JP2010179845A - Drive control apparatus and drive control method of hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform drive control in a hybrid vehicle capable of preventing over rotation of a motor while suppressing increase of a size and a cost of a driving apparatus for a vehicle. <P>SOLUTION: The vehicle includes an engine 1 connected to a driving wheel 5 via a planetary gear mechanism 2, a first motor connected to the engine 1 and the driving wheel 5 via the planetary gear mechanism 2, and a second motor connected to the driving wheel 5. The vehicle further includes a power connection/disconnection mechanism for performing switching between a power transmission state and a non-power transmission state relating to a connection state of the engine 1, the first motor, and the second motor relating to the driving wheel 5. When variations in rotational speed of the driving wheel 5 is determined to be larger than a predetermined value, the connection of the engine 1, the first motor, and the second motor to the driving wheel 5 is switched to the non-power transmission state via the power connection/disconnection mechanism. When being switched to the non-power transmission state, the first motor and the second motor are made to perform rotational speed control. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a drive control technique in a split type hybrid vehicle in which drive wheels can be driven by an engine and an electric motor.

  The engine and the first electric motor (generator) are connected to the drive wheels via a planetary gear mechanism. Further, the second electric motor is connected to the drive wheel. And when the rotation speed change more than predetermined occurs in a drive wheel, the brake for electric motors will be operated and rotation of the 2nd electric motor (drive motor) will be stopped. This mechanically prevents the motor from over-rotating. Here, the over-rotation of the electric motor occurs when the rotational speed of the driving wheel is suddenly changed such as sudden braking or wheel locking.

JP 09-048334 A

In the above prior art, in order to prevent the motor from over-rotating, a motor brake device for braking the motor is required. For this reason, it will lead to the enlargement of a drive device and the cost increase only for the brake device for electric motors.
It is an object of the present invention to perform drive control in a hybrid vehicle capable of preventing over-rotation of an electric motor while suppressing an increase in size and cost of a vehicle drive device.

In order to solve the above problems, the present invention provides an engine connected to a drive wheel via a planetary gear mechanism, a first electric motor connected to the engine and the drive wheel via the planetary gear mechanism, and a connection to the drive wheel. A second electric motor. Further, a power interrupting mechanism that switches between a power transmission state and a non-power transmission state with respect to the connection state of the engine, the first motor, and the second motor to the drive wheels is provided.
And if it determines with the rotation speed change of the said driving wheel being larger than predetermined value, the connection state of the engine with respect to a driving wheel, a 1st electric motor, and a 2nd electric motor will be switched to a non-power transmission state via a power intermittent mechanism. In synchronism, the first motor and the second motor are set to rotation speed control.

  According to the present invention, when the rotational speed change of the drive wheel becomes larger than a predetermined value and the motor may be over-rotated, the state is switched to the non-power transmission state. This can prevent over-rotation of the electric motor. Furthermore, by making the electric motor have rotational speed control, the transition from the non-power transmission state to the power transmission state is made smooth.

It is a figure which shows the system configuration | structure which concerns on embodiment based on this invention. It is a figure which shows the structure of the over-rotation prevention process part which concerns on embodiment based on this invention. It is a figure which shows the process of the over-rotation prevention process part which concerns on embodiment based on this invention. It is a figure which shows the process of the over-rotation prevention control part which concerns on embodiment based on this invention. It is a figure which shows the process of the return control part which concerns on embodiment based on this invention. It is an alignment chart which shows the relationship between the rotation speed of a generator, an engine, and a motor. It is a collinear diagram which shows the reason for the generator over-rotating at the time of sudden braking. It is a collinear diagram which shows the state which prevented the generator from overrotating. It is a figure which shows the alignment chart of the system which has several power transmission paths. It is a figure which shows the example of a time chart at the time of tire lock. It is a figure which shows the example of a time chart at the time of a return process.

Next, embodiments of the present invention will be described with reference to the drawings.
(Constitution)
FIG. 1 is a schematic configuration diagram illustrating a drive control apparatus for a hybrid vehicle according to the present embodiment.
In the present embodiment, the power transmission path includes a first axis to a third axis L1 to L3.
On the first axis L1, the output shaft 1a of the engine 1 is connected to the generator 3 via the planetary gear mechanism 2. The output shaft 1 a of the engine 1 is connected to the final output shaft 4 via the planetary gear mechanism 2. The final output shaft 4 is connected to the left and right drive wheels 5 via a differential gear.

The planetary gear mechanism 2 includes a sun gear S, a pinion P that meshes with the sun gear S, a ring gear R that meshes with the pinion P, and a carrier CR that rotatably supports the pinion P. The carrier CR is connected to the output shaft 1 a of the engine 1. The sun gear S is connected to the generator 3 via the transmission shaft 6. The ring gear R is connected to the final output shaft 4 by a unit output shaft 7 via a transmission mechanism 8 described later.
The generator 3 includes a rotor disposed rotatably, a stator disposed around the rotor, and a coil wound around the stator. Then, the generator 3 generates electric power by the rotation transmitted through the transmission shaft 6. The coil is connected to the battery 12 via the inverter 14 and supplies power to the battery 12 for charging.

  Further, a drive motor 9 for driving the drive wheels 5 is provided on the second axis L2. An output shaft 9 a of the drive motor 9 is connected to the plurality of counter drive gears 10 and 11. The drive motor 9 includes a rotor fixed to the motor output shaft 9a, a stator disposed around the rotor, and a coil wound around the stator. The coil is connected to the battery 12 via the inverter 13, and current is supplied from the battery 12. Here, the drive motor 9 generates regenerative power by receiving rotation from the drive wheels 5 when the vehicle is decelerating, and supplies the regenerative power to the battery 12.

The final output shaft 4 is disposed on the third axis L3. A speed change mechanism 8 is connected to the final output shaft 4. The output shaft of the drive motor 9 is connected to the transmission mechanism 8.
The transmission mechanism 8 has a plurality of shift stages and switches to a shift stage according to a command from the clutch control unit 23. In FIG. 1, the case of a gear train for two speed stages is illustrated as the speed change mechanism 8, and there are two clutches CL1 and CL2 as power interrupting mechanisms for interrupting connection with the final output shaft 4 for each gear train. . With this speed change mechanism 8, the engine 1, the generator 3, and the drive motor 9 can be connected to the drive wheels 5 through a plurality of transmission paths.

  With the above configuration, the driving force of the engine 1 can be transmitted to the final output shaft 4 and can be transmitted to the final output shaft 4. As a result, the drive mode includes an engine drive mode for driving only the engine 1, a motor drive mode for driving only the drive motor 9, and an engine / motor drive mode for driving the engine 1 and the drive motor 9. Further, by controlling the electric power generated in the generator 3, the rotational speed of the transmission shaft 6 can be controlled. Furthermore, the engine 1 can be started by the generator 3.

Next, the control system of the hybrid vehicle will be described.
The control system of the present embodiment includes an integrated controller unit 20, which is a higher-level control system, an engine control unit 21, a motor / generator control unit 22, and a clutch control unit 23.
The control system includes an accelerator sensor 30, a wheel speed sensor 31, a brake sensor 32, and a battery sensor 33.
The accelerator sensor 30 detects an accelerator opening α of the accelerator pedal. The wheel speed sensor 31 detects the rotational speed of the wheel. The brake sensor 32 detects the brake depression amount β of the brake pedal. The battery sensor 33 detects the charge amount SOC of the battery 12. These sensors 30 to 33 supply the detected detection values to the integrated controller unit 20. The integrated controller unit 20 calculates the vehicle speed V based on the rotation speed signal from the wheel speed sensor 31.

The integrated controller unit 20 controls the entire hybrid vehicle while managing the energy consumption of the entire vehicle. The integrated controller unit 20 calculates a target driving force based on the accelerator opening α and the vehicle speed V from the accelerator sensor 30. Further, the integrated controller unit 20 calculates a target braking force based on the brake depression amount β from the brake sensor 32. The integrated controller unit 20 calculates control command values for the engine 1, the generator 3, and the drive motor 9 based on the vehicle speed, the target driving force, and the target braking force, and the engine control unit 21, the motor / generator, respectively. This is supplied to the control unit 22 and the clutch control unit 23. Further, for example, when the brake is depressed and the brake depression amount β is input from the brake sensor 32, an engine 1 OFF signal for making the engine 1 in a non-driving state is supplied to the engine control unit 21, and when the brake is released, the engine 1 is turned off. The engine 1 ON signal to be driven is supplied to the engine control unit 21.
Further, as shown in FIG. 2, the integrated controller unit 20 includes an over-rotation prevention processing unit 20A. The over-rotation prevention processing unit 20A includes an over-rotation prevention control unit 20Aa and a return control unit 20Ab.

Next, the process of the over-rotation prevention control unit 20Aa will be described with reference to FIG. The process of the over-rotation prevention control unit 20Aa is performed at a predetermined sampling period. The over-rotation prevention control unit 20Aa stops the process when the return control unit 20Ab performs the process of connecting the clutch (step S260).
First, in step S10, it is determined whether or not the generator 3 or the drive motor 9 is likely to over-rotate. In this embodiment, when the rotation speed change of the drive wheel 5 is more than a predetermined value, it is determined that the generator 3 or the drive motor 9 is likely to over-rotate. However, when the two clutches CL1 and CL2 as the power interrupting mechanism are opened, the generator 3 or the drive motor 9 is over-rotated even if the rotational speed change of the drive wheels 5 is more than a predetermined value. It is determined that this is not the case. If it is determined that the generator 3 or the drive motor 9 is likely to over-rotate, the process proceeds to step S20. On the other hand, if it is determined that the generator 3 or the drive motor 9 is not in a situation where the generator 3 or the drive motor 9 is likely to be over-rotated, the process is terminated and the process returns.

In step S20, a release command for releasing all the clutches CL1 and CL2 is output to the clutch control unit 23. In addition, the motor / generator control unit 22 outputs a command for performing the rotational speed control using the rotational speed immediately before the clutch of the generator 3 or the drive motor 9 as the target rotational speed. Output.
Next, in step S30, an activation command is output to the overspeed prevention control unit 20Aa. Subsequently, in step S40, an activation command is output to the return control unit 20Ab. Then return.

Next, the process of the over-rotation prevention control unit 20Aa will be described with reference to FIG. The over-rotation prevention control unit 20Aa ends the process when an end signal is input.
When the over-rotation prevention control unit 20Aa is activated, the over-rotation prevention control unit 20Aa determines whether or not the battery input / output is limited based on the charging rate of the battery 12 or the like in step S100. For example, when the temperature of the battery 12 is in a low temperature state such as 0 ° C. or lower, or when the charging rate of the battery 12 is equal to or higher than a predetermined charging rate, it is determined that the battery input / output is limited. The predetermined charging rate may be changed depending on the temperature of the battery 12 or the like. If the battery input / output is restricted, the process proceeds to step S110. If there is no limit on battery input / output, the process proceeds to step S120.

In step S110, the amount of power generated by the generator 3 is estimated based on the signal from the motor / generator control unit 22. Further, based on the signal from the motor / generator control unit 22, the power consumption in the drive motor 9 is estimated. Note that when the drive motor 9 is in the rotational braking state, the power consumption is a negative value. A negative value of power consumption is the amount of power generation.
Then, it is determined whether or not the power obtained by subtracting the power consumption from the power generation amount is less than the allowable power that can be input and output by the battery 12. If the power is less than the allowable power, the process ends and returns.

On the other hand, when the power obtained by subtracting the power consumption from the power generation amount is equal to or higher than the allowable power that can be input / output by the battery 12, the power balance that the power obtained by subtracting the power consumption from the power generation amount becomes the allowable power that can be input / output by the battery 12 Perform suppression control.
In the power balance suppression control, for example, the power consumption of the generator 3 and the drive motor 9 is controlled so that the power obtained by subtracting the power consumption from the power generation amount is less than the allowable power that can be input and output by the battery 12. For example, a signal for reducing the number of rotations of the generator 3 to suppress the amount of power generation is output to the motor / generator control unit 22, or the number of rotations of the drive motor 9 is increased to the motor / generator control unit 22 for consumption. The number of revolutions at which the amount of power generation and the power consumption are equal is calculated by outputting a signal for increasing the power, and the number of revolutions of the generator 3 and the drive motor 9 is controlled. Thereafter, the process is terminated and the process returns.

  In step S120, the actual vehicle speed is estimated, and whether or not the difference between the converted rotational speed of the drive wheel 5 corresponding to the estimated actual vehicle speed and the current rotational speed of the drive wheel 5 is equal to or less than a predetermined rotational speed difference. judge. The actual vehicle speed is estimated from the wheel speed of the driven wheel, for example. If it is determined that the rotational speed difference is equal to or smaller than the predetermined rotational speed difference, the process proceeds to step S130. If it is determined that the rotational speed difference is greater than the predetermined rotational speed, the process proceeds to step S140. Here, in step S120, the difference between the actual vehicle speed and the rotational speed of the wheel is observed, but the present invention is not limited to this. The vehicle speed immediately before or after the clutch is disengaged is acquired, and if the difference between the acquired vehicle speed and the current vehicle speed is less than or equal to the predetermined range, the process proceeds to step S130. Also good.

In step S <b> 130, a signal for controlling the rotational speed of the generator 3 and the drive motor 9 with the current rotational speed as the target rotational speed is output to the motor / generator controller 22. Note that the number of revolutions is initially the number of revolutions immediately after the clutch is disengaged. Then return.
On the other hand, in step S140, a signal for performing the rotational speed control by making the target rotational speed smaller than the current target rotational speed by a predetermined number of times is output to the motor / generator control unit 22 and the motor / generator control unit 22. Then return.

Next, the processing of the return control unit 20Ab will be described with reference to FIG.
First, in step S200, it is determined whether or not there is a driving force request from the driver based on the signal from the accelerator sensor. If it is determined that there is a driving force request, the process proceeds to step S270. When it is determined that there is no driving force request, the process proceeds to step S210.
In step S210, it is determined whether or not the actual vehicle speed can be determined. That is, it is determined whether or not the estimated vehicle speed deviates from the actual vehicle speed. The estimated vehicle speed is estimated from the rotational speed of the driven wheel. If the actual vehicle speed can be determined, the process proceeds to step S220. If it is determined that the actual vehicle speed cannot be determined, the process proceeds to step S230.

Whether or not the estimated vehicle speed deviates from the actual vehicle speed is determined by any one of the following (a) to (d), for example.
(A) Based on the detection value of the longitudinal G sensor, the speed change of the number of rotations of the driven wheel is compared with the longitudinal acceleration change. And when the variation | change_quantity of the rotation speed of a driven wheel with respect to the change of a longitudinal acceleration is outside a predetermined range, it determines with a deviation. When the longitudinal acceleration change is small, the vehicle speed change is small.
(B) Based on the detected value of the brake hydraulic pressure sensor, when the brake hydraulic pressure of the driven wheel is high, it is determined that there is a deviation. When the brake oil pressure of the driven wheel is high, a strong braking force is applied to the driven wheel, so that the correlation between the rotational speed of the driven wheel and the vehicle speed is lost.

(C) When the change in the estimated vehicle speed estimated from the number of rotations of the driven wheel is larger than a predetermined value, it is determined as a deviation. If the change in the estimated vehicle speed estimated from the rotational speed of the driven wheel is greater than a predetermined value, it can be determined that the driven wheel is slipping. The reason for this can be estimated that when the estimated vehicle speed change is larger than the longitudinal G change of the vehicle that occurs in the running state, the vehicle speed does not change, but acceleration slips and braking slips occur in the driven wheels. Because.
(D) If the amount of change in the rotational speed of the driven wheel is larger than a predetermined value, it is determined that the driven wheel is slipping and it is determined as a deviation.

In step S220, the rotational speed of the drive motor 9 and the rotational speed of the generator 3 corresponding to the actual vehicle speed are calculated, and the motor / generator control unit 22 issues a command for rotational control at the calculated motor rotational speed or the generator rotational speed. Output to. Thereafter, the process proceeds to step S230.
In step S230, a command for slightly increasing the clutch hydraulic pressure and setting the clutch in the standby state is output to the clutch control unit 23. Thereafter, the process proceeds to step S240. The standby state means that the interval between the clutches, which is between the input shaft and the output shaft, is reduced to shorten the switching time when the released clutch is switched to the engaged state.

In step S240, it is determined whether or not the fastening is possible. For example, when the rotation speed of the drive wheel 5 is equal to or less than a predetermined rotation speed and the change in the rotation speed is less than a predetermined value, it is determined that the engagement is possible. If it is not in the state which can be fastened, it will return to step S200. When it determines with the state which can be fastened, it transfers to step S250.
In step S250, a command to engage the clutch that is released in the standby state is output to the clutch control unit 23, and the process proceeds to step S260.
In step S260, the controller 21 and 22 are instructed to return to normal processing. In addition, an end signal is output to the over-rotation prevention control unit 20Aa. Then return.

On the other hand, when it is determined in step S200 that there is a driving force request and the process proceeds to step S270, it is determined whether or not the actual vehicle speed can be determined. If it is determined that the actual vehicle speed can be determined, the process proceeds to step S280. If it is determined that the actual vehicle speed cannot be determined, the process proceeds to step S290. The determination as to whether or not the actual vehicle speed can be determined is the same as in step S210 above, and the estimated vehicle speed deviation state is determined.
In step S280, the transmission mechanism 8 outputs to the clutch control unit 23 a command to enter an engaged state with a gear ratio corresponding to the actual vehicle speed. Thereafter, the process proceeds to step S260.
In step S290, a command to be engaged at the gear position having the smallest reduction ratio is output to the clutch control unit 23. Thereafter, the process proceeds to step S260.

  The engine control unit 21 controls the throttle opening θ of the engine 1 in accordance with the engine speed NE input from the engine speed sensor 48 based on the control command input from the integrated controller unit 20. As a result, the engine control unit 21 controls the output of the engine 1. However, during the overspeed prevention process by the overspeed prevention processing unit 20A, the engine control unit 21 sets the speed when the power transmission state with the drive wheels 5 is switched from the power transmission state to the non-power transmission state as the target speed. To control.

  The motor / generator control unit 22 includes a torque control unit and a rotation speed control unit. Then, the inverters 13 and 14, the drive motor 9, and the field current of the generator 3 are controlled so that the control command input from the integrated controller unit 20 is obtained. However, when an instruction for rotational speed control is input from the over-rotation prevention processing unit 20A, the drive motor 9 and the generator 3 are controlled by rotational speed control. Note that the initial value of the target rotational speed of the rotational speed control is the rotational speed when the power transmission state with the drive wheels 5 is switched to the non-power transmission state. In addition, a command for setting the engine speed for the target speed is also output to the engine control unit 21 as appropriate.

  In addition, the clutch control unit 23 controls the clutches CL1 and CL2 in the transmission mechanism 8 so that the gear stage according to the vehicle speed is normally set. However, when a clutch control command is input from the over-rotation prevention processing unit 20A, the clutches CL1 and CL2 are engaged based on the clutch control command from the over-rotation prevention processing unit 20A until an over-rotation prevention end signal is input. And control the opening. In addition, when a command to enter the standby state in the released state is input, the clutch pressure is increased to the preliminary clutch pressure, and the transition time to the engaged state can be shortened.

(Operation / Action)
Since the transmission mechanism 8 has a plurality of transmission paths, which have different reduction ratios, the maximum torque required for the engine 1 and the drive motor 9 is small. For this reason, the whole hybrid unit can be miniaturized.
The engine torque is distributed by the planetary gear mechanism 2 to the ring gear torque TR and the generator 3 torque. The ring gear torque is transmitted to the final output shaft 4.

  Here, the engine 1, the generator, and the drive motor are connected (coupled) by the planetary gear mechanism 2 as described above. With this connection relationship, as shown in FIG. 6 (1), the generator 3, the engine 1, and the drive motor 9 are arranged in order on the collinear chart, so that the dynamic operation of the planetary gear mechanism 2 can be simply expressed. It is possible to introduce a rigid lever model (a relationship in which three rotation speeds are always connected by a straight line). Here, the collinear diagram is a velocity diagram used in a method for obtaining a simpler and easier-to-understand drawing instead of a method for obtaining a gear ratio of a differential gear. The vertical axis represents the rotational speed (rotational speed) of each rotating element, the horizontal axis represents each rotating element, and the interval between the rotating elements is a collinear lever ratio based on the gear ratio λ of the sun gear S and the ring gear R. It is arranged so as to be (1: λ). In this way, the three rotational speeds are always connected in a straight line, and because the engine inertia is large, when the rotational speed on the motor side, that is, on the drive wheel side changes suddenly, The number of rotations of the generator changes according to the nomograph lever ratio. FIGS. 6 (2) to 6 (5) show examples of states in the respective travel modes.

  For example, when a wheel spin state, which is an abnormal rotation state of the drive wheel 5 due to sudden acceleration, or the like, that is, when a change in rotational speed exceeding a predetermined value occurs in the drive wheel 5, the carrier inertia torque is used as an engine torque to stop the wheel spin on the carrier. Occurs in the opposite direction. In this case, the combined torque of the carrier inertia torque and the engine torque becomes the carrier torque. On the other hand, by distributing the carrier torque to the ring gear torque and the generator 3 torque at a predetermined ratio determined by the planetary gear mechanism 2, the carrier torque, the ring gear torque, and the generator 3 torque are each normally run. The torque is in the opposite direction to the hour. If this state continues, the number of revolutions of the generator 3 increases, the number of revolutions NG of the generator 3 increases rapidly, and it may become difficult to control the generator 3. Further, when the drive wheel 5 is over-rotated, the drive motor 9 connected to the final output shaft 4 may be over-rotated.

  In addition, when the wheels that are abnormal in rotation of the drive wheels 5 are locked due to sudden deceleration, that is, when a change in the rotational speed of the drive wheels 5 exceeds a predetermined value, the wheels are locked in the same direction as the engine torque due to the sudden deceleration. The carrier inertia torque is generated in the carrier, and the combined torque of the carrier inertia torque and the engine torque becomes the carrier torque. The carrier inertia torque generated by the wheel lock is opposite to the case of wheel spin. The carrier torque is distributed to the ring gear torque and the generator 3 torque at a predetermined ratio determined by the planetary gear mechanism 2, and the carrier torque, the ring gear torque, and the generator 3 torque are respectively in normal driving. The torque is greater in the same direction and compared to normal driving.

On the other hand, since the wheel is locked, the rotation of the ring gear becomes zero, and together with the generation of the large torque described above, the number of revolutions of the generator 3 increases rapidly, which may make it difficult to control the generator 3. .
In addition, when a wheel locks as mentioned above, the rotation speed of the drive motor 9 also falls rapidly. In this case, since the engine 1 has a large inertia, as described above, the generator 3 side is over-rotated around the engine 1 as shown in the alignment chart shown in FIG.

  On the other hand, when it is determined that there is a possibility that the drive wheel 5 is in an abnormal rotation state and the generator 3 or the drive motor 9 is in an over-rotation state as described above, the engine 1 and the generator 3 are driven from the drive wheel 5. Then, the drive motor 9 is disconnected. As a result, as shown in FIG. 8, the generator 3 or the drive motor 9 is prevented from over-rotating. Furthermore, when the power transmission state is cut off, the generator 3 and the drive motor 9 are rotated by rotation speed control in synchronization with each other, so that the transition from the non-power transmission state to the transmission state is made smooth.

Further, when returning from the overspeed prevention control to the normal state, as shown in FIG. 9, when there are a plurality of power transmission paths by the speed change mechanism 8, it is set to a gear position according to the actual vehicle speed or the reduction ratio is the highest. Set to a smaller gear. Here, in FIG. 9, the power interrupting mechanisms 1 and 2 have different speed reduction ratios, and the difference in the number of rotations of each transmission path represents the speed reduction ratio.
FIG. 10 shows an example of a time chart at the time of over-rotation prevention processing when the tire is locked. The broken line portion is the process for preventing over-rotation.

In this example, the change in the number of revolutions of each element when preventing over-rotation of the electric motor by disconnecting the power transmission mechanism at the time of a sudden brake command is shown. By disconnecting the power transmission mechanism by the over-rotation prevention control, the rotational speeds of the motor and the generator 3 can be maintained at a constant rotational speed despite the sudden change in the rotational speed of the output shaft.
FIG. 11 shows an example of a time chart until the driving force is restored by the rotation speed control. That is, the time chart shows the shortening of the return time by the rotation speed maintenance control after separation by the power interrupting mechanism.

In FIG. 11, after the output shaft rotational speed is suddenly reduced and the power transmission mechanism is disconnected to prevent over-rotation, one keeps the rotational speed of the motor at the original rotational speed, and the other keeps the rotational speed of the motor. It is a time chart when it matches with the output shaft rotation speed. In the case of a sudden change in the output shaft speed that is expected to return to the original speed, the speed is adjusted to the output shaft speed when the speed is maintained at the speed immediately before separation or at a speed close to it. It shows that it can return earlier than the case.
Here, the generator 3 constitutes a first electric motor. The drive motor 9 constitutes a second electric motor. The clutches CL1 and CL2 of the speed change mechanism 8 constitute a power interrupt mechanism. Step S20 constitutes an overspeed preventing means. The over-rotation prevention control unit 20Aa constitutes a rotation speed control means. Steps S210 and S270 constitute vehicle speed estimation means and estimated vehicle speed validity determination means.

(Effect of this embodiment)
(1) An engine 1 connected to the drive wheel 5 via the planetary gear mechanism 2, a first electric motor connected to the engine 1 and the drive wheel 5 via the planetary gear mechanism 2, and a first motor connected to the drive wheel 5. And a power interrupting mechanism that switches between a power transmission state and a non-power transmission state with respect to a connection state of the engine 1, the first motor, and the second motor with respect to the drive wheel 5. When the over-rotation preventing means determines that the change in the rotational speed of the drive wheel 5 is greater than a predetermined value, the connection state of the engine 1, the first electric motor, and the second electric motor to the drive wheel 5 is not determined via the power interrupt mechanism. Switch to the power transmission state. If the rotational speed control means determines that the rotational speed change of the drive wheel 5 is greater than a predetermined value, the rotational speed control is performed on the first motor and the second motor.
When over-rotation of the first and second motors is predicted, the final output shaft 4 and the first and second motors can be disconnected. As a result, it is possible to prevent the influence of a sudden change in the rotational speed of the drive wheels 5 due to road surface changes, ABS operation, or the like from being transmitted to the first and second electric motors. Further, by controlling at least the rotational speeds of the first and second electric motors, it is possible to easily and reliably prevent the motor from over-rotating.

(2) The rotation speed control means sets the target rotation speed of the rotation speed control to the rotation speed when switched to the non-power transmission state by the over-rotation prevention means when the speed change of the vehicle speed is not more than a predetermined value.
By predicting that the output shaft rotation will return to the rotational speed corresponding to the actual vehicle speed, and setting the rotational speed before and after disconnecting the intermittent mechanism as the target rotational speed, it is possible to shorten the time for adjusting the rotational speed during the return control. As a result, it is possible to return to the normal traveling state in a short time and transmit the driving force.

(3) The rotational speed control means suppresses the target rotational speed of the rotational speed control when the rotational speed of the first electric motor or the second electric motor is determined to be an excessive rotational speed with respect to the vehicle speed.
The rotational speeds of the first and second electric motors can be controlled by the rotational speed away from the over-rotation region. As a result, the possibility of overspeeding again can be kept low.
(4) The rotation speed control means controls the rotation speeds of the first motor and the second motor so that the sum of the power generation amount and the power consumption of the first motor and the second motor becomes equal.
It is possible to prevent an excessive load on the battery 12 even in a situation where input / output to the battery 12 is restricted due to a cryogenic temperature, a malfunction of the battery 12, or a situation where it is desired to maintain the battery SOC.

(5) The driving force request detecting means detects the presence or absence of a driving force request by the driver. When the over-rotation prevention processing end means determines that there is a driving force request from the driver in a state where the over-rotation prevention means is switched to the non-power transmission state by the operation of the over-rotation prevention means, the transmission mechanism 8 is set to a gear position corresponding to the vehicle speed. At the same time, the connection state of the engine 1, the first motor, and the second motor with respect to the drive wheels 5 is switched to the power transmission state.
Since it becomes possible to meet the driving force request from the driver, drivability is improved. Further, even if the rotation of the drive wheel 5 suddenly changes to the actual vehicle speed even when returning from a tire lock or the like, it is possible to suppress over-rotation of the electric motor by selecting a reduction ratio that makes it difficult for the electric motor to over-rotate.

(6) If the over-rotation prevention process ending means determines that the estimated vehicle speed deviates from the actual vehicle speed, it sets the transmission mechanism 8 to the state with the smallest reduction ratio.
Even when the actual vehicle speed cannot be estimated, since it is connected to the power transmission mechanism having the smallest reduction ratio, it is possible to realize a state in which the driving force that can be generated is small, but is most unlikely to fall into excessive rotation.

(7) If the over-rotation preventing means determines that there is no request for driving force by the driver, the power interrupting mechanism that has switched to the non-power transmission state is used for the short-time non-power transmission to return to the power transmission state. Set to the standby state.
By setting the power interrupting mechanism in a standby state so that the power can be returned to the state where power can be transmitted as soon as possible, the driving force can be generated immediately after the start of the recovery process.
(Modification)
(1) The vehicle speed may be estimated from the rotational speed of the driven wheel and the vehicle front-rear G sensor. When the actual vehicle speed can be predicted by a G sensor front-rear G change or GPS information analysis, the vehicle speed may be estimated based on the prediction.

DESCRIPTION OF SYMBOLS 1 Engine 2 Planetary gear mechanism 3 Generator 4 Final output shaft 5 Drive wheel 6 Transmission shaft 7 Unit output shaft 8 Transmission mechanism 9 Drive motor 12 Battery 20 Integrated controller unit 20A Overrotation prevention processing unit 20Aa Overrotation prevention control unit 20Ab Return control Part 21 engine control part 22 motor / generator control part 23 clutch control part 30 accelerator sensor 31 wheel speed sensor 32 brake sensor 33 battery sensor CL1, CL2 clutch (power interrupting mechanism)

Claims (8)

An engine connected to the drive wheel via a planetary gear mechanism, a first electric motor connected to the engine and the drive wheel via the planetary gear mechanism, a second electric motor connected to the drive wheel,
A power interrupting mechanism for switching between a power transmission state and a non-power transmission state with respect to a connection state of the engine, the first motor, and the second motor to the drive wheel;
When it is determined that the change in the rotational speed of the drive wheel is greater than a predetermined value, over-rotation prevention is performed to switch the connection state of the engine, the first motor, and the second motor to the drive wheel to the non-power transmission state via the power interrupt mechanism. Means,
If it is determined that the rotational speed change of the drive wheel is larger than a predetermined value, the rotational speed control means for controlling the rotational speed of the first electric motor and the second electric motor;
A drive control apparatus for a hybrid vehicle, comprising:   The rotational speed control means sets the target rotational speed of the rotational speed control to the over-rotation prevention when the speed change of the vehicle speed after determining that the rotational speed change of the drive wheel is larger than a predetermined value. 2. The drive control apparatus for a hybrid vehicle according to claim 1, wherein the rotational speed is set to a non-power transmission state by means.   The rotation speed control means, when determining that the rotation speed of the first motor or the second motor is an excessive rotation speed, lowers the target rotation speed of the rotation speed control in the motor determined to be the excessive rotation speed. A drive control apparatus for a hybrid vehicle according to claim 1 or 2. A common battery electrically connected to the first motor and the second motor;
The rotation speed control means controls the rotation speed of the first motor and the second motor so that the total amount of power generation and the total amount of power consumption in the first motor and the second motor are equal to each other. The drive control apparatus of the hybrid vehicle described in any one of Claims 1-3. A transmission mechanism interposed in the middle of the power transmission path from the engine, the first electric motor, and the second electric motor to the drive wheel, and having a plurality of shift stages;
Driving force request detecting means for detecting presence or absence of a driving force request by the driver;
If it is determined that there is a driving force request by the driver in the state where the over-rotation preventing means is switched to the non-power transmission state, the speed change mechanism is set to a gear position corresponding to the vehicle speed, Over-rotation prevention process ending means for switching the connection state of the electric motor and the second electric motor to the power transmission state;
The drive control apparatus for a hybrid vehicle according to any one of claims 1 to 4, further comprising: Vehicle speed estimation means for estimating the vehicle speed;
An estimated vehicle speed validity determining means for determining whether or not the estimated vehicle speed deviates from the actual vehicle speed,
6. The hybrid vehicle drive according to claim 5, wherein when the estimated vehicle speed deviates from the actual vehicle speed, the over-rotation prevention process ending means sets the speed change mechanism to a state with the smallest reduction ratio. Control device. A driving force request detecting means for detecting the presence or absence of a driving force request by the driver;
If the over-rotation prevention means determines that there is no driving force request from the driver, the power interrupting mechanism that has switched to the non-power transmission state is switched to the power transmission state in a non-power transmission state where the return time for switching to the power transmission state is short. The drive control device for a hybrid vehicle according to any one of claims 1 to 6, wherein the drive control device is set to a standby state. An engine connected to the drive wheel via a planetary gear mechanism; a first electric motor connected to the engine and the drive wheel via the planetary gear mechanism; a second electric motor connected to the drive wheel; an engine for the drive wheel; A power interrupting mechanism that switches between a power transmission state and a non-power transmission state for a connection state of the first motor and the second motor;
If it is determined that the rotational speed change of the drive wheel is greater than a predetermined value, the connection state of the engine, the first motor, and the second motor to the drive wheel is switched to the non-power transmission state via the power intermittent mechanism, and the first A drive control method for a hybrid vehicle, characterized in that the electric motor and the second electric motor are controlled in rotation speed.

Images