JP2016060319A - Hybrid automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure, to some extent, time and/or distance in which a reverse travel is enabled.SOLUTION: Upper limit power Pemax of an engine is set so that a sum of required torque Tr* and torque for cancelling direct transmission torque from the engine can be output to a drive shaft from a second motor (S210-S230). If required power Pr* corresponding to the required torque Tr* is larger than the upper limit power Pemax (S240), the upper limit power Pemax is set at target power Pe* of the engine (S280), and remaining travel-enabled time Trun and remaining travel-enabled distance Lrun are calculated in accordance with a difference between the required power Pr* and the upper limit power Pemax (S300). If the remaining travel-enabled time Trun or remaining travel-enabled distance Lrun is less than each of respective thresholds, the required power Pr* is decreased (S330). Then, the engine and two motors are controlled using the required power Pr* and target power Pe*.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a hybrid vehicle. More specifically, the present invention relates to an engine, a first motor capable of inputting / outputting power, a drive shaft coupled to an axle, an output shaft of the engine, and a rotary shaft of the first motor. On the nomograph, the planetary gear connected so that the drive shaft, the output shaft, and the rotary shaft are arranged in this order, the second motor that can input and output power to the drive shaft, and the first motor and the second motor exchange power The present invention relates to a hybrid vehicle including a battery capable of being used.

  Conventionally, this type of hybrid vehicle includes an engine, a first rotating electrical machine, a first planetary mechanism in which a ring gear, a carrier, and a sun gear are connected to an axle, an output shaft of the engine, and an output shaft of the first rotating electrical machine. A second planetary mechanism in which a ring gear and a sun gear are connected to the second rotating electrical machine, the axle and the output shaft of the second rotating electrical machine and the carrier is fixed; and the first rotating electrical machine and the second rotating electrical machine When the vehicle travels backward, when the SOC value of the power storage device reaches a charge start threshold value or less, the engine is started to start forced charging by the first rotating electrical machine, and the SOC value is equal to or greater than the charge end threshold value. There has been proposed one that terminates forced charging when it reaches (for example, see Patent Document 1). In this hybrid vehicle, when the vehicle travels backward, when the gradient is equal to or greater than the gradient threshold, the charge start threshold and the charge end threshold are made smaller than when the gradient is less than the gradient threshold, thereby starting the engine. This delays the reduction in driving force on the axle caused by engine load operation, so that the target travel distance can be achieved.

JP 2010-221745 A

  In such a hybrid vehicle, when traveling backward while driving the engine under load, if the required torque (required power) in the reverse traveling direction required for the drive shaft is large, the power from the engine is used to ensure traveling performance. Using the electric power generated by the first rotating electric machine and the electric power from the power storage device, torque (power) is output from the second rotating electric machine to the drive shaft. At this time, depending on the magnitude of the discharge power from the power storage device, the SOC value of the power storage device may decrease rapidly, and the time or distance in which the reverse travel can be continued may be relatively short.

  The main purpose of the hybrid vehicle of the present invention is to secure a certain amount of time and distance in which reverse travel can be continued.

  The hybrid vehicle of the present invention employs the following means in order to achieve the main object described above.

The hybrid vehicle of the present invention
Engine,
A first motor capable of inputting and outputting power;
A drive shaft connected to an axle, an output shaft of the engine, and a rotary shaft of the first motor are connected so that three rotary elements are arranged in the order of the drive shaft, the output shaft, and the rotary shaft on a collinear diagram. Planetary gears,
A second motor capable of inputting and outputting power to the drive shaft;
A battery capable of exchanging electric power with the first motor and the second motor;
A hybrid vehicle comprising:
At a predetermined time when the engine travels backward while performing a load operation, the requested torque in the reverse travel direction required for the drive shaft and the torque in the forward travel direction that acts on the drive shaft in accordance with the load operation of the engine are canceled. The upper limit power of the engine is set so that the sum of the cancel torque and the torque can be output from the second motor to the drive shaft, and the target power of the engine is set within a range equal to or lower than the upper limit power. And setting means for controlling the engine, the first motor, and the second motor so that the target power is output from the engine and travels with the corresponding required power corresponding to the required torque,
The control means sets the upper limit power to the target power when the corresponding required power is larger than the upper limit power at the predetermined time, and travels backward according to a difference between the corresponding required power and the upper limit power. A travelable value that is at least one of a continuable time and a distance is set, and when the travelable value is equal to or greater than a threshold value, control is performed so that the vehicle travels with the corresponding required power, and when the travelable value is less than the threshold value, Control to drive with limited required power smaller than the corresponding required power,
It is characterized by that.

  In the hybrid vehicle of the present invention, at a predetermined time when the vehicle travels backward while driving the engine, the required torque in the backward travel direction required for the drive shaft and the forward travel direction that acts on the drive shaft in accordance with the load operation of the engine. The upper limit power of the engine is set so that the sum of the cancel torque for canceling the torque (direct torque) and the torque from the second motor can be output to the drive shaft. A target power is set, and the engine, the first motor, and the second motor are controlled so that the target power is output from the engine and travels with the corresponding required power corresponding to the required torque. Thereby, it can suppress that the running performance at the time of reverse running falls. And at the predetermined time, when the corresponding required power is larger than the upper limit power, the upper limit power is set to the target power, and at least one of the time and the distance at which the reverse traveling can be continued according to the difference between the corresponding required power and the upper limit power. A certain travelable value is set, and when the travelable value is equal to or greater than the threshold value, control is performed so that the vehicle travels with the corresponding travel power. To do. When the required required power is larger than the upper limit power at a predetermined time, when attempting to travel backward with the required required power, the larger the difference between the required required power and the upper limit power, the greater the discharge power from the battery, and the battery charge ratio The decrease in the speed becomes quicker and the travelable value becomes smaller. Therefore, when the travelable value is less than the threshold value, by controlling so as to travel with the limited required power, the discharge power from the battery is reduced as compared to controlling to travel with the corresponding required power, It is possible to moderate the decrease in the power storage ratio and to increase the time and distance in which the reverse travel can be continued. That is, it is possible to secure a certain amount of time and distance in which the backward traveling can be continued. Here, “corresponding required power” means power obtained by multiplying the required torque by the rotational speed of the drive shaft.

  In such a hybrid vehicle of the present invention, the control means is configured such that, at the predetermined time, when the corresponding required power is greater than the upper limit power and the travelable value is less than the threshold, the travelable value is equal to or greater than the threshold. The limit request power may be set as described above. In this way, the time and distance in which the reverse travel can be continued can be made sufficiently longer.

  In the hybrid vehicle of the present invention, the threshold value may be set such that the threshold value tends to decrease as at least one of time and distance from the start of reverse travel is longer. In this way, the threshold value can be set more appropriately.

  Further, in the hybrid vehicle of the present invention, the control means, when the corresponding required power is larger than the upper limit power at the predetermined time, calculates the difference between the storage ratio of the battery and the allowable lower limit ratio and the corresponding required power. It is also possible to calculate the time during which the reverse travel can be continued by dividing by the difference from the upper limit power, and calculate the distance at which the reverse travel can be continued as the product of the vehicle speed and the calculated time.

  In addition, in the hybrid vehicle of the present invention, when the sum of the corresponding required power and the battery charging required power is equal to or less than the upper limit power at the predetermined time, the control means includes the corresponding required power and the charging request. A power sum is set as the target power, and when the corresponding required power is equal to or lower than the upper limit power and the sum of the corresponding required power and the charging required power is larger than the upper limit power, the upper limit power is set to the target power. It can also be set to. In this way, when the sum of the corresponding required power and the required charging power of the battery is equal to or lower than the upper limit power, the vehicle can travel backward while charging the battery with the electric power corresponding to the required charging power. Also, when the corresponding required power is smaller than the upper limit power and the sum of the required required power and the required charging power is larger than the upper limit power, the vehicle travels while charging the battery with power corresponding to the difference between the upper limit power and the required required power. Can do. Further, when the corresponding required power is equal to the upper limit power and the sum of the required required power and the required charging power is larger than the upper limit power, the vehicle can travel backward without charging / discharging the battery. That is, in these cases, it is possible to travel backward while suppressing a decrease in the storage ratio of the battery.

  In the hybrid vehicle of the present invention, at the predetermined time, the control means converts the difference between the required torque and the upper limit torque in the reverse travel direction that can be output from the second motor to the drive shaft into the torque of the output shaft. The product of the upper limit torque of the engine obtained in this way and the upper limit speed of the engine can be set as the upper limit power. In this aspect of the hybrid vehicle of the present invention, the upper limit rotational speed is a first temporary upper limit rotational speed that is an upper limit rotational speed of the engine based on the performance of the planetary gear pinion gear, and the engine based on the performance of the first motor. It is also possible to set a minimum value of the second temporary upper limit rotational speed, which is the upper limit rotational speed of the engine, and the third temporary upper limit rotational speed, which is the rated value of the engine, as a lower limit guard with a value of 0. . In this way, it is possible to protect the engine, the first motor, and the pinion gear of the planetary gear.

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 predetermined time control routine performed by HVECU70 of an Example. 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 alignment chart which shows the dynamic relationship between the rotation speed and torque in the rotation element of the planetary gear 30 at the predetermined time. It is a flowchart which shows an example of an engine target driving | operation point setting process. FIG. 6 is an explanatory diagram showing an example of the relationship between the rotational speed Nr of the drive shaft 36 and the upper limit rotational speed Nemax of the engine 22. It is explanatory drawing which shows an example of the map for total target travel time setting. It is explanatory drawing which shows an example of the map for total target travel distance setting. Accelerator-corresponding required power Prac, battery 50 charging required power Pch *, engine 22 target power Pe *, actual travel power (actual Pr), and actual battery 50 It is explanatory drawing which shows an example of the relationship of charging / discharging electric power (real Pch at the time of charge, real Pdi at the time of discharge).

  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 that outputs power using gasoline, light oil, or the like as fuel, and an engine electronic control unit (hereinafter referred to as “engine ECU”) 24 that drives and controls the engine 22. A carrier 34 is connected to a crankshaft 26 as an output shaft of the engine 22 via a damper 28 and is connected to drive wheels 63a and 63b via a differential gear 62 and a gear mechanism 60. A single-pinion planetary gear 30 having a ring gear 32 connected to the drive shaft 36, a motor MG1 configured as, for example, a known synchronous generator motor and having a rotor connected to the sun gear 31 of the planetary gear 30, and a known synchronous power generation, for example. A reduction gear is configured on the drive shaft 36 as an electric motor. 5 controls the motors MG1 and MG2 by controlling the switching of the motor MG2 to which the rotor is connected via the inverter 5, the inverters 41 and 42 for driving the motors MG1 and MG2, and the switching elements of the inverters 41 and 42. A motor electronic control unit (hereinafter referred to as “motor ECU”) 40, a battery 50 configured as, for example, a lithium ion secondary battery, and exchanges power with the motors MG 1 and MG 2 via inverters 41 and 42, and a battery 50 A battery electronic control unit (hereinafter referred to as “battery ECU”) 52 to be managed and a hybrid electronic control unit (hereinafter referred to as “HVECU”) 70 for controlling the entire vehicle are provided.

  Although not shown, the engine ECU 24 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . The engine ECU 24 receives signals from various sensors necessary for controlling the operation of the engine 22 via an input port, and the engine ECU 24 outputs various control signals for controlling the operation of the engine 22. It is output through the port. The engine ECU 24 calculates the rotational speed Ne of the engine 22 based on a signal from a crank position sensor (not shown) attached to the crankshaft 26 of the engine 22.

  Although not shown, the motor ECU 40 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . The motor ECU 40 receives signals from various sensors necessary for driving and controlling the motors MG1 and MG2, for example, motors MG1 and MG1 from rotational position detection sensors 43 and 44 that detect rotational positions of the rotors of the motors MG1 and MG2. The rotational positions θm1, θm2, etc. of the rotor of MG2 are input via the input port, and the motor ECU 40 outputs a switching control signal to the switching elements (not shown) of the inverters 41, 42 via the output port. ing. The motor ECU 40 calculates the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 based on the rotational positions θm1 and θm2 of the rotors of the motors MG1 and MG2 from the rotational position detection sensors 43 and 44.

  Although not shown, the battery ECU 52 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . The battery ECU 52 is connected to signals from various sensors necessary for managing the battery 50, for example, an inter-terminal voltage Vb from a voltage sensor 51 a installed between terminals of the battery 50 and an output terminal of the battery 50. The charge / discharge current Ib from the current sensor 51b attached to the power line, the battery temperature Tb from the temperature sensor 51c attached to the battery 50, and the like are input via the input port. Further, the battery ECU 52 manages the battery 50 based on the integrated value of the charge / discharge current Ib of the battery 50 detected by the current sensor 51b with respect to the total capacity of the power that can be discharged from the battery 50 at that time. A storage ratio SOC, which is a ratio, is calculated.

  Although not shown, the HVECU 70 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. The HVECU 70 includes an ignition signal from the ignition switch 80, a shift position SP from the shift position sensor 82 that detects the operation position of the shift lever 81, and an accelerator opening from the accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. Acc, brake pedal position BP from the brake pedal position sensor 86 for detecting the depression amount of the brake pedal 85, vehicle speed V from the vehicle speed sensor 88, road surface gradient θrg from the gradient sensor 89, and the like are input via the input port. From the HVECU 70, a display control signal to the display 90 for displaying information is output via an output port. The HVECU 70 is communicably connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52. In the hybrid vehicle 20 of the embodiment, the operation position of the shift lever 81 (shift position SP detected by the shift position sensor 82) includes a parking position (P position) used during parking, and a reverse position (R for reverse travel). Position), neutral position (N position), forward drive position (D position), etc.

  The hybrid vehicle 20 of the embodiment thus configured travels in a hybrid travel mode (HV travel mode) that travels with the operation of the engine 22 or an electric travel mode (EV travel mode) that travels with the engine 22 stopped. To do.

  Next, the operation of the hybrid vehicle 20 of the embodiment configured as described above, particularly the operation at a predetermined time when the engine 22 travels backward while performing load operation will be described. FIG. 2 is a flowchart illustrating an example of a predetermined time control routine executed by the HVECU 70 of the embodiment. This routine is repeatedly executed every predetermined time (for example, every several milliseconds) at a predetermined time.

  When the control routine is executed at a predetermined time, the HVECU 70 first stores the accelerator opening Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 88, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2, and the storage of the battery 50. Data necessary for control such as ratio SOC, road surface gradient θrg from the gradient sensor 89, travel time T and travel distance L from the start of reverse travel (for example, when the shift position SP is set to the R position), and so on are input. (Step S100). Here, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 are values calculated from the motor ECU 40 based on the rotational positions θm1 and θm2 of the rotors of the motors MG1 and MG2 detected by the rotational position detection sensors 43 and 44. The input was made by communication. Further, as the storage ratio SOC of the battery 50, a value calculated based on the integrated value of the charge / discharge current Ib of the battery 50 detected by the current sensor 51b is input from the battery ECU 52 by communication. As the travel time T, the time value of a timer whose time is disclosed at the start of reverse travel is input. As the travel distance L, a value calculated based on the integrated value of the vehicle speed V from the start of reverse travel is input.

  When the data is input in this way, the required torque Tr * required for traveling (required for the drive shaft 36) is set based on the input accelerator opening Acc and the vehicle speed V (step S110), and the set required torque Tr is set. The required power Pr * required for traveling is calculated by multiplying * by the rotational speed Nr of the drive shaft 36 (step S120). Here, in the embodiment, the required torque Tr * is stored in a ROM (not shown) as a required torque setting map by predetermining the relationship among the accelerator opening Acc, the vehicle speed V, and the required torque Tr *. When Acc and vehicle speed V are given, the corresponding required torque Tr * is derived and set from the stored map. An example of the required torque setting map is shown in FIG. As shown in the figure, the required torque Tr * is set to a negative value (value in the reverse travel direction). Further, the rotational speed Nr of the drive shaft 36 can be calculated by dividing the rotational speed Nm2 of the motor MG2 by the gear ratio Gr of the reduction gear 35, or can be calculated by multiplying the vehicle speed V by a conversion factor. Hereinafter, the required torque Tr * and the required power Pr * set in the processes of steps S110 and S120 may be referred to as an accelerator-corresponding required torque Tracc and an accelerator-corresponding required power Prac, respectively.

  Subsequently, a target rotational speed Ne * and a target torque Te * as target operating points of the engine 22 are set by an engine target operating point setting process described later (step S130). Then, using the target rotational speed Ne * of the engine 22, the rotational speed Nr (= Nm2 / Gr) of the drive shaft 36, and the gear ratio ρ of the planetary gear 30, the target rotational speed Nm1 * of the motor MG1 is calculated by the following equation (1). Using the calculated target rotational speed Nm1 *, the current rotational speed Nm1 of the motor MG1, the target torque Te * of the engine 22 and the gear ratio ρ of the planetary gear 30, the torque command Tm1 * of the motor MG1 is given by equation (2). Is calculated (step S140). Here, Expression (1) is a dynamic relational expression for the rotating element of the planetary gear 30. FIG. 4 shows an example of a collinear diagram showing the dynamic relationship between the rotational speed and torque of the rotating element of the planetary gear 30 at a predetermined time. In the figure, 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 indicates the rotation speed of the motor MG2. The rotational speed Nr of the ring gear 32 (drive shaft 36) obtained by dividing the number Nm2 by the gear ratio Gr of the reduction gear 35 is shown. In the figure, two thick arrows on the R axis indicate torque output from the motor MG1 and acting on the drive shaft 36 via the planetary gear 30, and drive shaft 36 output from the motor MG2 and via the reduction gear 35. Torque acting on is shown. Expression (1) can be easily derived by using this alignment chart. Expression (2) is a relational expression in feedback control for rotating the motor MG1 at the target rotational speed Nm1 * (rotating the engine 22 at the target rotational speed Ne *), and the first term on the right side is the feedforward term. And the second and third terms on the right side are the proportional and integral terms of the feedback term. In Expression (2), “k1” in the second term on the right side is the gain of the proportional term, and “k2” in the third term on the right side is the gain of the integral term.

Nm1 * = Ne * ・ (1 + ρ) / ρ-Nm2 / (Gr ・ ρ) (1)
Tm1 * =-ρ ・ Te * / (1 + ρ) + k1 (Nm1 * -Nm1) + k2∫ (Nm1 * -Nm1) dt (2)

  Then, as shown in the following equation (3), the torque command Tm1 of the motor MG1 is set to the required torque Tr * (the accelerator-corresponding required torque Tracc or a value reset by the engine target operation point setting process described later (limit required torque Trmod)). A value obtained by dividing * by the gear ratio ρ of the planetary gear 30 is added and further divided by the gear ratio Gr of the reduction gear 35 to calculate a temporary torque Tm2tmp as a temporary value of the torque command Tm2 * of the motor MG2. In step S150, as shown in equation (4), the temporary torque Tm2tmp of the motor MG2 is limited by the negative torque limit Tm2lim (with a lower limit guard), and the torque command Tm2 * of the motor MG2 is set (step S160). Here, Expression (3) can be easily derived by using the alignment chart of FIG. The torque limit Tm2lim is a lower limit (upper limit as an absolute value) of torque that may be output from the motor MG2. For example, a torque having a negative rated value corresponding to the rotational speed Nm2 of the motor MG2 is used. it can.

Tm2tmp = (Tr * + Tm1 * / ρ) / Gr (3)
Tm2 * = max (Tm2tmp, Tm2lim) (4)

  When the target rotational speed Ne * and target torque Te * of the engine 22 and the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are set in this way, the target rotational speed Ne * and target torque Te * of the engine 22 are set in the engine ECU 24. The torque commands Tm1 * and Tm2 * for the motors MG1 and MG2 are transmitted to the motor ECU 40 (step S170), and this routine ends. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * of the engine 22 takes in the intake air of the engine 22 so that the engine 22 is operated at an operating point consisting of the target rotational speed Ne * and the target torque Te *. Perform quantity control, fuel injection control, ignition control, etc. The motor ECU 40 that receives the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 controls the switching elements of the inverters 41 and 42 so that the motors MG1 and MG2 are driven by the torque commands Tm1 * and Tm2 *. Do.

  Next, the processing of step S130 of the predetermined time control routine of FIG. 2, that is, the processing of setting the target rotational speed Ne * and the target torque Te * of the engine 22 by the engine target operation point setting processing illustrated in FIG. explain.

  In the engine target operation point setting process, the HVECU 70 first sets the required charging power Pch * of the battery 50 based on the storage ratio SOC of the battery 50 (step S200). Here, in the embodiment, the required charging power Pch * of the battery 50 is determined by storing the relationship between the storage ratio SOC of the battery 50 and the required charging power Pch * in advance in a ROM (not shown). If so, the corresponding required charging power Pch * is derived from the stored map and set. The required charging power Pch * is within a range larger than 0 (within the charging side) when the storage rate SOC is smaller than the target rate SOC * (for example, 50%, 55%, 60%, etc.). A smaller value is set to increase, and when the power storage rate SOC is larger than the target rate SOC *, the power storage rate SOC decreases within a range smaller than the value 0 (within the discharge side range) (the absolute value increases as an absolute value). ) Set to trend. During reverse travel, when the engine 22 is operated under load, the engine 22 is driven by torque in the forward travel direction (hereinafter referred to as “direct torque”) output from the engine 22 and acting on the drive shaft 36 via the planetary gear 30. The lower limit of the torque that can be output to the shaft 36 increases (the absolute value decreases). For this reason, when charging of the battery 50 is not required, it is preferable to stop the operation of the engine 22 and to run backward by the torque (power) from the motor MG2 without executing the predetermined time control routine of FIG. Considering this, in the following description, it is assumed that the engine 22 needs to be loaded (charge of the battery 50 is required).

  Subsequently, using the required torque Tr * (accelerator-corresponding required torque Tacc), the torque limit Tm2lim of the motor MG2, the gear ratio ρ of the planetary gear 30, and the gear ratio Gr of the reduction gear 35, the engine 22 is expressed by the following equation (5). Upper limit torque Temax is calculated (step S210). Here, in Expression (5), “Tm2lim · Gr” indicates a lower limit of torque that can be output from the motor MG2 to the drive shaft 36 (upper limit of torque in the reverse travel direction). Further, “Temax / (1 + ρ)” obtained by dividing both sides of the formula (5) by “1 + ρ” indicates the upper limit of the direct torque from the engine 22 (the upper limit of the torque in the forward travel direction). Therefore, the expression (5) indicates that the upper limit torque Temax is set so that the required torque Tr * can be output to the drive shaft 36 by the torque Temax / (1 + ρ) in the forward travel direction and the torque Tm2lim · Gr in the reverse travel direction. Means to calculate. As can be seen from equation (5), the upper limit torque Temax decreases as the required torque Tr * (accelerator-corresponding required torque Tacc) is smaller (larger as the torque in the reverse travel direction).

  Temax = (Tr * -Tm2lim ・ Gr) ・ (1 + ρ) (5)

  Then, an upper limit rotational speed Nemax of the engine 22 is set based on the rotational speed Nr (= Nm2 / Gr) of the drive shaft 36 (step S220), and the product of the upper limit torque Temax and the upper limit rotational speed Nemax of the engine 22 is set to the engine 22. Is set to the upper limit power Pemax (step S230). Here, the upper limit rotation speed Nemax is calculated by the following method in the embodiment. First, using the upper limit rotational speed Nm1max as the rotational speed of the rated value on the positive side of the motor MG1, the rotational speed Nr of the drive shaft 36, and the gear ratio ρ of the planetary gear 30 (the number of teeth of the sun gear / the number of teeth of the ring gear) The upper limit rotational speed Nemax (mg1) of the engine 22 based on the performance of the motor MG1 is calculated by the following equation (6). Here, Equation (6) can be easily derived by using the alignment chart of FIG. 4 described above. Subsequently, the upper limit rotational speed Npinmax as the rotational speed of the positive rated value of the pinion gear 33 of the planetary gear 30, the rotational speed Nr of the drive shaft 36, and the gear ratio with respect to the pinion gear 33 of the planetary gear 30 (number of teeth of the pinion gear 33 / ring gear 32 And the upper limit rotational speed Nemax (pin) of the engine 22 based on the performance of the pinion gear 33 is calculated by the equation (7). Then, as shown in Expression (8), the minimum value of the upper limit speed Nemax (mg1), Nemax (pin) of the engine 22 and the upper limit speed Nemax (eg) as the rated speed of the engine 22 is a value. At 0, the lower limit is guarded and the upper limit speed Nemax of the engine 22 is set. An example of the relationship between the rotational speed Nr of the drive shaft 36 and the upper limit rotational speed Nemax of the engine 22 is shown in FIG. Then, by setting the upper limit rotational speed Nemax to the target rotational speed Ne * of the engine 22 in the process of step S350 described later, the rotational speed of the engine 22 is protected while protecting the engine 22, the motor MG1, and the pinion gear 33 of the planetary gear 30. Can be increased. As a result, when power smaller than the upper limit power Pemax is output from the engine 22, the torque output from the engine 22 can be reduced as compared with the engine 22 operating at a speed smaller than the upper limit speed Nemax. The direct torque (torque in the forward travel direction) from the engine 22 can be reduced. As described above, the lower the required torque Tr * (the greater the torque in the reverse travel direction), the smaller the upper limit torque Temax. Therefore, the upper limit power Pemax also decreases as the required torque Tr * decreases.

Nemax (mg1) = ρ ・ Nm1max / (1 + ρ) + Nm2 / (Gr ・ (1 + ρ)) (6)
Nemax (pin) = Nm2 / Gr + γ ・ Npinmax (7)
Nemax = max (min (Nemax (mg1), Nemax (pin), Nemax (eg)), 0) (8)

  Next, the required power Pr * is compared with the upper limit power Pemax of the engine 22 (step S240), and a value (Pr * + Pch *) obtained by adding the charge required power Pch * of the battery 50 to the required power Pr * is calculated. It is compared with the upper limit power Pemax (step 250). The processes in steps S240 and S250 are performed for the first time during the current execution of the predetermined time control routine (engine target operation point setting process in FIG. 5) (required power Pr * in the processes in steps S330 and S340 described later). Or when the required torque Tr * is not reset), the accelerator required power Prac is compared with the upper limit power Pemax, and the value (Prac + Pch *) obtained by adding the required charge power Pch * to the accelerator required power Prac is set as the upper limit. The process is compared with the power Pemax, and after the second execution of the predetermined time control routine of FIG. 2 (after resetting the required power Pr * and the required torque Tr * in the processes of steps S330 and S340). Compares the reset required power Pr * with the upper limit power Pemax. Value obtained by adding the charging power demand Pch * in power demand Pr * after setting the process of comparing the upper limit power Pemax a. Hereinafter, first, the case where the process of step S240, S250 is the first time will be described, and then the second time or later will be described.

  When the processing of steps S240 and S250 is the first time, when the required power Pr * and the value (Pr * + Pch *) are less than or equal to the upper limit power Pemax of the engine 22, that is, the accelerator-corresponding required power Prac and the value (Prac + Pch *) are upper limits. When the power is less than Pemax, the value (Pr * + Pch *) is set to the target power Pe * of the engine 22 (step S260), the upper limit rotational speed Nemax of the engine 22 is set to the target rotational speed Ne * of the engine 22, and the target The target torque Te * of the engine 22 is set by dividing the power Pe * by the target rotational speed Ne * of the engine 22 (step S350), and the engine target operation point setting process is terminated. Thus, by setting a value (Pr * + Pch *) equal to or lower than the upper limit power Pemax (= Temax · Nemax) to the target power Pe * and setting the upper limit rotation speed Nemax to the target rotation speed Ne *, the target torque Te * is set. Is a value less than or equal to the upper limit torque Temax.

  In this case, a value equal to or lower than the upper limit torque Temax is set as the target torque Te * in the process of step S350, and the temporary torque Tm2tmp of the motor MG2 is set using the accelerator-corresponding required torque Tacc in the process of step S150 of FIG. become. Therefore, the temporary torque Tm2tmp of the motor MG2 is basically a value within the range of the torque limit Tm2lim from the relationship between the feedforward term of the above-described equation (2) and the equations (3) and (5). . Therefore, in the process of step S160 in FIG. 2, the temporary torque Tm2tmp is set to the torque command Tm2 *. As a result, the sum of the accelerator-corresponding required torque Tacc and the cancel torque Tc for canceling the direct torque from the engine 22 can be output from the motor MG2 to the drive shaft 36, and the accelerator-corresponding required torque Tracc ( It is possible to travel backward by the accelerator required power Prac). In this case, a value (Prac + Pch *) larger than the accelerator-corresponding required power Prac is set as the target power Pe * in the process of step S260. Therefore, the battery 50 can be charged with electric power corresponding to the charging request power Pch *. Thereby, the fall of the electrical storage ratio SOC of the battery 50 can be suppressed.

  When the processing of steps S240 and S250 is the first time, when the required power Pr * is less than or equal to the upper limit power Pemax of the engine 22 and the value (Pr * + Pch *) is larger than the upper limit power Pemax of the engine 22, that is, the accelerator-corresponding required power When Prac is less than or equal to the upper limit power Pemax and the value (Prac + Pch *) is greater than the upper limit power Pemax, the upper limit power Pemax (= Nemax · Temax) is set as the target power Pe * of the engine 22 (step S270). A value obtained by setting the number Nemax to the target rotational speed Ne * of the engine 22 and dividing the target power Pe * by the target rotational speed Ne * of the engine 22, that is, the upper limit torque Temax is set to the target torque Te * of the engine 22. Set (Step S3 0), and terminates the engine target drive point setting process.

  In this case, the upper limit torque Temax is set to the target torque Te * in the process of step S350, and the temporary torque Tm2tmp of the motor MG2 is set using the accelerator required torque Trac in the process of step S150 of FIG. Therefore, as in the case where the accelerator-corresponding required power Prac and the value (Prac + Pch *) are equal to or lower than the upper limit power Pemax, the vehicle can travel backward by the accelerator-corresponding required torque Tracc (accelerator-corresponding required power Prac). In this case, the upper limit power Pemax equal to or higher than the accelerator-corresponding required power Prac is set as the target power Pe * in the process of step S270. Therefore, when the accelerator-corresponding required power Prac is smaller than the upper limit power Pemax, the battery 50 can be charged with power corresponding to a value obtained by subtracting the accelerator-corresponding required power Prac from the upper limit power Pemax (Pemax−Prac). When the power Prac is equal to the upper limit power Pemax, the battery 50 is not charged or discharged. Thereby, the fall of the electrical storage ratio SOC of the battery 50 can be suppressed.

  When the process of step S240 is the first time, when the required power Pr * is greater than the upper limit power Pemax of the engine 22, that is, when the accelerator-corresponding required power Prac is greater than the upper limit power Pemax, the upper limit power Pemax is set to the target power Pe of the engine 22. * Is set (step S280). Then, the upper limit power Pemax is subtracted from the required power Pr * to calculate an assumed discharge power Pdies that is assumed to be discharged from the battery 50 when traveling with the required power Pr * (step S290), and the storage ratio of the battery 50 The value obtained by subtracting the allowable lower limit rate SOCmin from the SOC (SOC-SOCmin) is divided by the assumed discharge power Pdies, and the remaining travelable time Trun that can be driven until the storage rate SOC of the battery 50 reaches the allowable lower limit rate SOCmin is calculated. At the same time, the remaining travelable distance Lrun that can be traveled until the storage rate SOC of the battery 50 reaches the allowable lower limit rate SOCmin is calculated by multiplying the vehicle speed V by the remaining travelable time Trun (step S300). Here, the allowable lower limit ratio SOCmin is determined according to the characteristics of the battery 50, and is, for example, 20%, 25%, 30%, or the like.

  Subsequently, the remaining target travel time Trun * and the remaining target travel distance Lrun * are set based on the travel time T from the start of reverse travel to the present, the travel distance L, and the road surface gradient θrg (step S310). Here, the remaining target travel time Trun * is a lower limit value of the time from the present time when continuation of the reverse travel is desired to be ensured. In the embodiment, the reverse travel is determined from the total target travel time Trunsum from the start of the reverse travel based on the road surface gradient θrg. The travel time T from the start of travel to the present is reduced to obtain. The total target travel time Trunsum is a map in which the relationship between the road surface gradient θrg and the total target travel time Trunsum is determined in advance and stored in a ROM (not shown) as a total target travel time setting map, and the road surface gradient θrg is stored. The corresponding total target travel time Trunsum is derived and set. Further, the remaining target travel distance Lrun * is a lower limit value of the distance from the present time at which continuation of the reverse travel is desired to be ensured. In the embodiment, the reverse travel is performed from the total target travel distance Lrunsum from the start of the reverse travel based on the road surface gradient θrg. The mileage L from the start to the present is reduced to obtain. The total target travel distance Lrunsum is a map in which the relationship between the road surface gradient θrg and the total target travel distance Lrunsum is determined in advance and stored in a ROM (not shown) as a total target travel distance setting map, and the road surface gradient θrg is stored. The corresponding total target travel distance Lrunsum is derived and set. An example of the total target travel time setting map is shown in FIG. 7, and an example of the total target travel distance setting map is shown in FIG. As shown in FIGS. 7 and 8, the total target travel time Trunsum and the total target travel distance Lrunsum are set so as to become longer as the road surface gradient θrg is smaller. In general, it is relatively possible to travel backward on a flat road or an uphill road with a small road gradient θrg for a certain amount of time or distance, but on an uphill road with a large road surface gradient θrg over a certain amount of time or distance. Based on the reason that it is considered very rare to travel backward.

  When the remaining target travel time Trun * and the remaining target travel distance Lrun * are thus set, the remaining travelable time Trun is compared with the remaining target travel time Trun * and the remaining travelable distance Lrun is compared with the remaining target travel distance Lrun *. (Step S320).

  If the remaining travelable time Trun is equal to or longer than the remaining target travel time Trun * and the remaining travelable distance Lrun is equal to or greater than the remaining target travel distance Lrun * in step S320, the upper limit speed Nemax of the engine 22 is set to the target speed Ne of the engine 22. * And a value obtained by dividing the target power Pe * (in this case, the upper limit power Pemax (= Nemax · Temax)) by the target rotation speed Ne * of the engine 22, that is, the upper limit torque Temax is the target of the engine 22. The torque Te * is set (step S350), and the engine target operation point setting process is terminated. In this case, the vehicle travels backward for the remaining target travel time Trun * or more and the remaining target travel distance Lrun * or more from the present, that is, the reverse travel for the value (T + Trun *) or more and the value (L + Lrun *) or more from the start of the reverse travel. It is thought that can be performed.

  In this case, the upper limit torque Temax is set to the target torque Te * in the process of step S350, and the temporary torque Tm2tmp of the motor MG2 is set using the accelerator required torque Trac in the process of step S150 of FIG. Therefore, as in the case where the accelerator-corresponding required power Prac and the value (Prac + Pch *) are equal to or lower than the upper limit power Pemax, the vehicle can travel backward by the accelerator-corresponding required torque Tracc (accelerator-corresponding required power Prac). In this case, the upper limit power Pemax smaller than the accelerator-corresponding required power Prac is set as the target power Pe * in the process of step S280. Therefore, in order to travel backward with the accelerator-corresponding required power Prac, the battery 50 is discharged with electric power corresponding to a value (Pr * −Pemax) obtained by subtracting the upper limit power Pemax from the required power Pr *.

  In step S320, when the remaining travelable time Trun is less than the remaining target travel time Trun * or when the remaining travelable distance Lrun is less than the remaining target travel distance Lrun *, the required power Pr * is decreased by a predetermined value ΔPr and reset. (Step S330), the reset required power Pr * is divided by the rotational speed Nr (= Nm2 / Gr) of the drive shaft 36 to reset the required torque Tr * (step S340), and the process returns to step S240. . Since the process of steps S240 and S250 is considered for the first time, the processes of steps S330 and S340 are also performed for the first time. Therefore, the processing in steps S330 and S340 reduces the required power Pr * from the accelerator-corresponding required power Prac by a predetermined value ΔPr, and accordingly increases the required torque Tr * from the accelerator-corresponding required torque Tracc (smaller as an absolute value). Process). Here, the predetermined value ΔPr is, for example, 1 kW, 2 kW, 3 kW, or the like. The required power Pr * reset in step S330 is used when determining how to set the target power Pe * in the processing of steps S240 and S250, and the required torque Tr * reset in step S340. Is used when setting the temporary torque Tm2tmp of the motor MG2 in the process of step S150 of FIG.

  Next, the case where the processes in steps S240 and S250 are the second and subsequent times (after the required power Pr * and the required torque Tr * are reset in the processes in steps S330 and S340) will be described.

  When the process in step S240 is performed for the second time or later and the required power Pr * after resetting is greater than the upper limit power Pemax, the processes in and after step S280 are executed again. In this case, by reducing the required power Pr * by a predetermined value ΔPr from before the resetting, the assumed discharge power Pdies calculated in step S290 is reduced, and the remaining travelable time Trun calculated in step S300 and the remaining travelable The distance Lrun becomes longer. In step S320, when the remaining travelable time Trun is less than the remaining target travel time Trun * or when the remaining travelable distance Lrun is less than the remaining target travel distance Lrun *, the required power Pr * and the required torque Tr * are set again. (Steps S330 and S340), the process returns to Step S240. In this way, it is determined in step S240 that the required power Pr * is less than or equal to the upper limit power Pemax, or the remaining travelable time Trun is greater than or equal to the remaining target travel time Trun * and the remaining travelable distance Lrun remains in step S320. The processes in steps S240 and S280 to S340 are repeatedly executed until it is determined that the target travel distance Lrun * is not less than the target travel distance Lrun *, and the required power Pr * is decreased by a predetermined value ΔPr. Hereinafter, immediately before it is determined in step S240 that the required power Pr * has become equal to or less than the upper limit power Pemax, or in step S320, the remaining travelable time Trun is greater than or equal to the remaining target travel time Trun * and the remaining travelable distance Lrun is the remaining target. The latest requested power Pr * and the requested torque Tr * set immediately before it is determined that the travel distance Lrun * or more may be referred to as the restricted requested power Prmod and the restricted requested torque Trmod, respectively.

  If it is determined in step S320 that the remaining travelable time Trun is equal to or greater than the remaining target travel time Trun * and the remaining travelable distance Lrun is equal to or greater than the remaining target travel distance Lrun *, the upper limit rotational speed Nemax of the engine 22 is set to the engine. 22 and the target power Pe * (in this case, the upper limit power Pemax (= Nemax · Temax)) divided by the target engine speed Ne * of the engine 22, that is, the upper limit torque Temax is set to the target torque Te * of the engine 22 (step S350), and the engine target operation point setting process is terminated. In this case, the vehicle travels backward for the remaining target travel time Trun * or more and the remaining target travel distance Lrun * or more from the present, that is, the reverse travel for the value (T + Trun *) or more and the value (L + Lrun *) or more from the start of the reverse travel. It is thought that can be performed.

  In this case, the upper limit torque Temax is set to the target torque Te * in the process of step S350, and the temporary torque Tm2tmp of the motor MG2 is set using the limit request torque Trmod in the process of step S150 of FIG. Therefore, the temporary torque Tm2tmp becomes a value within the range of the torque limit Tm2lim, and the temporary torque Tm2tmp is set to the torque command Tm2 * in the process of step S160 in FIG. As a result, the vehicle travels backward with a limited required torque Trmod (restricted required power Prmod) that is limited by the accelerator-corresponding required torque Trac (accelerator-required required power Prac). In this case, the upper limit power Pemax smaller than the limit required power Prmod is set as the required power Pe * in the process of step S280. Therefore, the battery 50 is discharged with electric power corresponding to a value (Prmod−Pemax) obtained by subtracting the upper limit power Pemax from the limit request power Prmod. Thereby, compared with what drives backward with the accelerator corresponding | compatible required power Prac, ie, discharges the battery 50 with the electric power equivalent to a value (Prac-Pemax), the discharge electric power from the battery 50 is made small, It is possible to moderate the decrease in the power storage rate SOC and increase the time and distance in which the reverse travel can be continued.

  On the other hand, when it is determined in step S240 that the required power Pr * has become equal to or lower than the upper limit power Pemax, the processes after step S250 are executed, and the engine target operation point setting process is terminated.

  In this case, the upper limit torque Temax is set to the target torque Te * in the process of step S350, and the temporary torque Tm2tmp of the motor MG2 is set using the limit request torque Trmod in the process of step S150 of FIG. Therefore, the vehicle travels backward with the limited required torque Trmod (restricted required power Prmod) that is limited by the accelerator required torque Trac (accelerator required power Prac). In this case, the target power Pe * is set to a value higher than the limit required power Prmod (Prmod + Pch *) or an upper limit power Pemax greater than or equal to the limit required power Prmod in the process of step S260 or S270 according to the limit required power Prmod. Become. Therefore, the battery 50 is not charged or charged / discharged. Thereby, the fall of the electrical storage ratio SOC of the battery 50 can be suppressed.

  FIG. 9 shows an accelerator-corresponding required power Prac when the battery 50 is required to be charged at a predetermined time, a required charging power Pch * of the battery 50, a target power Pe * of the engine 22, an actual traveling power (actual Pr), It is explanatory drawing which shows an example of the relationship of the actual charging / discharging electric power of the battery 50 (actual Pch at the time of charge, real Pdi at the time of discharge). In the drawing, the upper limit power Pemax is smaller as the required power Pr * is larger for the above-described reason.

  As shown on the left side of the figure, when the value (Prac + Pch *) obtained by adding the charging-required power Pch * to the accelerator-corresponding required power Prac is less than or equal to the upper limit power Pemax, the value (Prac + Pch *) is set as the target power Pe *. The vehicle travels backward with the travel power (actual Pr) corresponding to the accelerator-corresponding required power Pracc. At this time, the battery 50 is charged with power (actual Pch) corresponding to the charge request power Pch *.

  As shown in the second from the left in the figure, when the accelerator-corresponding required power Pracc is less than or equal to the upper limit power Pemax and the value (Prac + Pch *) is greater than the upper limit power Pemax, the upper limit power Pemax is set to the target power Pe * and The vehicle travels backward with travel power (actual Pr) corresponding to the required power Pracc. At this time, when the accelerator-corresponding required power Prac is smaller than the upper limit power Pemax, the battery 50 is charged with power (actual Pch) corresponding to a value obtained by subtracting the accelerator-corresponding required power Prac from the upper limit power Pemax. When equal to the upper limit power Pemax, the battery 50 is not charged or discharged.

  As shown in the third from the left in the figure, when the accelerator required power Pracc is greater than the upper limit power Pemax, the remaining travelable time Trun is equal to or longer than the remaining target travel time Trun * and the remaining travelable distance Lrun is the remaining target travel distance. When it is equal to or greater than Lrun *, the upper limit power Pemax is set to the target power Pe *, and the vehicle travels backward with the travel power (actual Pr) corresponding to the accelerator-corresponding required power Prac. At this time, the battery 50 is discharged with electric power (actual Pdi) corresponding to a value obtained by subtracting the upper limit power Pemax from the accelerator-corresponding required power Pracc.

  As shown in the fourth from the left in the figure, when the accelerator required power Pracc is greater than the upper limit power Pemax, the remaining travelable time Trun is less than the remaining target travel time Trun * or the remaining travelable distance Lrun is the remaining target travel. When the distance is less than Lrun *, the upper limit power Pemax is set to the target power Pe *, and the vehicle travels backward with the traveling power (actual Pr) corresponding to the limited required power Prmod smaller than the accelerator-corresponding required power Prac. At this time, the battery 50 is discharged with electric power (actual Pdi) corresponding to a value obtained by subtracting the upper limit power Pemax from the limit request power Prmod. As a result, compared to when the vehicle travels backward with the accelerator-corresponding required power Prac, the discharge power from the battery 50 is reduced, the decrease in the storage rate SOC of the battery 50 is moderated, and the time and distance for which the reverse travel can be continued are reduced. Can be long. That is, it is possible to secure a certain amount of time and distance in which the backward traveling can be continued.

  In the hybrid vehicle 20 of the embodiment described above, at a predetermined time when the engine 22 is traveling backward while being loaded, the accelerator-corresponding required torque Tracc and the cancel torque for canceling the direct torque from the engine 22 are basically , The upper limit power Pemax of the engine 22 is set so that the torque MG2 can be output from the motor MG2 to the drive shaft 36, the engine 22 is operated within the range of the upper limit power Pemax or less, and the accelerator-corresponding required torque Tracc The engine 22 and the motors MG1 and MG2 are controlled so that the vehicle travels with the accelerator required power Prac that is the required power Pr * corresponding to. Thereby, it can suppress that the running performance at the time of reverse running falls. When the accelerator-corresponding required power Prac is larger than the upper limit power Pemax at a predetermined time, the upper limit power Pemax is set to the target power Pe * of the engine 22, and the remaining value is obtained by subtracting the upper limit power Pemax from the required power Pr *. The travelable time Trun and the remaining travelable distance Lrun are calculated, and when the remaining travelable time Trun is less than the remaining target travel time Trun * or when the remaining travelable distance Lrun is less than the remaining target travel distance Lrun *, an accelerator response request Control is performed so that the vehicle travels with a limited required power Prmod smaller than the power Prac. As a result, the discharge power from the battery 50 can be reduced, the decrease in the storage rate SOC of the battery 50 can be moderated, and the time and distance in which the reverse travel can be continued can be lengthened. That is, it is possible to secure a certain amount of time and distance in which the backward traveling can be continued.

  Moreover, when the remaining travelable time Trun is less than the remaining target travel time Trun * or the remaining travelable distance Lrun is less than the remaining target travel distance Lrun * at a predetermined time, the remaining travelable time Trun is the remaining target travel time Trun *. The limit required power Prmod is set so that the remaining travelable distance Lrun is equal to or greater than the remaining target travel distance Lrun * (required power Pr * is made smaller than the accelerator-corresponding required power Prac). Thereby, it is possible to make it possible to travel backward from the present over the remaining travelable time Trun * over the remaining target travel distance Lrun *. That is, it is possible to sufficiently lengthen the time and distance in which the backward traveling can be continued.

  In the hybrid vehicle 20 of the embodiment, when the accelerator-corresponding required power Prac is larger than the upper limit power Pemax at a predetermined time, the remaining travelable time Trun is less than the remaining target travel time Trun * or the remaining travelable distance Lrun is the remaining target travel distance. When it is less than Lrun *, it is decreased by a predetermined value ΔPr from the accelerator-related required power Prac until the remaining travelable time Trun is equal to or greater than the remaining target travel time Trun * and the remaining travelable distance Lrun is equal to or greater than the remaining target travel distance Lrun *. The limit request power Prmod is set, but the limit request power Prmod may be set by subtracting the predetermined value ΔPr2 only once from the accelerator-corresponding request power Prac. In this case, the remaining travelable time Trun and the remaining travelable distance Lrun calculated using the limit required power Prmod may not be equal to or longer than the remaining target travel time Trun * and the remaining target travel distance Lrun *. Compared with the case where the vehicle is not set (the vehicle is controlled so as to travel with the accelerator-corresponding required power Prac), the time and distance in which the backward traveling can be continued can be increased.

  In the hybrid vehicle 20 of the embodiment, when the accelerator-corresponding required power Prac is larger than the upper limit power Pemax at a predetermined time, the remaining travelable time Trun is less than the remaining target travel time Trun * or the remaining travelable distance Lrun is the remaining target travel distance. When less than Lrun *, the required power Pr * is determined from the accelerator-corresponding required power Prac until the remaining travelable time Trun is equal to or greater than the remaining target travel time Trun * and the remaining travelable distance Lrun is equal to or greater than the remaining target travel distance Lrun *. The limit required power Prmod is set by decreasing the value ΔPr, but the required power Pr * has reached a predetermined value Pref (for example, several kW) while the required power Pr * is being reduced. Sometimes, the required power Pr * at that time is limited to the limit request parameter. It may be set to over Prmod.

  In the hybrid vehicle 20 of the embodiment, when the accelerator-corresponding required power Pracc is larger than the upper limit power Pemax at a predetermined time, the remaining travelable time Trun and the remaining travelable distance Lrun are calculated, but only one of them is calculated. It may be a thing. Further, in the embodiment, when the accelerator-corresponding required power Prac is larger than the upper limit power Pemax at a predetermined time, the vehicle travels with the accelerator-corresponding required power Prac according to the remaining travelable time Trun and the remaining travelable distance Lrun, or the limited required power Although it is determined whether the vehicle travels by Prmod, it may be determined only based on the remaining travelable time Trun, or may be determined only based on the remaining travelable distance Lrun.

  In the hybrid vehicle 20 of the embodiment, the remaining target travel time Trun * and the remaining target travel distance Lrun * are set based on the travel time T from the start of reverse travel to the present, the travel distance L, and the road surface gradient θrg. However, it may be set without considering the road surface gradient θrg.

  In the hybrid vehicle 20 of the embodiment, when the required power Pr * is larger than the upper limit power Pemax at a predetermined time, the remaining travelable time Trun and the remaining travelable distance Lrun are calculated. One or both of the remaining travelable distances Lrun may be displayed on the display 90. In this way, the remaining travelable time Trun and the remaining travelable distance Lrun can be notified to the driver.

  In the hybrid vehicle 20 of the embodiment, the upper limit rotational speed Nemax of the engine 22 at a predetermined time is the upper limit rotational speed Nemax (mg1) of the engine 22 based on the performance of the motor MG1 and the upper limit rotational speed of the engine 22 based on the performance of the pinion gear 33. The minimum value of the number Nemax (pin) and the upper limit rotational speed Nemax (eg) as the rated value of the engine 22 is set to a lower limit guard with a value of 0, but only the rotational speed Nr of the drive shaft 36 is set. It may be set accordingly or a predetermined value may be used.

  In the hybrid vehicle 20 of the embodiment, the required charging power Pch * of the battery 50 at a predetermined time is set according to the storage ratio SOC of the battery 50. However, in addition to the storage ratio SOC, the terminal voltage of the battery 50 It may be set in consideration of Vb, battery temperature Tb, and the like.

  In the hybrid vehicle 20 of the embodiment, the planetary gear 30 is configured as a single pinion type, but on the alignment chart, it is aligned with the drive shaft 36, the crankshaft 26 of the engine 22, and the rotation shaft of the motor MG1. As long as three rotating elements are connected, it may be configured as a double pinion type.

  In the hybrid vehicle 20 of the embodiment, the rotation shaft of the motor MG2 is connected to the drive shaft 36 via the reduction gear 35, but via a stepped transmission or a continuously variable transmission such as two or three stages. It may be connected to the drive shaft 36, or may be directly connected without passing through the reduction gear 35 or the transmission.

  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 the “engine”, the motor MG1 corresponds to the “first motor”, the planetary gear 30 corresponds to the “planetary gear”, the motor MG2 corresponds to the “second motor”, and the battery 50 Corresponds to the “battery”, and is based on the HVECU 70 that executes the control routine at a predetermined time of FIG. 2 including the engine target operation point setting process of FIG. 5, and the target rotational speed Ne * and the target torque Te * of the engine 22 from the HVECU 70. The engine ECU 24 that controls the engine 22 and the motor ECU 40 that controls the motors MG1, MG2 (inverters 41, 42) based on the torque commands Tm1 *, Tm2 * of the motors MG1, MG2 from the HVECU 70 are "control means". It corresponds to.

  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 Hybrid Vehicle, 22 Engine, 24 Electronic Control Unit (Engine ECU) for Engine, 26 Crankshaft, 28 Damper, 30 Planetary Gear, 31 Sun Gear, 32 Ring Gear, 33 Pinion Gear, 34 Carrier, 35 Reduction Gear, 36 Drive Shaft, 40 Motor Electronic control unit (motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 50 battery, 51a voltage sensor, 51b current sensor, 51c temperature sensor, 52 battery electronic control unit (battery ECU), 60 gear Mechanism, 62 Differential gear, 63a, 63b Drive wheel, 70 Hybrid electronic control unit (HVECU), 80 Ignition switch, 81 Shift lever, 82 Shift position sensor 83 accelerator pedal, 84 an accelerator pedal position sensor, 85 brake pedal, 86 a brake pedal position sensor, 88 vehicle speed sensor, 89 slope sensor, 90 a display, MG1, MG2 motor.

Claims (5)

Engine,
A first motor capable of inputting and outputting power;
A drive shaft connected to an axle, an output shaft of the engine, and a rotary shaft of the first motor are connected so that three rotary elements are arranged in the order of the drive shaft, the output shaft, and the rotary shaft on a collinear diagram. Planetary gears,
A second motor capable of inputting and outputting power to the drive shaft;
A battery capable of exchanging electric power with the first motor and the second motor;
A hybrid vehicle comprising:
At a predetermined time when the engine travels backward while performing a load operation, the requested torque in the reverse travel direction required for the drive shaft and the torque in the forward travel direction that acts on the drive shaft in accordance with the load operation of the engine are canceled. The upper limit power of the engine is set so that the sum of the cancel torque and the torque can be output from the second motor to the drive shaft, and the target power of the engine is set within a range equal to or lower than the upper limit power. And setting means for controlling the engine, the first motor, and the second motor so that the target power is output from the engine and travels with the corresponding required power corresponding to the required torque,
The control means sets the upper limit power to the target power when the corresponding required power is larger than the upper limit power at the predetermined time, and travels backward according to a difference between the corresponding required power and the upper limit power. A travelable value that is at least one of a continuable time and a distance is set, and when the travelable value is equal to or greater than a threshold value, control is performed so that the vehicle travels with the corresponding required power, and when the travelable value is less than the threshold value, Control to drive with limited required power smaller than the corresponding required power,
A hybrid vehicle characterized by that. The hybrid vehicle according to claim 1,
The control means sets the limit required power so that the travelable value is equal to or greater than the threshold when the corresponding required power is greater than the upper limit power and the travelable value is less than the threshold at the predetermined time. To
A hybrid vehicle characterized by that. A hybrid vehicle according to claim 1 or 2,
The threshold value is set to tend to be smaller as at least one of the time and distance from the start of reverse travel is longer,
A hybrid vehicle characterized by that. A hybrid vehicle according to claim 3,
The threshold value is set so as to increase as the road surface gradient decreases.
A hybrid vehicle characterized by that. A hybrid vehicle according to any one of claims 1 to 4,
When the corresponding required power is greater than the upper limit power at the predetermined time, the control means divides the difference between the storage ratio of the battery and the allowable lower limit ratio by the difference between the corresponding required power and the upper limit power. Calculating a time during which the reverse travel can be continued, and calculating a distance at which the reverse travel can be continued as a product of a vehicle speed and the calculated time;
A hybrid vehicle characterized by that.

Images