However, the motoring is being performed without performing fuel injection and ignition. As described above, the engine 10 includes the VVT mechanism. Control unit 7
0 indicates the opening / closing timing of the intake valve and the exhaust valve by controlling the VVT mechanism in order to reduce the load applied to the motor 20 during EV running and to use the power output from the motor 20 effectively for running the vehicle. Delay.

Control unit 70 starts engine 10 when the vehicle started by EV running reaches a running state near the boundary between region MG and region EG in the map of FIG. Since the engine 10 has already been rotated at a predetermined rotation speed by the motor 20, the control unit 70 injects fuel into the engine 10 at a predetermined timing and ignites it.
Further, the VVT mechanism is controlled to change the opening / closing timing of the intake valve and the exhaust valve to a timing suitable for the operation of the engine 10.

After the engine 10 is started in this way, the vehicle runs in the region EG using only the engine 10 as a power source. When traveling in such an area is started, the control unit 70 shuts down all the transistors of the drive circuit 40. As a result, the motor 20 simply turns idle.

The control unit 70 performs the control of switching the power source in accordance with the running state of the vehicle as described above, and also performs the process of switching the gear position of the transmission 100 in a shift position other than the M position. The switching of the shift speed is performed based on a map set in advance in the running state of the vehicle, similarly to the switching of the power source. FIG. 9 is a map showing the relationship between the gear position of transmission 100 and the traveling state of the vehicle. As shown in this map, the control unit 70
The gear change is performed such that the gear ratio decreases as the vehicle speed increases.

This switching is restricted by the shift position. In the drive position (D), as shown in FIG. 9, the vehicle travels using the speed up to the fifth speed (5th). In the four positions, the vehicle travels using gears up to the fourth speed (4th). In this case, 5th in FIG.
, The fourth speed (4th) is used. In addition to the switching based on this map, the shift speed is switched by so-called kick down, in which the driver shifts the shift speed to a higher one-speed ratio by rapidly depressing an accelerator pedal. These switching controls are:
This is the same as a known vehicle that uses only an engine as a power source and includes an automatic transmission. In the present embodiment, the same switching is performed when the vehicle is traveling in the EV mode (the area MG). The relationship between the shift speed and the running state of the vehicle can be variously set according to the speed ratio of the transmission 100, in addition to the relationship shown in FIG.

FIGS. 8 and 9 show maps in the case where the EV traveling and the normal traveling are selectively used according to the traveling state of the vehicle. The control unit 70 of the present embodiment is also provided with a map in a case where all traveling states are performed in normal traveling.
These maps are obtained by removing the EV traveling region (region MG) in FIGS. 8 and 9. In order to perform the EV traveling, it is necessary that a certain amount of electric power is stored in the battery 50. Therefore, the control unit 7
0 switches the map in accordance with the state of charge of the battery 50 to execute vehicle control. That is, when the remaining capacity SOC of the battery 50 is equal to or more than the predetermined value, the operation is performed by selectively using the EV traveling and the normal traveling based on FIGS. 8 and 9. When the state of charge SOC of the battery 50 is smaller than a predetermined value, the vehicle is driven in normal traveling using only the engine 10 as a power source even during starting and traveling at a low speed. Use of the two maps is repeatedly determined at predetermined intervals. Therefore, even when the remaining capacity SOC is equal to or more than the predetermined value and the vehicle starts to start in EV traveling, if the remaining capacity SOC becomes smaller than the predetermined value as a result of the power consumption after the start, the running state of the vehicle falls within the area MG. Even if there is, it can be switched to normal running.

Next, braking of the hybrid vehicle of this embodiment will be described. The hybrid vehicle according to the present embodiment can be braked by two types of brakes: a wheel brake added by depressing a brake pedal, and a power source brake by load torque from the engine 10 and the motor 20. The braking by the power source brake is performed when the accelerator pedal is depressed. The target deceleration by the power source brake is set to decrease as the vehicle speed decreases, and the power source brake is controlled to decrease as the vehicle speed decreases. When the brake pedal is depressed, a braking force consisting of the sum of the power source brake and the wheel brake is applied to the vehicle.

In the hybrid vehicle of this embodiment, the driver can set the deceleration by the power source brake by operating the slide knob 161 described above. That is, when the slide knob 161 is moved to the side where the deceleration increases, the power source brake continuously increases. Moving to the decreasing side, the power source brake is continuously weakened.

In the hybrid vehicle according to the present embodiment, the deceleration of the power source brake is changed by controlling both the switching of the shift speed of the transmission 100 and the braking force by the motor 20 in combination. FIG. 10 is an explanatory diagram showing a map of a combination of the vehicle speed, the deceleration, and the shift speed in the hybrid vehicle of the present embodiment. In FIG. 10, the deceleration is indicated by an absolute value. Slide knob 161
By the operation of, the deceleration of the vehicle is changed from the straight line BL to the straight line BL in FIG.
It changes stepwise within the range of BU.

The deceleration by the power source brake is
By controlling the torque of 0, it can be changed within a certain range. Further, by switching the gear position of the transmission 100, the ratio between the torque of the power source and the torque output to the axle 17 can be changed, so that the deceleration of the vehicle can be changed according to the gear position. . As a result, when the gear is in the second speed (2nd), by controlling the torque of the motor 20, a deceleration in the range indicated by the short broken line in FIG. 10 can be achieved. 3rd speed (3rd)
, The deceleration in the range indicated by the solid line in FIG. 10 can be achieved. When the vehicle is in the fourth speed (4th), the deceleration in the range indicated by the one-dot chain line in FIG. 10 can be achieved. When the vehicle is in the fifth speed (5th), FIG.
A deceleration in the range indicated by the long broken line in 0 can be achieved.

The control unit 70 selects a gear that realizes the deceleration set according to the map of FIG. 10 and performs braking. For example, when the deceleration is set to the straight line BL in FIG. 10, in a region where the vehicle speed is higher than the value VC, the fifth
Braking is performed at the speed (5th), and in the region where the vehicle speed is lower than the value VC, the gear is switched to the fourth speed (4th) to perform braking. In such a region, the desired deceleration cannot be realized at the fifth speed (5th). In the present embodiment, the ranges of the deceleration realized at each shift speed are set to overlap. In a region where the vehicle speed is higher than the value VC, the deceleration corresponding to the straight line BL can be realized in both the fourth speed (4th) and the fifth speed (5th). Therefore, in such a region, the control unit 70 selects one of the fourth speed (4th) and the fifth speed (5th), based on various conditions, and performs a braking operation by selecting a gear that is more suitable for braking.

The setting of the shift speed in this embodiment will be described in more detail. FIG. 11 is an explanatory diagram showing the relationship between the deceleration and the shift speed at a certain vehicle speed Vs. This corresponds to the relationship between the deceleration and the shift speed along the straight line Vs in FIG. As shown in FIG. 11, the section D1 where the deceleration is relatively small.
In this case, deceleration is realized only in the fifth speed (5th). In the section D2 where the deceleration is larger than the fifth speed (5t
h) and the fourth speed (4th) achieves deceleration. Similarly, as the deceleration sequentially increases, only the fourth speed (4th) in the section D3, the third speed (3rd) or the fourth speed (4th) in the section D4, and the third speed (3rd) in the section D5.
Only in the section D6, the second speed (2nd) or the third speed (3
rd), in the section D7, each deceleration is realized only in the second speed (2nd). Here, the second speed (2n
Although the map using d) is shown, the first speed (1st)
Alternatively, the braking may be performed by using.

The reason why the decelerations at the respective gears overlap will be described. FIG. 12 is an explanatory diagram showing deceleration at the second speed (2nd). The broken line TL in the figure indicates the lower limit of the deceleration realized in the second speed (2nd), and the broken line TU
Indicates the upper limit. The straight line TE indicates the deceleration realized only by the engine brake by the engine 10.
In the hybrid vehicle of the present embodiment, it is possible to change the deceleration by the engine brake by controlling the VVT mechanism. However, such control has low response and accuracy. Therefore, in the present embodiment, when braking, V
Not controlling the VT mechanism. As a result, as shown in FIG. 12, the deceleration due to the engine brake is a value uniquely determined according to the vehicle speed.

In the present embodiment, the deceleration is changed by controlling the torque by the motor 20. FIG.
In the hatched region Bg, the motor 20 performs a so-called regenerative operation, and a braking force is also applied to the motor 20 to realize a deceleration larger than the deceleration due to the engine brake. The other area Bp, that is, the straight line T
In the region between E and the broken line TL, the motor 20 is driven in a power mode, and a driving force is output from the motor 20, thereby achieving a deceleration lower than that of the engine brake.

FIG. 13 is an explanatory diagram schematically showing the relationship between the braking torque when the motor 20 performs the regenerative operation and the braking torque when the motor 20 performs the power running operation. On the left side of the figure, the braking torque (state in the region Bp) when the motor 20 is operated in power running is shown. The braking torque by the engine brake is indicated by a belt BE in the figure. Region Bp
Then, the motor 20 outputs the driving force indicated by the band BM in the direction opposite to the braking torque by the engine brake.
Since a braking torque consisting of the sum of the two is output to the axle 17, a braking torque lower than the braking torque BE by the engine brake is output as shown by hatching in the figure.

On the right side of the figure, the braking torque (state in the region Bg) when the motor 20 performs the regenerative operation is shown. The braking torque by the engine brake is indicated by a band BE having the same size as that in the region Bp. Area B
At p, the motor 20 outputs the braking torque indicated by the band BM in the same direction as the braking torque by the engine brake. Since a braking torque consisting of the sum of the two is output to the axle 17, a braking torque larger than the braking torque BE by the engine brake is output as shown by hatching in the figure.

As described above, the hybrid vehicle of the present embodiment realizes a larger deceleration and a lower deceleration than the deceleration by the engine brake by switching the operation state of the motor 20 between the regenerative operation and the power running operation. .
Then, for example, the region of the deceleration realized by the power running operation at the gear stage on the side of the higher gear ratio and the region of the deceleration realized by the regenerative operation at the gear stage of the lower gear ratio overlap each other. The map of FIG. 10 is set. For example, an area of braking by power running at the second speed (2nd) and an area of braking by regenerative operation at the third speed (3rd) are overlapped.

By setting in this manner, braking can be performed in a mode suitable for the remaining capacity SOC of the battery 50. For example, when the battery 50 is in a state where it can be further charged, a gear position with a smaller gear ratio is selected so that a desired deceleration can be obtained by the regenerative operation of the motor 20. When the battery 50 is almost fully charged,
The gear position with the larger gear ratio is selected so that the desired deceleration is obtained by the power running operation of the motor 20. In the present embodiment, as described above, the ranges of the deceleration by the two shift speeds are set in an overlapping manner, so that the battery 5
The desired deceleration can be realized regardless of the remaining capacity SOC of zero.

Of course, these settings are merely examples, and the settings may be made so that the decelerations realized by the respective gears do not overlap. Further, the setting may be such that not all the shift speeds have an area overlapping each other as in the map of FIG. 10, but only some of the shift speeds have an overlapping area.

As described above, in this embodiment, braking at a deceleration according to the driver's setting is realized. However, such control is performed at the B position described above (hereinafter, such braking is referred to as B position braking). When the shift lever is not at the B position, braking is performed at a preset deceleration. When the vehicle is at the drive position (D), braking is performed at a preset deceleration within a range achievable using the speed up to the fifth speed (5th) on the map shown in FIG. . Also in the case of the four positions (4) to L position (L), braking is performed at a deceleration set within a range that can be realized in a shift speed usable in each shift position. In the M position, braking is performed at a deceleration that can be realized using only the gear selected by the driver. In the case other than B position,
The braking force of the motor 20 is also a regenerative operation that applies a constant load.

(3) Operation control processing: In the hybrid vehicle of the present embodiment, the control unit 70 controls the engine 10, the motor 20, and the like to enable the above-described traveling. Hereinafter, the details of the deceleration control will be described focusing on the driving at the time of braking characteristic of the hybrid vehicle of the present embodiment.

FIG. 14 is a flowchart of a deceleration control processing routine. This processing is performed by the CP of the control unit 70.
U is a process executed in a predetermined cycle. When this process is started, the CPU first performs a deceleration setting process (step S100). This process is a process for setting the deceleration to be realized based on the operation of the slide knob 161. The contents of the deceleration setting process will be described with reference to FIG.

FIG. 15 is a flowchart of a deceleration setting processing routine. When this process is started, the CPU inputs a switch signal (step S102). The signals input here are the signals of the slide knob, the shift position, and the snow mode switch among the various signals shown in FIG. Of course, other signals may be input together.

On the basis of the input signal, the CPU
Determines whether the B position has been selected (step S104). As described above, the hybrid vehicle of this embodiment can change the deceleration setting only when the B position is selected. Therefore, when it is determined that the B position has not been selected, the CPU turns off the display of the deceleration indicator 224 (step S106), and ends the deceleration setting processing routine. Even when the B position is not selected, only the setting of the deceleration may be enabled. In such a case, the determination in step S104 may be omitted.

If it is determined that the B position has been selected, the CPU determines whether or not the switch of the slide knob 161 has failed (step S110).
The failure can be determined by various methods. For example, when the switch is in poor contact, so-called chattering occurs, and the detection result of the operation amount of the slide knob 161 fluctuates very frequently and is detected. If a change equal to or greater than a predetermined value is detected, it can be determined that the switch has failed. A switch failure can be determined by various other methods.

When a switch failure is detected, the CPU cancels the setting of the target deceleration in order to avoid setting the deceleration unintended by the driver (step S).
115). Processing that does not change the setting of the target deceleration may be performed. In the present embodiment, it is assumed that the switch is broken while the driver is correcting the deceleration set to a value that does not conform to the driver's intention. It is assumed that the deceleration is set to a value corresponding to the case where the deceleration is performed. After releasing the setting of the target deceleration in this way, the CPU performs a failure display for notifying the driver of the failure of the switch (step S12).
0). Various methods can be used for the failure display. In this embodiment, the alarm sounds and the deceleration indicator 224 (see FIG. 6) blinks. These notifications are realized by outputting signals corresponding to the alarm sound signal and the system indicator signal shown in FIG. If the switch has failed, the CPU executes the above processing and ends the deceleration setting processing routine.

If it is determined in step S110 that the switch has not failed, the CPU sets the deceleration according to the operation amount of the slide knob 161 (step S110).
125). As described above, the deceleration is continuously changed in the range of the straight lines BU to BL in the map of FIG.

When the target deceleration is set in this way, the CPU determines whether or not the set deceleration is within the reject range (step S130). In the present embodiment, the ON / OFF of the snow mode switch 163 (see FIG. 6)
The upper limit of the deceleration is changed according to the off. The snow mode switch 163 is a switch operated by a driver when the vehicle is running on a road surface having a low friction coefficient such as a snowy road. If you apply sudden braking while driving on a road surface with a low friction coefficient,
The vehicle may slip. When the driver turns on the snow mode switch 163, the upper limit value of the deceleration is suppressed to such an extent that the slip of the vehicle can be avoided.

If the set deceleration exceeds the above upper limit, it is determined that the deceleration is within the reject range. If it is determined that the deceleration is within the reject range, the CPU
Suppresses the set deceleration to an allowable upper limit (step S135). In addition, a process for notifying the driver that the setting of the target deceleration has been suppressed is performed (step S140). In this embodiment, the deceleration indicator 224 blinks for about one second. In addition, a warning sound is emitted in conjunction with this. These notifications are realized by outputting appropriate signals for the alarm sound and the control signal of the set deceleration indicator shown in FIG. If it is determined in step S130 that the set deceleration is not within the reject range, these processes are skipped. When the deceleration is set by the above processing, the CPU displays the result on the deceleration indicator 224 (step S145), and ends the deceleration setting processing routine.

When the deceleration setting processing is completed, the CPU returns to the deceleration control processing routine (FIG. 14), and determines whether or not the accelerator pedal is off as a criterion of whether or not to perform braking by the power source brake. (Step S20)
0). This determination is made based on the input signal of the accelerator opening (see FIG. 7). When the accelerator pedal is not turned off, the CPU does not perform the braking by the power source brake, so the CPU ends the deceleration control processing routine without performing any processing.

If the accelerator pedal is off, the CPU changes the operating state of the engine to idle (step S250), and executes a gear position switching process (step S300). FIG. 16 is a flowchart of a gear shift processing routine. In this process, the CP
U is the switch signal, the vehicle speed, the remaining capacity S of the battery 50 first.
An OC is input (step S302). Here, the input switch signal is an input of the M position switch, the UP switch, and the DOWN switch.

Next, the CPU determines whether or not the M position is selected based on the ON / OFF of the M position switch (step S304). If the M position has been selected, the M position indicator 222 (see FIG. 6) is turned on (step S310).
Then, as described below, a process for switching to the gear position manually selected by the driver is executed.

First, the CPU determines whether or not the UP switch is turned on (step S312). If the UP switch is on, the speed is increased by one (step S314). Increasing the speed means that the speed is switched by one step toward the fifth speed (5th). However, in the present embodiment, since the fifth speed (5th) is the highest gear, this processing is performed in the range up to the fifth speed (5th). When the fifth speed (5th) is already selected, no processing is performed even if the UP switch is turned on.

If the UP switch is not on, the CPU next determines whether the DOWN switch is on (step S316). If the DOWN switch is on, the gear is reduced by one (step S318). The reduction of the shift speed means that the shift speed is switched one step toward the first speed (1st). However, in this embodiment, since the first speed (1st) is the lowest gear, this processing is performed in the range up to the first speed (1st). Even if the DOWN switch is turned on in a state where the first speed (1st) is already selected, no processing is performed.

When the DOWN switch is off, that is,
When neither the UP switch nor the DOWN switch is operated, the gear position is not switched. If the M position has been selected, the gear position is switched by the above processing, and the gear position switching processing routine ends.

On the other hand, if it is determined in step S304 that the M position has not been selected, that is, if the B position, D position, and L to 4 positions have been selected, the CPU turns off the M position indicator. (Step S320). Then, as described below, the CPU selects the gear position based on various parameters instead of the driver's instruction.

The CPU refers to the map shown in FIG. 10 based on the vehicle speed and determines whether or not there are two shift speeds capable of realizing the set deceleration (step S322). FIG.
As shown in the map of 0, in this embodiment, the range of the deceleration that can be realized at each shift speed overlaps. Therefore, there are a case where only one shift speed can realize the set deceleration and a case where there are two speed stages. If it is determined that there is only one achievable gear, the CPU executes a process for switching to the gear set based on the map (step S324).

If it is determined that there are two shift speeds for achieving the set deceleration, the remaining capacity SO of the battery 50 is determined.
With reference to C, it is determined whether or not the SOC is equal to or more than a predetermined value HL (step S326). As described above with reference to FIG. 13, when two shift speeds correspond to the set deceleration, at one speed, the set deceleration is realized by the regenerative operation of the motor 20, and the other is set. At the shift speed, the deceleration set by the power running operation of the motor 20 is realized. Therefore, when two gears correspond to the set deceleration, an appropriate gear can be selected according to the remaining capacity SOC of the battery 50.

When the remaining capacity SOC is equal to or higher than the predetermined value HL, it is desirable to consume power to avoid overcharging the battery 50. Accordingly, the CPU performs a power running operation of the motor 20 to achieve the set deceleration,
That is, the gear position having the larger gear ratio is selected from the two gear positions (step S328). The remaining capacity SOC is a predetermined value H
When it is smaller than L, it is desirable to charge the battery 50. Therefore, the CPU selects the speed stage on the side that achieves the set deceleration by regenerative operation of the motor 20, that is, the speed stage on the side with the smaller speed ratio among the two speed stages (step S330). Of course, it is preferable to provide a predetermined hysteresis for the determination in step S326 in order to prevent the selection of the two shift speeds from frequently switching according to the remaining capacity SOC.

When the gear to be used has been set by the above processing, the CPU ends the gear shift processing routine and returns to the deceleration control processing routine. Note that, in the above-described processing, switching of the shift speed is performed by a transmission control signal (FIG. 8).
3), and controls the on / off of the clutch and brake of the transmission 100 in accordance with the gear position set as shown in FIG.

When the change of the gear position is completed,
The CPU calculates a target value of the torque to be output by the motor 20 (step S400). FIG. 17 is a flowchart of a motor torque setting processing routine. When this processing is started, the CPU determines the various amounts necessary for calculating the torque of the motor 20 as the shift position (sp),
A target deceleration (dc *) and a deceleration (dc) are input (step S402). The deceleration (dc) is a value detected by the acceleration sensor 170 (see FIG. 1) mounted on the vehicle. Here, the absolute value of the value detected by the acceleration sensor 170 is used as the deceleration. Target deceleration (d
c *) is a value set in the deceleration setting processing routine (FIG. 15). In the deceleration setting processing routine, the correspondence between the vehicle speed and the deceleration is set as shown in the map of FIG. In the motor torque setting processing routine, a deceleration corresponding to the current vehicle speed is input. The deceleration corresponding to the current vehicle speed is determined based on the relationship set in the target deceleration setting processing routine.

When the B position is not selected, that is, when the M position, the D position, and the L to 4 positions are selected, the CPU sets a predetermined torque Tm0 set in advance as the target torque Tm of the motor 20. (Step S420). The predetermined torque Tm0 is set in advance by the following method according to the shift position and the selected gear position.

That is, according to the shift speed, the equations (2) to (2)
Using the gear ratios k1 to k5 shown in (6), the total torque to be output from the power sources of the engine 10 and the motor 20 is calculated based on the set deceleration, that is, the torque output to the axle 17. be able to. The braking force output from the engine 10, that is, the engine brake, is almost uniquely determined according to the rotation speed of the crankshaft 12.
Therefore, the torque to be output by the motor 20 can be obtained by subtracting the torque from the engine brake from the total torque output from the power source. In the present embodiment, a table for providing the calculated torque in relation to the shift position and the gear position is prepared, and the process of step S420 is executed by referring to the table.

When it is determined that the B position has been selected, the CPU sets the torque Tm of the motor 20 by so-called PID control (step S410). That is, the torque Tm is set by calculating the following equation using the deviation Δdc between the target deceleration dc * and the deceleration dc. Tm = k1 · Δdc + k2 · Σ (Δdc) + k3 · d
(Δdc) / dt; Δdc = dc * −dc; where d (Δdc) / dt means the time derivative of Δdc.

As described above, the torque Tm is obtained by multiplying the proportional term (the first term on the right side), the integral term (the second term on the right side), and the differential term (the third term on the right side) of the deviation Δdc by the gains k1, k2, and k3, respectively. Desired. The gain can be preset to an appropriate value so that the deviation Δdc converges to a value of 0 with desired responsiveness and stability. However, if the selected gear changes, the effect of the torque of the motor 20 on the deceleration changes. Therefore, in this embodiment, a gain is set for each gear. Since PID control is a well-known technique, further detailed description will be omitted. When the B position is selected, not only PID control but also various techniques for performing feedback control of the torque of the motor 20 can be applied.

When the target torque of the motor 20 is set by the above processing, the CPU returns to the deceleration control processing routine (FIG. 14), and the braking control processing (step S500).
The control of the operation of the motor 20 is executed. Motor 2
0 is operated by so-called PWM control. The CPU sets a voltage value to be applied to the coil of the stator 24.
Such a voltage value is given according to the rotation speed of the motor 20 and the target torque based on a table set in advance. When the motor 20 performs the regenerative operation, the voltage value is set as a negative value, and when the motor 20 performs the power running operation, the voltage value is set as a positive value. The CPU turns on / off each transistor of the drive circuit 40 so that the voltage is applied to the coil.
Control off. Since PWM control is a well-known technology,
Further detailed description is omitted.

By repeatedly executing the deceleration control processing routine described above, the hybrid vehicle of this embodiment can perform braking by the power source brake.
Of course, it goes without saying that braking by the wheel brake can be performed in conjunction with such braking.

In the hybrid vehicle of the present embodiment, an example of switching gears when the deceleration setting is changed will be described. FIG. 18 is an explanatory diagram showing the relationship between the setting of the deceleration and the switching of the shift speed.

It is assumed that the driver operates the slide knob 161 to reduce the deceleration during the intervals a1 to a3 in the drawing. It is assumed that the slide knob 161 is slid from the front to the rear as illustrated. In response to such an operation,
The target deceleration of the vehicle continuously decreases as shown in FIG.

Assume that the initial deceleration is realized only by the engine brake at the second speed (2nd). When the target deceleration is relaxed in the section a1, the shift speed is switched to the third speed (3rd), which is one stage higher, and braking is performed by regenerating the motor 20. Second speed (2n
In order to reduce the deceleration in the state of d), it is necessary to perform the power running operation of the motor 20, which is disadvantageous from the viewpoint of energy efficiency. Therefore, the switching to the third speed (3rd) is performed. In the section a1, deceleration according to the operation of the slide knob 161 is realized by reducing the amount of regeneration of the motor 20.

In the section a2 after the regenerative amount of the motor 20 reaches the value 0 at the third speed (3rd), in order to make the energy efficiency advantageous, the fourth speed (4th) is further increased by one speed.
, And braking is performed by regenerating the motor 20. In the section a2, the deceleration according to the operation of the slide knob 161 is realized by reducing the regeneration amount of the motor 20.

Similarly, in the section a3 after the regenerative amount of the motor 20 reaches the value 0 in the fourth speed (4th), in order to make the energy efficiency advantageous, the fifth shift speed is further increased by one stage. 5
th) and braking is performed by regenerating the motor 20. For example, in the section a3, when the state of charge of the battery 50 exceeds a predetermined reference value HL, braking is performed on the side that powers the motor 20. As a result, as shown by the one-dot chain line in the figure, the power stage torque of the motor 20 is gradually increased while maintaining the fourth speed (4th), whereby the deceleration according to the scanning of the slide knob 161 is realized. Here, the case where the remaining capacity SOC of the battery 50 exceeds the reference value HL at the boundary between the sections a2 and a3 has been described, but the transition to the power running can occur at any timing. For example, in the section a3, after the braking by the regenerative operation of the motor is started at the fifth speed (5th), the time tc
If the remaining capacity SOC exceeds the reference value HL at the time, switching to the gear position and motor torque indicated by the one-dot chain line is performed at that time as shown by the arrow in the figure.

According to the hybrid vehicle of the present embodiment described above, the desired deceleration can be realized with high accuracy by performing the so-called feedback control of the motor 20. Therefore, the driver can use the power source brake without discomfort. As a result, the hybrid vehicle of the present embodiment can improve the usefulness of the power source brake and greatly improve the operability of the hybrid vehicle.

In the hybrid vehicle according to the present embodiment, the deceleration can be changed in a wide range by integrally controlling the speed of the transmission and the torque of the motor 20. Therefore, the deceleration according to the driver's request can be realized in a wide range, and the usefulness of the power source brake can be greatly improved.

In the hybrid vehicle, the gear ratio of the transmission is set to a predetermined value in accordance with the target acceleration, and then the operation of the electric motor is feedback-controlled. Generally, control of the transmission gear ratio has relatively low responsiveness. Responsiveness required when performing open-loop control of the gear ratio to a predetermined value based on the target acceleration is also relatively low. Therefore, if the transmission is controlled by the open loop control, the hybrid vehicle can be controlled stably. Such control also has an advantage that the control of the transmission is simplified.

In the hybrid vehicle of this embodiment,
The braking at the deceleration set by the driver is performed only at the B position. By doing so, the driver can clearly recognize that braking at the deceleration set by him / her is realized, so that it is possible to perform driving without feeling uncomfortable. Further, an erroneous operation such as inadvertently changing the setting of the target deceleration can be avoided.

In this embodiment, the change of the gear position is performed as shown in FIG.
Went according to the map. On the other hand, it is also possible to perform feedback control on the gear change process. Such control will be described.

FIG. 19 is a flowchart of a deceleration control processing routine as a modification. When this process is started, the CPU performs a deceleration setting process (step S10).
0). This processing is the same as the processing (FIG. 15) described in the embodiment. Next, the CPU determines whether or not the accelerator is off (step S200), and performs processing for executing the power source brake only when the accelerator is off.

In the case where the accelerator is off, unlike the embodiment, prior to the gear change process, the CPU
Executes a motor torque setting process (step S40).
0). The motor torque setting process itself is the same as that of the embodiment (FIG. 17).

After the completion of the motor torque setting process, the CPU executes a speed changeover process. FIG. 20 is a flowchart of a shift speed switching process according to the modification. When this process is started, the CPU inputs a switch signal and a vehicle speed (step S432). Further, it is determined whether or not the M position is selected (step S434).
If the position has been selected, a process for switching to the gear position according to the driver's instruction is performed (step S44).
0 to S448). These processes are the same as the processes of steps S310 to S318 in the embodiment (FIG. 14).

In the gear shift processing routine of the modified example, the processing content when the M position is not selected is different from that of the embodiment. If the M position has not been selected, the CPU turns off the display of the M position indicator as in the embodiment (FIG. 14) (step S45).
0). Next, the CPU determines whether the torque Tm of the motor 20 has exceeded a predetermined maximum value Tmax (step S452). When the torque Tm exceeds the predetermined maximum value Tmax, the braking force by the engine brake is too large, and the power running torque of the motor 20 required to realize the desired deceleration is extremely large. Means that. Therefore, in such a case, the CPU increases the shift speed by one speed in order to reduce the effect of the engine brake (step S454). That is, the gear is switched to a lower gear ratio to reduce the braking force by the engine brake.

On the other hand, when the torque Tm of the motor 20 reaches the maximum value T
If it is determined that the value does not exceed max, the CPU determines whether the torque Tm is smaller than the minimum value Tmin (step S456). The torque Tm is equal to a predetermined minimum value Tm
The case where it is smaller than "in" means that the regenerative torque of the motor 20 required to realize the desired deceleration is extremely large because the braking force by the engine brake is too small. Therefore, in such a case, in order to increase the influence of the engine brake, the CPU sets the shift speed to 1st.
The number of steps is reduced (step S458). In other words, the gear position is switched to the side where the gear ratio is large, and the braking force by the engine brake is increased.

When the torque Tm of the motor 20 is at the minimum value Tmin
As described above, if the value falls within the maximum value Tmax or less, the CP
U ends the speed setting process routine without switching the speed, and returns to the deceleration control process routine (FIG. 19).
In the deceleration control processing routine, it is determined whether the torque of the motor Tm is within the rating, that is, not less than the minimum value Tmin and not more than the maximum value Tm.
ax is determined (step S
460). When the gear change is performed in the gear change processing routine (steps S454 and S454).
458) does not satisfy the condition of step S460. In such a case, the torque Tm is set again based on the shift speed after the switching has been performed (step S40).
0), the speed change process is executed again (Step S)
430).

In this manner, the motor torque setting process and the gear position switching process are repeatedly executed, and when the torque Tm of the motor 20 falls within the rated range, the CPU controls the operation of the motor 20 so that the torque Tm is output. Execute (step S500).

In the shift positions other than the B position, since the torque Tm of the motor 20 is preset to a value within the rating as described above, step S4
Condition 60 is always satisfied. Therefore, at shift positions other than the B position, the control processing of the modified example is substantially the same as that of the embodiment (FIG. 14).

The control processing of the above modification has the advantage that it is not necessary to prepare a map for setting the gear position. There is also an advantage that the motor can be operated in an appropriate state even when the characteristics of the motor and the engine change over time. In the above-described modification, an example is shown in which the rating of the motor 20 is used as the maximum value Tmax and the minimum value Tmin. These can be set to any value. For example, if the maximum value Tmax is set to 0, the motor 2
It is also possible to perform control for selecting a shift speed such that 0 performs regenerative operation. Therefore, for example, by changing the maximum value Tmax and the minimum value Tmin in accordance with the remaining capacity of the battery and then executing the control process of the modified example, a gear position suitable for maintaining the remaining capacity of the battery in a desired state is obtained. , Torque Tm can be set.

In this embodiment, the case where the braking is performed at the deceleration set by the driver has been described as an example. On the other hand, the present invention can be applied to a mode in which acceleration is performed at a positive acceleration set by the driver. It is sufficient that the driver can set the acceleration with the slide knob 161 shown in the present embodiment.
Step S2 of the deceleration control processing routine (FIG. 14)
In 50, the engine may be operated in a preset operation state according to the set acceleration instead of the process of idling the engine. Such processing can be substantially realized by replacing the deceleration in this embodiment with a positive acceleration.

Further, the present invention can be applied in a form in which the control unit 70 sets the target deceleration and acceleration by calculation, instead of setting the target deceleration and acceleration by the driver. As an example of such a case, there is a process of traveling while maintaining a constant inter-vehicle distance with a vehicle ahead. FIG. 21 is a flowchart of a fixed inter-vehicle traveling control processing routine. This process is similar to the deceleration control process routine, except that the CP
U is a process repeatedly executed. Further, this is a process that functions effectively when the driver selects a driving mode in which the vehicle travels while maintaining a constant inter-vehicle distance with the vehicle in front. It is assumed that the vehicle that performs this process has a hardware configuration in which a sensor that detects the distance between the vehicle and the front is added to the vehicle of the present embodiment. Examples of such a sensor include a sensor to which a laser, a radio wave, an ultrasonic wave, or the like is applied.

When this processing is started, the CPU detects an inter-vehicle distance to a vehicle ahead based on the output signal from the above-mentioned sensor (step S600). Next, a target acceleration is calculated based on the inter-vehicle distance and the target inter-vehicle distance (step S605). To calculate the target acceleration, for example, PI
D control can be applied. As described in the motor torque setting processing routine of this embodiment (FIG. 17),
The target acceleration is calculated by multiplying the proportional term, the integral term, and the derivative term of the deviation between the target inter-vehicle distance and the actual inter-vehicle distance by a predetermined gain. When the actual inter-vehicle distance is larger than the target inter-vehicle distance, the target acceleration has a positive value, and when the actual inter-vehicle distance is opposite, the target acceleration has a negative value.

On the basis of the target acceleration thus set, the CPU sets an operation point of the engine (step S610). The operating point can be set by various methods. For example, a table may be provided that provides a power change amount that specifies an increase or decrease in the power to be output from the engine according to the target acceleration, and the operating state of the engine may be changed based on the table. Also, a table that directly gives the engine speed and torque according to the vehicle speed and the target acceleration may be prepared.

When the operating state of the engine is set in this way, the CPU executes a speed change process (step S615). The content of this process may be substantially the same as the process (steps S320 to S330) in the shift position other than the M position in the process (FIG. 16) described in the embodiment. In FIG. 16, a map (FIG. 10) for giving a relationship between the deceleration and the shift speed is used. In the process of step S615, the process is performed using a map extended so as to be compatible with both positive and negative accelerations.

When the gear is set, the CPU performs a motor torque setting process (step S620). This processing is also substantially the same as the processing by feedback control (step S410) in the processing (FIG. 17) described in the embodiment. The gains k1, k2, and k3 may be set based on responsiveness and stability suitable for maintaining a headway. The CPU executes the operation of the engine and the motor at the operation points set by the above processing (step S625).

According to the hybrid vehicle that executes such control processing, it is possible to relatively easily realize driving while maintaining a constant inter-vehicle distance with the preceding vehicle. Therefore, stable traveling can be realized. In addition, if a situation in which only such a vehicle is running can be realized, the traffic state of the vehicle can be controlled, and traffic congestion can be reduced. Therefore, it can contribute to the social benefit of realizing smooth traffic. In the control process of the modified example (FIG. 21), if the distance between the vehicles is replaced by the vehicle speed, the control of traveling at a constant vehicle speed can be realized relatively easily.

In this embodiment, the engine 10 and the motor 20
Are directly connected to each other and connected to the axle 17 via the transmission 100. The present invention is applicable to a parallel hybrid vehicle having various other configurations, that is, a hybrid vehicle capable of directly transmitting output from an engine to an axle.

FIG. 22 is an explanatory diagram showing a configuration of a parallel hybrid vehicle as a modification. In the hybrid vehicle of the modified example, the engine E
G, and motors MG and AM. The three are
It is mechanically connected via a planetary gear PG.
That is, the engine EG is coupled to the planetary carrier PC, the motor MG is coupled to the sun gear SG, and the motor A
M is connected to the ring gear RG. Ring gear RG
Is connected to the axle DS. Motors MG and AM are connected to battery BT via drive circuits IV1 and IV2, respectively. The operating state of the hybrid vehicle of the present embodiment is controlled by the control unit ECU as in the case of the embodiment.

In the hybrid vehicle of the modified example, the power output from engine EG is distributed to two by planetary gear PG. One of the distributed powers is regenerated as electric power by the motor MG. The other is transmitted to the ring gear RG and the axle DS as mechanical power. By controlling the rotation speed of the motor MG, the rotation speed of the ring gear can be made to match the rotation speed required for the axle DS. Also, if power is supplied to run the motor AM,
The torque output to the axle DS can be made to match the required torque. The power regenerated by the motor MG is used as a part of the power.

The hybrid vehicle of the modified example has a motor AM
It is also possible to perform braking by the power source brake by regenerating the motor MG. By controlling the regeneration amounts of the motor AM and the motor MG, the deceleration of the vehicle can be controlled. If the present invention is applied to the hybrid vehicle of the modified example, and at least one of the regeneration amounts of the motor AM and the motor MG is feedback-controlled, braking at a desired deceleration requested by the driver can be realized. Of course, if the torque of the motor AM and the motor MG is controlled, the acceleration of the vehicle can also be controlled. Therefore, the present invention can be applied in a mode of controlling the positive acceleration.

As described above, the present invention is applicable to hybrid vehicles having various configurations. It is not always necessary to provide a transmission as in the embodiment. Further, in the embodiment, the example of the vehicle equipped with the transmission for changing the gear ratio stepwise has been described. On the other hand, the present invention can be applied to a vehicle equipped with a transmission capable of continuously changing the gear ratio.

The embodiments of the present invention have been described above. However, the present invention is not limited to these embodiments, and may be implemented in various other forms without departing from the gist of the present invention. Obviously you can get it.
The various control processes described in the present embodiment may be realized by hardware.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a hybrid vehicle as an embodiment.

FIG. 2 is an explanatory diagram showing an internal structure of the transmission 100.

FIG. 3 is an explanatory diagram showing a relationship between engagement states of clutches, brakes, and one-way clutches and shift speeds.

FIG. 4 is an explanatory diagram showing an operation unit 160 of a shift position in the hybrid vehicle of the embodiment.

FIG. 5 is an explanatory diagram showing a shift range operation unit provided on a steering.

FIG. 6 is an explanatory view showing an instrument panel of the hybrid vehicle in the embodiment.

FIG. 7 is an explanatory diagram showing connection of input / output signals to a control unit;

FIG. 8 is an explanatory diagram showing a relationship between a traveling state of a vehicle and a power source.

FIG. 9 is an explanatory diagram illustrating a relationship between a gear position of the transmission 100 and a traveling state of the vehicle.

FIG. 10 is an explanatory diagram showing a map of a combination of a vehicle speed, a deceleration, and a shift speed in the hybrid vehicle of the embodiment.

FIG. 11 is an explanatory diagram showing a relationship between deceleration and a shift speed at a vehicle speed Vs.

FIG. 12 is an explanatory diagram showing deceleration when the gear position is fixed.

FIG. 13 is an explanatory diagram schematically showing a relationship between a braking torque when the motor 20 performs the regenerative operation and a braking torque when the motor 20 performs the power running operation.

FIG. 14 is a flowchart of a deceleration control processing routine.

FIG. 15 is a flowchart of a deceleration setting processing routine.

FIG. 16 is a flowchart of a gear shift processing routine;

FIG. 17 is a flowchart of a motor torque setting processing routine.

FIG. 18 is an explanatory diagram showing a relationship between the setting of deceleration, a shift speed, and a motor torque.

FIG. 19 is a flowchart of a deceleration control processing routine as a modified example.

FIG. 20 is a flowchart of a shift stage switching processing routine as a modification.

FIG. 21 is a flowchart of a routine for a constant vehicle running control process.

FIG. 22 is an explanatory diagram showing a configuration of a hybrid vehicle as a modification.

[Explanation of symbols]

 10, 10A ... engine 12 ... crankshaft 13, 14, 15 ... output shaft 16 ... differential gear 17, 17A ... axle 20, 20A ... motor 22 ... rotor 24 ... stator 30, 30A ... torque converter 40, 40A, 41 ... drive Circuits 50, 50A Battery 70, 70A Control unit 100, 100A Transmission 110 Sub-transmission unit 112 First planetary gear 114 Sun gear 115 Planetary pinion gear 116 Planetary carrier 118 Ring gear 119 Output shaft 120 Main Transmission section 122 ... Rotary shaft 130 ... Planetary gear 130 ... Second planetary gear 132 ... Sun gear 134 ... Planetary carrier 136 ... Ring gear 140 ... Third planetary gear 142 ... Sun gear 144 ... Planetary carry 146 ring gear 150 fourth planetary gear 152 sun gear 154 planetary carrier 156 ring gear 160, 160A operating section 161 slide knob 162 shift lever 163 snow mode switch 164 steering 166L, 166R, 168L, 168R switch 170: acceleration sensor 202: fuel gauge 204: speedometer 206: engine tachometer 208: engine water temperature gauge 210L, 210R: direction indicator indicator 220: shift position indicator 224: deceleration indicator

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) F02D 29/00 F02D 29/02 341 29/02 F16H 61/02 341 B60K 9/00 Z F16H 61/02 // F16H 59 : 48 (72) Inventor Makoto Nakamura 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Co., Ltd. (72) Inventor Masaya Amano 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation F-term (reference) 3D041 AA31 AA33 AA66 AA80 AB01 AC01 AC08 AC15 AC18 AD00 AD02 AD03 AD10 AD13 AD15 AD17 AD22 AD23 AD31 AD35 AD39 AD42 AD51 AE02 AE03 AE11 AE14 AE30 AE32 AE41 AF00 AF01 3D044 AA04 AA45 AB01 AC05 AD17 AC21 AD17 AC22 AE22 3G093 AA05 AA07 AA16 AB00 AB02 BA23 BA24 CB07 DA06 DB00 DB05 DB11 DB16 DB21 EB00 EB03 FA04 FA10 FA13 FB06 3J052 AA04 AA20 CB12 EA04 EA05 GA01 GA21 GC46 GC51 HA02 KA01 LA08 5H115 PG29 PU24 PU23 PI24 PI23 QI09 QI12 QN03 QN04 QN23 QN24 RB08 RB22 RE03 SE04 SE05 SE08 SF18 SJ12 SJ13 TB01 TE02 TE07 TE08 TI02 TO02 TO05 TO23 TU16 TW07 TZ07

Claims (7)

[Claims] 1. A hybrid vehicle having an axle coupled to a power source including an engine and an electric motor and capable of running and braking by torque of the power source, input means for inputting a target acceleration of the vehicle. An engine control unit that operates the engine in an operation state determined based on the target acceleration; a detection unit that detects the acceleration of the vehicle; and controls the operation of the electric motor based on a deviation between the acceleration and the target acceleration. And a motor control means for causing the deviation to converge within a predetermined range. 2. The hybrid vehicle according to claim 1, wherein a transmission capable of changing a plurality of gear ratios between a rotation speed of the power source and a rotation speed of the axle is disposed between the power source and the axle. Transmission control means for controlling the transmission to switch the speed ratio based on a difference between the acceleration and the target acceleration, wherein the motor control means includes the deviation and the speed ratio A hybrid vehicle that is a means for controlling the operation of the electric motor based on 3. The hybrid vehicle according to claim 1, wherein a transmission capable of changing a plurality of gear ratios between a rotation speed of the power source and a rotation speed of the axle is disposed between the power source and the axle. And storage means for storing a predetermined relationship between the target acceleration and the gear ratio; and controlling the transmission to a gear ratio determined based on the target acceleration in accordance with the relationship. And a transmission control means for switching the electric motor, wherein the electric motor control means is means for controlling operation of the electric motor based on a deviation between the acceleration and the target acceleration and the gear ratio. 4. The hybrid vehicle according to claim 1, wherein said input means is means for inputting a target acceleration instructed by a driver of said hybrid vehicle. 5. The hybrid vehicle according to claim 1, wherein an execution instruction input unit inputs an instruction to execute control based on the target acceleration, and the input unit and the engine only when the instruction is input. A hybrid vehicle including a control unit, a detection unit, and a permission unit that permits all operations of a motor control unit. 6. The hybrid vehicle according to claim 1, wherein the target acceleration is acceleration at the time of braking by a torque of the power source, and wherein the engine control means is configured to apply a braking torque to an axle. A hybrid vehicle that is a means for driving an engine. 7. A method for controlling a hybrid vehicle having an axle coupled to a power source including at least an engine and an electric motor and capable of running and braking by torque of the power source, comprising: (a) a target for the vehicle; Inputting an acceleration; (b) operating the engine in an operating state determined based on the target acceleration; (c) detecting the acceleration of the vehicle; and (d) detecting the acceleration and the target acceleration. Controlling the operation of the electric motor based on a deviation from the above.