JP2008213567A - Power train control device, control method, program for realizing the method, and record medium recording the program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the rotational frequency of a sun gear connected to a first MG from becoming excessively high. <P>SOLUTION: The first MG is connected to the sun gear of a power dividing mechanism. An automatic transmission is connected to a ring gear. An engine is connected to a carrier. An ECU executes a program including: a step (S102) of controlling an automatic transmission to start formation of a forward gear step or a backward gear step when the shift operation from N position to D position or from N position to R position is performed (YES in S100); a step (S104) of determining whether or not the engine is started; and a step (S112) of controlling the engine to start ignition when the engine rotational frequency NE becomes larger than a threshold in the process of forming a gear step (YES in S110) in the case where starting of the engine is decided (YES in S102). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a power train control device, a control method, a program for realizing the method, and a recording medium storing the program, and in particular, starts an engine when a shift operation from a non-travel position to a travel position is performed. Related to technology.

  Conventionally, a hybrid vehicle having an engine and a rotating electric machine as drive sources is known. In such a hybrid vehicle, an engine and a rotating electric machine are selectively used according to the traveling state of the vehicle. For example, the vehicle travels mainly using an engine when traveling at a high speed, and travels mainly using a rotating electrical machine when traveling at a medium or low speed. One such hybrid vehicle includes a multi-stage automatic transmission in addition to a differential mechanism that functions as a continuously variable transmission using a rotating electrical machine.

  Japanese Patent Laying-Open No. 2005-337491 (Patent Document 1) includes a first element coupled to an engine, a second element coupled to a first electric motor (rotating electric machine), and a third element coupled to a second electric motor. Control of a vehicle drive device comprising a continuously variable transmission having a configured differential mechanism and functioning as an electric continuously variable transmission, and a transmission provided between the continuously variable transmission and the wheels An apparatus is disclosed. In the control device described in Patent Document 1, the gear of the continuously variable transmission unit is synchronized with the shift so that the gear ratio formed by the continuously variable transmission unit and the transmission unit is continuous when the transmission unit shifts. Including a continuously variable transmission control unit.

According to the control device described in this publication, the gear ratio formed by the continuously variable transmission unit and the transmission unit, that is, the gear ratio formed based on the transmission ratio of the continuously variable transmission unit and the transmission gear ratio. The overall gear ratio is continuously changed. As a result, the engine speed (the number of revolutions) is continuously changed before and after the speed change of the speed change unit to reduce the speed change shock.
JP 2005-337491 A

  By the way, when a multi-stage automatic transmission is connected to the differential mechanism, when the multi-stage automatic transmission is switched from a neutral state to a state in which a gear stage is formed, the rotation of the rotary element connected to the input shaft of the multi-stage automatic transmission The number changes step by step. Due to the characteristics of the differential mechanism, when the rotational speed of at least one of the three rotational elements changes, the rotational speed of the other rotational elements changes. Therefore, when the rotational speed of the rotary element connected to the input shaft of the multi-stage automatic transmission changes stepwise, the rotational speed of the rotary element different from the rotary element connected to the engine is used with the engine speed as a fulcrum in the alignment chart. The number changes greatly. At this time, depending on the engine speed, the rotational speed of the rotating element may be excessively high. For example, when the rotational speed of the rotary element connected to the input shaft of the multi-stage automatic transmission increases stepwise, if the engine speed is “0”, the rotational speed is different from that of the rotary element connected to the engine. The rotational speed of the element increases in the opposite direction to the rotational element connected to the input shaft of the multi-stage automatic transmission. However, Japanese Patent Application Laid-Open No. 2005-337491 has no description regarding such a problem.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to control a power train, a control method, and a method thereof that can prevent the rotational speed of a rotating element from becoming excessively high. And a recording medium on which the program is recorded.

  A power train control device according to a first aspect of the present invention includes a first rotating element, a second rotating element, and a third rotating element, and another rotating element according to the rotational speed of any one of the rotating elements. A state in which a differential mechanism in which the number of revolutions changes, a rotating electrical machine coupled to the first rotating element, a torque coupled to the second rotating element and transmitting torque input from the second rotating element to the wheels, and A control apparatus for a power train, comprising: a switching mechanism capable of switching a state of interrupting transmission of torque from the second rotating element to the wheel; and an engine coupled to the third rotating element. When the shift operation from the non-traveling position to the traveling position is performed, the control device switches from a state in which the transmission of torque from the second rotating element to the wheel is interrupted to a state in which the torque is transmitted to the wheel. In addition, a means for controlling the switching mechanism, a determination means for determining whether or not to start the engine when a shift operation from the non-travel position to the travel position is performed, and a determination to start the engine If the engine output shaft rotational speed becomes larger than the threshold value during switching from the state in which the transmission of torque from the second rotating element to the wheel is interrupted to the state in which the torque is transmitted to the wheel, And control means for controlling the engine to start the operation. The power train control method according to the fourth invention has the same requirements as those of the power train control device according to the first invention.

  According to the first or fourth invention, the differential mechanism has a first rotating element, a second rotating element, and a third rotating element. The number of rotations of the first rotation element changes according to the number of rotations of the second rotation element and the third rotation element. A rotating electrical machine is coupled to the first rotating element. A switching mechanism is coupled to the second rotating element. The switching mechanism can switch between a state in which torque input from the second rotating element is transmitted to the wheel and a state in which transmission of torque from the second rotating element to the wheel is interrupted. An engine is connected to the third rotating element. When a shift operation from the non-traveling position to the traveling position is performed, the switching mechanism is switched from a state in which transmission of torque from the second rotating element to the wheel is interrupted to a state in which torque is transmitted to the wheel. Further, when a shift operation from the non-travel position to the travel position is performed, it is determined whether or not to start the engine. If it is determined that the engine is to be started, the engine output shaft rotational speed is greater than the threshold value during switching from the state where the torque transmission from the second rotating element to the wheel is interrupted to the state where the torque is transmitted to the wheel. Then, ignition in the engine is started. As a result, the engine can be started quickly by cranking the engine using the force that increases the rotational speed of the third rotating element via the second rotating element connected to the switching mechanism. it can. Therefore, even when the rotational speed of the second rotating element changes stepwise by switching from the state where the transmission of torque to the wheel is interrupted to the state where the torque is transmitted to the wheel, The engine speed can be adjusted by the engine so that the engine speed does not become excessively high. As a result, it is possible to provide a control apparatus or control method for a power train that can prevent the rotational speed of the rotating element from becoming excessively high.

  In addition to the configuration of the first invention, the power train control device according to the second invention is arranged in the same direction as the rotation direction of the third rotating element during the operation of the engine before starting ignition in the engine. Means for controlling the rotating electrical machine such that a force acts on the rotating element of the motor. The power train control method according to the fifth invention has the same requirements as the power train control device according to the second invention.

  According to the second or fifth aspect of the invention, before starting ignition in the engine, the rotating electrical machine is such that a force acts on the third rotating element in the same direction as the rotating direction of the third rotating element during operation of the engine. Is controlled. Thereby, the rotation speed of the engine connected to the third rotation element can be increased more rapidly. Therefore, the engine can be started more quickly.

  In the power train control device according to the third invention, in addition to the configuration of the first or second invention, the first rotating element is a sun gear. The second rotating element is a ring gear. The third rotating element is a carrier that rotatably supports a pinion gear that meshes with the sun gear and the ring gear. The power train control method according to the sixth invention has the same requirements as those of the power train control device according to the third invention.

  According to the third or sixth aspect of the invention, in the differential mechanism having the sun gear connected to the rotating electrical machine, the ring gear connected to the switching mechanism, and the carrier connected to the engine, the rotational speed of the sun gear is prevented from becoming excessive. be able to.

  A program according to a seventh invention is a program for causing a computer to realize the control method according to any of the fourth to sixth inventions, and the recording medium according to the eighth invention is any one of the fourth to sixth inventions. It is a computer-readable recording medium which recorded the program which makes a computer implement | achieve the control method concerning.

  According to the seventh or eighth invention, the power train control method according to any of the fourth to sixth inventions can be realized using a computer (which may be general purpose or dedicated).

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  A hybrid vehicle equipped with a control device according to an embodiment of the present invention will be described with reference to FIG. This hybrid vehicle is an FR (Front engine Rear drive) vehicle. A vehicle other than FR may be used.

  The hybrid vehicle includes a hybrid system 100 as a drive source, an automatic transmission 400, a propeller shaft 500, a differential gear 600, a rear wheel 700, and an ECU (Electronic Control Unit) 800. The control device according to the present embodiment is realized, for example, by executing a program recorded in ROM (Read Only Memory) 802 of ECU 800. The program executed by ECU 800 may be recorded on a recording medium such as a CD (Compact Disc) or a DVD (Digital Versatile Disc) and distributed to the market. ECU 800 may be divided into a plurality of ECUs.

  The hybrid vehicle power train includes a hybrid system 100 and an automatic transmission 400. The engine 200 of the hybrid system 100 is an internal combustion engine that burns a mixture of fuel and air injected from an injector 202 in a combustion chamber of a cylinder. The piston in the cylinder is pushed down by the combustion, and the crankshaft is rotated.

  Automatic transmission 400 is coupled to the output shaft of hybrid system 100. The driving force output from the automatic transmission 400 is transmitted to the left and right rear wheels 700 via the propeller shaft 500 and the differential gear 600.

  The ECU 800 includes a position switch 806 for the shift lever 804, an accelerator opening sensor 810 for the accelerator pedal 808, a depression force sensor 814 for the brake pedal 812, a throttle opening sensor 818 for the electronic throttle valve 816, and an engine speed sensor 820. The input shaft speed sensor 822, the output shaft speed sensor 824, and the oil temperature sensor 826 are connected via a harness or the like.

  The position (position) of shift lever 804 is detected by position switch 806, and a signal representing the detection result is transmitted to ECU 800. Corresponding to the position of the shift lever 804, a shift in the automatic transmission 400 is automatically performed. By operating the shift lever 804, the driver may be able to select a desired gear (gear ratio).

  Accelerator opening sensor 810 detects the opening of accelerator pedal 808 and transmits a signal representing the detection result to ECU 800. The pedaling force sensor 814 detects the pedaling force of the brake pedal 812 (the force with which the driver steps on the brake pedal 812), and transmits a signal representing the detection result to the ECU 800.

  The throttle opening sensor 818 detects the opening of the electronic throttle valve 816 whose opening is adjusted by the actuator, and transmits a signal indicating the detection result to the ECU 800. The electronic throttle valve 816 adjusts the amount of air taken into the engine 200 (output of the engine 200).

  Instead of or in addition to the electronic throttle valve 816, the amount of air sucked into the engine 200 is changed by changing the lift amount of the intake valve (not shown) or the exhaust valve (not shown) and the opening / closing phase. You may make it adjust.

  Engine rotation speed sensor 820 detects the rotation speed (engine rotation speed NE) of the output shaft (crankshaft) of engine 200 and transmits a signal representing the detection result to ECU 800. Input shaft speed sensor 822 detects input shaft speed NI of automatic transmission 400 and transmits a signal representing the detection result to ECU 800. Output shaft rotational speed sensor 824 detects output shaft rotational speed NO of automatic transmission 400 and transmits a signal representing the detection result to ECU 800.

  The vehicle speed of the hybrid vehicle is calculated from the output shaft rotational speed NO of automatic transmission 400. In addition, about the method of calculating a vehicle speed, what is necessary is just to use a known general technique, Therefore The detailed description is not repeated here.

  Oil temperature sensor 826 detects the temperature (oil temperature) of oil (ATF: Automatic Transmission Fluid) used for the operation and lubrication of automatic transmission 400 and transmits a signal representing the detection result to ECU 800.

  ECU 800 is sent from position switch 806, accelerator opening sensor 810, pedal effort sensor 814, throttle opening sensor 818, engine speed sensor 820, input shaft speed sensor 822, output shaft speed sensor 824, oil temperature sensor 826, and the like. Based on the received signal, the map stored in the ROM 802, and the program, the devices are controlled so that the vehicle is in a desired running state.

  The hybrid system 100 and the automatic transmission 400 will be further described with reference to FIG.

  Hybrid system 100 includes an engine 200, a power split mechanism 310, a first MG (Motor Generator) 311, and a second MG 312. Power split device 310 splits the output of engine 200 input to input shaft 302 into first MG 311 and output shaft 304. Power split device 310 includes planetary gear 320.

  Planetary gear 320 includes a sun gear 322, a pinion gear 324, a carrier 326 that supports the pinion gear 324 so as to rotate and revolve, and a ring gear 328 that meshes with the sun gear 322 via the pinion gear 324.

  In power split device 310, carrier 326 is connected to input shaft 302, that is, engine 200. Sun gear 322 is connected to first MG 311. Ring gear 328 is coupled to output shaft 304.

  Power split device 310 functions as a differential device by relatively rotating sun gear 322, carrier 326, and ring gear 328. Due to the differential function of power split device 310, the output of engine 200 is distributed to first MG 311 and output shaft 304.

  The first MG 311 generates electric power using a part of the output of the distributed engine 200, or the second MG 312 is rotationally driven using electric power generated by the first MG 311 so that the power split mechanism 310 is a continuously variable transmission. Function as.

  First MG 311 and second MG 312 are three-phase AC rotating electric machines. First MG 311 is coupled to sun gear 322 of power split device 310. Second MG 312 is provided such that the rotor rotates integrally with output shaft 304.

  First MG 311 and second MG 312 are controlled so as to satisfy the target output torque of automatic transmission 400 calculated from, for example, the accelerator opening and the vehicle speed, and to realize optimum fuel consumption in engine 200. The output torque of second MG 312 is determined according to a map that defines the ratio of the output torque of engine 200 and the output torque of second MG 312 to the target output torque.

  As shown in FIG. 3, the rotational speed of first MG 311, the rotational speed of second MG 312, and engine rotational speed NE are in a relationship connected by a straight line in the nomographic chart. Therefore, as indicated by the alternate long and short dash line in FIG. 3, when the rotation speed of the second MG 312 changes, the rotation speed of the first MG 311 changes. Further, as indicated by a two-dot chain line in FIG. 3, the rotational speed of the first MG 311 changes according to the engine rotational speed NE.

  In the present embodiment, the ring gear when the hybrid vehicle is moving forward in the state where the forward gear stage is formed in the automatic transmission 400 or when the vehicle is moving backward while the reverse gear stage is formed. The rotational speed NR is expressed as a positive value. That is, in the automatic transmission 400, the rotational direction of the ring gear 328 is the same when the hybrid vehicle is moving forward when the forward gear is formed and when the hybrid vehicle is moving backward when the reverse gear is formed. .

  When the hybrid vehicle is moving backward in a state where the forward gear stage is formed in the automatic transmission 400, or when the hybrid vehicle is moving forward in a state where the reverse gear stage is formed, the ring gear rotational speed NR becomes a negative value.

  In addition, as shown in FIG. 4, in the present embodiment, the rotation direction during operation of engine 200 (the rotation direction of carrier 326 during operation of engine 200) and the ring gear when ring gear rotation speed NR is a positive value. The direction of rotation of 328 is the same.

  In the present embodiment, first MG 311, second MG 312, and engine 200 are configured so as to protect power train, so that rotation speed NR of ring gear 328 of power split mechanism 310 (input shaft speed NI of automatic transmission 400) and engine speed NE (The rotation speed of the carrier 326) is controlled so as to be within an allowable region indicated by hatching in FIG.

  The allowable range is determined in consideration of the lower limit value NSL, the upper limit value NSH, the lower limit value PINL and the upper limit value PINH of the rotation speed of the first MG 311 (the rotation speed of the sun gear 322) of the pinion gear 324. That is, the first MG 311, the second MG 312, and the first MG 311 so that the rotation speed of the first MG 311 is not less than the lower limit value NSL and not more than the upper limit value NSH and the rotation speed of the pinion gear 324 is not less than the lower limit value PINL and not more than the upper limit value PINH. The engine 200 is controlled. The rotation speed of the pinion gear 324 is a relative rotation speed between the rotation speed NR of the ring gear 328 and the rotation speed of the carrier 326.

  Returning to FIG. 2, the automatic transmission 400 includes an input shaft 404 as an input rotating member disposed on a common axis in a case 402 as a non-rotating member attached to the vehicle body, and an output as an output rotating member. Axis 406.

  Input shaft 404 is connected to output shaft 304 of power split device 310. Therefore, the input shaft rotational speed NI of automatic transmission 400 and the output shaft rotational speed of power split device 310, that is, the rotational speed of ring gear 328 (the rotational speed of second MG 312) NR are the same.

  Automatic transmission 400 includes three planetary gears 411 to 413 of a single pinion type, and five friction engagement elements of C1 clutch 421, C2 clutch 422, B1 brake 431, B2 brake 432, and B3 brake 433.

  By engaging the friction engagement elements of the automatic transmission 400 in the combinations shown in the operation table shown in FIG. 6, the five forward gears and the reverse gears of the first gear to the fifth gear with different gear ratios are arranged in the power train. A gear stage is formed.

  In a state where the gear stage is formed in automatic transmission 400, torque (output torque of hybrid system 100) input from ring gear 328 of power split mechanism 310 to automatic transmission 400 is transmitted to rear wheel 700 that is a drive wheel.

  When the shift lever 804 is in a travel position such as the D (drive) position or the R (reverse) position and the travel range is selected, a gear stage is formed in the power train.

  On the other hand, when shift lever 804 is in a non-traveling position such as an N (neutral) position and the non-traveling range is selected, automatic transmission 400 is set to the neutral state.

  In the neutral state of automatic transmission 400, all the frictional engagement elements are released. In the neutral state, transmission of torque from the ring gear 328 of the power split mechanism 310 to the rear wheel 700 is interrupted.

  As shown in FIG. 6, the friction engagement element that is engaged when forming the fourth speed gear stage and the friction engagement element that is engaged when forming the fifth speed gear stage are the same. That is, the gear ratio in automatic transmission 400 is the same between the fourth gear and the fifth gear. However, the gear ratio in power split mechanism 310 is different.

  When the 4-speed gear stage is formed, the power split mechanism 310 allows the rotation of the first MG 311 so that the engine speed and the output shaft 304 are the same, and the gear ratio is “1”. On the other hand, when forming the fifth gear, the rotation speed of the first MG 311 is set to “0”, so that the rotation speed of the output shaft 304 is made higher than the engine rotation speed, and the transmission ratio is set to “1”. Is also made smaller.

  The shift in the power train is controlled based on, for example, a shift diagram shown in FIG. The shift map in the present embodiment is determined by using the target output torque calculated from the accelerator opening and the vehicle speed, and the vehicle speed as parameters. Note that the parameters of the shift map are not limited to these.

  A solid line in FIG. 7 is an upshift line, and a broken line is a downshift line. In FIG. 7, a region surrounded by a one-dot chain line indicates a region that travels using only the driving force of the second MG 312 without using the driving force of the engine 200.

  The C1 clutch 421, the C2 clutch 422, the B1 brake 431, the B2 brake 432, and the B3 brake 433 of the automatic transmission 400 are operated by hydraulic pressure. In the present embodiment, as shown in FIG. 8, the hybrid vehicle is provided with a hydraulic control device 900 that supplies / discharges hydraulic pressure to / from each friction engagement element and controls engagement / release.

  The hydraulic control apparatus 900 adjusts the hydraulic pressure generated by the mechanical oil pump 910, the electric oil pump 920, and the oil pumps 910 and 920 to the line pressure, and the hydraulic pressure adjusted using the line pressure as the original pressure. And a hydraulic circuit 930 that supplies oil for lubrication to an appropriate location.

  Mechanical oil pump 910 is a pump that is driven by engine 200 to generate hydraulic pressure. The mechanical oil pump 910 is disposed coaxially with the carrier 326 and is operated by receiving torque from the engine 200. That is, when the carrier 326 rotates, the mechanical oil pump 910 is driven, and hydraulic pressure is generated.

  On the other hand, the electric oil pump 920 is a pump driven by a motor (not shown). The electric oil pump 920 is attached to an appropriate location such as the outside of the transmission case. Electric oil pump 920 is controlled by ECU 800 to generate a desired oil pressure. For example, the rotational speed of the electric oil pump 920 is feedback-controlled.

  The rotational speed of electric oil pump 920 is detected by rotational speed sensor 830, and a signal representing the detection result is transmitted to ECU 800. Further, the discharge pressure from the electric oil pump 920 is detected by the hydraulic sensor 832, and a signal indicating the detection result is transmitted to the ECU 800.

  The electric oil pump 920 is operated by electric power supplied from the battery 942 via the DC / DC converter 940. The electric power of the battery 942 is supplied not only to the electric oil pump 920 but also to auxiliary devices that are operated by electric power, such as the electric power steering 950, the first MG 312 and the second MG 312.

  The charge / discharge current value from battery 942 is detected by current sensor 834, and a signal representing the detection result is transmitted to ECU 800. In the present embodiment, the SOC (State Of Charge) of battery 942 is calculated based on the charge / discharge current value from battery 942. In addition, since it is sufficient to use a known general technique for calculating the SOC, detailed description thereof will not be repeated here. The temperature of battery 942 is detected by temperature sensor 836 and a signal representing the detection result is transmitted to ECU 800.

  The hydraulic circuit 930 includes a plurality of solenoid valves, switching valves, or pressure regulating valves (each not shown), and is configured to be able to electrically control pressure regulation and hydraulic supply / discharge. The control is performed by the ECU 800.

  In addition, check valves 912 and 922 that open at the discharge pressure of the oil pumps 910 and 920 and close in the opposite direction are provided on the discharge side of the oil pumps 910 and 920, and the hydraulic circuit 930 includes On the other hand, these oil pumps 910 and 920 are connected in parallel to each other. In addition, a valve (not shown) that regulates the line pressure increases the discharge amount to increase the line pressure, and conversely controls the line pressure to reduce the discharge amount to lower the line pressure. Is configured to do.

  With reference to FIG. 9, the function of ECU 800 serving as the control device according to the present embodiment will be described. The functions of ECU 800 described below may be realized by hardware or may be realized by software.

  ECU 800 includes a shift operation determination unit 840, an engagement unit 842, a start determination unit 844, a first MG control unit 846, an engine speed determination unit 848, and an ignition start unit 850.

  The shift operation determination unit 840 determines whether or not a shift operation from the N position to the D position (operation of the shift lever 804) or a shift operation from the N position to the R position has been performed.

  Whether or not a shift operation from the N position to the D position or from the N position to the R position has been performed is determined based on a signal transmitted from the position switch 806. Note that the method of determining whether or not a shift operation has been performed is not limited to this.

  When the shifting operation from the N position to the D position or from the N position to the R position is performed, the engaging portion 842 starts to form a gear stage, that is, to engage the clutch and the brake that are friction engagement elements. The automatic transmission 400 is controlled. Therefore, the neutral state is switched to a state in which the torque of the ring gear 328 is transmitted to the rear wheel 700.

  The start determination unit 844 determines whether or not to start the engine 200 to protect the power train when a shift operation from the N position to the D position or from the N position to the R position is performed.

  Whether engine 200 is to be started depends on, for example, an estimated value of rotation speed NR (input shaft rotation speed NI of automatic transmission 400) of ring gear 328 of power split mechanism 310, engine rotation speed NE (rotation speed of carrier 326), and so on. Is determined based on

  If the estimated value of the rotational speed NR of the ring gear 328 and the engine rotational speed NE are within the start region indicated by hatching in FIG. 10, it is determined that the engine 200 is started. The starting region is a region where the ring gear rotational speed NR is larger than the allowable region shown in FIG. The start area is not limited to this.

  The estimated value of the ring gear rotational speed NR is calculated by multiplying the output shaft rotational speed NO of the automatic transmission 400 by the gear ratio. An actual measurement value may be used instead of the estimated value of the ring gear rotation speed NR.

  Before starting ignition in engine 200 (before starting engine 200), first MG control unit 846 causes force to act on carrier 326 in the same direction as the direction of rotation of carrier 326 during operation of engine 200. The first MG 311 is controlled. That is, first MG 311 is controlled such that torque is output in a direction in which the rotation speeds of carrier 326 and sun gear 322 increase.

  Based on the signal transmitted from engine speed sensor 820, engine speed determination unit 848 determines whether engine speed NE is greater than a threshold value. Ignition start unit 850 causes engine 200 to start ignition in engine 200 when engine speed NE is greater than the threshold value during the formation of the gear stage (after the start of the gear stage formation and before the completion). Control. When ignition is started, engine 200 is started.

  Whether the gear stage is being formed is, for example, whether the difference between the input shaft rotational speed NI of the automatic transmission 400 and the value calculated by multiplying the output shaft rotational speed NO by the gear ratio is greater than a threshold value. It is judged by whether or not. Note that the method for determining whether or not the gear stage is being formed is not limited to this.

  With reference to FIG. 11, a control structure of a program executed by ECU 800 serving as the control apparatus according to the present embodiment will be described. The program described below is repeatedly executed at a predetermined cycle.

  In step (hereinafter, step is abbreviated as S) 100, ECU 800 determines whether or not a shift operation from the N position to the D position or from the N position to the R position is performed based on a signal transmitted from position switch 806. Judging.

  When a shift operation from the N position to the D position or from the N position to the R position is performed (YES in S100), the process proceeds to S102. Otherwise (NO in S100), this process ends.

  In S102, ECU 800 controls automatic transmission 400 to start the formation of the forward gear stage or the reverse gear stage, that is, the engagement of the friction engagement element. That is, the neutral state is switched to a state in which the torque of the ring gear 328 is transmitted to the rear wheel 700. When a shift operation from the N position to the D position is performed, a forward gear stage is formed. When a shift operation from the N position to the R position is performed, a reverse gear stage is formed.

  In S104, ECU 800 determines whether or not to start engine 200 based on rotation speed NR and engine rotation speed NE of ring gear 328 of power split mechanism 310 when engine 200 is stopped. If it is determined that engine 200 is to be started (YES in S104), the process proceeds to S106. Otherwise (NO in S104), this process ends.

  In S106, ECU 800 determines whether or not ring gear rotation speed NR detected using input shaft rotation speed sensor 822 is a positive value. If ring gear rotation speed NR is a positive value (YES in S106), the process proceeds to S108. If not (NO in S106), the process returns to S104.

  In S108, ECU 800 controls first MG 311 such that a force acts on carrier 326 in the same direction as the rotation direction of carrier 326 during operation of engine 200. That is, first MG 311 is controlled to output torque in a direction in which the rotation speeds of carrier 326 and sun gear 322 increase.

  In S110, ECU 800 determines whether or not engine speed NE has become greater than a threshold value during the formation of the gear stage (while the friction engagement element is engaged). When engine speed NE is greater than the threshold value (YES in S110), the process proceeds to S112. If not (NO in S110), the process returns to S110.

  In S112, ECU 800 controls engine 200 to start ignition in engine 200. That is, engine 200 is started.

  An operation of ECU 800 serving as the control device according to the present embodiment based on the above-described structure and flowchart will be described.

  Here, it is assumed that the shift operation to the N position is performed and the engine 200 is stopped. After the shift operation to the N position is performed, for example, when the shift operation from the N position to the D position is performed during forward movement or the shift operation from the N position to the R position is performed during reverse travel (YES in S100), The automatic transmission 400 is controlled to start the formation of the forward gear or the reverse gear (S102).

  As indicated by black dots in FIG. 12, when the estimated value of the rotational speed NR of the ring gear 328 calculated by multiplying the output shaft rotational speed NO of the automatic transmission 400 by the gear ratio and the engine rotational speed NE are within the start range, When the gear stage is formed, the actual ring gear rotation speed NR increases as shown in FIG. If engine 200 remains stopped, the rotational speed of first MG 311, that is, the absolute value of the rotational speed of sun gear 322 of power split device 310 may become excessively high.

  In this case, it is determined that engine 200 is started (YES in S104). If ring gear rotation speed NR is a positive value (YES in S106), it can be said that gear formation, that is, engagement of friction engagement elements has started.

  Therefore, as shown in FIG. 14, the ring gear rotational speed NR increases. As the ring gear rotational speed NR increases, the engine rotational speed NE (the rotational speed of the carrier 326) is increased.

  If engine speed NE is greater than the threshold value during the formation of gear stage (YES in S110), engine 200 is controlled to start ignition in engine 200 (S112). That is, engine 200 is started.

  As a result, the engine 200 can be quickly started by cranking the engine 200 using the force that increases the rotational speed of the carrier 326 via the ring gear 328 of the power split mechanism 310. Therefore, as shown in FIG. 15, the engine speed NE can be increased to reduce the rotational speed of the first MG 311, that is, the absolute value of the rotational speed of the sun gear 322 of the power split mechanism 310.

  In the present embodiment, when ring gear rotation speed NR is a positive value (YES in S106), as shown by an arrow in FIG. 16, engine 200 is in operation before starting ignition in engine 200. The first MG 311 is controlled so that a force acts on the carrier 326 in the same direction as the rotation direction of the carrier 326 (S108).

  As a result, the engine speed NE can be quickly increased using the torque output by the first MG 311. Therefore, engine 200 can be started more quickly.

  As described above, according to the ECU that is the control apparatus according to the present embodiment, when the shift operation from the N position to the D position or from the N position to the R position is performed, the forward gear stage or the reverse gear stage is formed. The automatic transmission is controlled to start. When a shift operation is performed, it is determined whether or not to start the engine. If it is determined that the engine is to be started, ignition in the engine is started when the engine speed NE becomes greater than the threshold value during the gear stage formation. As a result, the engine can be quickly started by cranking the engine using the force that increases the rotational speed of the carrier via the ring gear of the power split mechanism. Therefore, even when the ring gear rotational speed NR increases due to the formation of the gear stage, the engine rotational speed NE is increased to obtain the absolute value of the rotational speed of the first MG, that is, the rotational speed of the sun gear of the power split mechanism. Can be small.

  In addition, instead of making it possible to form five forward gears in the power train, four forward gears from the first gear to the fourth gear may be formed. When the power train is configured so as to be able to form four forward gears, as shown in FIG. 17, the automatic transmission 400 includes two single-pinion type planetary gears 441 and 442, a C1 clutch 451, and a C2 clutch 452. , Four friction engagement elements of B1 brake 461 and B2 brake 462.

  By engaging the friction engagement elements in the combinations shown in the operation table shown in FIG. 18, four forward gears from the first gear to the fourth gear are formed.

  The friction engagement element that is engaged when forming the third speed gear stage is the same as the friction engagement element that is engaged when forming the fourth speed gear stage. That is, the gear ratio in automatic transmission 400 is the same between the third gear and the fourth gear. However, the gear ratio in power split mechanism 310 is different.

  When the third speed gear stage is formed, the power split mechanism 310 allows the first MG 311 to rotate, the engine speed and the output shaft 304 are made the same, and the gear ratio is “1”. On the other hand, when the 4-speed gear stage is formed, the rotational speed of the first MG 311 is set to “0”, so that the rotational speed of the output shaft 304 is made higher than the engine rotational speed, and the transmission ratio is set to “1”. Is also made smaller. The shift in the power train is controlled based on, for example, a shift diagram shown in FIG.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a schematic block diagram which shows the hybrid vehicle carrying the control apparatus which concerns on embodiment of this invention. It is a figure (the 1) which shows a hybrid system and an automatic transmission. It is a figure (the 1) which shows the alignment chart of a power split device. FIG. 8 is a second diagram showing a nomographic chart of the power split mechanism. FIG. 6 is a diagram (No. 1) showing an allowable range defined from a lower limit value and an upper limit value of the rotation speed of MG1. It is a figure (the 1) which shows an operation | movement table | surface. FIG. 3 is a diagram (part 1) illustrating a shift diagram. It is a figure which shows a hydraulic control apparatus. It is a functional block diagram of ECU. It is FIG. (1) which shows the starting area | region used in order to judge whether an engine is started. It is a flowchart which shows the control structure of the program which ECU performs. FIG. 10 is a diagram (No. 2) showing a start region used for determining whether or not to start the engine. FIG. 9 is a third diagram illustrating a nomographic chart of the power split mechanism. FIG. 6 is a diagram (No. 4) illustrating an alignment chart of a power split mechanism; FIG. 10 is a fifth diagram showing a nomographic chart of the power split mechanism; It is FIG. (6) which shows a nomograph of a power split device. FIG. 2 is a diagram (part 2) illustrating a hybrid system and an automatic transmission. It is a figure (the 2) which shows an operation | movement table | surface. It is a figure (the 2) which shows a shift map.

Explanation of symbols

  100 hybrid system, 200 engine, 310 power split mechanism, 311 1st MG, 312 2nd MG, 320 planetary gear, 322 sun gear, 324 pinion gear, 326 carrier, 328 ring gear, 400 automatic transmission, 500 propeller shaft, 600 differential gear, 700 rear wheel , 800 ECU, 802 ROM, 804 shift lever, 806 position switch, 808 accelerator pedal, 810 accelerator opening sensor, 812 brake pedal, 814 pedal force sensor, 816 electronic throttle valve, 818 throttle opening sensor, 820 engine speed sensor, 822 input shaft rotational speed sensor, 824 output shaft rotational speed sensor, 840 shift operation determination unit, 842 engagement unit, 844 start determination unit, 846 control unit, 848 engine speed determination unit, 850 ignition start unit.

Claims (8)

A differential mechanism having a first rotating element, a second rotating element, and a third rotating element, wherein the rotating speed of the other rotating element changes according to the rotating speed of any one rotating element; A rotating electrical machine coupled to one rotating element, a state coupled to the second rotating element, and a state in which torque input from the second rotating element is transmitted to a wheel, and from the second rotating element to the wheel A control apparatus for a power train, comprising: a switching mechanism capable of switching a state of interrupting transmission of torque; and an engine coupled to the third rotating element,
When a shift operation from the non-travel position to the travel position is performed, the state where the transmission of torque from the second rotating element to the wheel is cut off is switched to the state where torque is transmitted to the wheel. Means for controlling the switching mechanism;
A determination means for determining whether or not to start the engine when a shift operation from the non-travel position to the travel position is performed;
When it is determined that the engine is to be started, the output shaft rotational speed of the engine is changed during switching from a state in which transmission of torque from the second rotation element to the wheel is interrupted to a state in which torque is transmitted to the wheel. And a control means for controlling the engine so as to start ignition in the engine when it becomes larger than a threshold value.   The controller controls the rotating electric machine so that a force acts on the third rotating element in the same direction as the rotating direction of the third rotating element during operation of the engine before starting ignition in the engine. The power train control device according to claim 1, further comprising means for controlling the power train. The first rotating element is a sun gear;
The second rotating element is a ring gear;
The power train control device according to claim 1 or 2, wherein the third rotating element is a carrier that rotatably supports a pinion gear that meshes with the sun gear and the ring gear. A differential mechanism having a first rotating element, a second rotating element, and a third rotating element, wherein the rotating speed of the other rotating element changes according to the rotating speed of any one rotating element; A rotating electrical machine coupled to one rotating element, a state coupled to the second rotating element, and a state in which torque input from the second rotating element is transmitted to a wheel, and from the second rotating element to the wheel A control method of a power train comprising a switching mechanism capable of switching a state of interrupting transmission of torque and an engine coupled to the third rotating element,
When a shift operation from the non-travel position to the travel position is performed, the state where the transmission of torque from the second rotating element to the wheel is cut off is switched to the state where torque is transmitted to the wheel. Controlling the switching mechanism;
Determining whether to start the engine when a shift operation from the non-travel position to the travel position is performed;
When it is determined that the engine is to be started, the output shaft rotational speed of the engine is changed during switching from a state in which transmission of torque from the second rotation element to the wheel is interrupted to a state in which torque is transmitted to the wheel. Controlling the engine to start ignition in the engine when greater than a threshold value.   In the control method, before starting ignition in the engine, the rotating electric machine is configured such that a force acts on the third rotating element in the same direction as the rotating direction of the third rotating element during operation of the engine. The power train control method according to claim 4, further comprising a step of controlling the power train. The first rotating element is a sun gear;
The second rotating element is a ring gear;
6. The power train control method according to claim 4, wherein the third rotating element is a carrier that rotatably supports a pinion gear that meshes with the sun gear and the ring gear. 7.   The program which makes a computer implement | achieve the control method in any one of Claims 4-6.   A computer-readable recording medium recording a program for causing a computer to implement the control method according to claim 4.

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