JP2006017042A - Engine speed control device for hybrid vehicle and its engine speed control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an engine speed control device for a hybrid vehicle and its engine speed control method, for smoothly transit modes between an electric vehicle running mode by releasing an engine clutch and a hybrid vehicle running mode by engaging the engine clutch so that a driver does not feel discomfort. <P>SOLUTION: The hybrid vehicle comprises: an engine E and a motor functioning as a driving force generating source; a driving force synthesizing transmission TG connecting the engine E, the motor, and an output member; and an integral controller 6 for performing a cooperative control of the engine E and the motor. An engine clutch EC is disposed between the engine E and driving force synthesizing transmission TG, and the integral controller 6 performs a speed control of the engine E in each case of the engagement or release for the engine clutch EC. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an engine speed control device and an engine speed control method for a hybrid vehicle using an engine and a motor as driving force generation sources.

A conventional engine speed control device for a hybrid vehicle using an engine and a motor as a driving force generation source uses the motor torque connected to the engine as an estimated torque value of the engine, and corrects the engine output from the difference from the target torque of the engine. (For example, refer to Patent Document 1).
Japanese Patent No. 3395708

  However, in the prior art, in a hybrid vehicle, it is common to perform torque control on the engine, and since there is no engine clutch, there is no need to separate the engine and rotate the engine alone (always a certain amount of load is applied). Therefore, there was no problem with torque control.

  On the other hand, in the case of a hybrid vehicle with an engine clutch and having an electric vehicle traveling mode and a hybrid vehicle traveling mode, when the engine clutch is disengaged, it becomes difficult to control the engine torque because the engine load becomes zero. . To avoid this, it is conceivable to control the engine speed only when the engine clutch is disconnected. However, switching of the engine control method occurs, and if the control is not successful, the driver may feel uncomfortable when switching the control. .

  The present invention has been made paying attention to the above-mentioned problem, and the driver feels uncomfortable at the time of mode transition between the electric vehicle traveling mode by releasing the engine clutch and the hybrid vehicle traveling mode by engaging the engine clutch. An object of the present invention is to provide an engine speed control device and an engine speed control method for a hybrid vehicle that can achieve smooth mode transition without giving them.

In order to achieve the above object, in the engine speed control device and the engine speed control method for a hybrid vehicle according to the present invention, the driving force generating source includes an engine and a motor, and the engine, the motor, and the output member are connected. In a hybrid vehicle comprising a composite transmission and an integrated controller that performs cooperative control of the engine and motor,
An engine clutch is provided between the engine and the driving force synthesis transmission,
The integrated controller performs engine speed control regardless of whether the engine clutch is engaged or disengaged.

  Therefore, in the engine speed control device for a hybrid vehicle of the present invention, the engine speed control is performed in the integrated controller regardless of whether the engine clutch is engaged or disengaged. A smooth mode transition that does not give the driver a sense of incongruity can be achieved during the mode transition between the electric vehicle traveling mode and the hybrid vehicle traveling mode by engagement of the engine clutch.

  Hereinafter, the best mode for realizing an engine speed control device for a hybrid vehicle according to the present invention will be described based on a first embodiment shown in the drawings.

First, the drive system configuration of the hybrid vehicle will be described.
FIG. 1 is an overall system diagram showing a drive system of a hybrid vehicle to which the engine speed control device of the first embodiment is applied. As shown in FIG. 1, the drive system of the hybrid vehicle in the first embodiment includes an engine E, a first motor generator MG1 (motor), a second motor generator MG2 (motor), and an output gear OG (output member). And a driving force synthesis transmission TM.

  The engine E is a gasoline engine or a diesel engine, and the opening degree of a throttle valve and the like are controlled based on a target engine torque command from an engine controller 1 described later.

  The first motor generator MG1 and the second motor generator MG2 are synchronous motor generators in which a permanent magnet is embedded in a rotor and a stator coil is wound around a stator. Based on a control command from a motor controller 2 described later, an inverter 3 are controlled independently by applying the three-phase alternating current generated by 3.

  The driving force combined transmission TM includes a Ravigneaux type planetary gear train PGR and a low brake LB, and the Ravigneaux planetary gear train PGR includes a first sun gear S1, a first pinion P1, and a first ring gear. R1, the second sun gear S2, the second pinion P2, the second ring gear R2, and the common carrier PC that supports the first pinion P1 and the second pinion P2 that mesh with each other. That is, the Ravigneaux type planetary gear PGR has five rotating elements: the first sun gear S1, the first ring gear R1, the second sun gear S2, the second ring gear R2, and the common carrier PC. The connection relationship of the input / output members with respect to these five rotating elements will be described.

  A first motor generator MG1 is connected to the first sun gear S1. The first ring gear R1 is provided so as to be fixed to the case via a low brake LB. A second motor generator MG2 is connected to the second sun gear S2. An engine E is connected to the second ring gear R2 via an engine clutch EC. An output gear OG is directly connected to the common carrier PC. A driving force is transmitted from the output gear OG to the left and right driving wheels via a differential and a drive shaft (not shown).

2, the first motor generator MG1 (first sun gear S1), engine E (second ring gear R2), output gear OG (common carrier PC), low brake LB (first It is possible to introduce a rigid lever model that is arranged in the order of 1 ring gear R1) and second motor generator MG2 (second sun gear S2) and can simply express the dynamic operation of the Ravigneaux planetary gear train PGR.
Here, the “collinear diagram” is a velocity diagram used in a simple and easy-to-understand method of drawing instead of the method of obtaining by equation when considering the gear ratio of the differential gear, The rotation number (rotation speed) of the rotation element is taken, each rotation element is taken on the horizontal axis, and the interval between each rotation element is arranged so as to be a collinear lever ratio based on the gear ratio of the sun gear and the ring gear. .

  The engine clutch EC and the low brake LB are a multi-plate friction clutch and a multi-plate friction brake that are fastened by hydraulic pressure from a hydraulic control device 5 to be described later. The engine clutch EC is the engine clutch on the collinear diagram of FIG. The low brake LB is arranged at a position that coincides with the rotational speed axis of the second ring gear R2 together with E, and the low brake LB is arranged on the nomographic chart of FIG. 2 at a position between the rotational speed axis of the sun gear S2.

Next, the control system of the hybrid vehicle will be described.
As shown in FIG. 1, the hybrid vehicle control system in the first embodiment includes an engine controller 1, a motor controller 2, an inverter 3, a battery 4, a hydraulic control device 5, an integrated controller 6, and an accelerator opening. A sensor 7, a vehicle speed sensor 8, an engine speed sensor 9, a first motor generator speed sensor 10, a second motor generator speed sensor 11, and a second ring gear speed sensor 12 are configured. Has been.

  The engine controller 1 responds to a target engine torque command from the integrated controller 6 that inputs the accelerator opening AP from the accelerator opening sensor 7 and the engine speed Ne from the engine speed sensor 9, in accordance with the engine operating point (Ne, A command for controlling Te) is output to, for example, a throttle valve actuator (not shown).

  The motor controller 2 operates the motor of the first motor generator MG1 in response to a target motor generator torque command from the integrated controller 6 that inputs motor generator rotation speeds N1 and N2 from both motor generator rotation speed sensors 10 and 11 by a resolver. A command (device control signal) for independently controlling the point (N1, T1) and the motor operating point (N2, T2) of the second motor generator MG2 is output to the inverter 3. The motor controller 2 outputs information on the battery S.O.C representing the state of charge of the battery 4 to the integrated controller 6.

  The inverter 3 is connected to the respective stator coils of the first motor generator MG1 and the second motor generator MG2, and generates an independent three-phase alternating current according to a command from the motor controller 2. The inverter 3 is connected to a battery 4 that is discharged during power running and charged during regeneration.

  The hydraulic control device 5 receives a hydraulic pressure command from the integrated controller 6 and performs engagement hydraulic pressure control and release hydraulic pressure control of the engine clutch EC and the low brake LB. The engagement hydraulic pressure control and the release hydraulic pressure control include a half-clutch control based on a slip engagement control and a slip release control.

  The integrated controller 6 includes an accelerator opening AP from the accelerator opening sensor 7, a vehicle speed VSP from the vehicle speed sensor 8, an engine speed Ne from the engine speed sensor 9, and a first motor generator speed sensor 10. Information such as the first motor generator rotational speed N1, the second motor generator rotational speed N2 from the second motor generator rotational speed sensor 11, and the engine input rotational speed ωin from the second ring gear rotational speed sensor 12. Predetermined arithmetic processing is performed. Then, a control command is output to the engine controller 1, the motor controller 2, and the hydraulic control device 5 according to the calculation processing result.

  The integrated controller 6 and the engine controller 1 and the integrated controller 6 and the motor controller 2 are connected by bidirectional communication lines 14 and 15 for information exchange, respectively.

Next, the travel mode of the hybrid vehicle will be described.
The travel modes in the hybrid vehicle of the first embodiment include an electric vehicle continuously variable transmission mode (hereinafter referred to as “EV mode”), an electric vehicle fixed transmission mode (hereinafter referred to as “EV-LB mode”), and a hybrid. It has a vehicle fixed speed change mode (hereinafter referred to as “LB mode”) and a hybrid vehicle continuously variable speed change mode (hereinafter referred to as “E-iVT mode”). The “EV mode” and the “EV-LB mode” are “electric vehicle travel mode”, and the “LB mode” and the “E-iVT mode” are “hybrid vehicle travel mode”.

  The “EV mode” is a continuously variable transmission mode in which only two motor generators MG1 and MG2 run as shown in the collinear diagram of FIG. 2 (a), and the engine E is driven (minimum speed control). The engine clutch EC is released.

  The “EV-LB mode” is a fixed speed change mode in which only the two motor generators MG1 and MG2 run with the low brake LB engaged, as shown in the collinear diagram of FIG. E is drive (minimum speed control) and the engine clutch EC is released. Since the reduction ratio from the first motor generator MG1 to the output Output and the reduction ratio from the second motor generator MG2 to the output Output are large, this is a mode in which a large driving force is generated.

  As shown in the collinear diagram of FIG. 2 (c), the “LB mode” is a fixed speed change mode in which the engine E and the motor generators MG1 and MG2 travel with the low brake LB engaged. The engine clutch EC is engaged during operation. This is a mode in which the driving force is large because the reduction ratio from the engine E and the motor generators MG1, MG2 to the output Output is large.

  The “E-iVT mode” is a continuously variable transmission mode in which the engine E and the motor generators MG1 and MG2 run as shown in the nomogram of FIG. 2 (d). The engine E is operated and the engine clutch EC is It is conclusion.

  Then, the mode transition control of the four travel modes is performed by the integrated controller 6. That is, the integrated controller 6 has a travel mode in which the four travel modes as shown in FIG. 3 are allocated to the three-dimensional space by the required driving force Fdrv (determined by the accelerator opening AP), the vehicle speed VSP, and the battery SOC. When the vehicle is stopped or running, the driving mode map is searched based on the detected values of the required driving force Fdrv, vehicle speed VSP, and battery SOC, and the vehicle operating point determined by the required driving force Fdrv and vehicle speed VSP. The optimum driving mode is selected according to the battery charge amount. FIG. 3 is an example of a travel mode map represented by a two-dimensional representation of the required driving force Fdrv and the vehicle speed VSP by cutting out the three-dimensional travel mode map at a value with a sufficient capacity range of the battery S.O.C.

  When mode transition is performed between the “EV mode” and the “EV-LB mode” by selecting the travel mode map, the low brake LB is engaged / released as shown in FIG. When mode transition is performed between the “E-iVT mode” and the “LB mode”, the low brake LB is engaged / released as shown in FIG. Further, when the mode transition is performed between the “EV mode” and the “E-iVT mode”, the engagement / release of the engine clutch EC is performed as shown in FIG. When mode transition is performed between the “EV-LB mode” and the “LB mode”, the engine clutch EC is engaged / released as shown in FIG.

FIG. 5 is a control block diagram illustrating an engine speed control system of the engine speed control apparatus according to the first embodiment.
When the engine clutch EC is engaged, the integrated controller 6 calculates a target engine speed calculating unit 6a that calculates a target engine speed required to maintain at least the required gear ratio based on the vehicle speed VSP and the accelerator pedal opening AP, A torque command value setting unit 6b for calculating a target engine torque command value based on a deviation between the engine speed and the actual engine speed. The target rotational speed calculation unit 6a calculates the target engine rotational speed required for performing the self-sustaining rotation when the engine clutch EC is released. That is, information on the minimum number of revolutions required for the engine E to maintain its rotation is received from the engine controller 1 and the engine revolution number is controlled to be equal to or higher than the minimum revolution number. Then, the amount of torque provided to maintain the engine speed at a predetermined speed equal to or higher than the minimum speed is given as a subsequent compensation amount.

  When the target engine torque command value calculated by the torque command value setting unit 6b is transmitted to the engine controller 1, the engine controller 1 receives the target engine torque command value and the actual engine speed from the integrated controller 6. The throttle opening of the engine E is set using a map or the like.

  A series of these controls, that is, by instructing the target engine torque to the engine controller 1 so that the actual engine speed follows the target engine speed calculated inside the integrated controller 6, The engine E speed control performed in any case of release is realized.

FIG. 6 is a control block diagram showing a torque command value setting unit 6b for setting a target engine torque command value in the engine speed control device of the first embodiment.
The torque command value setting unit 6b includes a NOT circuit 60, an AND circuit 61, a switching device 62, a subtractor 63, an integral term computing unit 64, a proportional term computing unit 65, an adder 66, an engine rotation. A number control gain setting unit 67.

The NOT circuit 60 inputs a “0” signal and outputs a “1” signal before the clutch engagement is completed, and inputs a “1” signal and outputs a “0” signal after the clutch engagement is completed. To do. When the AND circuit 61 inputs a signal “1” after the clutch-on request is started and simultaneously inputs a signal “1” from the NOT circuit 60, the AND circuit 61 moves the switch 62 from the “0” side to the “1” side. Switch to.
That is, when performing engine speed control by proportional / integral control, the torque command value setting unit 6b selects and integrates “0” only during the transition from the engagement request of the engine clutch EC to the completion of engagement of the engine clutch EC. Stop the control amount.

The subtracter 63 subtracts the actual engine speed obtained by the engine controller 1 from the target engine speed obtained by the target speed calculator 6a to obtain an engine speed deviation. The integral term computing unit 64 computes an integral term of 0 when the switcher 62 selects the “0” side, and engine rotation when the switcher 62 selects the “1” side. Calculate the value of the integral term based on the number deviation. The proportional term calculator 65 always calculates the value of the proportional term based on the engine speed deviation regardless of the selection position of the switch 62. The adder 66 adds the value of the integral term from the integral term calculator 64 and the value of the proportional term from the proportional term calculator 65. The engine speed control gain setting unit 67 obtains a target engine torque command value by multiplying the addition value of the proportional term and the integral term from the adder 66 by the engine speed control gain K, and obtains the target engine torque command value. Output to.
That is, the torque command value setting unit 6b sets the engine speed control gain K when the engine clutch EC is released to the same value as the engine speed control gain K when the engine clutch EC is engaged.

Next, the operation will be described.
[Challenges for hybrid vehicles with engine clutch]
In a hybrid vehicle in which the engine is disconnected from the motor by the engine clutch, engine torque cannot be sensed when the engine clutch is released (during driving in the electric vehicle driving mode). The approximate engine torque is estimated from a map conversion value from the cylinder air amount calculated in the above.

  However, the difference between the actual torque and the estimated torque value due to deterioration with time cannot be corrected, and some complementation is required between the grid points of the map, so that the engine torque cannot be estimated with high accuracy.

  In addition, because the engine controller, because of the control configuration, almost always supplies the air amount necessary for maintaining stable rotation in the vicinity of idle rotation with a feedforward element such as a map conversion value, the estimated torque value and the actual torque value If the shift occurs, the followability to the target rotational speed is deteriorated accordingly.

  The engine is driven at idle rotation in the “electric vehicle running mode” in which the engine is separated from the motor by the engine clutch, as well as in the “electric vehicle running mode” in which the engine is separated from the motor by the engine clutch. Even in this case, the estimation accuracy of the engine torque is lowered. Therefore, when the engine clutch is engaged from the “electric vehicle travel mode” and the mode transition is made to the “hybrid vehicle travel mode” in which the engine is added to the power source, the target engine speed and torque cannot be obtained or the target The followability with respect to the rotational speed is deteriorated, and there is a problem that the driver feels uncomfortable due to engine torque fluctuation and rotational speed fluctuation at the time of mode transition.

[Engine speed control action]
On the other hand, in the engine speed control of the first embodiment, by commanding the target engine torque to the engine controller 1 so that the actual engine speed follows the target engine speed calculated inside the integrated controller 6. In addition, the engine E rotation speed control is performed in both cases where the engine clutch EC is engaged or disengaged, so that the electric vehicle traveling mode when the engine clutch EC is disengaged and the hybrid vehicle traveling mode when the engine clutch EC is engaged. During the mode transition between and, smooth mode transition was achieved without giving the driver a sense of incongruity.

Hereinafter, as an example of the mode transition in which the engagement / release of the engine clutch EC is performed, the engine speed control operation at the time of the mode transition from the “EV mode” to the “E-iVT mode” will be described.
First, while the engine clutch EC is running in the “EV mode” with the released state and the engine clutch EC is requested to be engaged, the actual engine speed is set to the target engine speed calculated in the integrated controller 6. By commanding the target engine torque to the engine controller 1 so that the number follows, the rotational speed control of the engine E is performed by proportional / integral control.

  That is, the target engine speed calculation unit 6a of the integrated controller 6 calculates the target engine speed required for performing independent rotation, and based on the deviation between the target engine speed and the actual engine speed, the torque command value setting unit The target engine torque command value is calculated in 6b, and the engine controller 1 receives the target engine torque command value and the actual engine speed from the integrated controller 6, and sets the throttle opening of the engine E using a map or the like.

Here, in the released state of the engine clutch EC, information on the minimum number of revolutions necessary for the engine E to maintain the rotation is received from the engine controller 1, and the engine revolution number is set to the minimum revolution number in the same manner as the idle revolution number control. Control above. Then, the amount of torque provided to maintain the engine speed at a predetermined speed equal to or higher than the minimum speed is given as a subsequent compensation amount.
Note that the gear ratio in the “EV mode” is performed by motor generator rotation speed control by the first motor generator MG1 and the second motor generator MG2.

  Next, during the period of travel in the “EV mode”, after the engine clutch EC engagement request is issued and until the engine clutch EC engagement is completed, the target engine speed calculated inside the integrated controller 6 is By commanding the target engine torque to the engine controller 1 so that the engine speed follows, the speed control of the engine E is performed only by proportional control.

  Here, integral control is performed only during the transition from the engagement request of the engine clutch EC to the completion of the engagement of the engine clutch EC, even though the engine speed control is performed by proportional / integral control until the engagement request of the engine clutch EC is issued. Even if there is a momentary disturbance in the engine speed due to the engagement of the engine clutch EC, etc. in order to stop the amount, there will be no excess manipulated variable after the occurrence of the disturbance. Can be controlled.

  Next, after the engagement of the engine clutch EC is completed, when the mode transition is made to the “E-iVT mode”, the actual engine speed follows the target engine speed calculated inside the integrated controller 6. By commanding the target engine torque to the engine controller 1, the rotational speed control of the engine E is performed by proportional / integral control.

  That is, the target engine speed calculation unit 6a of the integrated controller 6 calculates at least the target engine speed required to maintain the required gear ratio, and sets the torque command value based on the deviation between the target engine speed and the actual engine speed. The engine controller 1 calculates the target engine torque command value in the unit 6b, and the engine controller 1 receives the target engine torque command value and the actual engine speed from the integrated controller 6, and sets the throttle opening of the engine E using a map or the like. .

Here, since the engine speed control gain K in the released state of the engine clutch EC is set to be the same as the engine speed control gain K in the engaged state of the engine clutch EC, the engine clutch EC shifts from released to engaged. In other words, when the mode is changed from the “EV mode” to the “E-iVT mode”, fluctuations in the rotation of the engine E can be suppressed, and the speed ratio can be stabilized.
Although explanation is omitted, similarly, when the mode is changed from the “E-iVT mode” to the “EV mode”, the rotational fluctuation of the engine E can be suppressed and the speed ratio can be stabilized.

Next, the effect will be described.
The effects listed below can be obtained in the engine speed control device and the engine speed control method for the hybrid vehicle of the first embodiment.

  (1) A driving force synthesis transmission TG having an engine E and a motor as a driving force generation source, connecting the engine E, the motor, and an output member; an integrated controller 6 that performs cooperative control of the engine E and the motor; In the hybrid vehicle having the engine E, an engine clutch EC is provided between the engine E and the driving force synthesizing transmission TG, and the integrated controller 6 controls the engine E regardless of whether the engine clutch EC is engaged or disengaged. Because the engine speed is controlled, the driver feels uncomfortable at the time of mode transition between the “electric vehicle running mode” by releasing the engine clutch EC and the “hybrid vehicle running mode” by engaging the engine clutch EC. A smooth mode transition can be achieved. In addition, since the rotational speed control of the engine E is performed in the integrated controller 6, other control logic such as the rotational speed control of the motor generators MG1 and MG2 can be used.

  (2) The integrated controller 6 controls the rotational speed of the engine E by instructing the target torque to the engine controller 1 so that the actual engine rotational speed follows the target engine rotational speed calculated internally. Since the logic of the engine controller 1 can remain the existing logic and the engine speed can be changed, the number of development man-hours required for the specification change can be minimized.

  (3) The driving force synthesizing transmission TG sets the transmission ratio by the engine E and the motor, and the integrated controller 6 determines the engine torque required for the self-rotation when the engine clutch EC is released. When the engine clutch EC is engaged, the engine torque required to maintain at least the required gear ratio is calculated. Therefore, regardless of whether the engine clutch EC is engaged or released, the engine is operated with the same logic in any case. Rotational speed control can be performed, and the development man-hour required for creating the engine rotational speed control logic can be minimized.

  (4) The integrated controller 6 sets the engine speed control gain K when the engine clutch EC is released to the same value as the engine speed control gain K when the engine clutch EC is engaged. Since the engine speed EC gain K does not change during release and release of the engine clutch EC → engagement, fluctuations in the engine speed at the time of switching between engagement / release of the engine clutch EC can be suppressed.

  (5) When the engine speed is controlled by proportional / integral control, the integrated controller 6 stops the integral control amount only during the transition from the engagement request of the engine clutch EC to the completion of the engagement of the engine clutch EC. Even when an external disturbance occurs instantaneously in the engine speed due to the engagement of the engine clutch EC, etc., since there is no extra operation amount after the occurrence of the disturbance, the same control as before the occurrence of the disturbance can be performed after the occurrence of the disturbance. .

  (6) The integrated controller 6 receives information on the minimum number of revolutions necessary for the engine E to maintain its rotation from the engine controller 1 and controls the engine revolution number to be equal to or higher than the minimum revolution number. Since the engine speed is controlled by the integrated controller 6 while making use of a necessary part of the function (idle stop control function), the existing logic and the new logic can be optimally integrated.

  (7) The integrated controller 6 provides an ISC function (idle stop control function) of the engine E in order to give the amount of torque that is provided to maintain the engine speed at a predetermined speed equal to or higher than the minimum speed as a subsequent compensation amount. The amount of torque deviation that cannot be set in the above can be added as a compensation amount, and the followability to the target engine speed and the accuracy can be improved.

  (8) In the driving force synthesis transmission TG, four or more rotating elements are arranged on a collinear diagram, and one of the two rotating elements arranged inside each rotating element is connected to an engine clutch EC. And assigning an input from the engine E to the other of the two rotating elements, and assigning an output gear OG to the drive system to each other, and the first motor generator to each of the two rotating elements arranged on both outer sides of the inner rotating element It has a Ravigneaux type planetary gear train PGR in which MG1 and the second motor generator MG2 are connected, and the integrated controller 6 outputs a command for engaging / disengaging the engine clutch EC, and both motor generators MG1, MG2 by cooperative control And a target torque command value for the engine E are calculated and output to the motor controller 2 and the engine controller 1, respectively. Smooth mode that does not give the driver a sense of incongruity when switching between EV mode and E-iVT mode in hybrid vehicles that have EV mode and E-iVT mode Transitions can be achieved.

  (9) a driving force synthesis transmission TG having an engine E and a motor as a driving force generation source, connecting the engine E, the motor, and an output member; an integrated controller 6 that performs cooperative control of the engine E and the motor; In the hybrid vehicle having the engine E, an engine clutch EC is provided between the engine E and the driving force synthesizing transmission TG, and the integrated controller 6 controls the engine E regardless of whether the engine clutch EC is engaged or disengaged. Because the engine speed is controlled, the driver feels uncomfortable at the time of mode transition between the “electric vehicle running mode” by releasing the engine clutch EC and the “hybrid vehicle running mode” by engaging the engine clutch EC. It is possible to provide a method for controlling the engine speed of a hybrid vehicle that achieves smooth mode transition without any problems.

  As mentioned above, although the engine speed control apparatus of the hybrid vehicle of this invention was demonstrated based on Example 1, it is not restricted to this Example 1 about a concrete structure, Each claim of a claim Design changes and additions are permitted without departing from the spirit of the invention.

  In the first embodiment, an example of a hybrid vehicle with an engine clutch having an engine and two motor generators as a driving force generation source is shown. However, a parallel type with an engine clutch having an engine and one or more motors as a driving force generation source is shown. Applicable to hybrid vehicles. Moreover, although the example which has a Ravigneaux type planetary gear train as a driving force synthetic | combination transmission was shown, for example, it can apply also to the driving force synthetic | combination transmission which has a differential apparatus etc. provided with several simple planetary gear trains. .

1 is an overall system diagram showing a hybrid vehicle to which an engine speed control device of Embodiment 1 is applied. It is a collinear diagram showing each traveling mode by the Ravigneaux type planetary gear train adopted in the hybrid vehicle to which the engine speed control device of the first embodiment is applied. It is a figure which shows an example of the driving mode map in the hybrid vehicle to which the engine speed control apparatus of Example 1 was applied. It is a figure which shows the mode transition path | route between four driving modes in the hybrid vehicle to which the engine speed control apparatus of Example 1 was applied. FIG. 2 is a control block diagram illustrating an engine speed control system of the engine speed control device according to the first embodiment. It is a control block diagram which shows the torque command value setting part which sets a target engine torque command value with the engine speed control apparatus of Example 1. FIG.

Explanation of symbols

E engine
MG1 1st motor generator (motor)
MG2 Second motor generator (motor)
OG output gear (output member)
TM Driving force transmission
PGR Ravigneaux type planetary gear train
EC engine clutch
LB Low brake 1 Engine controller 2 Motor controller 3 Inverter 4 Battery 5 Hydraulic control device 6 Integrated controller 6a Target rotational speed calculation section 6b Torque command value setting section 7 Accelerator opening sensor 8 Vehicle speed sensor 9 Engine rotational speed sensor 10 First motor generator Speed sensor 11 Second motor generator speed sensor 12 Second ring gear speed sensor

Claims (9)

In a hybrid vehicle comprising an engine and a motor as driving force generation sources, a driving force combining transmission that connects the engine, the motor, and an output member, and an integrated controller that performs cooperative control of the engine and the motor,
An engine clutch is provided between the engine and the driving force synthesis transmission,
The engine speed control device for a hybrid vehicle, wherein the integrated controller controls the engine speed regardless of whether the engine clutch is engaged or disengaged. In the hybrid vehicle engine speed control device according to claim 1,
The hybrid controller performs engine speed control by instructing a target engine torque to the engine controller so that the actual engine speed follows the target engine speed calculated internally. Engine speed control device. In the engine speed control device for a hybrid vehicle according to claim 1 or 2,
The driving force synthesizing transmission sets a gear ratio by an engine and a motor,
When the engine clutch is disengaged, the integrated controller calculates the target engine speed required to perform self-sustaining rotation, and when the engine clutch is engaged, calculates the target engine speed required to maintain at least the required gear ratio. An engine speed control device for a hybrid vehicle. The engine speed control device for a hybrid vehicle according to any one of claims 1 to 3,
The integrated controller sets an engine speed control gain when the engine clutch is released to be the same as an engine speed control gain when the engine clutch is engaged. The engine speed control device for a hybrid vehicle according to any one of claims 1 to 4,
When the engine speed is controlled by proportional / integral control, the integrated controller stops the integral control amount only during the transition from the engagement request of the engine clutch to the completion of the engagement of the engine clutch. Engine speed control device. In the engine speed control device for a hybrid vehicle according to any one of claims 1 to 5,
The integrated controller receives information on a minimum number of revolutions necessary for the engine to maintain its rotation from the engine controller, and controls the engine revolution number to be equal to or higher than the minimum revolution number. apparatus. In the hybrid vehicle engine rotational speed control device according to claim 6,
The integrated controller provides an engine speed control device for a hybrid vehicle, which provides a compensation amount for a torque that is provided to maintain the engine speed at a predetermined speed equal to or higher than the minimum speed. The engine speed control device for a hybrid vehicle according to any one of claims 1 to 7,
In the driving force combining transmission, four or more rotating elements are arranged on a collinear diagram, and one of two rotating elements arranged inside each rotating element is input from an engine via an engine clutch. An output member to the drive system is assigned to the other of the two rotating elements, and the first motor generator and the second motor generator are respectively assigned to the two rotating elements arranged on both outer sides of the inner rotating element. It has a connected Ravigneaux planetary gear train,
The integrated controller outputs a command for engaging / disengaging the engine clutch, calculates a target torque command value for both motor generators and the engine by cooperative control, and outputs each command value to the motor controller and the engine controller. An engine speed control device for a hybrid vehicle characterized by the above. In a hybrid vehicle comprising an engine and a motor as a driving force generation source, a driving force combining transmission that connects the engine and the motor, and an integrated controller that performs cooperative control of the engine and the motor,
An engine clutch is provided between the engine and the driving force synthesis transmission,
The method for controlling the engine speed of a hybrid vehicle, wherein the integrated controller controls the engine speed regardless of whether the engine clutch is engaged or disengaged.

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