JP2010208362A - Hybrid vehicle and control method for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To further properly start an internal combustion engine by motoring in backward driving. <P>SOLUTION: When an accelerator opening Acc is less than an opening threshold Aref, a torque corresponding to a requested torque Tr* is output from a second motor while stopping operation control of an engine (S150-S170). When the accelerator opening Acc is the opening threshold Aref or more, or the requested torque Tr* cannot be output even when a rated torque Tm2min is output from the second motor, the second motor is used without starting the engine by motoring when the vehicle cannot backs up or the requested torque Tr* cannot be output to a ring gear shaft as a drive shaft even when the engine is started by motoring (S180-S260). If this is not the case, the engine is started by motoring so that the requested torque Tr* is output to the ring gear shaft 32a (S270, S280). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a hybrid vehicle and a control method thereof.

  Conventionally, this type of hybrid vehicle includes an engine, a first motor, a drive shaft coupled to drive wheels, a planetary gear mechanism in which the engine and the first motor are connected to a ring gear, a carrier, and a sun gear, It has been proposed that a second motor connected to the shaft, a battery electrically connected to the first motor and the second motor, and to travel with the motoring of the engine when traveling backward ( For example, see Patent Document 1). In this hybrid vehicle, the motor can be motored when the required torque exceeds the rated maximum torque of the second motor during reverse travel, so that the reverse travel can be performed with a torque larger than the torque that can be output from the second motor. It is supposed to be possible.

JP 2007-112291 A

  In the hybrid vehicle described above, when the engine is motored when the required torque exceeds the rated maximum torque of the second motor during reverse travel, the torque output to the drive shaft does not increase smoothly, and the driver or passenger May give a sense of incongruity. Further, when the torque from the second motor is limited, the required torque can be output even if the engine is motored on condition that the required torque exceeds the rated maximum torque of the second motor when traveling backward. There are cases where it is not possible. Furthermore, when the slope is large on the uphill road in the reverse direction, even if the engine is motored, it may not be possible to climb up just because the drivability is impaired.

  The main object of the hybrid vehicle and its control method of the present invention is to perform motoring of the internal combustion engine more appropriately when traveling backward.

  The hybrid vehicle of the present invention and its control method employ the following means in order to achieve the main object described above.

The hybrid vehicle of the present invention
The internal drive engine, a first electric motor capable of inputting / outputting power, a drive shaft connected to drive wheels, an output shaft of the internal combustion engine, and a rotation shaft of the first electric motor on the collinear diagram, the drive A planetary gear mechanism in which three rotating elements are connected so as to be arranged in the order of the shaft, the output shaft, and the rotating shaft; a second motor capable of inputting / outputting power to / from the driving shaft; the first motor and the second motor And a power storage means capable of exchanging electric power,
Requested driving force setting means for setting a requested driving force required for traveling based on the accelerator operation amount;
When the shift position is a reverse travel position and the accelerator operation amount is less than a predetermined operation amount, the internal combustion engine, the first motor, and the vehicle are driven so as to travel based on the set required driving force with the internal combustion engine stopped. The second electric motor is controlled so that when the shift position is a reverse drive position and the accelerator operation amount is equal to or greater than the predetermined operation amount, the vehicle travels based on the set required driving force with motoring of the internal combustion engine. Control means for controlling the internal combustion engine, the first electric motor, and the second electric motor;
It is a summary to provide.

  In the hybrid vehicle according to the present invention, when the shift position is a reverse travel position and the accelerator operation amount is less than the predetermined operation amount, the internal combustion engine is stopped and the required driving force required for traveling based on the accelerator operation amount is determined. The internal combustion engine, the first electric motor, and the second electric motor are controlled so as to travel, and when the shift position is a reverse travel position and the accelerator operation amount is greater than or equal to a predetermined operation amount, the internal combustion engine is motored and based on the required driving force The internal combustion engine, the first electric motor, and the second electric motor are controlled so that the vehicle travels. As a result, the motoring of the internal combustion engine can be performed more appropriately when traveling backward. In this case, the predetermined operation amount may be an operation amount slightly smaller than the maximum accelerator operation amount. In this way, it is possible to smoothly increase the driving force output to the drive shaft as compared with the motoring of the internal combustion engine when the accelerator operation amount is the maximum accelerator operation amount.

  In such a hybrid vehicle of the present invention, the control means substantially stops rotation while the second electric motor outputs torque even when the shift position is a reverse travel position and the accelerator operation amount is equal to or greater than the predetermined operation amount. Then, when the driving force of the second electric motor is limited by entering a locked state in which a predetermined time elapses, it may be a means for controlling without performing motoring of the internal combustion engine. In this way, since it is possible to suppress motoring of the internal combustion engine in a state where the required driving force cannot be output even if motoring of the internal combustion engine is performed, unnecessary motoring of the internal combustion engine can be suppressed. it can.

  In the hybrid vehicle of the present invention, the control means may be configured such that the set required driving force is based on the road surface gradient even when the shift position is a reverse travel position and the accelerator operation amount is equal to or greater than the predetermined operation amount. When the vehicle obtained is less than the driving force necessary for climbing in the reverse direction, the vehicle can be controlled without motoring the internal combustion engine. This suppresses unnecessary motoring of the internal combustion engine because it is possible to suppress motoring of the internal combustion engine in a state where the vehicle cannot climb in the reverse direction even if motoring of the internal combustion engine is performed. Can do.

The hybrid vehicle control method of the present invention includes:
The internal drive engine, a first electric motor capable of inputting / outputting power, a drive shaft connected to drive wheels, an output shaft of the internal combustion engine, and a rotation shaft of the first electric motor on the collinear diagram, the drive A planetary gear mechanism in which three rotating elements are connected so as to be arranged in the order of the shaft, the output shaft, and the rotating shaft; a second motor capable of inputting / outputting power to / from the driving shaft; the first motor and the second motor And a storage means capable of exchanging electric power, and a hybrid vehicle control method comprising:
When the shift position is a reverse travel position and the accelerator operation amount is less than a predetermined operation amount, the internal combustion engine is configured to travel based on a required driving force required for travel based on the accelerator operation amount while the internal combustion engine is stopped. When the shift position is a position for reverse travel and the accelerator operation amount is greater than or equal to the predetermined operation amount, the set required driving force accompanying motoring of the internal combustion engine is controlled by controlling the first motor and the second motor. Controlling the internal combustion engine, the first electric motor and the second electric motor so as to travel based on
It is characterized by that.

  In this hybrid vehicle control method of the present invention, when the shift position is a reverse drive position and the accelerator operation amount is less than a predetermined operation amount, the required driving force required for traveling based on the accelerator operation amount with the internal combustion engine stopped. The internal combustion engine, the first electric motor, and the second electric motor are controlled so as to travel based on the engine, and when the shift position is a reverse traveling position and the accelerator operation amount is equal to or greater than a predetermined operation amount, the required drive is accompanied by motoring of the internal combustion engine. The internal combustion engine, the first electric motor, and the second electric motor are controlled to travel based on the force. As a result, the motoring of the internal combustion engine can be performed more appropriately when traveling backward. In this case, the predetermined operation amount may be an operation amount slightly smaller than the maximum accelerator operation amount. In this way, it is possible to smoothly increase the driving force output to the drive shaft as compared with the motoring of the internal combustion engine when the accelerator operation amount is equal to or greater than the maximum accelerator operation amount.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 as an embodiment of the present invention. It is a flowchart which shows an example of the reverse drive control routine performed by the hybrid electronic control unit of the embodiment. It is explanatory drawing which shows an example of the map for request | requirement torque setting. It is explanatory drawing which shows an example of the map for temporary opening threshold value setting. It is explanatory drawing which shows an example of the collinear diagram which shows the dynamic relationship between the rotation speed and torque in the rotation element of the power distribution integration mechanism 30 at the time of reverse drive using only the motive power from motor MG2. An example of a collinear diagram showing a dynamic relationship between the rotational speed and torque in the rotating elements of the power distribution and integration mechanism 30 when the vehicle 22 is traveling backward using the power from the motor MG2 with motoring of the engine 22. It is explanatory drawing shown. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 120 according to a modification.

  Next, the form for implementing this invention is demonstrated using an Example.

  FIG. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as an embodiment of the present invention. As shown in the figure, the hybrid vehicle 20 of the embodiment includes an engine 22, a three-shaft power distribution / integration mechanism 30 connected to a crankshaft 26 as an output shaft of the engine 22 via a damper 28, and power distribution / integration. A motor MG1 capable of generating electricity connected to the mechanism 30, a reduction gear 35 attached to a ring gear shaft 32a as a drive shaft connected to the power distribution and integration mechanism 30, a motor MG2 connected to the reduction gear 35, And a hybrid electronic control unit 70 for controlling the entire power output apparatus.

  The engine 22 is an internal combustion engine that outputs power using a hydrocarbon-based fuel such as gasoline or light oil, and an engine electronic control unit (hereinafter referred to as an engine ECU) that receives signals from various sensors that detect the operating state of the engine 22. ) 24 is subjected to operation control such as fuel injection control, ignition control, intake air amount adjustment control and the like. The engine ECU 24 is in communication with the hybrid electronic control unit 70, controls the operation of the engine 22 by a control signal from the hybrid electronic control unit 70, and, if necessary, transmits data related to the operating state of the engine 22 to the hybrid electronic control. Output to unit 70. The engine ECU 24 also calculates the rotational speed of the crankshaft 26, that is, the rotational speed Ne of the engine 22 based on a signal from a crank position sensor (not shown) attached to the crankshaft 26.

  The power distribution and integration mechanism 30 includes an external gear sun gear 31, an internal gear ring gear 32 arranged concentrically with the sun gear 31, a plurality of pinion gears 33 that mesh with the sun gear 31 and mesh with the ring gear 32, A planetary gear mechanism is provided that includes a carrier 34 that holds a plurality of pinion gears 33 so as to rotate and revolve, and that performs differential action using the sun gear 31, the ring gear 32, and the carrier 34 as rotational elements. In the power distribution and integration mechanism 30, the crankshaft 26 of the engine 22 is connected to the carrier 34, the motor MG1 is connected to the sun gear 31, and the reduction gear 35 is connected to the ring gear 32 via the ring gear shaft 32a. When functioning as a generator, power from the engine 22 input from the carrier 34 is distributed according to the gear ratio between the sun gear 31 side and the ring gear 32 side, and when the motor MG1 functions as an electric motor, the engine input from the carrier 34 The power from 22 and the power from the motor MG1 input from the sun gear 31 are integrated and output to the ring gear 32 side. The power output to the ring gear 32 is finally output from the ring gear shaft 32a to the drive wheels 63a and 63b of the vehicle via the gear mechanism 60 and the differential gear 62.

  The motor MG1 and the motor MG2 are both configured as well-known synchronous generator motors that can be driven as generators and can be driven as motors, and exchange power with the battery 50 via inverters 41 and 42. The power line 54 connecting the inverters 41 and 42 and the battery 50 is configured as a positive electrode bus and a negative electrode bus shared by the inverters 41 and 42, and the electric power generated by one of the motors MG1 and MG2 It can be consumed by a motor. Therefore, battery 50 is charged / discharged by electric power generated from one of motors MG1 and MG2 or insufficient electric power. If the balance of electric power is balanced by the motors MG1 and MG2, the battery 50 is not charged / discharged. The motors MG1 and MG2 are both driven and controlled by a motor electronic control unit (hereinafter referred to as a motor ECU) 40. The motor ECU 40 detects signals necessary for driving and controlling the motors MG1 and MG2, such as signals from rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2, and current sensors (not shown). The phase current applied to the motors MG1 and MG2 to be applied is input, and a switching control signal to the inverters 41 and 42 is output from the motor ECU 40. The motor ECU 40 is in communication with the hybrid electronic control unit 70, controls the driving of the motors MG1 and MG2 by a control signal from the hybrid electronic control unit 70, and, if necessary, data on the operating state of the motors MG1 and MG2. Output to the hybrid electronic control unit 70. The motor ECU 40 also calculates the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 based on signals from the rotational position detection sensors 43 and 44.

  The battery 50 is managed by a battery electronic control unit (hereinafter referred to as a battery ECU) 52. The battery ECU 52 receives signals necessary for managing the battery 50, for example, a voltage between terminals from a voltage sensor (not shown) installed between terminals of the battery 50, and a power line 54 connected to the output terminal of the battery 50. The charging / discharging current from the attached current sensor (not shown), the battery temperature Tb from the temperature sensor 51 attached to the battery 50, and the like are input. Output to the control unit 70. Further, the battery ECU 52 calculates the remaining capacity (SOC) based on the integrated value of the charging / discharging current detected by the current sensor in order to manage the battery 50, and calculates the remaining capacity (SOC) and the battery temperature Tb. The input / output limits Win and Wout, which are the maximum allowable power that may charge / discharge the battery 50, are calculated based on the above. The input / output limits Win and Wout of the battery 50 are set to the basic values of the input / output limits Win and Wout based on the battery temperature Tb, and the output limiting correction coefficient and the input are set based on the remaining capacity (SOC) of the battery 50. It can be set by setting a correction coefficient for restriction and multiplying the basic value of the set input / output restrictions Win and Wout by the correction coefficient.

  The hybrid electronic control unit 70 is configured as a microprocessor centered on the CPU 72, and in addition to the CPU 72, a ROM 74 for storing processing programs, a RAM 76 for temporarily storing data, an input / output port and communication not shown. And a port. The hybrid electronic control unit 70 includes an ignition signal from an ignition switch 80, a shift position SP from a shift position sensor 82 that detects the operation position of the shift lever 81, and an accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. The accelerator opening Acc from the vehicle, the brake pedal position BP from the brake pedal position sensor 86 that detects the amount of depression of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 88, the gradient θ from the gradient sensor 89 that detects the road surface gradient, etc. Is input via the input port. As described above, the hybrid electronic control unit 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52. ing. Note that the shift position SP of the shift lever 81 includes a normal forward drive position (D position), a reverse drive reverse position (R position), a parking position (P position) used during parking, and a neutral neutral position. (N position).

  The hybrid vehicle 20 of the embodiment thus configured calculates the required torque to be output to the ring gear shaft 32a as the drive shaft based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal 83 by the driver. Then, the operation of the engine 22, the motor MG1, and the motor MG2 is controlled so that the required power corresponding to the required torque is output to the ring gear shaft 32a. As operation control of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is controlled so that power corresponding to the required power is output from the engine 22, and all of the power output from the engine 22 is the power distribution and integration mechanism 30. Torque conversion operation mode for driving and controlling the motor MG1 and the motor MG2 so that the torque is converted by the motor MG1 and the motor MG2 and output to the ring gear shaft 32a, and the required power and the power required for charging and discharging the battery 50. The engine 22 is operated and controlled so that suitable power is output from the engine 22, and all or part of the power output from the engine 22 with charging / discharging of the battery 50 is the power distribution and integration mechanism 30, the motor MG1, and the motor. The required power is converted to the ring gear shaft 32 with torque conversion by MG2. Charge / discharge operation mode in which the motor MG1 and the motor MG2 are driven and controlled so as to be output to each other, and a motor operation mode in which the operation of the engine 22 is stopped and the power corresponding to the required power from the motor MG2 is output to the ring gear shaft 32a. and so on.

  Next, the operation of the hybrid vehicle 20 of the embodiment configured as described above, particularly the operation when traveling backward is described. FIG. 2 is a flowchart showing an example of a reverse drive control routine executed by the hybrid electronic control unit 70. This routine is repeatedly executed every predetermined time (for example, every several msec) when the shift position SP is the reverse position (R position).

  When the reverse drive control routine is executed, the CPU 72 of the hybrid electronic control unit 70 first starts the accelerator opening Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 88, and the gradient θ from the gradient sensor 89. Then, a process of inputting data necessary for control such as the rotational speed Nm2 of the motor MG2 is executed (step S100). Here, the rotational speed Nm2 of the motor MG2 is calculated from the rotational position of the rotor of the motor MG2 detected by the rotational position detection sensor 44 and is input from the motor ECU 40 by communication. In the embodiment, the vehicle speed V and the rotational speed Nm2 are negative values when the vehicle is going backward, and the gradient θ is positive values when the vehicle is going uphill in the backward direction.

  When the data is thus input, the required torque Tr * to be output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 63a and 63b as the torque required for the vehicle based on the input accelerator opening Acc and the vehicle speed V. Is set (step S110), and a climbing request torque Tra as a torque necessary for the vehicle to climb in the reverse direction is set based on the input gradient θ (step S120). In the embodiment, the required torque Tr * is determined in advance by storing the relationship between the accelerator opening Acc, the vehicle speed V, and the required torque Tr * in the ROM 74 as a required torque setting map, and the accelerator opening Acc, the vehicle speed V, , The corresponding required torque Tr * is derived and set from the stored map. FIG. 3 shows an example of the required torque setting map. Further, in the formula (1), a ring gear shaft 32a having a force acting on the vehicle as a drive shaft with respect to the product of the vehicle mass M (for example, when the vehicle is seated) M, the gravitational acceleration g, and the sine value of the gradient θ. The uphill request torque Tra (positive value in the embodiment) is calculated by multiplying the conversion factor ka by which the torque acting on is converted.

  Tra = M ・ g ・ sinθ ・ ka (1)

  Subsequently, as the accelerator opening Acc when the product of the required torque Tr * and the rated torque Tm2min (negative value in the embodiment) of the motor MG2 and the gear ratio Gr of the reduction gear 35 becomes equal to the input vehicle speed V. Is set (step S130), and a value obtained by subtracting the predetermined opening ΔA from the set temporary opening threshold Atmp is set as the opening threshold Aref (step S140), and the input accelerator opening Acc is set. Is compared with the set opening threshold Aref (step S150). In the embodiment, the temporary opening threshold value Atmp is a map in which the relationship between the vehicle speed V and the temporary opening threshold value Atmp is determined in advance and stored in the ROM 74 as a temporary opening threshold setting map, and stored when the vehicle speed V is given. The corresponding temporary opening threshold value Atmp is derived and set from the above. FIG. 4 shows an example of the temporary opening threshold value setting map. Here, in order to explain the opening degree threshold Aref and the predetermined opening degree ΔA, the rotational speed and torque in the rotating elements of the power distribution and integration mechanism 30 when the vehicle travels backward using only the power from the motor MG2. An example of a collinear diagram showing a dynamic relationship is shown in FIG. 5, and the rotation in the rotating element of the power distribution and integration mechanism 30 when the vehicle 22 is traveling backward using the power from the motor MG2 with the motoring of the engine 22. An example of a collinear diagram showing the dynamic relationship between the number and the torque is shown in FIG. 5 and 6, the left S-axis indicates the rotation speed of the sun gear 31 that is the rotation speed Nm1 of the motor MG1, the C-axis indicates the rotation speed of the carrier 34 that is the rotation speed Ne of the engine 22, and the R-axis is The rotational speed Nr of the ring gear 32 obtained by dividing the rotational speed Nm2 of the motor MG2 by the gear ratio Gr of the reduction gear 35 is shown. In FIG. 6, the two thick arrows on the R axis indicate the torque acting on the ring gear shaft 32a by the torque Tm1 from the motor MG1 motoring the engine 22 that has stopped fuel injection, and the torque Tm2 output from the motor MG2. The torque acting on the ring gear shaft 32a via the reduction gear 35 is shown. As shown in FIG. 5, when the vehicle travels backward only by the power from the motor MG2, the accelerator pedal 83 is greatly depressed, and the required torque Tr * becomes smaller than the product of the rated torque Tm2min of the motor MG2 and the gear ratio Gr ( When the absolute value is large), only the torque insufficient for the required torque Tr * can be output to the ring gear shaft 32a as the drive shaft. For this reason, in the embodiment, by starting motoring of the engine 22 before the required torque Tr * based on the accelerator opening Acc exceeds the product of the rated torque Tm2min and the gear ratio Gr, as shown in FIG. In addition, a torque larger in absolute value than the product of the rated torque Tm2min from the motor MG2 and the gear ratio Gr is applied to the ring gear shaft 32a. Therefore, when the driver does not start motoring of the engine 22 when the driver depresses the accelerator pedal 83, the opening threshold value Aref is the required torque Tr * for the ring gear shaft 32a even if the rated torque Tm2min is output from the motor MG2. It is for judging that it will be in the state which cannot output. Further, the predetermined opening degree ΔA is determined after the accelerator opening degree Acc reaches the temporary opening degree threshold value Atmp, that is, after the engine is in a state of outputting the minimum (maximum absolute value) rated torque Tm2min that can be output from the motor MG2. When motoring No. 22 is started, the torque output to the ring gear shaft 32a fluctuates and a shock occurs, which may impair drivability (which may cause the driver and passengers to feel uncomfortable). It was. That is, the predetermined opening degree ΔA is an accelerator opening degree that can prevent the drivability from being impaired in order to secure a time during which the torque increase from the motor MG2 and the torque output by the motoring of the engine 22 occur simultaneously. This is for starting motoring of the engine 22 at a timing earlier than Acc reaches the provisional opening threshold value Atmp. In the embodiment, a small value (experimentally determined based on the characteristics of the motor MG1 and the like) For example, 3%, 5%, 10%, etc.) were used.

  When the accelerator opening Acc is less than the opening threshold Aref, it is determined that the motoring of the engine 22 is not performed, a value 0 is set in the torque command Tm1 * of the motor MG1 (step S160), and the required torque Tr * is decelerated. A value obtained by dividing by the gear ratio Gr of the gear 35 is set as a torque command Tm2 * of the motor MG2 (step S170), and the set torque commands Tm1 * and Tm2 * are transmitted to the motor ECU 40 (step S290) to drive at the time of reverse travel. The control routine ends. Receiving the torque commands Tm1 * and Tm2 *, the motor ECU 40 controls the switching elements of the inverters 41 and 42 so that the motor MG1 is driven by the torque command Tm1 * and the motor MG2 is driven by the torque command Tm2 *. . Note that operation control such as fuel injection control, ignition control, and intake air amount adjustment control of the engine 22 by the engine ECU 24 is stopped unless the motor 22 is motored. By such control, when the accelerator opening Acc is less than the opening threshold Aref, the required torque Tr * can be output from the motor MG2 to the ring gear shaft 32a as the drive shaft, and the vehicle can travel backward.

  When the accelerator opening Acc is equal to or greater than the opening threshold Aref, it is determined whether or not the absolute value of the required torque Tr * is greater than the requested climbing torque Tra (step S180), and the absolute value of the requested torque Tr * is determined as the requested climbing torque Tra. In the following cases, it is determined that there is a high possibility that the vehicle cannot climb in the reverse direction even if motoring of the engine 22 is performed, and a value 0 is set to the torque command Tm1 * of the motor MG1 (step S190). The greater of the required torque Tr * divided by the gear ratio Gr of the reduction gear 35 and the rated torque Tm2min of the motor MG2 (the smaller absolute value) is the torque command Tm2 * of the motor MG2 by the following equation (2). (Step S200), and the set torque commands Tm1 * and Tm2 * are transmitted to the motor ECU 40 (step S200). S290), to terminate the reverse drive control routine. By such control, when the accelerator opening Acc is equal to or larger than the opening threshold Aref, the motoring of the engine 22 is suppressed in a state where the vehicle cannot climb in the reverse direction even if the motoring of the engine 22 is performed. Therefore, unnecessary motoring of the engine 22 can be suppressed.

  Tm2 * = max (Tr * / Gr, Tm2min) (2)

  When the accelerator opening Acc is equal to or greater than the opening threshold Aref and the absolute value of the required torque Tr * is greater than the uphill required torque Tra, it is determined whether or not the torque is limited by the motor MG2 being locked. (Steps S210 to S230). Specifically, the absolute value of the torque command Tm2 * (previous Tm2 *) of the motor MG2 set when the routine was executed last time as representing the torque output from the motor MG2 is equal to or greater than the predetermined torque Tm2ref. (Step S210) and when the absolute value of the rotational speed Nm2 of the motor MG2 becomes less than a predetermined rotational speed Nref indicating a state in which the motor MG2 is substantially stopped (Step S220), when a predetermined time tref has elapsed. (Step S230), it is determined that the motor MG2 is in a locked state, and a value obtained by multiplying the rated torque Tm2min of the motor MG2 by a positive coefficient km less than 1 is set as the torque limit Tm2lim of the motor MG2 (Step S240). ). Here, in the embodiment, the predetermined torque Tm2ref, the predetermined rotation speed Nref, and the predetermined time tref all have a possibility that current concentrates on one phase of the three-phase coil of the motor MG2 and the motor MG2 and the inverter 42 are overheated. As the predetermined torque Tm2ref, for example, a torque corresponding to the required torque Tr * when the vehicle speed V is 0 and the accelerator opening degree Acc is 10% or 15%, or a predetermined rotational speed is used. As Nref, for example, 100 rpm or 120 rpm can be used, and as the predetermined time tref, for example, 500 msec, 600 msec, or the like can be used. Further, in the embodiment, the coefficient km is a ratio of the torque that is allowed to be output from the motor MG2 out of the rated torque Tm2min of the motor MG2, and is a value that is small enough to suppress overheating of the motor MG2 and the inverter 42 (for example, , 0.2, 0.3, 0.5, etc.).

  When the torque limit Tm2lim of the motor MG2 is set in this way, the torque command Tm1 * of the motor MG1 is set to a value 0 (step S250), and the torque set as the required torque Tr * divided by the gear ratio Gr of the reduction gear 35 is set. The larger one of the limits Tm2lim (smaller absolute value) is set as the torque command Tm2 * of the motor MG2 by the following equation (3) (step S260), and the set torque commands Tm1 * and Tm2 * are sent to the motor ECU 40. (Step S290), and the reverse drive control routine is terminated. With this control, when the accelerator opening Acc is equal to or greater than the opening threshold Aref, the required torque Tr * is output to the ring gear shaft 32a even if the engine 22 is motored to limit the torque due to the locked state of the motor MG2. Since the motoring of the engine 22 is suppressed in a state in which the engine 22 cannot be operated, it is possible to suppress the drivability from being impaired by the torque acting on the ring gear shaft 32a accompanying the motoring of the engine 22 and Unnecessary motoring can be suppressed.

  Tm2 * = max (Tr * / Gr, Tm2lim) (3)

  When the motor MG2 is not in the locked state, that is, whether the absolute value of the previous Tm2 * is less than the predetermined torque Tm2ref (step S210), or whether the absolute value of the rotational speed Nm2 is greater than or equal to the predetermined rotational speed Nref (step S220). ) Even if the absolute value of the previous Tm2 * is greater than or equal to the predetermined torque Tm2ref and the absolute value of the rotational speed Nm2 is less than the predetermined rotational speed Nref, the predetermined time period tref has not elapsed since that state was reached. (Step S230), it is determined that it is not necessary to set the torque limit Tm2lim of the motor MG2 and motoring of the engine 22 is performed, and the required torque Tr * is divided by the gear ratio Gr of the reduction gear 35. Of the motor and the rated torque Tm2min of the motor MG2 is the larger one (the smaller absolute value). The torque command Tm2 * of the motor MG2 is set according to the equation (2) (step S270), and the power distribution and integration is performed by subtracting the product of the torque command Tm2 * set from the required torque Tr * and the gear ratio Gr of the reduction gear 35. Torque command Tm1 * of motor MG1 is set by the following equation (4) that multiplies gear ratio ρ of mechanism 30 and value −1 (step S280), and the set torque commands Tm1 * and Tm2 * are transmitted to motor ECU 40. (Step S290), the reverse drive control routine is terminated. The expression (4) is obtained when the torque corresponding to the torque command Tm2 * is output from the motor MG2 to the ring gear shaft 32a as the drive shaft from the motor MG1 that motors the engine 22 to the torque that is insufficient with respect to the required torque Tr *. This is a dynamic relational expression for the rotating elements of the power distribution and integration mechanism 30 for acting, and can be easily derived from the collinear diagram of FIG. When motoring the engine 22, the engine ECU 24 controls the operation of the engine 22 so that the throttle opening becomes a predetermined opening (for example, the throttle opening during idle operation, etc.). Does not. By such control, when the accelerator opening Acc is equal to or larger than the opening threshold Aref, even if motoring of the engine 22 is performed, the motor 22 can be motored in a state where the vehicle cannot climb in the reverse direction. By suppressing the motoring of the engine 22 in a state where the required torque Tr * cannot be output to the ring gear shaft 32a due to the torque limitation of the motor MG2 even if motoring is performed, an unnecessary motor of the engine 22 is suppressed. The engine 22 is motored so that the required torque Tr * is output when the required torque Tr * cannot be output even when the rated torque Tm2min is output from the motor MG2. So, when you drive backwards, the engine It can be carried out 2 motoring more properly. Moreover, the opening degree threshold value Aref to be compared with the accelerator opening degree Acc is assumed to be a temporary opening degree Acc when the product of the required torque Tr * and the rated torque Tm2min of the motor MG2 and the gear ratio Gr is equal to the vehicle speed V. Since the predetermined opening degree ΔA is smaller than the opening degree threshold value Atmp, it is possible to prevent the drivability from being impaired when the motoring of the engine 22 is started. Of course, when the accelerator opening degree Acc is less than the opening degree threshold value Aref, the motor MG2 can output the required torque Tr * to the ring gear shaft 32a as the drive shaft to travel backward.

  Tm1 * =-ρ ・ (Tr * -Tm2 * ・ Gr) (4)

  According to the hybrid vehicle 20 of the embodiment described above, when the accelerator opening Acc is less than the opening threshold Aref, a torque corresponding to the required torque Tr * is output from the motor MG2 while the operation control of the engine 22 is stopped. When the accelerator opening degree Acc is equal to or larger than the opening degree threshold value Aref, even if motoring of the engine 22 is performed, the motoring of the engine 22 is performed in a state where the vehicle cannot climb in the reverse direction. By suppressing the motoring of the engine 22 in a state where the required torque Tr * cannot be output to the ring gear shaft 32a due to the torque limitation of the motor MG2 even if motoring is performed, an unnecessary motor of the engine 22 is suppressed. The ring can be suppressed and rated from the motor MG2. The motor 22 is motored so that the required torque Tr * is output when the required torque Tr * cannot be output even when the torque Tm2min is output. Can be done.

  In the hybrid vehicle 20 of the embodiment, the engine 22 is motored depending on whether the accelerator opening Acc is equal to or larger than the opening threshold Aref that is smaller than the temporary opening threshold Atmp by the predetermined opening ΔA. Instead of the threshold value Aref, motoring of the engine 22 may be performed depending on whether or not the accelerator opening degree Acc is greater than or equal to the opening degree threshold value Aref2 as a predetermined value (for example, 80%, 90%, 100%, etc.). . In this case, instead of whether or not the accelerator opening Acc is greater than or equal to the opening threshold Aref2, the accelerator opening Acc is greater than or equal to the opening threshold Aref2 and the absolute value of the rotational speed Nm2 of the motor MG2 is less than the predetermined rotational speed Nref. Then, the motoring of the engine 22 may be performed depending on whether or not a predetermined time tref2 shorter than the predetermined time tref has elapsed. In this way, it is possible to make it easier to get over a step on a flat road before the motor MG2 is locked.

  In the hybrid vehicle 20 of the embodiment, the motoring of the engine 22 is not performed when the absolute value of the required torque Tr * is equal to or less than the climbing required torque Tra. However, even when the accelerator opening Acc is equal to or larger than the opening threshold Aref. For example, the motoring of the engine 22 may be performed regardless of whether or not the absolute value of the required torque Tr * is equal to or less than the uphill required torque Tra.

  In the hybrid vehicle 20 of the embodiment, the motor 22 is not motored when the torque limit Tm2lim of the motor MG2 is set by the motor MG2 being locked, but the accelerator opening Acc is the opening threshold Aref. At the above time, the motor 22 may be motored regardless of whether or not the motor MG2 is in the locked state.

  In the hybrid vehicle 20 of the embodiment, the motor opening of the engine 22 is performed or not performed depending on whether or not the accelerator opening Acc is equal to or larger than the opening threshold Aref. Instead of the above, the motor of the engine 22 depends on whether the required torque Tr * is less than or equal to the product of the rated torque Tm2min of the motor MG2 and the gear ratio Gr of the reduction gear 35 (absolute value is more than this product). The ring may or may not be ringed.

  In the hybrid vehicle 20 of the embodiment, the climbing required torque Tra is set by the equation (1) based on the gradient θ, but based on the value obtained by the equation (1) based on the gradient θ and the wheel rolling resistance. The sum of the torque (for example, the product of the vehicle mass M, the gravitational acceleration g, and the rolling resistance coefficient kr multiplied by the conversion coefficient ka described above) may be set as the uphill request torque Tra. .

  In the hybrid vehicle 20 of the embodiment, the power of the motor MG2 is shifted by the reduction gear 35 and output to the ring gear shaft 32a. However, as illustrated in the hybrid vehicle 120 of the modified example of FIG. May be output to an axle (an axle connected to the wheels 64a and 64b in FIG. 7) different from an axle to which the ring gear shaft 32a is connected (an axle to which the drive wheels 63a and 63b are connected).

  Moreover, it is not limited to what is applied to such a hybrid vehicle, It is good also as forms of hybrid vehicles, such as a train other than a vehicle. Moreover, it is good also as a form of the control method of such a hybrid vehicle.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the engine 22 corresponds to an “internal combustion engine”, the motor MG1 corresponds to a “first electric motor”, the power distribution integration mechanism 30 corresponds to a “planetary gear mechanism”, and the motor MG2 corresponds to a “second electric motor”. 2 in which the battery 50 corresponds to “power storage means” and the required torque Tr * is set based on the accelerator opening Acc and the vehicle speed V. The electronic control unit 70 corresponds to “required driving force setting means”, and when the accelerator opening Acc is less than the opening threshold Aref, the torque corresponding to the required torque Tr * is output from the motor MG2 while the operation control of the engine 22 is stopped. Is set to the torque command Tm1 * so that the vehicle travels, and the torque command Tm2 * based on the required torque Tr * is set, and the accelerator opening A When c is equal to or larger than the opening threshold value Aref, unnecessary motoring of the engine 22 is suppressed, and the torque command Tm1 * of the motor MG1 and the torque command Tm2 of the motor MG2 are based on the required torque Tr * and the rated torque Tm2min. The torque control Tm1 * and Tm2 * set by setting * are transmitted to the motor ECU 40, and the operation of the hybrid electronic control unit 70 and the engine 22 for executing the processing of steps S120 to S290 of the reverse drive control routine of FIG. The engine ECU 24 that stops control and adjusts the throttle opening and the motor ECU 40 that controls the inverters 41 and 42 so that the motors MG1 and MG2 are driven by the torque commands Tm1 * and Tm2 * correspond to “control means”. To do.

  Here, the “internal combustion engine” is not limited to an internal combustion engine that outputs power using a hydrocarbon fuel such as gasoline or light oil, and may be any type of internal combustion engine such as a hydrogen engine. The “first motor” is not limited to the motor MG1 configured as a synchronous generator motor, and may be any type of motor such as an induction motor that can input and output power. The “planetary gear mechanism” is not limited to the power distribution and integration mechanism 30 described above, but is connected to four or more shafts by using a double pinion type planetary gear mechanism or a combination of a plurality of planetary gear mechanisms. Three rotating elements, such as a driving shaft, an output shaft of the internal combustion engine, and a rotating shaft of the first motor, are arranged in the order of the driving shaft, the output shaft, and the rotating shaft on the collinear diagram. Any device can be used as long as it is connected. The “second electric motor” is not limited to the motor MG2 configured as a synchronous generator motor, and may be any type of electric motor such as an induction motor that can input and output power to the drive shaft. I do not care. The “storage means” is not limited to the battery 50 as a secondary battery, and may be anything as long as it can exchange power with the first motor and the second motor, such as a capacitor. The “required driving force setting means” is not limited to the one that sets the required torque Tr * based on the accelerator opening Acc and the vehicle speed V, but sets the required torque based only on the accelerator opening Acc. Any device may be used as long as the required driving force required for traveling is set based on the accelerator operation amount. The “control means” is not limited to the combination of the hybrid electronic control unit 70, the engine ECU 24, and the motor ECU 40, and may be configured by a single electronic control unit. Further, as the “control means”, when the accelerator opening Acc is less than the opening threshold Aref, the motor MG2 outputs a torque corresponding to the required torque Tr * while the operation control of the engine 22 is stopped. A value 0 is set for the command Tm1 * and a torque command Tm2 * based on the required torque Tr * is set to suppress unnecessary motoring of the engine 22 when the accelerator opening Acc is equal to or larger than the opening threshold Aref. The motors MG1, MG2 are driven by the torque commands Tm1 *, Tm2 * set by setting the torque command Tm1 * of the motor MG1 and the torque command Tm2 * of the motor MG2 based on the required torque Tr * and the rated torque Tm2min. The inverters 41 and 42 are controlled so that the operation control of the engine 22 is stopped or the throttle is opened. Is not limited to those that adjust the engine, but when the shift position is the reverse drive position and the accelerator operation amount is less than the predetermined operation amount, it is based on the required driving force set with the internal combustion engine stopped. A request set with motoring of the internal combustion engine when the internal combustion engine, the first electric motor, and the second electric motor are controlled so as to travel at the same time, and the shift operation position is a reverse travel position and the accelerator operation amount is greater than or equal to a predetermined operation amount. Any device may be used as long as it controls the internal combustion engine, the first electric motor, and the second electric motor so as to travel based on the driving force.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the column of means for solving the problem. Therefore, the elements of the invention described in the column of means for solving the problems are not limited. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description of the column, and the examples are those of the invention described in the column of means for solving the problems. It is only a specific example.

  As mentioned above, although the form for implementing this invention was demonstrated using the Example, this invention is not limited at all to such an Example, In the range which does not deviate from the summary of this invention, it is with various forms. Of course, it can be implemented.

  The present invention can be used in the manufacturing industry of hybrid vehicles.

  20,120 Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 24a CPU, 24b ROM, 24c RAM, 26 crankshaft, 28 damper, 30 power distribution integrated mechanism, 31 sun gear, 32 ring gear, 32a ring gear Shaft, 33 Pinion gear, 34 Carrier, 35 Reduction gear, 40 Motor electronic control unit (motor ECU), 41, 42 Inverter, 43, 44 Rotation position detection sensor, 50 battery, 51 Temperature sensor, 52 Battery electronic control unit ( Battery ECU), 54 power line, 60 gear mechanism, 62 differential gear, 63a, 63b driving wheel, 64a, 64b wheel, 70 electronic control unit for hybrid, 72 CPU, 74 ROM, 7 6 RAM, 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor, 88 vehicle speed sensor, 89 gradient sensor, MG1, MG2 motor.

Claims (4)

The internal drive engine, a first electric motor capable of inputting / outputting power, a drive shaft connected to drive wheels, an output shaft of the internal combustion engine, and a rotation shaft of the first electric motor on the collinear diagram, the drive A planetary gear mechanism in which three rotating elements are connected so as to be arranged in the order of the shaft, the output shaft, and the rotating shaft; a second motor capable of inputting / outputting power to / from the driving shaft; the first motor and the second motor And a power storage means capable of exchanging electric power,
Requested driving force setting means for setting a requested driving force required for traveling based on the accelerator operation amount;
When the shift position is a reverse travel position and the accelerator operation amount is less than a predetermined operation amount, the internal combustion engine, the first motor, and the vehicle are driven so as to travel based on the set required driving force with the internal combustion engine stopped. The second electric motor is controlled so that when the shift position is a reverse drive position and the accelerator operation amount is equal to or greater than the predetermined operation amount, the vehicle travels based on the set required driving force with motoring of the internal combustion engine. Control means for controlling the internal combustion engine, the first electric motor, and the second electric motor;
A hybrid car with The hybrid vehicle according to claim 1,
The control means is a lock in which a predetermined time elapses when the second electric motor substantially stops rotating while outputting torque even when the shift position is a reverse travel position and the accelerator operation amount is equal to or greater than the predetermined operation amount. When the driving force of the second electric motor is limited by being in a state, it is means for controlling without performing motoring of the internal combustion engine,
Hybrid car. A hybrid vehicle according to claim 1 or 2,
The control means allows the vehicle in which the set required driving force is obtained on the basis of the road surface slope in the reverse direction even when the shift position is a reverse drive position and the accelerator operation amount is equal to or greater than the predetermined operation amount. Means for controlling the internal combustion engine without motoring when the driving force is less than or equal to
Hybrid car. The internal drive engine, a first electric motor capable of inputting / outputting power, a drive shaft connected to drive wheels, an output shaft of the internal combustion engine, and a rotation shaft of the first electric motor on the collinear diagram, the drive A planetary gear mechanism in which three rotating elements are connected so as to be arranged in the order of the shaft, the output shaft, and the rotating shaft; a second motor capable of inputting / outputting power to / from the driving shaft; the first motor and the second motor And a storage means capable of exchanging electric power, and a hybrid vehicle control method comprising:
When the shift position is a reverse travel position and the accelerator operation amount is less than a predetermined operation amount, the internal combustion engine is configured to travel based on a required driving force required for travel based on the accelerator operation amount while the internal combustion engine is stopped. When the shift position is a position for reverse travel and the accelerator operation amount is greater than or equal to the predetermined operation amount, the set required driving force accompanying motoring of the internal combustion engine is controlled by controlling the first motor and the second motor. Controlling the internal combustion engine, the first electric motor and the second electric motor so as to travel based on
Control method of hybrid vehicle.

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