WO2006048968A1

WO2006048968A1 - Drive device for hybrid vehicle and control method for the same

Info

Publication number: WO2006048968A1
Application number: PCT/JP2005/015897
Authority: WO
Inventors: Yasuhiko Kobayashi
Original assignee: Aisin Aw Co., Ltd.
Priority date: 2004-11-04
Filing date: 2005-08-31
Publication date: 2006-05-11
Also published as: CN101031460A; DE112005002385B4; DE112005002385T5; CN101031460B; JP4135107B2; JP2006131037A

Abstract

A drive device for a hybrid vehicle, with which an engine can be started in a short time, regardless of the operating state of the vehicle including the number of rotation of a motor, in response to an engine start request while the vehicle is traveling by the drive force of the motor, and a control method for the drive device. The drive device comprises a motor, a first clutch for making or interrupting the transmission of drive force between the motor and an engine, a second clutch for making or interrupting the transmission of drive force of either or both of the motor and the engine to the wheel side, and a controller for performing operation control of the motor, the first clutch, and the second clutch. When engine start is requested while wheels are driven by the motor, the controller performs operation control of the motor, the first clutch, and the second clutch according to a control pattern dependent on the number of rotation of the motor which is detected directly or indirectly.

Description

, Driving device for hybrid vehicle and control method thereof

Technical field

The present invention relates to a drive device mounted on a hybrid vehicle that travels using both an engine and a motor, and a control method therefor.

Background art

[0002] As a technology related to control at the time of engine start in a drive device mounted on a hybrid vehicle that travels using both an engine and a motor, for example, the following technology is described in Patent Document 1 below. Yes. This technology uses a motor to maintain a smooth vehicle response to the driver's request using a motor in a parallel type hybrid vehicle drive system with an engine separation clutch, and starts the engine by engaging the engine separation clutch. This is a control technology that allows the motor to follow the speed of the torque that is necessary to obtain the desired set speed ^ Controlled in control mode. That is, when the engine is started, first, an engine separation clutch is fastened, a desired speed is commanded to the motor, fuel is supplied to the engine, and the engine is started. After that, calculate the desired engine 'torque, and while maintaining the vehicle speed using, for example, a proportional integral controller, gradually reduce the motor torque until the motor torque becomes zero, and proportionally engine' torque To increase the control.

[0003] Here, the setting of the desired speed of the motor is based on the operation state of the entire vehicle and the driver's request, and is either a trajectory based on the vehicle speed and acceleration at the present time and at a past time, or a constant value. Can be. On the other hand, if the driver is not currently commanding the operating torque and a power transmission unit such as an automatic transmission that transmits the driving force of the engine and motor power to the wheels is not coupled, the desired set speed is Set to the desired idle speed of the engine.

[0004] Patent Document 1: Japanese Patent Laid-Open No. 2003-129926 (Pages 1-5, Fig. 1-2)

Disclosure of the invention

Problems to be solved by the invention

[0005] While driving, the hybrid vehicle drive apparatus as described above is The control technology has the following problems. In other words, when the power transmission unit is coupled and there is a request for starting the engine while the vehicle is driven by the driving force of the motor, it is preferable to start the engine depending on the operating state of the vehicle including the number of rotations of the motor. May not be possible. In other words, in order to start the engine, it is necessary to rotate the crankshaft of the engine at a certain rotational speed. However, for example, when the vehicle is running with the driving force of the motor in a state where the power transmission unit is coupled and the vehicle speed is low, the above control technique allows the motor to rotate according to the vehicle speed. The number is controlled low. Therefore, if the motor rotation speed is lower than the engine rotation speed, there is a problem that the engine cannot be started immediately at the vehicle speed.

Means for solving the problem

[0006] The present invention has been made in view of the above problems, and an object of the present invention is to provide a vehicle including the number of rotations of the motor when there is an engine start request during traveling of the vehicle by the driving force of the motor. The object of the present invention is to provide a hybrid vehicle drive device and a control method thereof capable of starting the engine in a short time regardless of the operating state.

[0007] To achieve the above object, the hybrid vehicle drive device according to the present invention includes a motor, a first clutch that transmits or disconnects a driving force between the motor and the engine, and the motor. And a second clutch that transmits or disconnects the driving force of one or both of the engines to the wheel side, and a control device that controls the operation of the motor, the first clutch, and the second clutch, When there is an engine start request during driving of the wheel by the motor, the control device is configured to control the motor, the first control unit, or the like according to a control pattern that differs depending on the rotational speed of the motor detected directly or indirectly. The operation of the one clutch and the second clutch is controlled, and the engine is started.

[0008] According to this characteristic configuration, when there is an engine start request during driving of the wheels by the motor, the operation of the motor, the first clutch, and the second clutch is controlled by a different control pattern according to the number of rotations of the motor. It will be. Therefore, an optimal control pattern can be applied according to the vehicle operating state including the motor speed, and the engine can be reliably started in a short time. Here, the control device has at least two types of control patterns, that is, a control pattern for high rotation and a control pattern for low rotation as the control pattern, and the control pattern for high rotation The control pattern is to start the engine by increasing the engagement pressure of the first clutch with the two clutches fully engaged, and the low-rotation control pattern is the control pattern with the second clutch open. A configuration in which the engine is started by increasing the engagement pressure of the first clutch can also be adopted.

[0010] By using two control patterns for high rotation and low rotation in this way, a simple control algorithm can be used in a short time according to the operating state of the vehicle including the motor speed. The engine can be reliably started.

[0011] Further, the control device is configured to perform the high rotation when the rotation speed of the motor is equal to or higher than a threshold value set to be equal to or higher than a rotation speed at which the engine can be started with the first clutch engaged. It is preferable to perform control for selecting the control pattern for low rotation and selecting the control pattern for low rotation when the control pattern is less than the threshold value.

[0012] With this, when there is an engine start request while driving the wheel by the motor, even if the motor speed is less than the engine speed at which the engine can be started, By applying the control pattern, the engine can be started reliably in a short time.

[0013] Another characteristic configuration of the hybrid vehicle drive device according to the present invention includes: a motor; a first clutch that transmits or disconnects a driving force between the motor and the engine; and the motor and the engine. A second clutch that transmits or disconnects one or both of the driving forces to the wheel side, and a control device that controls the operation of the motor, the first clutch, and the second clutch. When an engine start request is made while the wheel is driven by the motor, and the rotational speed of the motor is less than a predetermined threshold value, the engine is operated with the second clutch open. It is in the point of performing control to start

[0014] According to this characteristic configuration, when the engine speed is requested while the wheels are being driven by the motor and the motor rotation speed is less than the predetermined threshold value, the second clutch is opened. To start the engine. Therefore, when the engine starts, The engine can be reliably started while maintaining the smooth operation state of the wheel without transmitting the fluctuation of the rotational speed to the wheel side.

[0015] A further characteristic configuration of the hybrid vehicle drive device according to the present invention includes a motor, a first clutch that transmits or disconnects a driving force between the motor and the engine, the motor and the engine. A second clutch that transmits or disconnects one or both of the driving forces to the wheel side, and a control device that controls the operation of the motor, the first clutch, and the second clutch. When the engine is requested to start while the wheels are driven by the motor, if the rotational speed of the motor is less than a predetermined threshold value, the second clutch is released and the first clutch is disengaged. Engage and start the engine with the motor rotating speed higher than the engine starting speed, and after starting the engine, release the first clutch and engage the second clutch. That there is a point to carry out control.

[0016] According to this characteristic configuration, when there is an engine start request during driving of the wheels by the motor, the second clutch is released if the rotational speed of the motor is less than a predetermined threshold value. In this state, the first clutch is engaged and the engine is cranked and started by rotation of the motor. After the engine is started, the first clutch is released and the second clutch is engaged. Therefore, while maintaining the smooth operating state of the wheel, the fluctuation of the driving force when the first clutch is engaged and the fluctuation of the rotation speed of the motor at the start of the engine are not transmitted to the wheel side. The engine can be started.

[0017] Further, after the engine is started, at least when the second clutch is fully engaged, the control device drives the motor to rotate at a rotational speed corresponding to the rotational speed on the wheel side of the second clutch. It is preferable to perform control.

As such control, for example, when the second clutch is engaged after the engine is started, the control device synchronizes the rotation speed of the motor with the rotation speed of the wheel side of the second clutch, For example, when the control device is engaged with the second clutch after the engine is started, the control device can control the number of rotations of the motor. After synchronizing with the wheel speed Control for starting engagement of the second clutch can also be performed.

[0018] Thus, the second clutch is engaged in a state where the rotation speeds of the motor side and the wheel side of the second clutch are substantially the same. Therefore, when the second clutch is engaged, the difference in rotational speed between the two sides is absorbed to prevent fluctuations in the driving force from being transmitted to the wheel side. Thereby, the smooth operation state of a wheel can be maintained. Moreover, it can be set as the structure with few loads, such as friction which acts with respect to a 2nd clutch. Therefore, it is possible to extend the life of the second clutch, or it is possible to use an inexpensive clutch that hardly transmits the driving force while slipping as the second clutch. As a result, for example, it is possible to configure the second clutch using a clutch, a brake, or the like inside an automatic transmission that has been generally used conventionally.

[0019] Further, the control device performs rotational speed control on the motor when the second clutch is disengaged, and performs torque control on the motor when the second clutch is engaged. This is preferable.

[0020] As a result, in a state where the second clutch is released and the driving force of the motor is not transmitted to the wheel side, control is performed to maintain the motor rotation speed at or above the rotation speed necessary for engine start, and the engine start This ensures that the engine can be started regardless of the amount of torque required for this. Further, in a state where the second clutch is engaged and the driving force of the motor is transmitted to the wheel side, it is possible to run the vehicle by operating the motor to respond to the torque request based on the accelerator pedal operation by the driver. it can.

[0021] Here, it is preferable that the threshold value is set to be equal to or higher than a rotational speed at which the engine can be started.

[0022] This ensures that the engine can be started in a short time when the engine speed is less than the engine speed required when the engine is requested to drive the wheel while the motor is driving. It becomes possible to make it.

[0023] The characteristic configuration of the control method for a hybrid vehicle drive device according to the present invention includes a motor, a first clutch that transmits or disconnects a driving force between the motor and the engine, and the motor and the engine. The second that transmits or cuts one or both driving forces to the wheel side A method for controlling a hybrid vehicle drive device comprising a clutch, wherein when the engine is requested to start while the wheels are being driven by the motor, the rotational speed of the motor is a predetermined threshold value. If it is less, the second clutch is disengaged and the first clutch is engaged, and the engine is started with the rotational speed of the motor being equal to or higher than the rotational speed at which the engine can be started. After starting, the first clutch is disengaged and the second clutch is engaged.

[0024] According to this characteristic configuration, when there is a request for starting the engine while the wheel is driven by the motor, the second clutch is released if the rotational speed of the motor is less than a predetermined threshold value. In this state, the first clutch is engaged and the engine is cranked and started by the rotation of the motor. After the engine is started, the first clutch is released and the second clutch is engaged. Therefore, while maintaining the smooth operating state of the wheel without transmitting the fluctuation of the driving force when the first clutch is engaged and the fluctuation of the rotation speed of the motor when starting the engine to the wheel side, The engine can be started reliably.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a conceptual diagram showing an outline of a system configuration of a hybrid vehicle drive device according to the present embodiment.

The drive device 1 according to the present embodiment is a device that is mounted on a hybrid vehicle and that transmits the drive force of one or both of the motor generator MZG and the engine E to the wheels W. In addition, the driving device 1 starts the engine E by transmitting the driving force of the motor generator MZG to the engine E when the engine E is stopped. Therefore, this drive device 1 includes a motor 'generator MZG, a motor' generator MZG, a first clutch C1 that transmits or disconnects driving force between the engine E and a motor 'generator M / G and wheels W. A transmission 2 that is disposed between and functions as a second clutch C2 that transmits or disconnects the driving force of one or both of the motor generator MZG and the engine E to the wheel W side, and controls the operation thereof. It has a control device 3. The output shaft 4 of the transmission 2 is connected to the differential gear 5, and the driving force is transmitted to the wheels W via the drive shaft 6. Here, as engine E, gasoline engine or An internal combustion engine such as a diesel engine is preferably used.

[0027] As shown in FIG. 1, the system configuration of the drive unit 1 is as follows: engine E, first clutch Cl, motor generator M / G, and second clutch C2 along the drive force transmission path. It can be expressed as a configuration in which the transmission 2 that functions also, and the wheels W are connected in series in this order. In FIG. 1, in order to express the system configuration of the drive device 1 according to the present embodiment in an easy-to-understand manner, the inside of the transmission 2 is separated into a second clutch C2 and a transmission mechanism 7 and functionally represented. Yes.

The motor / generator M / G receives the supply of electric power from the battery 9 converted from direct current to alternating current by the inverter 8 and rotationally drives the intermediate shaft 10. The intermediate shaft 10 is connected at one end to a crankshaft 11 that rotates synchronously with a crankshaft (not shown) of the engine E via a first clutch C1, and has the other end connected to a shift of the transmission 2 via a second clutch C2. Connected to mechanism 7. Therefore, the motor generator M / G can start (crank) the engine E when the first clutch C1 is engaged, and drive the wheel W when the second clutch C2 is engaged. It has a configuration that can.

The motor / generator M / G can be operated as a generator when the intermediate shaft 10 is driven by the driving force from the engine E or the wheel side. In this case, the electric power generated by the motor generator MZG is converted from AC to DC by the inverter 8 and stored in the battery 9.

The operation control of the motor / generator MZG is performed based on a control signal from the MZG control device 12.

[0029] The first clutch C1 is arranged between the motor / generator M / G and the engine E, and is rotated by the motor / generator MZG 10, and the engine E is not shown in FIG. By connecting or disconnecting the crankshaft 11 that rotates synchronously with the shaft, the driving force is transmitted or disconnected between the engine E and the motor generator MZG.

Therefore, when the engine E is stopped, it is possible to start the engine E by transmitting the driving force of the motor generator MZG to the engine E by engaging the first clutch C1. Further, during the operation of the engine E, the driving force of the engine E is transmitted to the wheels W through the transmission 2 by engaging the first clutch C1. As such a first clutch CI, a clutch capable of transmitting a driving force while sliding in a half-engaged state until the engagement starting force is also in a fully engaged state is preferably used. For example, a wet multi-plate clutch or the like is used.

The operation control of the first clutch C1 is performed based on a control signal from the first clutch control device 13.

[0030] The transmission 2 here is disposed between the motor / generator MZG and the wheel W, and is rotated from the intermediate shaft 10 that is rotationally driven by the driving force of one or both of the motor / generator MZG and the engine E. The input rotation is shifted at a desired speed ratio and output to the output shaft 4, and the driving force (rotation) is transmitted to or disconnected from the output shaft 4.

As such a transmission 2, a stepped automatic transmission (AT automatic transmission) or a continuously variable transmission (CVT) is preferably used. In this embodiment, the transmission 2 is a stepped automatic transmission such as a six-speed transmission, for example. This is a planetary gear train for shifting the input rotation transmitted through the intermediate shaft 10 at a desired gear ratio and outputting it to the output shaft 4, and a clutch and brake for controlling the operation of this planetary gear train. have. Then, the transmission 2 switches to a desired gear stage by engaging or releasing these clutches and brakes, or the driving force input from the intermediate shaft 10 is applied to the output shaft 4. It can be in the idle state that is not transmitted.

That is, the transmission 2 selects a desired shift speed and switches between a transmission state in which the driving force input from the intermediate shaft 10 is transmitted to the output shaft 4 and an idling state in which the driving force is not transmitted to the output shaft 4. Can also function as the second clutch C2. Therefore, as described above, the transmission 2 can be considered as having only the second clutch C2 and the transmission mechanism 7 from a functional viewpoint.

In the present embodiment, the operation control of the transmission 2 is performed based on a control signal from the transmission control device 14.

[0031] The control device 3 includes an engine control device 15 that controls the operation of the engine E, an MZG control device 12 that controls the operation of the motor generator MZG, and a first clutch control device that controls the operation of the first clutch C1. 13. Transmission control device 14 for controlling operation of transmission 2, and vehicle A vehicle control device 16 that controls the operation of both is provided.

Further, the vehicle control device 16 includes a rotation speed sensor 17 for detecting the rotation speed of the intermediate shaft 10 (in this embodiment, the rotation speed Rmg of the motor / generator MZG), and the rotation of the output shaft 4 of the transmission 2. A detection signal from a vehicle speed sensor 18 that detects the number of pedals, an accelerator sensor 20 that detects the amount of depression of the accelerator pedal 19 (accelerator opening), and a brake sensor 22 that detects the amount of depression of the brake pedal 21 It has become.

Further, the memory 23 of the vehicle control device 16 stores a state flag determined by the vehicle control device 16 based on information from each part of the vehicle, as will be described later.

Next, operation control of the drive device 1 according to the present embodiment will be described based on the drawings.

2 to 5 are flowcharts showing the operation control of the drive device 1 according to the present embodiment. FIG. 6 and FIG. 7 are timing charts showing the operating state of each part when the engine is started in the driving apparatus 1 according to the present embodiment.

As shown in FIG. 2 to FIG. 7, in the present embodiment, the control device 3 is configured such that when there is a start request for the engine E while the wheel W is being driven only by the motor / generator MZG, 'Two types of control pattern for high rotation (control processing for engine start at high speed) and control pattern for low rotation (control processing for engine start at low speed) according to the rotation speed Rmg of generator MZG The engine E start control is performed according to the control pattern.

Hereinafter, the operation control of the drive device 1 according to the present embodiment will be described in detail with a focus on the operation control for starting the engine E.

[0034] FIG. 2 shows four driving motors 1, "motor running", "engine start at high speed", "engine start at low speed", and "engine + motor 'generator running". 5 is a flowchart showing a flow of processing in the control device 3 when selecting one of the control processing. As shown in this figure, when the status flag stored in the memory 23 is in the state of “EV” indicating “motor running” (step # 01: YES), the control device 3 Select and execute control processing (Step # 02). Control device 3 is in the state of “EstartH” indicating that the state flag is “high speed engine start” (step # 03: YE S), select and execute the control process of “engine start at high speed” (step # 04). When the status flag is in the state of “EstartL” indicating “low speed engine start” (step # 05: YES), the control device 3 selects and executes the “low speed engine start” control process. (Step # 06). When the status flag is “E + M / GJ” (step # 07: YES), the control device 3 performs the control process for “engine + motor / generator running”. Select and run (Step # 08).

Here, the state flag is determined in the vehicle control device 16 based on information from various parts of the vehicle including the accelerator sensor 20, the brake sensor 22, the vehicle speed sensor 18, and the rotation speed sensor 17, and is stored in the memory. Stored in 23. This state flag can be determined by comparing information from each part of the vehicle with a running state map using this information as a parameter.

FIG. 3 is a flowchart showing details of the control process of step # 02 “motor running” in the flowchart of FIG. As shown in this figure, in the “motor running” control process, until the engine start request is made (step # 11: NO), the status flag stored in the memory 23 is “EV running” indicating “motor running”. "(Step # 12). Here, the engine start request is issued when the accelerator opening becomes large and the output torque is insufficient with the motor 'generator MZG alone, or when the remaining amount of the battery 9 for driving the motor' generator MZG is low. The vehicle control device 16 outputs the engine control device 15, the MZG control device 12, the first clutch control device 13, and the transmission control device 14.

[0037] Then, the control device 3 sets the operating pressure P1 of the first clutch C1 to zero (step # 13), and the operating pressure P2 of the second clutch C2 The resultant pressure is P2 e (Step # 14). The control device 3 operates the motor / generator MZG so that the output torque Tmg of the motor / generator M / G matches the required torque Tth (step # 15).

Here, the required torque Tth is determined by the vehicle control device 16 based on the accelerator opening information detected by the accelerator sensor 20. At this time, it is desirable to prevent the output torque for the accelerator opening from being different between when traveling by the engine and when traveling by the motor generator MZG. Therefore, the accelerator opening and the motor generator M The relationship between the ZG output torque Tmg and the relationship between the accelerator opening and the engine output torque is suitable. Therefore, here, the required torque Tth is determined in accordance with the accelerator opening detected by the accelerator sensor 20 so as to coincide with the engine output torque at the accelerator opening at that time. As a result, it is possible to perform motor traveling reflecting the output request by the driver's accelerator operation without causing the driver to feel uncomfortable even during motor traveling.

[0038] Then, when there is a request for starting the engine (step # 11: YES), the control device 3 determines whether the rotational speed Rmg of the motor / generator MZG is threshold! /, And whether it is less than the value rotational speed Rt. Determine (Step # 16). In the present embodiment, the rotational speed Rmg of the motor generator MZG is detected based on a detection signal from the rotational speed sensor 17 that detects the rotational speed of the intermediate shaft 10.

The threshold rotational speed Rt is set to a rotational speed equal to or higher than the rotational speed of the motor / generator MZG that can start the engine E when the first clutch C1 is fully engaged. That is, the threshold rotational speed Rt is equal to or higher than the rotational speed at which the engine E can be started when the first clutch C1 is fully engaged and the engine E cranking rotational speed is driven by the driving force of the motor generator MZG. Is set to be Specifically, it is desirable to set it to about the idling speed of engine E, for example, about 600 to 700 rpm is preferable.

[0039] When the rotational speed Rmg of the motor generator MZG is not less than the threshold rotational speed Rt (step # 16: NO), the control device 3 sets the status flag stored in the memory 23 to "high rotational speed". “EstartH” indicating “hour engine start” (step # 17). As a result, as shown in the flow chart of FIG. 2, control of “engine start at high speed” (step # 04) is performed. On the other hand, if the rotation speed Rmg of the motor / generator M / G is less than the threshold rotation speed Rt (step # 16: YES), the status flag stored in the memory 23 is set to “Start engine at low speed”. "EstartL" (step # 18). As a result, as shown in the flowchart of FIG. 2, the control of “engine start at low speed” (step # 06) is performed. This completes the control process for “motor running”.

[0040] FIG. 4 shows the control of step # 04 “start engine at high speed” in the flowchart of FIG. It is a flowchart which shows the detail of a control process. As shown in this figure, in the control process of “engine start at high speed”, first, the control device 3 determines whether or not the operating pressure P1 of the first clutch C1 is the standby pressure Pis ( Step # 31). If the operating pressure P1 of the first clutch C1 is not the standby pressure Pis (step # 31: NO), the operating pressure P1 of the first clutch C1 is set to the stunning pressure Pis (step # 32). Here, the standby pressure Pis of the first clutch C1 is a pressure for bringing the first clutch C1 into a ready state before the start of engagement, and is a pressure for operating the first clutch C1 to a state immediately before the start of engagement. It is preferable to set.

Then, with the working pressure P2 of the second clutch C2 set to the full engagement pressure P2e (step # 33), the motor generator MZG is operated so that the output torque Tmg of the motor generator MZG matches the required torque Tth. (Step # 34).

[0041] When the operating pressure P1 of the first clutch C1 becomes the standby pressure Pis (step # 31: YES), the control device 3 determines whether or not the engine E is in a complete explosion state. (Step # 35). Whether or not the engine has completely exploded is determined based on detection signals input to the engine control device 15 from various sensors provided in the engine.

[0042] When engine E is not in the complete explosion state (step # 35: NO), control device 3 keeps operating pressure P2 of second clutch C2 at full engagement pressure P2e (step # 36). ), The operating pressure P1 of the first clutch C1 is increased at a predetermined rate of change to the full engagement pressure Pie at which the first clutch C1 is fully engaged (step # 37). Thus, the engagement pressure of the first clutch C1 can be increased. In the present embodiment, the control for increasing the operating pressure P1 of the first clutch C1 to the full engagement pressure Pie is performed by detecting the slip amount of the first clutch C1 and until the slip amount becomes zero. Feedback control is used to increase the operating pressure P1.

[0043] Then, clutch transmission torque Tc transmitted from motor generator M / G to engine E via first clutch C1 is detected (step # 38). This clutch transmission torque Tc force Corresponds to the torque used to crank and start engine E by motor generator M / G via first clutch C1.

The detection of the clutch transmission torque Tc is based on, for example, the operating pressure P1 of the first clutch C1. The vehicle control device 16 can calculate the clutch transmission torque Tc. That is, at this time, the first clutch C1 is controlled to increase its operating pressure P1 to the full engagement pressure Pie (step # 37). Therefore, the greater the torque transmitted in the first clutch C1, the greater the engagement with the larger operating pressure P1 (complete engagement pressure Pie). Therefore, the operating pressure P1 of the first clutch C1 has a certain relationship with the clutch transmission torque Tc transmitted by the first clutch C1. Therefore, the vehicle control device 16 uses the relational expression or table between the operating pressure P1 of the first clutch C1 and the clutch transmission torque Tc, based on the operating pressure P1 of the first clutch C1. Clutch transmission torque Tc can be calculated.

[0044] Then, control device 3 operates motor generator MZG so as to obtain a torque obtained by adding clutch transmission torque Tc to output torque Tmg force required torque Tth of motor / generator MZG (step # 39). As a result, the engine E can be started while the motor travels reflecting the output request by the driver's accelerator operation. The required torque Tth is determined by the vehicle control device 16 based on the accelerator opening information detected by the accelerator sensor 20 as described above.

[0045] When the engine E reaches the complete explosion state (step # 35: YES), the control device 3 sets the state flag stored in the memory 23 to "engine + motor 'generator running". “E + MZG” shown (step # 40). As a result, as shown in the flowchart of FIG. 2, the “engine + motor / generator running” control (step # 08) is performed. This completes the control process for “starting the engine at high speed”.

[0046] FIG. 6 is an example of a timing chart showing the operation state of each part when engine E is started according to the control process of "high speed engine start" after "motor running" is performed from the stop state of the vehicle. It is. In the example shown in this figure, when the brake pedal is depressed by the driver, the vehicle is stopped (area A). Next, when the brake pedal is released by the driver, the control device 3 starts to rotate the motor 'generator MZG accordingly, as in the creep state in an automatic' transmission vehicle equipped with a torque converter. Output a torque that slowly moves forward (region B). This starts “motor running”. Then, the accelerator pedal 19 is depressed by the driver. Then, the control device 3 operates the motor / generator MZG so that the output torque Tmg of the motor / generator MZG matches the required torque Tth (see step # 15 in FIG. 3), and “motor running” is performed. (Area C).

[0047] Then, when an engine start request is output from the vehicle control device 16, the control device 3 starts control of "engine start at high speed". That is, the operating pressure P1 of the first clutch C1 is set to the standby pressure Pis (see step # 32 in FIG. 4), and the first clutch C1 is operated to a state just before the engagement is started (region D). Then, while increasing the operating pressure P1 of the first clutch C1 to the full engagement pressure Pie at a predetermined rate of change (see step # 37 in Fig. 4), the output torque Tmg of the motor generator MZG becomes the required torque Tth. The motor / generator MZG is operated so that the clutch transmission torque Tc is added (see step # 39 in Fig. 4), and the engine E is started (region E). The example shown in FIG. 6 shows a case where the engine start request is output because the remaining amount of the notch 9 is less than the increase in the accelerator opening.

[0048] After engine E has completely exploded and started, "engine + motor 'generator running" is started. At this time, while maintaining the required torque Tth, the engine E output torque Te is increased while the output torque Tmg of the motor generator M ZG is decreased, and the ratio of the engine E output torque Te is continuously increased. Boost your power! ] (Area F). In the steady state of “engine + motor 'generator running”, the output torque Te of engine E is equal to the torque obtained by adding the required torque Tth and the torque required for power generation by motor / generator MZG (power generation torque) Teg. . In this state, the vehicle is driven by the output torque Te of the engine E, and the motor generator MZG is driven to rotate and operates as a generator (region G).

During the series of operations shown in FIG. 6, the operating pressure P2 of the second clutch C2 remains at the full engagement pressure P2e. Further, when performing the control process of “engine start at high rotation”, the motor generator MZG is controlled by torque control in all the above regions B to G.

FIG. 5 is a flowchart showing details of the control process of step # 06 “engine start at low speed” in the flowchart of FIG. As shown in this figure, the engine at low speed In the “start” control process, first, the control device 3 determines whether or not the operating pressure P1 of the first clutch C1 is the standby pressure Pis and the operating pressure P2 of the second clutch C2 is the standby pressure P2s. (Step # 51). If not (step # 51: NO), the operating pressure PI of the first clutch C1 is set to the standby pressure Pis (step # 52). Here, the standby pressure Pis of the first clutch C1 is a pressure for setting the first clutch C1 in a preparation state before the start of engagement, and is a pressure for operating the first clutch C1 to a state immediately before the start of engagement. It is preferable to set.

Then, the operating pressure P2 of the second clutch C2 is set to the standby pressure P2s (step # 53). Here, the standby pressure P2s of the second clutch C2 is a pressure that brings the second clutch C2 into an open state, and is an arbitrary pressure between the pressure that makes the second clutch C2 in a state immediately before the start of engagement and the pressure zero. It can be a pressure.

[0050] Then, control device 3 performs the rotational speed control so as to maintain the rotational speed Rmg of motor'generator MZG at the engine start rotational speed Res (step # 54). This engine start rotational speed Res is equal to or higher than the rotational speed of the motor generator MZG that can start the engine E when the first clutch C1 is in the fully engaged state, like the threshold rotational speed Rt. Set to the number of rotations. Specifically, it is desirable to set the engine E to about the idling speed, for example, about 600 to 700 rpm.

Note that the rotation speed control for maintaining the motor / generator MZG at the predetermined rotation speed in this way is performed so that the motor / generator MZG has the predetermined rotation speed regardless of the load acting on the intermediate shaft 10. This can be done by controlling the output torque Tmg.

[0051] When the operating pressure P1 of the first clutch C1 is the standby pressure Pis and the operating pressure P2 of the second clutch C2 is the standby pressure P2s (step # 51: YES), the control device 3 Judgment is made as to whether or not engine E is in a complete explosion (step # 55). Whether or not the engine is completely detonated is determined based on detection signals input to the engine control unit 15 for various sensor forces provided in the engine.

[0052] When the engine E is not in the complete explosion state (step # 55: NO), the control device 3 keeps the operating pressure P2 of the second clutch C2 at the standby pressure P2s (step # 56). first The operating pressure PI of the clutch CI is increased at a predetermined rate of change until the fully engaged pressure Pie at which the first clutch CI is fully engaged (step # 57). During this time, the rotational speed control is performed so that the rotational speed Rmg of the motor / generator MZG is maintained at the engine start rotational speed Res (step # 58).

At this time, by raising the operating pressure P1 of the first clutch C1 to the full engagement pressure P1e, the first clutch C1 enters the fully engaged state through the half-engaged state. As a result, the intermediate shaft 10 that is driven to rotate by the motor generator MZG is connected to the crankshaft 11 that rotates in synchronization with a clutch shaft (not shown) of the engine E, and the crankshaft of the engine E is driven by the driving force of the motor generator MZG. Will be rotated. Therefore, to maintain the motor generator MZG speed Rmg at the engine start speed Res, the output torque Tmg of the motor 'generator MZG must be increased by the torque required for engine E cranking. (Refer to area K in Fig. 7).

As a result, the second clutch C2 is disengaged so that the motor 'generator MZG's driving force is not transmitted to the output shaft 4, and the change in the rotational speed Rmg of the motor' generator MZG does not affect the running state of the vehicle. In this state (idle running state), the engine E can be started by increasing the speed Rmg of the motor / generator MZG to a speed at which the engine E can be started. Therefore, even if the rotation speed Rmg of the motor / generator MZG during “motor running” is low, the fluctuation of the rotation speed Rmg of the motor / generator MZG at the start of the engine E is transmitted to the wheel W. The engine E can be reliably started while maintaining the smooth operating state of the wheel W without any trouble.

When engine E reaches the complete explosion state (step # 55: YES), control device 3 determines the number of revolutions of motor / generator M / G, Rmg force, number of revolutions of wheel W of second clutch C2, and W side. The number of revolutions according to the following (hereinafter referred to as “second clutch wheel side revolutions”) is determined by whether or not it is Rw (step # 59).

Here, the second clutch wheel side rotation speed Rw is determined when the second clutch C2 is fully engaged, and the motor / generator MZG side (intermediate shaft 10 side) and the wheel W side (transmission mechanism) of the second clutch C2. This is the rotation speed of the motor / generator M / G when the rotation speed is almost the same with the difference within the specified range. That is, this second clutch wheel side rotation speed Rw is Depending on the running speed of the vehicle and the speed selected in the speed change mechanism 7, the number of revolutions varies. Here, the traveling speed of the vehicle can be detected by the vehicle speed sensor 18. The gear stage of the transmission mechanism 7 is controlled by the transmission control device 14.

In this determination of step # 59, the second clutch wheel side rotational speed Rw is set to a value having a certain range, and the rotational speed Rmg of the motor generator MZG is within the corresponding range of the second clutch wheel side rotational speed Rw. If it is within the range, it is preferable to judge that the condition is satisfied.

[0054] In the case where the rotation speed Rmg of the motor / generator M / G is V which is the rotation speed Rw on the second clutch wheel side (step # 59: NO), the operating pressure P2 of the second clutch C2 is set to the standby pressure P2s. (Step # 60), the operating pressure P1 of the first clutch C1 is set to the standby pressure P1 s (step # 61). Then, the rotational speed control is performed so that the rotational speed Rmg of the motor / generator M / G is synchronized with the rotational speed Rw of the second clutch wheel (step # 62).

The rotational speed control in which the rotational speed Rmg of the motor / generator M / G is set to the second clutch wheel-side rotational speed Rw is based on the vehicle running speed detected by the vehicle speed sensor 18 and the speed stage selected in the speed change mechanism 7. This can be done based on the second clutch wheel speed Rw determined from the information. That is, the output torque Tmg of the motor / generator MZG necessary for setting the rotation speed Rmg of the motor / generator M / G to the rotation speed Rw of the second clutch wheel is calculated, and the motor / generator MZG is calculated according to the calculation result. Control.

In this way, by synchronizing the rotation speeds of the motor's generator M / G side and wheel W side of the second clutch C2, when the second clutch C2 is engaged, the motor 'generator MZG side and wheels Absorbing the difference in rotational speed from the W side can prevent fluctuations in the driving force from being transmitted to the wheel side. Therefore, it is possible to prevent a large load from being applied to the second clutch C2 when the second clutch C2 is engaged, and to maintain a smooth operation state of the wheels.

[0055] Then, when the rotational speed Rmg force of the motor / generator M / G reaches the second clutch wheel side rotational speed Rw (step # 59: YES), the working pressure P2 of the second clutch C2 is completely engaged. Judgment is made as to whether or not the pressure is P2e (step # 63). This is the second This is a determination as to whether or not the clutch C2 is fully engaged. If the operating pressure P2 of the second clutch C2 becomes the full engagement pressure P2e (step # 63: NO), the operating pressure P1 of the first clutch C1 remains at the standby pressure Pis (step # 63). # 64), the working pressure P2 of the second clutch C2 is set to the full engagement pressure P2e (step # 65). During this time, the rotational speed control is performed so that the rotational speed Rmg of the motor generator MZG is maintained at the second clutch wheel-side rotational speed Rw (step # 66).

As a result, the wheel W can be driven by the driving force of the motor generator MZG while maintaining the smooth operation state of the wheel.

[0056] When the operating pressure P2 of the second clutch C2 becomes the complete engagement pressure P2e (step

# 63: YES), the control device 3 sets the status flag stored in the memory 23 to “E + M / G” indicating “engine + motor′generator running” (step # 67). As a result, as shown in the flowchart of FIG. 2, “engine + motor / generator running” control (step # 08) is performed.

This completes the control process for “starting the engine at low speed”.

[0057] FIG. 7 is an example of a timing chart showing the operation state of each part when the engine E is started according to the control process of "low speed engine start" after "motor running" is performed from the stop state of the vehicle. It is. In the example shown in this figure, the vehicle is in a stopped state (region H) when the brake pedal is depressed by the driver. Next, when the brake pedal is released by the driver, the control device 3 starts to rotate the motor generator MZG accordingly, and the vehicle is moved in the same way as in a creep state in an automatic transmission vehicle equipped with a torque converter. Output torque that slowly moves forward (area 1). As a result, “motor running” is performed.

[0058] Then, when the accelerator pedal 19 is depressed by the driver, the control device 3 starts the control of "engine start at low speed". In the example shown in FIG. 7, the accelerator pedal 19 is largely depressed from the state where the accelerator pedal 19 is not depressed and the vehicle is moving forward slowly. Therefore, the motor 'generator M / G alone has insufficient output torque, and the engine is started with the motor's generator MZG speed Rmg being a low speed less than the threshold speed Rt. It is. I.e. The operating pressure P 1 of the clutch C 1 is set to the standby pressure P 1 s (see step # 52 in FIG. 5), and the operating pressure P2 of the second clutch C2 is set to the standby pressure P2s (see step # 53 in FIG. 5). Set the motor 'generator MZG's driving force to the output shaft 4 in the idling state (idle state). At this time, the control device 3 starts the rotational speed control for maintaining the rotational speed Rmg of the motor “generator MZG at the engine start rotational speed Res (see step # 54 in FIG. 5).

[0059] After that, the control device 3 performs the rotational speed control to maintain the rotational speed Rmg of the motor'generator MZG at the engine start rotational speed Res (see step # 58 in FIG. 5), while the first clutch C1 The operating pressure P1 is increased at a predetermined rate of change to the fully engaged pressure Pie at which the first clutch C1 is fully engaged (see step # 57 in FIG. 5), and the engine E is started (region K). At this time, the output torque Tmg of the motor / generator M / G increases by the amount of torque required for engine E clamping.

[0060] After the engine E has completely exploded and started, the control device 3 keeps the operating pressure P2 of the second clutch C2 at the standby pressure P2s (see step # 60 in FIG. 5), and the first clutch C1 Is set to the standby pressure Pis (see step # 61 in Fig. 5). Then, the rotational speed Rmg of the motor / generator M / G is synchronized with the rotational speed Rw of the second clutch wheel (see step # 62 in FIG. 5) (region L).

Then, the operating pressure P 1 of the first clutch C 1 is set to the standby pressure P 1 s (see step # 64 in FIG. 5), and the rotation speed Rmg of the motor / generator M / G is set to the rotation speed Rw of the second clutch wheel. While maintaining (see step # 66 in FIG. 5), the operating pressure P2 of the second clutch C2 is set to the full engagement pressure P2e (see step # 65 in FIG. 5). As a result, the wheel W is driven by the driving force of the motor / generator M / G (region M).

In the timing chart shown in FIG. 7, the operating pressure P2 of the second clutch C2 is set at a predetermined change rate while synchronizing the rotational speed Rmg of the motor / generator MZG with the second clutch wheel-side rotational speed Rw. Control to raise. This is to shorten the time required for engaging the second clutch C2.

As described with reference to the flowchart of FIG. 5, after synchronizing the rotational speed Rmg of the motor generator MZG with the second clutch wheel side rotational speed Rw, the second clutch C2 It is also possible to adopt a configuration that starts to increase the operating pressure P2. In this case, the time required for engagement of the second clutch C2 can be shortened by synchronizing the rotation speed Rmg of the motor generator MZG with the second clutch wheel side rotation speed Rw in a short time.

[0062] Thereafter, "engine + motor 'generator running" is started. Specifically, the output torque Tmg of the motor / generator MZG is decreased to increase the output torque Te of the engine E, and the operating pressure P1 of the first clutch C1 is increased to the full engagement pressure Pie at a predetermined change rate. (Region N). At this time, while the operating pressure P1 of the first clutch C1 is increased from the standby pressure Pis to the full engagement pressure Pie, the output torque Te of the engine E is increased and the first clutch C1 is slid in a half-engaged state. The engine E output torque Te is transmitted. As a result, the fluctuation of the output torque Te transmitted to the wheel W side is moderated.

In the steady state of "engine + motor 'generator running", the output torque Te of engine E is equal to the torque obtained by adding the required torque Tth and the torque required for power generation by the motor generator MZG (power generation torque) Teg. . In this state, the vehicle is driven by the output torque Te of the engine E, and the motor / generator MZG is driven to rotate and operates as a generator (region 0).

As described above, when performing the control process of “engine start at low speed”, the control device 3 rotates with respect to the motor generator M / G in the region where the second clutch C2 is in an open state to M. Perform number control. On the other hand, the control device 3 performs torque control on the motor / generator MZG in the regions H, I, N and O in which the second clutch C2 is completely engaged.

[0063] [Another embodiment]

(1) In the above embodiment, the configuration for detecting the rotational speed Rmg of the motor generator MZG based on the detection signal from the rotational speed sensor 17 that detects the rotational speed of the intermediate shaft 10 has been described. However, the means for detecting the rotational speed Rmg of the motor / generator M / G is not limited to this, and any means capable of detecting the rotational speed Rmg of the motor / generator MZG directly or indirectly may be used. Therefore, for example, based on the detection signal from the vehicle speed sensor 18 that detects the rotation speed of the output shaft 4 of the transmission 2 and the information on the V and the gear stage selected in the transmission 2! /, Indirectly Motor / generator MZG speed Rm A configuration for detecting g is also one preferred embodiment.

[0064] (2) In the above embodiment, when there is a request to start the engine E while the wheel W is driven only by the motor 'generator MZG, the high-rotation control pattern is determined according to the rotational speed Rmg of the motor' generator MZG. We explained the case where engine E start control is performed using two control patterns: a low-speed control pattern and a low-speed control pattern. However, it is of course possible to perform start control of engine E with three or more control patterns according to the rotational speed Rmg of the motor generator MZG.

[0065] (3) In the above embodiment, as the control process for the K region in FIG. 7, while the operating pressure of the first clutch is increased at a predetermined rate of change, the rotational speed Rmg of the motor / generator MZG is engine-started. The case of performing the rotation speed control maintained at the rotation speed Res has been described. However, it is also possible to control the engagement of the first clutch by rapidly increasing the operating pressure. In this case, the load acting on the engine E increases, but the time required to start the engine E can be shortened.

[0066] (4) In the above embodiment, the case where the standby pressure Pis of the first clutch C1 is set to a pressure at which the first clutch C1 is operated to the state immediately before the start of engagement has been described as an example. However, the Stanno pressure Pis is not limited to this, and can be any pressure between the pressure immediately before the engagement of the first clutch C1 and the pressure zero.

Industrial applicability

The present invention can be suitably used for a hybrid vehicle that travels using both an engine and a motor.

Brief Description of Drawings

FIG. 1 is a conceptual diagram showing an outline of a system configuration of a hybrid vehicle drive device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a flow of control processing selection in the hybrid vehicle drive device according to the embodiment of the present invention.

FIG. 3 is a flowchart showing details of the control process of step # 02 “motor running” in the flowchart of FIG. [Fig.4] Flowchart showing the details of the control process of Step # 04 “Engine start at high speed” in the flowchart of Fig.2

FIG. 5 is a flowchart showing the details of the control process of Step # 06 “Engine Start at Low Rotation” in the flowchart of FIG.

FIG. 6 is an example of a timing chart showing an operation state of each part when the engine is started in accordance with the control process of “high speed engine start” in the hybrid vehicle drive device according to the embodiment of the present invention.

FIG. 7 is an example of a timing chart showing the operation state of each part when starting the engine E according to the control process of “engine start at low speed” in the hybrid vehicle drive device according to the embodiment of the present invention.

Explanation of symbols

1 Drive unit

2 Transmission

3 Control unit

4 Output shaft

E engine

M / G motor 'generator

W wheel

C1 first clutch

C2 Second clutch

Rmg motor 'generator speed

Rt threshold speed

Rw Second clutch wheel side rotation speed

Claims

The scope of the claims

[1] A motor, a first clutch that transmits or disconnects driving force between the motor and the engine, and a first clutch that transmits or disconnects driving force of one or both of the motor and the engine to the wheel side. A drive device for a hybrid vehicle, comprising: two clutches; and a control device that controls operation of the motor, the first clutch, and the second clutch,

When an engine start request is made while the wheels are being driven by the motor, the control device is configured to control the motor and the first according to a control pattern that differs depending on the rotation speed of the motor detected directly or indirectly. Controls the operation of the clutch and the second clutch.

V, a hybrid vehicle drive device for starting the engine.

[2] The control device has at least two control patterns of a high rotation control pattern and a low rotation control pattern as the control pattern,

The control pattern for high rotation is a control pattern for starting the engine by increasing the engagement pressure of the first clutch with the second clutch fully engaged, and the control pattern for low rotation is the control pattern for the low rotation 2. The hybrid vehicle drive device according to claim 1, wherein the hybrid vehicle drive system is a control pattern for starting the engine by increasing the engagement pressure of the first clutch with the second clutch opened.

[3] The control device uses the high rotation speed when the rotation speed of the motor is equal to or higher than a threshold value set to be equal to or higher than the rotation speed at which the engine can be started with the first clutch engaged. 3. The hybrid vehicle drive device according to claim 2, wherein a control pattern is selected, and control is performed to select the low-rotation control pattern when the threshold is less than the threshold value.

[4] A motor, a first clutch that transmits or disconnects driving force between the motor and the engine, and a first clutch that transmits or disconnects driving force of one or both of the motor and engine to the wheel side. A drive device for a hybrid vehicle, comprising: two clutches; and a control device that controls operation of the motor, the first clutch, and the second clutch,

When the engine is requested to start the wheel while the wheel is driven by the motor, the control device opens the second clutch if the rotational speed of the motor is less than a predetermined threshold value. Drive device for hybrid vehicle performing control for starting the engine

[5] A motor, a first clutch that transmits or disconnects driving force between the motor and the engine, and a first clutch that transmits or disconnects driving force of one or both of the motor and engine to the wheel side. A drive device for a hybrid vehicle, comprising: two clutches; and a control device that controls operation of the motor, the first clutch, and the second clutch,

The controller opens the second clutch when an engine start request is made while the wheels are being driven by the motor, and the rotational speed of the motor is less than a predetermined threshold value. The first clutch is engaged, the engine is started with the rotational speed of the motor being equal to or higher than the rotational speed at which the engine can be started, and after the engine is started, the first clutch is released and the second clutch is released. A hybrid vehicle drive system that controls clutch engagement.

[6] The control device performs control to drive the motor at a rotational speed corresponding to the rotational speed on the wheel side of the second clutch at least when the second clutch is completely engaged after the engine is started. The hybrid vehicle drive device according to claim 5, wherein the hybrid vehicle drive device is performed.

[7] When the second clutch is engaged after the engine is started, the control device synchronizes the rotational speed of the motor with the rotational speed of the wheel side of the second clutch, 6. The hybrid vehicle drive device according to claim 5, wherein control for increasing the engagement pressure is performed.

[8] When the second clutch is engaged after the engine is started, the control device synchronizes the rotational speed of the motor with the rotational speed of the second clutch on the wheel side, and then the second clutch. 6. The drive device for a hybrid vehicle according to claim 5, wherein control for starting engagement is performed.

[9] The control device performs control of the rotational speed for the motor when the second clutch is disengaged, and performs torque control for the motor when the second clutch is engaged. The drive device for a hybrid vehicle according to any one of 4 to 8.

10. The hybrid vehicle drive device according to any one of claims 4 to 8, wherein the threshold value is set to be equal to or higher than a rotational speed at which the engine can be started.

[11] A motor, a first clutch that transmits or disconnects driving force between the motor and the engine, and a first clutch that transmits or disconnects driving force of one or both of the motor and engine to the wheel side. A control method for a hybrid vehicle drive device comprising two clutches, When there is an engine start request during driving of the wheel by the motor, if the motor speed is less than a predetermined threshold value, the second clutch is opened and the first clutch A hybrid in which the motor is started with the motor rotating speed equal to or higher than the engine starting speed, the first clutch is released after the engine is started, and the second clutch is engaged. A method for controlling a vehicle drive device.