JP5842730B2 - Hybrid car - Google Patents

Description

  The present invention relates to a hybrid vehicle. More specifically, the present invention relates to an engine, a first motor, a driving shaft coupled to an axle, an output shaft of the engine, and a planetary gear having three rotating elements connected to a rotating shaft of the first motor. The present invention relates to a hybrid vehicle including a second motor having a rotation shaft connected to a drive shaft, and a battery capable of exchanging electric power with the first motor and the second motor.

  Conventionally, in this type of hybrid vehicle, an engine, a first motor, a drive shaft coupled to an axle, an output shaft of the engine, and a rotating shaft of the first motor are connected to a ring gear, a carrier, and a sun gear. A distribution integration mechanism, a second motor having a rotation shaft connected to the drive shaft, and a battery that exchanges power with the first motor and the second motor, and when the second motor cannot be driven, A basic throttle opening for canceling the deviation from the current rotational speed, and a correction opening for canceling the fluctuation of the torque acting on the engine side when the negative torque from the first motor changes. An engine that controls the engine by setting the target throttle opening according to the sum has been proposed (see, for example, Patent Document 1). In this hybrid vehicle, by such control, when negative torque is output from the first motor using the reaction force of the engine and positive torque is output to the drive shaft, the negative torque of the first motor is quickly changed. The engine can be stably operated at the target rotational speed.

JP 2006-9664 A

  In the hybrid vehicle described above, when the second motor cannot be driven, the torque from the engine is relatively small, so that the engine stall is sufficiently suppressed when the torque from the first motor increases in the negative direction. It may not be possible. If the engine stalls when the second motor cannot be driven, it will not be possible to continue running. Therefore, one of the problems is to suppress this further.

  The main purpose of the hybrid vehicle of the present invention is to further suppress engine stall when the second motor having the rotation shaft connected to the drive shaft cannot be driven.

  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
An engine, a first motor, a drive shaft connected to an axle, a planetary gear in which three rotation elements are connected to an output shaft of the engine and a rotation shaft of the first motor, and a rotation shaft connected to the drive shaft A hybrid vehicle comprising: the second motor, and a battery capable of exchanging electric power with the first motor and the second motor,
A power for traveling is set as a product of the required torque of the drive shaft and the rotational speed of the drive shaft, and the storage ratio-derived power that is the charge / discharge required power of the battery based on the storage ratio of the battery and the travel power And the engine is operated at a first operating point based on the engine required power and a first constraint on the engine speed and torque, and the requested torque is driven by the engine. Control means for controlling the engine, the first motor and the second motor to be output to a shaft;
In an abnormal state where the second motor cannot be driven, the control means converts an output shaft conversion torque obtained by converting a required torque of the drive shaft into a torque of an output shaft of the engine, and is higher than the output shaft conversion torque and the first constraint. The engine and the first motor are controlled so that the engine is operated at a second operation point consisting of a second restriction on the torque side and the required torque is output to the drive shaft. Means,
This is the gist.

  In the hybrid vehicle according to the present invention, the power for traveling is set as the product of the required torque of the drive shaft and the rotational speed of the drive shaft, and the storage ratio-derived power that is the charge / discharge required power of the battery based on the storage ratio of the battery and the travel The engine required power is set based on the power for the engine, and the engine is operated at the first operating point based on the engine required power and the first constraint on the engine speed and torque, and the required torque is output to the drive shaft. The engine, the first motor, and the second motor are controlled as described above. When the second motor cannot be driven, the output shaft conversion torque obtained by converting the required torque of the drive shaft into the torque of the engine output shaft, and the output shaft conversion torque and the second constraint on the higher torque side than the first constraint. The engine and the first motor are controlled so that the engine is operated at the second operation point consisting of the rotation speed based on the output speed and the required torque is output to the drive shaft. Therefore, since the output shaft equivalent torque is output from the engine at the time of abnormality, the first motor is compared with the one that operates the engine independently (operates so that the difference between the target rotational speed and the current rotational speed is canceled). When the torque from the engine changes, the engine can be further prevented from stalling. Further, by using the second constraint instead of the first constraint at the time of abnormality, it is possible to cope with a large required torque (a rotation speed corresponding to the second constraint can be set). It should be noted that, since power cannot be generated or consumed by the second motor in the event of an abnormality, the power corresponding to the difference between the power output from the engine and the traveling power when the engine is operated at the second operating point. It is considered that the battery is charged and discharged.

  In such a hybrid vehicle of the present invention, the control means is configured such that the power stored in the storage ratio is higher than the estimated charge / discharge power estimated when the battery is charged when the engine is operated at the second operation point. When the battery is large on the charging side, the output shaft equivalent torque, and the rotation speed obtained by dividing the required power of the engine based on the storage ratio-derived power and the traveling power by the output shaft equivalent torque, The engine and the first motor may be controlled so that the engine is operated at a third operation point and the required torque is output to the drive shaft. In general, when the storage ratio of the battery is low, a value on the charging side of the battery is set for the storage ratio-derived power. Therefore, by such control, the battery is charged with power corresponding to the storage ratio-derived power at this time. be able to. In this case, the power due to the power storage ratio may be a power that is set based on the power storage ratio with a predetermined range of the power storage ratio of the battery as a dead zone at the time of the abnormality.

  In the hybrid vehicle of the present invention, the control means sets the temporary required torque corresponding to the accelerator operation amount to the required torque when the abnormality is not occurring, and sets the temporary required torque according to the vehicle speed when the abnormality is abnormal. It is also possible to limit the at least one of the first torque limit and the second torque limit according to the allowable input power of the battery to set the required torque. In this case, the first torque limit tends to decrease as the vehicle speed approaches the reference vehicle speed below the reference vehicle speed at which the rotation speed of the first motor is zero when the engine rotation speed is the lower limit rotation speed. The second torque limit is obtained by dividing the allowable power generation torque of the first motor obtained by dividing the allowable input power of the battery by the rotation speed of the first motor into the torque of the drive shaft. It can also be a torque limit obtained by conversion.

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 drive control routine performed by HVECU70 of an Example. It is explanatory drawing which shows an example of the map for temporary request | requirement torque setting. It is explanatory drawing which shows an example of the normal time temporary charging / discharging request | requirement power setting map. It is explanatory drawing which shows an example of the fuel consumption operation line of the engine 22, and a mode that the target rotational speed Ne * and the target torque Te * are set. 4 is an explanatory diagram showing an example of a collinear diagram showing a dynamic relationship between the number of rotations and torque in a rotating element of the planetary gear 30 when traveling while outputting power from the engine 22. FIG. 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 time of abnormality. It is explanatory drawing which shows an example of the map for vehicle speed origin torque limitation setting. It is explanatory drawing which shows an example of the high torque operation line of the engine 22, and a mode that the temporary rotation speed Netmp is set. It is explanatory drawing which shows an example of the temporary charging / discharging request | requirement power setting map at the time of abnormality. It is explanatory drawing which shows the operating point of the engine 22 at the time of abnormality. It is explanatory drawing which shows an example of the alignment chart which shows the relationship of the rotation speed in the rotation element of the planetary gear 30 at the time of abnormally low vehicle speed. It is explanatory drawing which shows an example of the alignment chart which shows the relationship of the rotation speed in the rotation element of the planetary gear 30 at the time of abnormal predetermined vehicle speed. It is explanatory drawing which shows an example of the alignment chart which shows the relationship of the rotation speed in the rotation element of the planetary gear 30 at the time of abnormally high vehicle speed. 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 drawing, the hybrid vehicle 20 of the embodiment includes an engine 22 that outputs power using gasoline or light oil as a fuel, an engine electronic control unit (hereinafter referred to as an engine ECU) 24 that controls the drive of the engine 22, an engine, and the like. A planetary gear 30 having a carrier connected to the crankshaft 26 and a ring gear connected to a drive shaft 36 connected to drive wheels 38a and 38b via a differential gear 37, and a rotor configured as a synchronous generator motor, for example. Motor MG1 connected to the sun gear of planetary gear 30, for example, a motor MG2 configured as a synchronous generator motor and having a rotor connected to drive shaft 36, inverters 41 and 42 for driving motors MG1 and MG2, Inverters 41 and 42 not shown A motor electronic control unit (hereinafter referred to as a motor ECU) 40 that drives and controls the motors MG1 and MG2 by switching the elements, and a motor MG1, configured as, for example, a lithium ion secondary battery via inverters 41 and 42. A battery 50 that exchanges power with the MG 2, a battery electronic control unit (hereinafter referred to as a battery ECU) 52 that manages the battery 50, and a hybrid electronic control unit (hereinafter referred to as a HVECU) 70 that controls the entire vehicle. Prepare.

  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 that detect the operating state of the engine 22, for example, a water temperature sensor that detects the crank position θcr from the crank position sensor that detects the rotational position of the crankshaft 26 and the coolant temperature of the engine 22. From the cam position sensor for detecting the cooling water temperature Tw from the cylinder, the in-cylinder pressure Pin from the pressure sensor installed in the combustion chamber, the rotational position of the intake valve for intake and exhaust to the combustion chamber and the camshaft for opening and closing the exhaust valve Position θca, throttle position TP from a throttle valve position sensor that detects the position of the throttle valve, intake air amount Qa from an air flow meter attached to the intake pipe, intake air temperature Ta from a temperature sensor also attached to the intake pipe, Installed in the exhaust system The air-fuel ratio AF from the air-fuel ratio sensor and the oxygen signal O2 from the oxygen sensor attached to the exhaust system are input via the input port, and the engine ECU 24 is for driving the engine 22. Various control signals, such as the drive signal to the fuel injection valve, the drive signal to the throttle motor that adjusts the throttle valve position, the control signal to the ignition coil integrated with the igniter, and the opening / closing timing of the intake valve can be changed A control signal to the variable valve timing mechanism is output via the output port. The engine ECU 24 is in communication with the HVECU 70, controls the operation of the engine 22 by a control signal from the HVECU 70, and outputs data related to the operation state of the engine 22 to the HVECU 70 as necessary. 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.

  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 necessary for driving and controlling the motors MG1 and MG2, for example, rotational positions θm1 and θm2 from rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2, and not shown. A phase current applied to the motors MG1 and MG2 detected by the current sensor is input via the input port, and the motor ECU 40 outputs a switching control signal to switching elements (not shown) of the inverters 41 and 42. It is output through the port. The motor ECU 40 is in communication with the HVECU 70, controls the driving of the motors MG1 and MG2 by a control signal from the HVECU 70, and outputs data related to the operating state of the motors MG1 and MG2 to the HVECU 70 as necessary. The motor ECU 40 also calculates the rotational angular velocities ωm1, ωm2 and the rotational speeds Nm1, Nm2 of the motors MG1, MG2 based on the rotational positions θm1, θm2 of the rotors of the motors MG1, MG2 from the rotational position detection sensors 43, 44. ing.

  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 attached to a signal necessary for managing the battery 50, for example, an inter-terminal voltage Vb from a voltage sensor 51a installed between terminals of the battery 50 or an electric power line connected to an output terminal of the battery 50. The charging / discharging current Ib from the current sensor 51b, the battery temperature Tb from the temperature sensor 51c attached to the battery 50, and the like are input, and data relating to the state of the battery 50 is transmitted to the HVECU 70 by communication as necessary. . Further, the battery ECU 52 is a ratio of the capacity of electric power that can be discharged from the battery 50 at that time based on the integrated value of the charge / discharge current Ib detected by the current sensor 51b in order to manage the battery 50. The storage ratio SOC is calculated, and input / output limits Win and Wout, which are allowable input / output powers that may charge / discharge the battery 50, are calculated based on the calculated storage ratio SOC and the battery temperature Tb. 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 limiting limit are set based on the storage ratio SOC of the battery 50. It can be set by setting a correction coefficient and multiplying the basic value of the set input / output limits Win and Wout by the correction coefficient.

  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 degree from the accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. Acc, the brake pedal position BP from the brake pedal position sensor 86 that detects the depression amount of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 88, and the like are input via the input port. As described above, the HVECU 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.

  In the hybrid vehicle 20 of the embodiment thus configured, the required torque Tr * to be output to the drive shaft 36 is calculated based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal by the driver. 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 Tr * is output to the drive shaft 36. As the operation control of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is controlled so that the power corresponding to the required power is output from the engine 22, and all the power output from the engine 22 is transmitted to the planetary gear 30 and the motor. The torque conversion operation mode in which the motor MG1 and the motor MG2 are driven and controlled so that the torque is converted by the MG1 and the motor MG2 and output to the drive shaft 36, and the sum of the required power and the power required for charging and discharging the battery 50 is met. Operation of the engine 22 is controlled so that power is output from the engine 22, and all or part of the power output from the engine 22 with charge / discharge of the battery 50 is torque generated by the planetary gear 30, the motor MG1, and the motor MG2. The required power is output to the drive shaft 36 with conversion. Charge-discharge drive mode for driving and controlling the motors MG1 and MG2, there is a motor operation mode in which operation control to output a power commensurate to stop the operation of the engine 22 to the required power from the motor MG2 to the drive shaft 36.

  Next, the operation of the thus configured hybrid vehicle 20 of the embodiment will be described. FIG. 2 is a flowchart illustrating an example of a drive control routine executed by the HVECU 70 of the embodiment. This routine is repeatedly executed every predetermined time (for example, every several msec).

  When the drive control routine is executed, the HVECU 70 first stores the accelerator opening degree Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 88, the rotational speeds Nm1, Nm2 of the motors MG1, MG2, and the storage ratio of the battery 50. Necessary for control such as abnormality determination flag F indicating whether or not the motor MG2 cannot be driven (torque cannot be output from the motor MG2) due to an abnormality in the SOC, input / output restriction Win, Wout, motor MG2 or inverter 42 A process of inputting data is executed (step S100). Here, the rotational speeds Nm1, Nm2 of the motors MG1, MG2 are calculated from the motor ECU 40 based on the rotational positions θm1, θm2 of the rotors of the motors MG1, MG2 detected by the rotational position detection sensors 43, 44. The input was made by communication. As the storage ratio SOC of the battery 50, a value calculated based on the integrated value of the charge / discharge current Ib detected by the current sensor 51b is input from the battery ECU 52 by communication. The input / output limits Win and Wout of the battery 50 are set based on the battery temperature Tb of the battery 50 detected by the temperature sensor 51c and the storage ratio SOC of the battery 50, and are input from the battery ECU 52 by communication. . The abnormality determination flag F is a value that is set to 0 during normal times when the motor MG2 can be driven and is set to 1 when there is an abnormality during which the motor MG2 cannot be driven. It should be noted that abnormal times include when the temperature of the motor MG2 and the inverter 42 exceeds a predetermined allowable upper limit temperature, or when the signal from the rotational position detection sensor 44 to the motor ECU 40 is interrupted for a predetermined time. Conceivable.

  When the data is input in this way, a temporary required torque Trtmp is set as a temporary value of the required torque Tr * to be output to the drive shaft 36 based on the input accelerator opening Acc and the vehicle speed V (step S110). Here, in the embodiment, the temporary required torque Trtmp is stored in a ROM (not shown) as a temporary required torque setting map by predetermining a relationship among the accelerator opening Acc, the vehicle speed V, and the temporary required torque Trtmp. When the degree Acc and the vehicle speed V are given, the corresponding temporary required torque Trtmp is derived and set from the stored map. An example of the temporary required torque setting map is shown in FIG.

  Next, the value of the abnormality determination flag F is checked (step S120). When the abnormality determination flag F is 0, that is, in a normal state, the temporary required torque Trtmp is set to the required torque Tr * (step S130), and the rotation speed Nr (the motor MG2 of the motor MG2) is set to the set required torque Tr *. The traveling power Pdrv * required for traveling is calculated by multiplying by the rotational speed Nm2) (step S140).

  Subsequently, based on the storage ratio SOC of the battery 50, a temporary charge / discharge required power Pbtmp is set as a temporary value of the charge / discharge required power Pb * of the battery 50 (a positive value when discharging from the battery 50) (step) S150), as shown in the following equation (1), the set temporary charge / discharge required power Pbtmp is limited by the input / output limits Win and Wout of the battery 50 to set the charge / discharge required power Pb * of the battery 50 (step S160). ). Here, in the embodiment, the temporary charge / discharge required power Pbtmp is stored in a ROM (not shown) as a normal temporary charge / discharge required power setting map by predetermining the relationship between the storage ratio SOC of the battery 50 and the temporary charge / discharge required power Pbtmp. When the storage ratio SOC of the battery 50 is given, the corresponding temporary charge / discharge required power Pbtmp is derived from the stored map and set. An example of the normal temporary charge / discharge required power setting map is shown in FIG. As shown in the figure, the temporary charge / discharge required power Pbtmp is set to a value of 0 when the storage ratio SOC of the battery 50 is a target ratio SOC * (for example, 55%, 60%, 65%, etc.), and the storage ratio SOC is the target. A negative value (a value for charging) is set according to the power storage rate SOC when it is smaller than the rate SOC *, and a positive value (a value for discharging) according to the power storage rate SOC when the power storage rate SOC is larger than the target rate SOC *. ) Is set. The charging / discharging required power Pb * is set by limiting the temporary charging / discharging required power Pbtmp set in this way by the input / output limits Win and Wout of the battery 50, and the battery 50 is charged / discharged by the charging / discharging required power Pb *. Thus, the storage ratio SOC of the battery 50 can be brought close to the target ratio SOC *.

  Pb * = max (min (Pbtmp, Wout), Win) (1)

  When the charge / discharge required power Pb * is set in this manner, as shown in the following equation (2), the set charge / discharge required power Pb * is subtracted from the travel power Pdrv * and the required power Pe as the power to be output from the engine 22 is obtained. * Is calculated (step S170), and the engine 22 is operated based on the required power Pe * and the fuel efficiency operation line defined as the relationship between the rotational speed Ne of the engine 22 and the torque Te for operating the engine 22 efficiently. A target rotational speed Ne * and a target torque Te * as target operating points to be set are set (step S180). FIG. 5 is an explanatory diagram showing an example of the fuel efficiency operation line of the engine 22 and how the target rotational speed Ne * and the target torque Te * are set. In the figure, “Nemin” is the lower limit rotational speed of the fuel efficiency operation line or the high torque operation line described later, and for example, 900 rpm, 1000 rpm, 1100 rpm, or the like can be used. As shown in the figure, the target rotational speed Ne * and the target torque Te * of the engine 22 can be obtained as an intersection of the fuel consumption operation line and a curve with a constant required power Pe * (Ne * × Te *).

  Pe * = Pdrv * -Pb * (2)

  Next, using the target rotational speed Ne * of the engine 22, the rotational speed Nm2 of the motor MG2, 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 target of the motor MG1 is expressed by the following equation (3). Using the calculated target rotational speed Nm1 * of the motor MG1, the input 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 formula (4) is calculated. Thus, a torque command Tm1 * as a torque to be output from the motor MG1 is calculated (step S190). Here, Expression (3) is a dynamic relational expression for the rotating element of the planetary gear 30. FIG. 6 is an explanatory diagram showing an example of a collinear diagram showing a dynamic relationship between the rotational speed and torque of the rotating element of the planetary gear 30 when traveling while outputting power from the engine 22. In the figure, the left S-axis indicates the rotational speed of the sun gear, which is the rotational speed Nm1 of the motor MG1, the C-axis indicates the rotational speed of the carrier, which is the rotational speed Ne of the engine 22, and the R-axis indicates the rotational speed Nm2 of the motor MG2. The rotation speed Nr of the ring gear (drive shaft 36) is shown. Two thick arrows on the R-axis indicate torque (−Tm1 * / ρ) output from the motor MG1 and acting on the drive shaft 36 via the planetary gear 30, and torque output from the motor MG2 to the drive shaft 36. Tm2. In the embodiment, an upward arrow in the figure is a positive torque, and a downward arrow in the figure is a negative torque. Equation (3) can be easily derived from this alignment chart. Further, the equation (4) represents the rotational speed feedback control for causing the rotational speed Nm1 of the motor MG1 to become the target rotational speed Nm1 * (so that the rotational speed Ne of the engine 22 becomes the target rotational speed Ne *). In the equation (4), the first term on the right side is a feedforward term, the second term on the right side is a proportional term of feedback, and the third term on the right side is an integral term of feedback. The first term on the right side is a torque for receiving the torque output from the engine 22 and acting on the sun gear of the planetary gear 30 via the carrier of the crankshaft 26 and the planetary gear 30. Also, “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. When the vehicle travels while outputting power from the engine 22, the motor MG1 outputs torque (negative torque) in a direction that suppresses the increase in the rotational speed Ne of the engine 22, and therefore the rotational speed Nm1 of the motor MG1. Is greater than the value 0, power is generated by the motor MG1, and if the rotational speed Nm1 of the motor MG1 is less than the value 0, power is consumed by the motor MG1.

Nm1 * = Ne * ・ (1 + ρ) / ρ-Nm2 / ρ (3)
Tm1 * =-ρ ・ Te * / (1 + ρ) + k1 ・ (Nm1 * -Nm1) + k2∫ (Nm1 * -Nm1) dt (4)

  When the torque command Tm1 * of the motor MG1 is thus set, as shown in the following equation (5), the motor MG2 is obtained by dividing the torque command Tm1 * of the motor MG1 by the gear ratio ρ of the planetary gear 30 to the required torque Tr *. Is calculated (step S200), and the input / output limits Win and Wout of the battery 50 and the torque of the motor MG1 are calculated as shown in equations (6) and (7). Torque as upper and lower limits of the torque that may be output from the motor MG2 by dividing the difference from the power consumption (generated power) of the motor MG1 obtained by multiplying the command Tm1 * by the rotational speed Nm1 by the rotational speed Nm2 of the motor MG2. Limits Tm2min and Tm2max are calculated (step S210), and the temporary torque Tm2tmp is torque limited as shown in equation (8). M2min, sets the torque command Tm2 * as a torque to be output from the motor MG2 is limited by Tm2max (step S220). Here, equation (5) can be easily derived from the alignment chart of FIG.

Tm2tmp = Tr * + Tm1 * / ρ (5)
Tm2min = (Win-Tm1 * ・ Nm1) / Nm2 (6)
Tm2max = (Wout-Tm1 * ・ Nm1) / Nm2 (7)
Tm2 * = max (min (Tm2tmp, Tm2max), Tm2min) (8)

  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 thus set, the target rotational speed Ne * and the target torque Te * of the engine 22 are transmitted to the engine ECU 24. The torque commands Tm1 * and Tm2 * for the motors MG1 and MG2 are transmitted to the motor ECU 40 (step S230), and this routine is terminated. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * controls the intake air amount so that the engine 22 is operated at an operating point (target operating point) composed of the target rotational speed Ne * and the target torque Te *. Fuel injection control, ignition control, etc. are performed. The motor ECU 40 that receives the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 performs switching control of 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 *. . During normal times when the motor MG2 can be driven, such control allows the engine 22 to be operated efficiently and the required torque Tr * to be driven within the range of the input / output limits Win and Wout of the battery 50 while adjusting the storage ratio SOC of the battery 50. It is possible to travel by outputting to 36.

  Next, the case where the abnormality determination flag F is 1 in step S120, that is, an abnormality will be described. FIG. 7 is an explanatory diagram showing an example of a collinear diagram showing a dynamic relationship between the rotational speed and torque in the rotating element of the planetary gear 30 at the time of abnormality. When the motor MG2 cannot be driven, as shown in the drawing, the engine 22 and the motor MG1 are controlled so that the power from the engine 22 is transmitted to the drive shaft 36 via the planetary gear 30 while the driving of the motor MG2 is stopped. And run. At this time, when the rotational speed Nm1 of the motor MG1 is larger than the value 0, the electric power generated by the motor MG1 is charged in the battery 50, and when the rotational speed Nm1 of the motor MG1 is smaller than the value 0, the discharged power from the battery 50 is When consumed by MG1 and the rotation speed Nm1 of the motor MG1 is 0, the battery 50 is not charged or discharged.

  When the abnormality determination flag F is 1, the vehicle speed-induced torque limit Trmax1 is set based on the vehicle speed V (step S240), and the input limit-induced torque limit Trmax2 is set based on the input limit Win of the battery 50 (step S250). As shown in the following equation (9), the required torque Tr * is set by limiting the temporary required torque Trtmp with the vehicle speed-induced torque limit Trmax1 and the input limit-induced torque limit Trmax2 (step S260).

  Tr * = min (Trtmp, Trmax1, Trmax2) (9)

  Here, in the embodiment, the vehicle speed-induced torque limit Trmax1 is stored in a ROM (not shown) as a vehicle speed-induced torque limit setting map by predetermining the relationship between the vehicle speed V and the vehicle speed-induced torque limit Trmax1. If it is, the corresponding vehicle speed-induced torque limit Trmax1 is derived from the stored map and set. An example of the vehicle speed-induced torque limit setting map is shown in FIG. In the figure, the vehicle speed-induced torque limit Trmax1 is set to a predetermined torque Tr1 when the vehicle speed V is equal to or higher than the predetermined vehicle speed V1, and is larger than the predetermined torque Tr1 when the vehicle speed V is lower than the predetermined vehicle speed V2 smaller than the predetermined vehicle speed V1. The predetermined torque Tr2 is set, and in a region where the vehicle speed V is higher than the predetermined vehicle speed V2 and lower than the predetermined vehicle speed V1, the higher the vehicle speed V is set, the smoother the transition is from the predetermined torque Tr2 toward the predetermined torque Tr1. Here, the predetermined vehicle speed V1 is set to the rotational speed Nr of the drive shaft 36 (hereinafter referred to as the predetermined rotational speed Nr1) at which the rotational speed Nm1 of the motor MG1 is 0 when the rotational speed Ne of the engine 22 is the lower limit rotational speed Nemin. The corresponding vehicle speed V is determined according to the gear ratio ρ of the planetary gear 30 and is, for example, 40 km / h, 45 km / h, 50 km / h, or the like. Further, the predetermined torque Tr1 is obtained by using the upper limit value (predetermined torque Te1 described later) of the engine 22 when the rotational speed Ne of the engine 22 in the high torque operation line described later is the lower limit rotational speed Nemin as the torque of the drive shaft 36. The converted value (Te1 / (1 + ρ)) was used. For example, 20 km / h, 25 km / h, 30 km / h, or the like can be used as the predetermined vehicle speed V2. As the predetermined torque Tr2, a value equal to or lower than a value (Temax / (1 + ρ)) obtained by converting the maximum value Temax of the torque Te of the engine 22 in the high torque operation line into the torque of the drive shaft 36 is used. By setting the required torque Tr * by limiting the temporary required torque Trtmp with the vehicle speed-induced torque limit Trmax1, when the vehicle speed V is less than the predetermined vehicle speed V1, the required torque Tr * becomes closer to the predetermined vehicle speed V1. The upper limit can be made to approach the predetermined torque Tr1 smoothly.

  Further, as shown in the following equation (10), the input limit-induced torque limit Trmax2 is output from the motor MG1 obtained by dividing the input limit Win (<0) of the battery 50 by the rotation speed Nm1 of the motor MG1. The value can be calculated by multiplying the lower limit of the good torque by the value (−1 / ρ) and converting it to the torque of the drive shaft 36. By setting the required torque Tr * by limiting the temporary required torque Trtmp with the input restriction-induced torque limit Trmax2, when charging the battery 50, the battery 50 can be charged with power within the range of the input limit Win. it can. Note that when the rotational speed Nm1 of the motor MG1 is a value 0, the input restriction-induced torque limit Trmax2 cannot be calculated by the equation (10), and when the rotational speed Nm1 of the motor MG1 is a negative value, the input restriction-induced torque limit Trmax2 is negative. Therefore, in the embodiment, when the rotational speed Nm1 of the motor MG1 is 0 or less, the input limit-induced torque limit Trmax2 is not used for setting the required torque Tr *.

  Trmax2 = (Win / Nm1) ・ (-1 / ρ) (10)

  When the required torque Tr * is thus set, the travel power Pdrv * required for travel is calculated by multiplying the set required torque Tr * by the rotational speed Nr of the drive shaft 36 (the rotational speed Nm2 of the motor MG2) (step) S270), the target torque Te * of the engine 22 is calculated by the following equation (11) using the required torque Tr * and the gear ratio ρ of the planetary gear 30 (step S280). Here, the equation (11) is an equation for converting the required torque Tr * into the torque of the crankshaft 26 of the engine 22 and can be easily derived from the alignment chart of FIG.

  Te * = Tr * ・ (1 + ρ) (11)

  When the target torque Te * of the engine 22 is calculated in this way, the high torque operation defined as the relationship between the calculated target torque Te * of the engine 22 and the rotational speed Ne of the engine 22 on the higher torque side than the fuel consumption operation line and the torque Te. Based on the line, a temporary rotational speed Netmp is set as a temporary value of the target rotational speed Ne * of the engine 22 (step S290). FIG. 9 is an explanatory diagram showing an example of a high torque operation line of the engine 22 and how the temporary rotation speed Netmp is set. In FIG. 9, the fuel consumption operation line is indicated by a one-dot chain line for reference. In the figure, as described above, “Te1” represents the predetermined torque Tr1 (torque set to the vehicle speed-induced torque limit Trmax1 when the vehicle speed V is equal to or higher than the predetermined vehicle speed V1) in FIG. Torque converted to torque. As shown in the figure, the temporary rotational speed Netmp of the engine 22 can be obtained as an intersection of the target torque Te * of the engine 22 and the high torque operation line. By using the high torque operation line instead of the fuel consumption operation line, it is possible to cope with a case where the required torque Tr * is large (the provisional rotational speed Netmp on the high torque operation line can be set). Hereinafter, an operation point composed of the temporary rotational speed Netmp and the target torque Te * is referred to as a high torque restricted operation point.

  Then, as shown in the following equation (12), it is estimated that the engine 22 is output when the engine 22 is operated at a high torque restricted operation point by multiplying the temporary rotational speed Netmp of the engine 22 by the target torque Te *. Is calculated (step S300), and the calculated estimated output power Peest is subtracted from the traveling power Pdrv * as shown in the equation (13), so that the engine 22 is operated at a high torque restricted operation point. The estimated charge / discharge power Pbest (the positive value when discharging from the battery 50) is calculated as the power estimated to be charged / discharged when the battery 50 is operated (step S310).

Peest = Netmp ・ Te * (12)
Pbest = Pdrv * -Peest (13)

  Next, temporary charge / discharge required power Pbtmp is set based on the storage ratio SOC of the battery 50 (step S320). In this case, the temporary charging / discharging request power Pbtmp is stored in a ROM (not shown) as a map for setting the abnormal charging / discharging request power by predetermining the relationship between the storage ratio SOC of the battery 50 and the temporary charging / discharging request power Pbtmp in the embodiment. In addition, when the storage ratio SOC of the battery 50 is given, the corresponding temporary charge / discharge required power Pbtmp is derived and set from the stored map. An example of the temporary charge / discharge required power setting map is shown in FIG. In FIG. 10, a normal temporary charge / discharge required power setting map (a relationship between the normal storage ratio SOC and the temporary charge / discharge required power Pbtmp) is indicated by a one-dot chain line for reference. In this case, the temporary charge / discharge required power Pbtmp is, as illustrated, from a predetermined ratio S1 to a predetermined ratio S2 in which the storage ratio SOC of the battery 50 includes a target ratio SOC * (for example, 55%, 60%, 65%, etc.). When the power storage ratio SOC is smaller than the predetermined ratio S1, a negative value (value for charging) is set according to the power storage ratio SOC, and when the power storage ratio SOC is larger than the predetermined ratio S2. A positive value (discharge value) is set according to the storage ratio SOC. Here, the predetermined ratio S1 can use a value such as 5%, 10%, or 15% smaller than the target ratio SOC *, and the predetermined ratio S2 can be larger than the target ratio SOC * such as 5%, 10%, or 15%. A value can be used. The predetermined ratio S1 or the predetermined ratio S2 may be the same value as the target ratio SOC *. As described above, the reason why the value 0 is set as the dead zone in the temporary charge / discharge required power Pbtmp in the range from the predetermined ratio S1 to the predetermined ratio S2 in the case of an abnormality is as follows. At the time of abnormality, when the rotational speed Nm1 of the motor MG1 is larger than the value 0, the motor MG1 generates power and charges the battery 50. When the rotational speed Nm1 of the motor MG1 is smaller than the value 0, the battery 50 is discharged and discharged by the motor MG1. Electric power will be consumed. For this reason, the battery 50 is likely to be overcharged or overdischarged due to the continuation of charging or discharging of the battery 50. Therefore, in the embodiment, in order to suppress the occurrence of such inconvenience, a dead zone is provided.

  Next, as shown in the following equation (14), the smaller one of the estimated charge / discharge power Pbest and the temporary charge / discharge required power Pbtmp of the battery 50 is limited by the input / output limits Win and Wout of the battery 50 to The required charge / discharge power Pb * is set (step S330), and the required power Pe * is calculated by subtracting the set charge / discharge required power Pb * of the battery 50 from the travel power Pdrv * as shown in the following equation (15). (Step S340).

Pb * = max (min (min (Pbest, Pbtmp), Wout), Win) (14)
Pe * = Pdrv * -Pb * (15)
Ne * = Pe * / Te * (16)

  Then, as shown in equation (16), the calculated required power Pe * is divided by the target torque Te * of the engine 22 to calculate the target rotational speed Ne * of the engine 22 (step S350). Similar to the processing, the torque command Tm1 * of the motor MG1 is set (step S360), and the target rotational speed Ne * and target torque Te * of the engine 22 are sent to the engine ECU 24, the torque command Tm1 * of the motor MG1 and the inverter 42 ( A gate cutoff command of an inverter for driving the motor MG2 is transmitted to the motor ECU 40 (step S370), and this routine is finished. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * controls the intake air amount so that the engine 22 is operated at an operating point (target operating point) composed of the target rotational speed Ne * and the target torque Te *. Fuel injection control, ignition control, etc. are performed. The motor ECU 40 that has received the torque command Tm1 * of the motor MG1 and the gate cutoff command of the inverter 42 performs switching control of the switching element of the inverter 41 driven by the torque command Tm1 * of the motor MG1 and gates the inverter 42 ( All switching elements are turned off).

  Here, when the motor MG2 cannot be driven, the rotational speed Nr of the drive shaft 36 is less than the predetermined rotational speed Nr1 (the vehicle speed V is the predetermined vehicle speed V1). An operation at an abnormally high vehicle speed when the rotational speed Nr1 is an abnormal predetermined vehicle speed and the rotational speed Nr of the drive shaft 36 is larger than the predetermined rotational speed Nr1 at the abnormal time will be described. For simplicity, when the estimated charge / discharge power Pbest and the temporary charge / discharge required power Pbtmp of the battery 50 are both within the input / output limits Win and Wout of the battery 50 (the estimated charge / discharge power Pbest or the temporary charge / discharge required power). (When Pbtmp is set to the charge / discharge required power Pb * as it is), description will be given.

  First, the contents common to the abnormal low vehicle speed, the abnormal predetermined vehicle speed, and the abnormal high vehicle speed will be described. FIG. 11 is an explanatory diagram showing operation points of the engine 22 at the time of abnormality. When an abnormality occurs, first, a target torque Te * in which a torque obtained by converting the required torque Tr * into a torque of the crankshaft 26 of the engine 22 (hereinafter referred to as an output shaft equivalent torque), a target torque Te *, and a high torque operation line are set. And a high torque restricted operation point (refer to point A in the figure) consisting of the temporary rotational speed Netmp in which the rotational speed at the intersection with is set. Then, the estimated charge / discharge power Pbest of the battery 50 when the engine 22 is operated at the high torque restricted operation point is compared with the temporary charge / discharge required power Pbtmp based on the storage ratio SOC of the battery 50. When the estimated temporary charging / discharging power Pbest is equal to or less than the temporary charging / discharging required power Pbtmp, the estimated charging / discharging power Pbest is set to the charging / discharging required power Pb *, so that it can be understood by arranging the above formulas (12) to (16). In addition, the temporary rotational speed Netmp and the target rotational speed Ne * are equal. Therefore, the required torque Tr * (travel power Pdrv *) is output to the drive shaft 36 while the engine 22 is operated at the high torque restricted operation point. On the other hand, when the temporary charge / discharge required power Pbtmp is less than the estimated charge / discharge power Pbest, the temporary charge / discharge required power Pbtmp is set to the charge / discharge required power Pb *, so that the required power Pe * becomes larger than the estimated output power Pest, The rotational speed Ne * is larger than the temporary rotational speed Netmp. Therefore, the required torque Tr * (running) while operating the engine 22 at the storage ratio-derived operation point (refer to point B in the figure) that is the same torque Te as the high torque restricted operation point and that is the operation point on the high speed side The power Pdrv *) is output to the drive shaft 36 for traveling. In both cases, the torque from the engine 22 can be increased as compared with the case where the engine 22 is operated independently (operating so that the difference between the target rotational speed Ne * and the current rotational speed Ne is canceled). Further, stalling of the engine 22 can be further suppressed when the torque from the motor MG1 becomes small (in the direction in which the rotational speed Ne of the engine 22 is pressed down (in the negative direction)). As described above, when the vehicle speed V is equal to or higher than the predetermined vehicle speed V1 (at an abnormal predetermined vehicle speed or an abnormally high vehicle speed), the required torque Tr * is equal to or lower than the predetermined torque Tr1, and the target torque Te * of the engine 22 is predetermined. Since the torque becomes equal to or less than Te1, the temporary rotational speed Netmp of the engine 22 becomes the lower limit rotational speed Nemin. That is, the high torque restricted operation point is an operation point including the lower limit rotation speed Nemin and the output shaft converted torque.

  Next, each of an abnormally low vehicle speed, an abnormally predetermined vehicle speed, and an abnormally high vehicle speed will be described. First, the abnormal low vehicle speed will be described. FIG. 12 is an explanatory diagram showing an example of a collinear diagram showing the relationship between the rotational speeds of the rotating elements of the planetary gear 30 at an abnormally low vehicle speed. At an abnormally low vehicle speed, as shown by the solid line in FIG. 12, when the engine 22 is operated at a high torque restricted operation point, the rotational speed Nm1 of the motor MG1 becomes a positive value, so the estimated output power Pest of the engine 22 is the driving power. It becomes larger than Pdrv *, and the estimated charge / discharge power Pbest of the battery 50 becomes a negative value. When the estimated charging / discharging power Pbest is equal to or less than the temporary charging / discharging required power Pbtmp, as shown by the solid line in FIG. 12, the engine 22 is operated at a high torque restricted operating point and the motor MG1 is driven at a positive rotational speed (power generation is performed). ), The required torque Tr * (travel power Pdrv *) is output to the drive shaft 36 to travel, so the rotational speed Ne of the engine 22 can be made relatively small. In this case, the battery 50 is charged with electric power corresponding to the estimated charge / discharge power Pbest. On the other hand, when the temporary charge / discharge required power Pbtmp is less than the estimated charge / discharge power Pbest, as shown by the broken line in FIG. 12, the engine 22 is operated at the storage ratio-derived operation point and the motor MG1 is driven at a positive rotational speed ( Since the required torque Tr * (traveling power Pdrv *) is output to the drive shaft 36 while traveling, the power corresponding to the temporary charging / discharging required power Pbtmp (on the charging side from the estimated charging / discharging power Pbest) The battery 50 can be charged with a large electric power) to increase the storage ratio SOC of the battery 50.

  At this abnormally low vehicle speed, the required torque Tr * is set within a range equal to or less than the vehicle speed-induced torque limit Trmax1 that tends to approach the predetermined torque T1 more smoothly as the vehicle speed V approaches the predetermined vehicle speed V1. The upper limit of Te * is that the vehicle speed V approaches the predetermined torque Te1 more smoothly as the vehicle speed V approaches the predetermined vehicle speed V1. Therefore, when the required torque Tr * is limited by the vehicle speed-induced torque limit Trmax1 (both are equal) and the estimated charge / discharge power Pbest is less than or equal to the temporary charge / discharge required power Pbtmp (for example, the temporary charge / discharge required power Pbtmp is greater than or equal to 0) When the vehicle speed V becomes higher than the predetermined vehicle speed V1, the high-torque restricted operation point smoothly shifts to the lower limit rotation speed Nemin side as the vehicle speed V approaches the predetermined vehicle speed V1. Can be discharged. In other words, when the target rotational speed Ne * of the engine 22 is higher than the temporary rotational speed Netmp (the rotational speed in the high torque operation line) because the temporary charge / discharge required power Pbtmp is smaller than the estimated charge / discharge power Pbest, the vehicle speed V is the predetermined vehicle speed. Even when V1 is reached, the rotational speed Nm1 of the motor MG1 becomes a positive value, and the battery 50 is charged.

  The abnormal predetermined vehicle speed will be described. FIG. 13 is an explanatory diagram showing an example of a collinear diagram showing the relationship between the rotational speeds of the rotating elements of the planetary gear 30 at the abnormal predetermined vehicle speed. At the abnormal predetermined vehicle speed, as shown by the solid line in FIG. 13, when the engine 22 is operated at a high torque restricted operation point, the rotational speed Nm1 of the motor MG1 becomes 0, so the estimated output power Pest of the engine 22 and the traveling power Pdrv * Becomes equal, and the estimated charge / discharge power Pbest of the battery 50 is 0. When the estimated charging / discharging power Pbest is equal to or less than the temporary charging / discharging required power Pbtmp (when the temporary charging / discharging required power Pbtmp is equal to or greater than 0), as shown by the solid line in FIG. While driving and driving the motor MG1 at a rotational speed of 0, the required torque Tr * (traveling power Pdrv *) is output to the drive shaft 36 to travel, so that the rotational speed Ne of the engine 22 is relatively low. Can be small. In this case, the battery 50 is not charged / discharged. On the other hand, when the temporary charge / discharge required power Pbtmp is less than the estimated charge / discharge power Pbest (when the temporary charge / discharge required power Pbtmp is a negative value), as shown by the broken line in FIG. 22 and the motor MG1 is driven at a positive rotational speed (power generation is performed) while the required torque Tr * (travel power Pdrv *) is output to the drive shaft 36 to travel. When the storage ratio SOC is low, the battery 50 can be charged with power corresponding to the temporary charge / discharge required power Pbtmp to increase the storage ratio SOC of the battery 50.

  A description will be given of an abnormally high vehicle speed. FIG. 14 is an explanatory diagram showing an example of a collinear diagram showing the relationship between the rotational speeds of the rotating elements of the planetary gear 30 at an abnormally high vehicle speed. At an abnormally high vehicle speed, as shown by the solid line in FIG. 14, when the engine 22 is operated at a high torque restricted operation point, the rotational speed Nm1 of the motor MG1 becomes a negative value, and therefore the estimated output power Pest of the engine 22 is for traveling. It becomes smaller than the power Pdrv *, and the estimated charge / discharge power Pbest of the battery 50 becomes a positive value. When the estimated charge / discharge power Pbest is less than or equal to the temporary charge / discharge required power Pbtmp (when both the estimated charge / discharge power Pbest and the temporary charge / discharge required power Pbtmp are positive), as shown by the solid line in FIG. The engine 22 is operated at the operating point and the motor MG1 is driven at a negative rotational speed (consuming power) while the required torque Tr * (travel power Pdrv *) is output to the drive shaft 36 to travel. . In this case, power is discharged from the battery 50. On the other hand, when the temporary charging / discharging required power Pbtmp is smaller than the estimated charging / discharging power Pbest and the temporary charging / discharging required power Pbtmp is a positive value, the engine 22 is operated at the storage ratio-derived operating point as shown by the broken line in FIG. At the same time, while driving the motor MG1 at a negative rotational speed (consuming power), the required torque Tr * (travel power Pdrv *) is output to the drive shaft 36 to travel. Further, when the temporary charge / discharge required power Pbtmp is smaller than the estimated charge / discharge power Pbest and the temporary charge / discharge required power Pbtmp is 0, the engine 22 is operated at the power storage ratio-derived operation point as shown by a one-dot chain line in FIG. At the same time, while driving the motor MG1 at a rotation speed of 0, the required torque Tr * (travel power Pdrv *) is output to the drive shaft 36 to travel. In this case, the battery 50 is not charged / discharged. At the time of abnormality, the battery 50 is charged when the rotational speed Nm1 of the motor MG1 is a positive value, and is discharged from the battery 50 when the rotational speed Nm1 of the motor MG1 is a negative value. The battery 50 is likely to be overcharged or overdischarged. In the embodiment, the battery 50 is overcharged or overdischarged by suppressing charging / discharging of the battery 50 by setting a range of the power storage rate SOC from the predetermined rate S1 to the predetermined rate S2 as a dead zone. Can be suppressed. Further, when the temporary charge / discharge required power Pbtmp is smaller than the estimated charge / discharge power Pbest and the temporary charge / discharge required power Pbtmp is a negative value, as shown by a two-dot chain line in FIG. And the required torque Tr * (travel power Pdrv *) is output to the drive shaft 36 while the motor MG1 is driven at a positive rotational speed. Thereby, when the storage ratio SOC of the battery 50 is low, the battery 50 can be charged with electric power corresponding to the temporary charge / discharge required power Pbtmp to increase the storage ratio SOC of the battery 50.

  In the embodiment, the planetary gear 30 and the motors MG1, MG2, and the motor MG1, MG2, are set for the sake of simplicity in setting the required power Pe * of the engine 22 (see steps S170 and S340) and setting the estimated charge / discharge power Pbest (see step S310). Although it has been described that it is performed without considering the loss of the battery 50 or the like, the power consumption of a power device (not shown) connected to the power line connecting the inverters 41 and 42 and the battery 50, actually, these are considered. It is preferable to do so.

  According to the hybrid vehicle 20 of the embodiment described above, when the motor MG2 cannot be driven, the output shaft converted by converting the required torque Tr * based on the temporary required torque Trtmp of the drive shaft 36 into the torque of the crankshaft 26 of the engine 22. A high torque constraint comprising a target torque Te * for which torque is set, and a temporary rotational speed Netmp in which the rotational speed at the intersection of the target torque Te * and the high torque operation line on the higher torque side than the fuel consumption operation line is set Since the engine 22 and the motor MG1 are controlled so that the engine 22 is operated at the operation point and the required torque Tr * is output to the drive shaft 36, the torque from the engine 22 is compared with that in which the engine 22 operates independently. When the torque from the motor MG1 changes, the engine 22 It can be further suppressed to Le.

  Further, according to the hybrid vehicle 20 of the embodiment, when the abnormality occurs, the battery 50 is charged / discharged when the temporary charge / discharge required power Pbtmp based on the storage ratio SOC of the battery 50 operates the engine 22 at the high torque restricted operation point. When the estimated charge / discharge power Pbest is estimated to be smaller than the estimated charge / discharge power Pbest, a required power Pe * obtained by subtracting the charge / discharge required power Pb * based on the temporary charge / discharge required power Pbtmp from the travel power Pdrv * is calculated. The target rotational speed Ne * is calculated by dividing the required power Pe * by the target torque Te * to which the output shaft conversion torque is set, and the engine is operated at the operating point consisting of the calculated target rotational speed Ne * and the target torque Te *. 22 is operated, and the required torque Tr * is controlled to be output to the drive shaft 36. It is possible to increase the state of charge SOC of the battery 50 to charge the battery 50 with electric power based on btmp.

  Furthermore, according to the hybrid vehicle 20 of the embodiment, in the event of an abnormality, a temporary charge / discharge request is made based on the storage ratio SOC of the battery 50 with the range from the predetermined ratio S1 including the target ratio SOC * to the predetermined ratio S2 being a dead zone of value 0. Since the power Pbtmp is set, when the estimated charge / discharge power Pbest is 0 or more, the battery 50 can be prevented from being frequently charged / discharged.

  In addition, according to the hybrid vehicle 20 of the embodiment, when the vehicle speed V is equal to or lower than the predetermined vehicle speed V1 at the time of abnormality, the vehicle speed V is less than the vehicle speed-induced torque limit Trmax1 that tends to approach the predetermined torque T1 smoothly as the vehicle speed V approaches the predetermined vehicle speed V1. Therefore, when the required torque Tr * is limited by the vehicle speed-induced torque limit Trmax1 and the estimated charge / discharge power Pbest is equal to or less than the temporary charge / discharge required power Pbtmp, the high torque restricted operation point is As the vehicle speed V approaches the predetermined vehicle speed V1, the transition to the lower limit rotational speed Nemin is smoothly performed, and the battery 50 can be discharged when the vehicle speed V becomes higher than the predetermined vehicle speed V1.

  In the hybrid vehicle 20 of the embodiment, when the motor MG2 cannot be driven, the temporary required torque Trtmp based on the accelerator opening Acc and the vehicle speed V is input based on the vehicle speed-induced torque limit Trmax1 based on the vehicle speed V and the input limit Win of the battery 50. Although the required torque Tr * is set by being limited by the restriction-induced torque limit Trmax2, the temporary required torque Trtmp is limited by only one of the vehicle speed-induced torque limit Trmax1 and the input limit-induced torque limit Trmax2. Tr * may be set, or the temporary required torque Trtmp may be set as the required torque Tr * as it is.

  In the hybrid vehicle 20 of the embodiment, when the motor MG2 cannot be driven, the target torque Te * of the engine 22 (the output shaft equivalent torque obtained by converting the required torque Tr * into the torque of the crankshaft 26 of the engine 22) and the high torque operation line. The estimated charge / discharge power Pbest as the difference between the estimated output power Pest from the engine 22 and the traveling power Pdrv * when the engine 22 is operated at the high torque restricted operation point at the intersection with the battery 50 and the storage ratio SOC of the battery 50 The charging / discharging required power Pb * of the battery 50 is set by limiting the temporary charging / discharging required power Pbtmp resulting from the larger value on the charging side of the battery 50 by the input / output limits Win and Wout of the battery 50. The engine is obtained by subtracting the charge / discharge required power Pb * from the driving power Pdrv *. The required power Pe * of 2 is set, and the required power Pe * is divided by the target torque Te * to set the target rotational speed Ne * of the engine 22. However, regardless of the temporary charge / discharge required power Pbtmp ( The estimated charge / discharge power Pbest is limited by the input / output limits Win and Wout of the battery 50 to set the charge / discharge request power Pb * without using the temporary charge / discharge request power Pbtmp. The target rotational speed Ne * may be set by dividing the required power Pe * obtained by subtracting from the power Pdrv * for use by the target torque Te *. In this case, if the temporary estimated charge / discharge power Pbest is within the range of the input / output limits Win and Wout of the battery 50, the engine 22 is operated at the high torque restricted operation point regardless of the temporary charge / discharge required power Pbtmp. become.

  In the hybrid vehicle 20 of the embodiment, when the motor MG2 cannot be driven, a range from the predetermined ratio S1 including the target ratio SOC * to the predetermined ratio S2 is set as a dead band for setting the value 0 to the temporary charge / discharge request power Pbtmp. Temporary charge / discharge required power Pbtmp is set based on the storage ratio SOC and the normal charge / discharge required power Pbtmp is set based on the storage ratio SOC of the battery 50 without providing a dead zone in normal times when the motor MG2 can be driven. However, at the time of abnormality, the provisional charge / discharge required power Pbtmp may be set based on the storage ratio SOC of the battery 50 in the same manner as in the normal time without providing a dead zone. Further, the normal charge / discharge required power Pbtmp may be set based on the storage ratio SOC of the battery 50 by providing a dead zone that is narrower than that at the time of abnormality or the same dead zone as that at the time of abnormality.

  In the hybrid vehicle 20 of the embodiment, the power from the motor MG2 is output to the drive shaft 36. However, as illustrated in the hybrid vehicle 120 of the modified example of FIG. 15, the drive shaft 36 transmits the power from the motor MG2. It may be output to an axle (an axle connected to the wheels 39a and 39b in FIG. 15) different from the connected axle (the axle to which the drive wheels 38a and 38b are connected).

  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”, the HVECU 70 that executes the drive control routine of FIG. 2, the engine ECU 24 that receives the required power Pe * and the target rotational speed Ne * of the engine 22 from the HVECU 70, and the HVECU 70 A motor ECU 40 that receives torque commands Tm1 * and Tm2 * of motors MG1 and MG2 and controls motors MG1 and MG2 and receives a gate cutoff command of inverter 42 from HVECU 70 and gates inverter 42 The thing corresponds to “control means”.

  Here, the “engine” is not limited to the engine 22 that outputs power using gasoline or light oil as a fuel, and may be any type of engine. The “first motor” is not limited to the motor MG1 configured as a synchronous generator motor, and may be any type of motor. The “planetary gear” is not limited to the planetary gear 30 (single pinion type planetary gear), but includes a drive shaft connected to the axle, such as a double pinion type planetary gear or a combination of a plurality of planetary gears. Any type of planetary gear may be used as long as three rotating elements are connected to the output shaft of the engine and the rotating shaft of the first motor. The “second motor” is not limited to the motor MG2 configured as a synchronous generator motor, and may be any type of motor as long as it can input and output power to the drive shaft. The “battery” is not limited to the battery 50 configured as a lithium ion secondary battery, and the first motor, the second motor, and the electric power such as a nickel hydride secondary battery, a nickel cadmium secondary battery, and a lead storage battery. Any type of battery may be used as long as the exchange is possible. The “control means” is not limited to the combination of the HVECU 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”, at the normal time when the motor MG2 can be driven, the travel power Pdrv * is obtained by multiplying the required torque Tr * set with the temporary required torque Trtmp of the drive shaft 36 by the rotational speed Nr of the drive shaft 36. The required power Pe * is calculated by subtracting the temporary charge / discharge required power Pbtmp based on the storage ratio SOC of the battery 50 from the travel power Pdrv *, and the intersection of the calculated required power Pe * and the fuel consumption operation line is determined as the engine 22. Is set as a target rotational speed Ne * and a target torque Te *, and the engine 22 is operated at an operating point consisting of the set target rotational speed Ne * and the target torque Te *, and the required torque Tr * is output to the drive shaft 36. When the engine 22 and the motors MG1 and MG2 are controlled so that the motor MG2 cannot be driven, it is necessary to use the drive shaft 36 temporarily. The target torque Te * in which the output shaft equivalent torque obtained by converting the required torque Tr * based on the torque Trtmp into the torque of the crankshaft 26 of the engine 22 is set, and the target torque Te * and the high torque on the higher torque side than the fuel consumption operation line The engine 22 and the motor MG1 are operated so that the engine 22 is operated at an operation point consisting of the temporary rotation speed Netmp in which the rotation speed at the intersection with the operation line is set, and the required torque Tr * is output to the drive shaft 36. It is not limited to what is controlled, but the power for driving is set as the product of the required torque of the drive shaft and the rotational speed of the drive shaft, and the charge ratio is the charge / discharge request power of the battery based on the charge ratio of the battery The required power of the engine is set based on the power and driving power, and the required power of the engine and the engine speed And the engine, the first motor and the second motor are controlled such that the engine is operated at the first operation point based on the first constraint of the torque and the required torque is output to the drive shaft, and the second motor cannot be driven. At the time of abnormality, the output shaft conversion torque obtained by converting the required torque of the drive shaft into the torque of the output shaft of the engine, and the rotation speed based on the output shaft conversion torque and the second constraint on the higher torque side than the first constraint. Any engine may be used as long as it controls the engine and the first motor so that the engine is operated at two operation points and the required torque is output to the drive shaft.

  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), 26 crankshaft, 30 planetary gear, 36 drive shaft, 37 differential gear, 38a, 38b drive wheel, 39a, 39b wheel, 40 motor electronics 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), 70 hybrid electronics Control unit (HVECU), 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 6 brake pedal position sensor, 88 vehicle speed sensor, MG1, MG2 motor.

Claims (4)

An engine, a first motor, a drive shaft connected to an axle, a planetary gear in which three rotation elements are connected to an output shaft of the engine and a rotation shaft of the first motor, and a rotation shaft connected to the drive shaft A hybrid vehicle comprising: the second motor, and a battery capable of exchanging electric power with the first motor and the second motor,
A power for traveling is set as a product of the required torque of the drive shaft and the rotational speed of the drive shaft, and the charge due to charge ratio of the battery based on the charge ratio of the battery and the power for running And the engine is operated at a first operating point based on the engine required power and a first constraint on the engine speed and torque, and the requested torque is driven by the engine. Control means for controlling the engine, the first motor and the second motor to be output to a shaft;
The control means is configured so that when the second motor cannot be driven ,
The output shaft conversion torque obtained by converting the required torque of the drive shaft into the torque of the output shaft of the engine, and the rotation speed based on the output shaft conversion torque and the second constraint on the higher torque side than the first constraint. Estimated charging / discharging that the battery is charged / discharged when the engine and the first motor are controlled such that the engine is operated at the second operating point and the required torque is output to the drive shaft. The engine is operated at the second operating point and the requested torque is output to the drive shaft when the power due to the storage ratio is not large on the charging side of the battery as compared with power. And the first motor,
When the power storage ratio-derived power is larger on the charging side of the battery than the estimated charge / discharge power, the required power of the engine based on the output shaft equivalent torque, the power storage ratio-derived power and the driving power is The engine and the first motor are operated such that the engine is operated at a third operating point that is obtained by dividing by the output shaft converted torque and the required torque is output to the drive shaft. Is a means to control,
Hybrid car. The hybrid vehicle according to claim 1 ,
The power due to the power storage ratio is a power that is set based on the power storage ratio when the abnormality occurs, with a predetermined range of the power storage ratio of the battery as a dead zone.
Hybrid car. A hybrid vehicle according to claim 1 or 2 ,
The control means sets the temporary required torque corresponding to the accelerator operation amount to the required torque when the abnormality is not occurring, and sets the temporary required torque according to the vehicle speed to the first torque limit and the battery allowance when abnormal. A means for setting the required torque by limiting at least one of the second torque limits according to the input power;
Hybrid car. A hybrid vehicle according to claim 3 ,
The first torque limit is set such that the vehicle speed tends to decrease as the vehicle speed approaches the reference vehicle speed at or below a reference vehicle speed at which the rotation speed of the first motor is zero when the engine rotation speed is the lower limit rotation speed. Limit,
The second torque limit is a torque limit obtained by converting the allowable power generation torque of the first motor obtained by dividing the allowable input power of the battery by the rotation speed of the first motor into the torque of the drive shaft. is there,
Hybrid car.

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