JP4910992B2 - Control device for hybrid vehicle - Google Patents

Description

  The present invention relates to a control device suitable for a hybrid vehicle.

  In addition to the internal combustion engine, a hybrid vehicle including a power source such as an electric motor or a motor generator is known. In a hybrid vehicle, an internal combustion engine is operated in a highly efficient state as much as possible, while excess or deficiency of driving force or engine brake is compensated by an electric motor or a motor generator.

  For example, Patent Literature 1 below includes a ring gear in a first planetary gear mechanism in which an engine and a first motor generator are connected, and a ring gear in a second planetary gear mechanism in which a second motor generator is connected. A hybrid vehicle having a mechanism that is connected and fixed with a carrier in a second planetary gear mechanism is described. Patent Document 2 describes a technique for preventing vibration in an electric vehicle by generating a driving force in the reverse rotation direction of the motor when the parking lock is released. Furthermore, techniques related to the present invention are also described in Patent Documents 3 and 4.

JP 2002-274201 A JP 2003-264908 A JP 2007-153110 A JP 2007-55460 A

  However, in the hybrid vehicle having the mechanism described in Patent Document 1, when the parking lock is released, an impact torque may be generated and an excessive load may be applied to the second motor generator. Further, with the technique described in Patent Document 2, it is not possible to prevent the impact torque generated when the parking lock is released.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a control device for a hybrid vehicle that can reduce the impact torque generated when the parking lock is released.

  In one aspect of the present invention, the first and second motor generators, the power distribution mechanism connected to the first and second motor generators, the drive wheels connected to the power distribution mechanism, the first A control device for a hybrid vehicle having a torque limiter connected between the motor generator and the internal combustion engine, a determination means for determining whether or not an impact torque is generated when the parking lock is released; In the locked state, when the determination means determines that an impact torque is generated when the parking lock is released, torque is applied to the second motor generator in a direction opposite to the direction of rotation when the parking lock is released. By outputting, the backlash of the drive system connected to the second motor generator is reduced. Control means for opening the drive system connected to the first motor generator by causing the first motor generator to output a torque in the same direction as the rotation direction when the parking lock is released. Prepare.

  The hybrid vehicle control apparatus includes: a first motor generator; a second motor generator; a power distribution mechanism connected to the first motor generator; a drive wheel connected to the power distribution mechanism; The present invention is applied to a hybrid vehicle having a torque limiter connected between a first motor generator and an internal combustion engine. The control device for a hybrid vehicle includes a determination unit and a control unit. These means are realized by, for example, an ECU (Electronic Control Unit). The determination means determines whether or not a mode in which an impact torque is generated when the parking lock is released is determined. When the determination means determines that the impact torque is generated when the parking lock is released in the parking lock state, the control means determines the direction of rotation when the parking lock is released with respect to the second motor generator. By outputting torque in the reverse direction, the drive system connected to the second motor generator is loosened and torque is applied to the first motor generator in the same direction as the rotation direction when the parking lock is released. Is output, the drive system connected to the first motor generator is loosened. By doing so, the impact torque can be reduced.

  Another aspect of the hybrid vehicle control device includes a parking control means for releasing the parking lock when receiving a parking release command from the driver, and the control means generates an impact torque when the parking lock is released. When the mode is determined by the determination means, the parking control means outputs the torque to the second motor generator after receiving the parking release command and before releasing the parking lock. The loosening is performed, and the loosening is performed by causing the first motor generator to output torque. By doing so, it is possible to shorten the time for the first and second motor generators to output torque for backlashing and backlashing, and to minimize loss.

  First and second motor generators, a power distribution mechanism connected to the first and second motor generators, drive wheels connected to the power distribution mechanism, the first motor generator and an internal combustion engine A control device for a hybrid vehicle having a torque limiter connected between the determination means for determining whether or not to enter a mode in which an impact torque is generated when the parking lock is released, and when the parking lock is released in the parking lock state. If it is determined by the determining means that the mode is to generate an impact torque, the second motor generator is caused to output torque in a direction opposite to the direction of rotation when the parking lock is released, thereby causing the second motor generator to output the second torque. The backlash of the drive system connected to the motor generator of the first motor generator is reduced. Regulator to comprise by outputting a torque in the same direction as the direction of rotation during parking lock, a control means for opening play of the first of the connected drive system to the motor generator, the. By doing so, the impact torque can be reduced.

  Preferred embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows a schematic configuration of a drive mechanism of a hybrid vehicle according to the present embodiment. The example of FIG. 1 is a hybrid device called a mechanical distribution type two-motor type. , ECU (Electronic Control Unit) 10. In FIG. 1, the solid line between the components indicates that the components are connected, and the broken arrow indicates the flow of the control signal and the detection signal. In FIG. 1, an engine 1 corresponding to a power source and a first motor generator MG1 corresponding to a rotation speed control mechanism are connected to a power distribution mechanism 20. The speed reducer 24 is connected to a second motor generator MG2 which is a sub power source for assisting driving torque or braking force. The output shaft 3 is, for example, a drive shaft, and the second motor generator MG2 and the output shaft 3 are connected via a speed reducer 24. Further, the output shaft 3 is connected to the left and right drive wheels 9 via a final reduction gear 8. Brakes 5 are attached to the left and right drive wheels 9. The first motor generator MG1 and the second motor generator MG2 are electrically connected via a battery, an inverter, or an appropriate controller (not shown) or directly, and the first motor generator MG1 The second motor generator MG2 is driven by the generated electric power.

  The engine 1 is a heat engine that generates power by burning fuel, and examples thereof include a gasoline engine and a diesel engine. The first motor generator MG1 generates power mainly by receiving torque from the engine 1 and rotating, and reaction force torque accompanying power generation acts. By controlling the rotational speed of first motor generator MG1, the rotational speed of engine 1 changes continuously.

  The second motor generator MG2 is a device that assists the driving torque or the braking force. When assisting the drive torque, the second motor generator MG2 receives power supply and functions as an electric motor. On the other hand, when assisting the braking force, the second motor generator MG2 functions as a generator that is rotated by the torque transmitted from the drive wheels 9 to generate electric power.

  The output shaft 3 is provided with a parking lock mechanism 4. The parking lock mechanism 4 includes a parking gear 4a attached to the output shaft 3, and a parking lock pole 4b that engages with the parking gear 4a and locks in a state where its rotational drive is stopped. The parking lock mechanism 4 is connected to the shift lever 31 by the cable 8 and is configured to be driven in conjunction with the shift lever 31. Specifically, when the shift lever 31 is set to the parking range, the parking lock pole 4b engages with the parking gear 4a to enter the parking lock state, and when the shift lever 31 is released from the parking range, the parking lock pole 4b is disengaged from the parking gear 4a, and the parking lock state is released (parking lock is released).

  An ECU (Electronic Control Unit) 10 has a CPU, ROM, RAM, A / D converter, input / output interface, and the like (not shown), and is based on detection signals from various sensors and the engine 1 and motor generators MG1, MG2. Control. Examples of various sensors include a brake pedal position sensor 32 that detects the depression amount of the brake pedal, a shift position sensor 31a that detects the operation position of the shift lever 31, and an acceleration sensor that detects the inclination and direction of the vehicle (so-called G sensor). 33). For example, the ECU 10 controls the brake 5 based on a detection signal from the brake pedal position sensor 32.

  In the present embodiment, the ECU 10 performs drive control of the motor generators MG1 and MG2 based on the detection signal from the shift position sensor 31a, the detection signal from the brake position sensor 32, and the detection signal from the acceleration sensor 33.

  FIG. 2 shows the configuration of the first and second motor generators MG1 and MG2, the power distribution mechanism 20, and the speed reducer 24 shown in FIG.

  The power distribution mechanism 20 is a mechanism that distributes the output torque of the engine 1 to the first motor generator MG1 and the output shaft 3, and is configured to generate a differential action. The reduction gear 24 is for decelerating the second motor generator MG2.

  In the present embodiment, as shown in FIG. 2, the power distribution mechanism 20 includes a ring gear 21, a carrier 22, and a sun gear 23. The reduction gear 24 includes a ring gear 25, a carrier 26, and a sun gear 27.

  The output shaft 2 of the engine 1 is connected to the carrier 22 of the power distribution mechanism 20, and the rotor 11 of the first motor generator MG 1 is connected to the sun gear 23 of the power distribution mechanism 20. The rotor 12 of the second motor generator MG2 is connected to the sun gear 27 of the speed reducer 24. The carrier 26 of the speed reducer 24 is fixed. The ring gear 21 of the power distribution mechanism 20 and the ring gear 25 of the speed reducer 24 are connected to each other and to the counter drive gear 28. The counter drive gear 28 is engaged with a counter driven gear 30 provided on the output shaft 3.

  A torque limiter 13 is provided on the output shaft 2 of the engine 1. Therefore, torque limiter 13 is connected between first motor generator MG1 and engine 1. The torque limiter 13 is for preventing excessive torque from the engine 1 from being transmitted to the power distribution mechanism 20. When an excessive torque is generated between the engine 1 and the motor generator MG1 due to a resonance phenomenon at the time of starting the engine 1, the torque limiter 13 absorbs this. The configurations of the power distribution mechanism 20 and the speed reducer 24 are not limited to the configurations shown in FIG. 2, and various configurations can be used.

  FIGS. 3A to 3C are schematic views showing the second motor generator MG2, the output shaft 3, and the drive wheels 9. FIG. FIG. 3A shows a schematic diagram when the hybrid vehicle is stopped on a slope in a parking lock state and in a brake-on state (a state in which a brake is applied), and FIG. FIG. 3C shows a schematic diagram when the hybrid vehicle is parked on the slope in the parking lock state and in the brake-off state (the brake is released). FIG. And the schematic diagram when the hybrid vehicle has stopped on the slope in the state of brake-off is shown.

  As shown to Fig.3 (a), the drive wheel 9 in a hybrid vehicle receives the torque from a slope. Specifically, the drive wheel 9 in the hybrid vehicle tends to rotate by torque from a slope. However, in this state, since the brake 5 is on, that is, the brake 5 is applied to the drive wheels 9, the torque from the slope has little influence on the output shaft 3. Here, as shown in FIG. 3 (b), when the brake 5 is in an off state, that is, when the brake 5 is not applied to the drive wheels 9, the output shaft 3 is in a park-locked state on the slope. And torque due to the weight of the hybrid vehicle itself are input. Therefore, the output shaft 3 is twisted. Then, as shown in FIG. 3C, when the parking lock pole 4b is released from the parking gear 4a and the parking lock is released, the torque due to its own weight and the impact torque due to the release of the twist of the output shaft 3 are released. Are input to the second motor generator MG2. This causes a vibration of the vehicle when the parking lock is released.

  Therefore, in the present embodiment, when the ECU 10 determines that the mode is such that the impact torque is generated when the parking lock is released, such as when the vehicle is on a slope in the parking lock state, the ECU 10 controls the second motor generator MG2. By outputting torque in the direction opposite to the direction of rotation when unlocking, the drive system connected to the second motor generator MG2 is loosened and the first motor generator MG1 is released when the parking lock is released. By outputting torque in the same direction as the rotation direction, the drive system connected to the first motor generator MG1 is loosened. Accordingly, the ECU 10 functions as a control device for the hybrid vehicle. Specifically, it functions as determination means and control means in the present invention. The details will be described below.

  Between the second motor generator MG2 and the drive wheels 9, there is a drive system backlash such as a backlash such as a gear or a spline. Therefore, ECU 10 causes second motor generator MG2 to output torque in a direction opposite to the direction of rotation caused by the impact torque when parking lock is released. As a result, the backlash of the drive system connected to the second motor generator MG2 is reduced, and the backlash of the drive system between the second motor generator MG2 and the drive wheels 9 is reduced. By doing so, it is possible to suppress the impact torque from being input to the second motor generator MG2.

  Further, ECU 10 causes first motor generator MG1 to output torque in the same direction as the direction of rotation caused by the impact torque when parking lock is released. As a result, the backlash of the drive system connected to the first motor generator is opened, and the drive system such as the backlash of the gear of the power distribution mechanism 20 existing between the output shaft 3 and the first motor generator MG1 is opened. The backlash is opened. By doing so, the impact torque is input to the first motor generator MG1.

  The first motor generator MG1 is mainly used as a generator, and the second motor generator MG2 is mainly used as an electric motor. Therefore, generally, the inertia of first motor generator MG1 is configured to be smaller than the inertia of second motor generator MG2. Therefore, as described above, the impact torque received by first motor generator MG1 can be reduced more than the impact torque received by second motor generator MG2. Further, as described above, torque limiter 13 is connected between first motor generator MG1 and engine 1. Therefore, the impact torque is also input to the torque limiter 13 when it is input to the first motor generator MG1. Thereby, the impact torque is absorbed by the torque limiter 13. That is, by receiving the impact torque by the first motor generator MG1, the impact torque can be absorbed also by the torque limiter 13 connected between the first motor generator MG1 and the engine 1, and the impact torque Can be reduced.

(Control processing according to this embodiment)
Next, control processing according to the present embodiment will be described using the flowchart shown in FIG.

  In step S101, the ECU 10 determines whether or not the operation position of the shift lever 31 is in the parking range based on the detection signal from the shift position sensor 31a. In step S101, when the ECU 10 determines that the operation position of the shift lever 31 is not in the parking range (step S101: No), the ECU 10 returns this control process. On the other hand, when the ECU 10 determines that the operation position of the shift lever 31 is in the parking range (step S101: Yes), the ECU 10 proceeds to the process of step S102.

  In step S <b> 102, the ECU 10 determines whether the hybrid vehicle is on a slope based on the detection signal from the acceleration sensor 33. In step S102, when the ECU 10 determines that the hybrid vehicle is not on the slope (step S102: No), the ECU 10 returns to the control process. On the other hand, when the ECU 10 determines that the hybrid vehicle is on a slope (step S102: Yes), the ECU 10 proceeds to the process of step S103. The process of step S102 is a process of determining whether or not a mode in which an impact torque is generated when the parking lock is released is determined.

  In step S103, the ECU 10 determines whether the hybrid vehicle is in an uphill state or a descending state based on a detection signal from the acceleration sensor 33. In other words, this process determines the rotation direction due to the impact torque when the parking lock is released for the first motor generator MG1 and the second motor generator MG2. Thus, ECU 20 can determine the direction in which torque is output to first motor generator MG1 and second motor generator MG2.

  In step S104, the ECU 10 determines whether or not the brake 5 is off based on the detection signal from the brake pedal position sensor 32. In step S104, if the ECU 10 determines that the brake 5 is off (step S104: Yes), the ECU 10 rotates the second motor generator MG2 in a direction opposite to the direction of rotation when the parking lock is released. By outputting torque, the drive system connected to the second motor generator MG2 is loosened. At the same time, the ECU 10 causes the first motor generator MG1 to output torque in the same direction as the rotation direction when the parking lock is released, thereby opening the backlash of the drive system connected to the first motor generator MG1. Is performed (step S105). Thus, when the parking lock is released, it is possible to suppress the input of impact torque to the second motor generator, and to input the impact torque to the first motor generator MG1 and the torque limiter 13. And impact torque can be reduced. Hereinafter, this control may be simply referred to as “backlash control”. Thereafter, the ECU 10 returns this control process.

  In step S104, when the ECU 10 determines that the brake 5 is not in the off state (step S104: No), the ECU 10 determines whether or not the MG play control described in step S105 is being executed (step S106). . If it is determined in step S106 that the MG backlash control is being executed (step S106: Yes), the ECU 10 returns this control process after continuing the MG backlash control. On the other hand, when it is determined in step S106 that the MG backlash control is not being executed (step S106: No), the ECU 10 returns this control process.

  As can be seen from the above description, in the present embodiment, in the parking lock state, when it is determined that the impact torque is generated when the parking lock is released, the ECU 10 causes the second motor generator MG2 to By outputting torque in the direction opposite to the direction of rotation when the parking lock is released, the drive system connected to the second motor generator MG2 is loosened and the parking lock is released for the first motor generator MG1. The backlash of the drive system connected to the first motor generator MG1 is performed by outputting torque in the same direction as the rotating direction. Thus, when the parking lock is released, it is possible to suppress the input of impact torque to the second motor generator, and to input the impact torque to the first motor generator MG1 and the torque limiter 13. And impact torque can be reduced. Moreover, by doing in this way, the static torque capacity of the second motor generator MG2 can be set small, and downsizing and cost reduction can be achieved.

[Modification]
Next, a hybrid vehicle control apparatus according to a modification will be described.

  FIG. 5 shows a schematic configuration of a drive mechanism of a hybrid vehicle according to a modification. In the hybrid vehicle drive mechanism according to the modification, unlike the hybrid vehicle drive mechanism according to the above-described embodiment, the parking lock mechanism 4 is configured to be driven and controlled by the ECU 10. Specifically, the ECU 10 performs drive control of the parking lock mechanism 4 by supplying a control signal to the parking lock mechanism 4 based on a detection signal from the shift position sensor 31a. For example, when the ECU 10 determines that the shift lever 31 is operated from the parking range to another range based on the detection signal from the shift position sensor 31a, that is, when it is determined that there is a parking release command from the driver. Supplies the parking lock mechanism 4 with a control signal for releasing the parking lock. The parking lock mechanism 4 that has received the control signal releases the parking lock by releasing the parking lock pole 4b from the parking gear 4a using an actuator (not shown).

  In the modified example, when the ECU 10 determines that the shock torque is generated when the parking lock is released, the ECU 10 receives the parking release command and releases the parking lock before the parking lock is released. Control is performed, that is, backlash is performed by causing the second motor generator MG2 to output torque, and backlash is performed by causing the first motor generator MG1 to output torque. Therefore, the ECU 10 also functions as a parking control means in the present invention. The details will be described below.

  In the hybrid vehicle drive mechanism according to the above-described embodiment, since the parking lock mechanism 4 is directly controlled by the driver, the ECU 10 recognizes when the parking lock is actually mechanically released. I can't. Therefore, in the above-described embodiment, the ECU 10 determines that the first motor generator MG1 and the second motor are from the time when it is determined that the brake 5 is off to the time when the parking lock is released. The generator MG2 needs to continue outputting torque for backlash control.

  However, in the hybrid vehicle drive mechanism according to the modified example, the ECU 10 performs drive control of the parking lock mechanism 4 based on the parking release command, that is, the ECU 10 mechanically controls the parking lock mechanism 4 itself. Release the parking lock. That is, the ECU 10 can recognize when the parking lock is actually released mechanically. Therefore, in the modification, when the ECU 10 determines that the mode in which the impact torque is generated when the parking lock is released is entered, the ECU 10 is the embodiment described above after receiving the parking release command and before releasing the parking lock. The backlash control is performed.

  By doing so, the parking lock release is performed after the parking release command is received for the time for the first motor generator MG1 and the second motor generator MG2 to output torque for backlash control. Can be between. That is, as compared with the above-described embodiment, the time for outputting torque for backlash control to the first motor generator MG1 and the second motor generator MG2 can be shortened. The loss due to can be minimized.

(Control processing according to modification)
Next, control processing according to the modification will be described with reference to the flowchart shown in FIG.

  The processing from step S201 to step S203 is the same as the processing from step S101 to step S103 in the flowchart shown in FIG.

  In step S204, the ECU 10 determines whether or not the brake 5 is off based on the detection signal from the brake pedal position sensor 32. In step S204, when the ECU 10 determines that the brake 5 is in the off state (step S204: Yes), the process proceeds to step S205.

  In step S205, the ECU 10 performs control execution determination as to whether or not to perform backlash control. Specifically, the ECU 10 determines whether or not the shift lever 31 has been operated from the parking range to another range based on the detection signal from the shift position sensor 31a, that is, whether or not there is a parking cancellation command from the driver. Determine whether. Thereafter, the ECU 10 proceeds to the process of step S207.

  In step S204, when the ECU 10 determines that the brake 5 is not in the off state (step S204: No), the ECU 10 determines whether or not the control execution determination described in step S205 has been performed (step S206). . If it is determined in step S206 that the control execution determination has been made (step S206: Yes), the ECU 10 proceeds to the process to step S207. On the other hand, when the ECU 10 determines that the control execution determination has not been made (step S206: No), the ECU 10 returns this control process.

  In step S207, if the ECU 10 determines that the shift lever 31 has been operated from the parking range to another range, that is, if there is a parking cancellation command from the driver, the process of step S208 is performed. If it is determined that there is no parking release command, the control process is returned.

  In step S208, the ECU 10 performs backlash by causing the second motor generator MG2 to output torque, and performs backlash by causing the first motor generator MG1 to output torque. Thereafter, in step S209, the ECU 10 transmits a control signal to the parking lock mechanism 4 to release the mechanical parking lock. That is, the ECU 10 transmits the control signal to the parking lock mechanism 4 to release the parking lock pole 4b from the parking gear 4a.

  As can be seen from the above description, in the modified example, when the ECU 10 determines that the shock torque is generated when the parking lock is released, the ECU 10 receives the parking release command and before the parking lock is released. In addition, backlash is performed by causing the second motor generator MG2 to output torque, and backlash is performed by causing the first motor generator MG1 to output torque. By doing in this way, compared with the embodiment described above, the time for outputting torque for backlash control to the first motor generator MG1 and the second motor generator MG2 is shortened. And the loss due to backlash control can be minimized.

It is a schematic diagram of the drive mechanism of the hybrid vehicle which concerns on this embodiment. The structure of the 1st and 2nd motor generator, a power distribution mechanism, and a reduction gear is shown. It is a schematic diagram which shows a 2nd motor generator, an output shaft, and a driving wheel. It is a flowchart which shows the control processing which concerns on this embodiment. It is a schematic diagram of the drive mechanism of the hybrid vehicle which concerns on a modification. It is a flowchart which shows the control processing which concerns on a modification.

Explanation of symbols

MG1, MG2 Motor generator 1 Engine 3 Output shaft 4 Parking lock mechanism 5 Brake 9 Drive wheel 10 ECU
13 Torque limiter 20 Power distribution mechanism 24 Reducer 31 Shift brake 32 Brake pedal 33 Acceleration sensor

Claims (2)

First and second motor generators, a power distribution mechanism connected to the first and second motor generators, drive wheels connected to the power distribution mechanism, the first motor generator and an internal combustion engine A control device for a hybrid vehicle having a torque limiter connected between
Determining means for determining whether or not to enter a mode in which an impact torque is generated when the parking lock is released;
In the parking lock state, if the determination means determines that an impact torque is generated when the parking lock is released, torque is applied to the second motor generator in a direction opposite to the direction of rotation when the parking lock is released. Is output, the drive system connected to the second motor generator is loosened, and the first motor generator is caused to output torque in the same direction as the rotation direction when the parking lock is released. And a control means for opening the drive system connected to the first motor generator. Upon receiving a parking release command from the driver, the parking control means for releasing the parking lock is provided,
In the case where it is determined by the determination means that the control means is in a mode in which an impact torque is generated when the parking lock is released, after the parking control means receives the parking release command and before releasing the parking lock, 2. The control device for a hybrid vehicle according to claim 1, wherein the loosening is performed by causing the second motor generator to output torque and performing the loosening by causing the first motor generator to output torque. 3.

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