JP6024507B2 - Hybrid car - Google Patents

Description

  The present invention relates to a hybrid vehicle. More specifically, the present invention relates to an engine capable of outputting driving power, a motor capable of inputting / outputting power to / from the engine output shaft, and an operating point where the engine includes a target rotational speed and a target torque. The present invention relates to an automobile including control means for controlling an engine and a motor so as to travel with driving torque while being driven.

  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. When the engine is loaded, the torque difference obtained by subtracting the output torque from the engine target torque is greater than or equal to the heavy determination torque difference. Sometimes, it is determined that the fuel of the engine is heavy and correction is made to increase the fuel injection amount (see, for example, Patent Document 1).

JP 2010-255493 A

  In the above-described hybrid vehicle, a predetermined value (a uniform value) is used as the heavy determination torque difference. Therefore, depending on the operating state of the engine, it is erroneously determined that the fuel is heavy, and the fuel injection amount is unnecessary. In some cases, such as an increase correction is performed, or the fuel injection amount increase correction is not performed because the fuel cannot be determined even though the fuel is heavy.

  The main purpose of the hybrid vehicle of the present invention is to determine more accurately whether the fuel of the engine is heavy.

  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 capable of outputting power for traveling, a motor capable of inputting / outputting power to / from the output shaft of the engine, and the engine travels with traveling torque while being operated at an operating point including a target rotational speed and a target torque. A hybrid vehicle comprising control means for controlling the engine and the motor,
The control means compares the torque difference, which is the difference between the target torque and the output torque, with a torque difference threshold that tends to increase as the target torque increases, and determines whether the fuel of the engine is heavy. Is a means of judging,
It is characterized by that.

  In the hybrid vehicle of the present invention, whether the engine fuel is heavy or not is compared with a torque difference threshold that tends to increase as the target torque increases, which is the difference between the target torque and the output torque of the engine. Determine whether. Generally, when the engine fuel is heavy, the larger the target torque of the engine, the easier the output torque becomes smaller than the target torque (the torque difference tends to increase). Therefore, by using the torque difference threshold value corresponding to the target torque, it can be determined more accurately whether or not the engine fuel is heavy. Here, the output torque of the engine may be estimated based on the torque output from the motor.

  In such a hybrid vehicle of the present invention, the control means determines that the engine fuel is heavy when a counter that is incremented when the torque difference is greater than or equal to the torque difference threshold is greater than or equal to a predetermined value. Or a means for determining that the engine fuel is heavy when a state where the torque difference is equal to or greater than the torque difference threshold value continues for a predetermined time. It can also be.

  In the hybrid vehicle of the present invention, the control means is means for determining whether or not the engine fuel is heavy when a change amount per unit time of the target torque is larger than a change amount threshold value. Can also be. This is because when the target torque of the engine changes, such as when the vehicle is accelerating or decelerating, the engine response delay affects the torque difference, so there is a possibility of erroneous determination as to whether or not the engine fuel is heavy. Based on the reason that there is.

  Furthermore, in the hybrid vehicle of the present invention in which it is not determined whether or not the engine fuel is heavy when the amount of change in the target torque of the engine per unit time is equal to or greater than the change amount threshold, the control means includes the target And a means for comparing the torque difference with the torque difference threshold when a second counter that is incremented when the amount of change in torque per unit time is less than or equal to the change threshold is greater than or equal to a second predetermined value. Or means for comparing the torque difference with the torque difference threshold when the amount of change in the target torque per unit time is equal to or less than the change threshold for a second predetermined time. There can be.

  In addition, in the hybrid vehicle of the present invention, a planetary gear in which three rotating elements are connected to a rotating shaft coupled to an axle, an output shaft of the engine, and a rotating shaft of the generator, and a rotor on the drive shaft. And a connected second motor.

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 fuel heavy determination routine performed by HVECU70 of an Example. It is explanatory drawing which shows an example of the collinear diagram which shows the dynamic relationship between the rotation speed and torque in the rotation element of the planetary gear 30 when drive | working by engine operation mode. It is explanatory drawing which shows an example of the map for torque difference threshold value setting. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 120 according to a modification. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 220 of a modified example. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 320 of a modified example.

  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 according to the embodiment includes an engine 22 that outputs power by receiving fuel such as gasoline and light oil from a fuel tank 21, and an engine electronic control unit (hereinafter referred to as an engine control unit) that controls the drive of the engine 22. An engine ECU) 24, a planetary gear 30 having a carrier connected to the crankshaft 26 of the engine 22 and a ring gear connected to a drive shaft 36 connected to drive wheels 38a, 38b via a differential gear 37; A motor MG1, which is configured as a synchronous generator motor and whose rotor is connected to the sun gear of the planetary gear 30, for example, a motor MG2 which is configured as a synchronous generator motor and whose rotor is connected to the drive shaft 36, and drives the motors MG1, MG2 Inverters 41 and 42 and inverter 41 An electronic control unit for motor (hereinafter referred to as a motor ECU) 40 that drives and controls the motors MG1 and MG2 by switching control of switching elements (not shown) 42, and inverters 41 and 42, for example, configured as a lithium ion secondary battery. A battery 50 that exchanges electric power with the motors MG1 and MG2, via a battery electronic control unit (hereinafter referred to as battery ECU) 52 that manages the battery 50, and a hybrid electronic control unit (hereinafter referred to as HVECU) that controls the entire vehicle. 70).

  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 opening TH 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 Attached to 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. The engine ECU 24 performs various operations for driving the engine 22. Control signal, for example, a drive signal to the fuel injection valve, a drive signal to the throttle motor that adjusts the position of the throttle valve, a control signal to the ignition coil integrated with the igniter, and a variable that can change the opening / closing timing of the intake valve A control signal or the like to the 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. The torque conversion operation mode and the charge / discharge operation mode are modes in which the engine 22, the motor MG1, and the motor MG2 are controlled so that the required power is output to the drive shaft 36 with the operation of the engine 22. Since there is no substantial difference in control, both are hereinafter referred to as the engine operation mode.

  In the engine operation mode, the HVECU 70 generates a required torque Tr * required for traveling (to be output to the drive shaft 36) based on the accelerator opening Acc from the accelerator pedal position sensor 84 and the vehicle speed V from the vehicle speed sensor 88. Set for the required torque Tr * and set the required torque Tr * by the number of revolutions Nr of the drive shaft 36 (for example, the number of revolutions Nm2 of the motor MG2 or the number of revolutions obtained by multiplying the vehicle speed V by a conversion factor). Calculate the power Pdrv *, and request the vehicle by subtracting the charge / discharge required power Pb * (positive value when discharging from the battery 50) based on the storage ratio SOC of the battery 50 from the calculated driving power Pdrv *. The required power Pe * (to be output from the engine 22) is set. Then, the target rotational speed Ne of the engine 22 is obtained using an operation line (for example, a fuel efficiency optimal operation line) as a relationship between the rotational speed Ne of the engine 22 and the torque Te that can efficiently output the required power Pe * from the engine 22. * And target torque Te * are set, and the motor is controlled by rotation speed feedback control so that the rotation speed Ne of the engine 22 becomes the target rotation speed Ne * within the range of the input / output limits Win and Wout of the battery 50. The torque command Tm2 * of the motor MG2 is reduced by setting the torque command Tm1 * of the MG1 and subtracting the torque acting on the drive shaft 36 via the planetary gear 30 from the required torque Tr * when the motor MG1 is driven by the torque command Tm1 *. The engine ECU 24 sets the set target rotational speed Ne * and the target torque Te *. Transmitted, the torque command Tm1 *, the Tm2 * is sent to the motor ECU 40. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te *, controls the intake air amount, fuel injection control, and ignition of the engine 22 so that the engine 22 is operated by the target rotational speed Ne * and the target torque Te *. The motor ECU 40 that performs control or the like and receives the torque commands Tm1 * and Tm2 * 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 *. By such control, it is possible to travel while outputting the required torque Tr * to the drive shaft 36 within the range of the input / output limits Win and Wout of the battery 50 while operating the engine 22 efficiently. In this engine operation mode, the stop condition of the engine 22 such as when the required power Pe * of the engine 22 falls below the stop threshold Pstop defined as the upper limit of the range of the required power Pe * that should be stopped. When is established, the operation of the engine 22 is stopped and the operation mode is shifted to the motor operation mode.

  In the motor operation mode, the HVECU 70 sets the required torque Tr * based on the accelerator opening Acc and the vehicle speed V, sets a value 0 to the torque command Tm1 * of the motor MG1, and also sets the input / output limits Win and Wout of the battery 50. The torque command Tm2 * of the motor MG2 is set and transmitted to the motor ECU 40 so that the required torque Tr * is output to the drive shaft 36 within the range of. Then, the motor ECU 40 that receives the torque commands Tm1 * and Tm2 * 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 *. With such control, the engine 22 can travel by outputting the required torque Tr * to the drive shaft 36 within the range of the input / output limits Win and Wout of the battery 50 with the engine 22 stopped. In this motor operation mode, when the required power Pe * calculated in the same manner as in the engine operation mode reaches a starting threshold value Pstart determined as the lower limit of the range of the required power Pe * that is better to start the engine 22, the engine When the start condition 22 is satisfied, the engine 22 is started and the engine operation mode is entered.

  Next, the operation of the hybrid vehicle 20 of the embodiment configured in this way, particularly the operation when determining whether or not the fuel property of the engine 22 is relatively difficult to volatilize after the engine 22 is started will be described. To do. FIG. 2 is a flowchart illustrating an example of a heavy fuel determination routine executed by the HVECU 70 of the embodiment. This routine is executed at predetermined time intervals (until the precondition is no longer satisfied) when a precondition for determining whether the fuel of the engine 22 is heavy after the engine 22 is started is satisfied (until the precondition is no longer satisfied). For example, it is repeatedly executed for several msec to 10 msec. Here, the precondition is, for example, that the cooling water temperature Tw of the engine 22 is equal to or lower than a predetermined temperature Twref (for example, 40 ° C., 50 ° C., 60 ° C., etc.) and a predetermined time (for example, 1 second or 2 For example, a condition that is within seconds, 3 seconds, etc.) can be used.

  When the fuel heavy determination routine is executed, the HVECU 70 first inputs data such as the target torque Te * and the output torque Te of the engine 22 (step S100). Here, the target torque Te * of the engine 22 is input as set by the drive control when traveling in the engine operation mode. Further, the output torque Te of the engine 22 is the torque command Tm1 * of the motor MG1 set by the drive control when traveling in the engine operation mode, 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). And the one calculated by the following equation (1) is input. FIG. 3 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 in the engine operation mode. Equation (1) can be easily derived using FIG.

  Te = -Tm1 * ・ (1 + ρ) / ρ (1)

  When data is input in this way, the difference between the input target torque Te * and the target torque (previous Te *) input when this routine was executed last time (the previous value was subtracted from the current value of the target torque Te *). (Absolute value) is calculated as a target torque change amount Ate that is a change amount of the target torque Te * at the effective interval of this routine (step S110), and the calculated target torque change amount Ate is compared with a threshold value Ateref ( Step S120). Here, the threshold value Artef is used to determine whether or not the target torque Te * of the engine 22 is substantially stable. For example, when the effective interval of this routine is about several milliseconds to 10 milliseconds, 5 Nm 6Nm, 7Nm, etc. can be used.

  When the target torque change amount Ate is less than or equal to the threshold value Ateref, it is determined that the target torque Te * of the engine 22 is substantially stable, and the counter Ca, which is set to the initial value 0 when the engine 22 is started, is set to the value 1 only. When the target torque change amount Ate is larger than the threshold value Ateref, it is determined that the target torque Te * of the engine 22 is not stable (changed), and the counter Ca is reset to the value 0 (step S140). Step S150).

  Then, the counter Ca is compared with the threshold value Caref (step S160). Here, the threshold value Carref is used to determine whether or not the torque stable continuation condition in which the target torque Te * of the engine 22 continues for a certain period of time is satisfied, and is, for example, 700 msec. Or a value corresponding to 800 msec, 900 msec, or the like can be used.

  When the counter Ca is less than the threshold value Caref, it is determined that the torque stabilization continuation condition is not satisfied, and processing in steps S150 to S220 (processing for determining whether or not the fuel of the engine 22 is heavy) is executed. Without stopping, this routine is finished as it is.

  When the counter Ca is equal to or greater than the threshold value Caref, it is determined that the torque stabilization continuation condition is satisfied, the output torque Te is subtracted from the target torque Te * of the engine 22, and the torque difference ΔTe between the target torque Te * and the output torque Te. (Step S160), a torque difference threshold ΔTeref is set based on the target torque Te * of the engine 22 (step S170), and the torque difference ΔTe is compared with the torque difference threshold ΔTeref (step S180). Here, the torque difference threshold ΔTeref is used to determine whether or not the fuel of the engine 22 may be heavy. In the embodiment, the torque difference threshold ΔTeref is different from the target torque Te * of the engine 22 and the torque difference. A relationship with the threshold ΔTeref is determined in advance and stored in a ROM (not shown) as a threshold setting map, and when a target torque Te * of the engine 22 is given, a corresponding torque difference threshold ΔTeref is derived and set from the stored map. It was supposed to be. An example of the torque difference threshold setting map is shown in FIG. As shown in the figure, the torque difference threshold ΔTeref is set so as to increase as the target torque Te * of the engine 22 increases. This is because when the fuel of the engine 22 is heavy, the output torque Te tends to be smaller than the target torque Te * as the target torque Te * of the engine 22 increases (the torque difference ΔTe tends to increase). Based.

  When the torque difference ΔTe is less than the threshold value ΔTeref, it is determined that the fuel of the engine 22 is unlikely to be heavy, and the counter Cb, which is set to the initial value 0 when the engine 22 is started, has the value 0 as the lower limit. The value is decremented by 1 (step S190), and when the torque difference ΔTe is greater than or equal to the threshold value ΔTeref, it is determined that the fuel of the engine 22 may be heavy, and the counter Cb is incremented by 1 (step S200). The counter Cb is compared with the threshold value Cbref (step S210). Here, the threshold value Cbref is used to determine whether or not the fuel of the engine 22 may be determined to be heavy (e.g., a value corresponding to 800 msec, 1000 msec, 1200 msec, etc.). Can be used.

  When the counter Cb is less than the threshold value Cbref, the routine is terminated without determining that the fuel of the engine 22 is heavy. On the other hand, when the counter Cb is equal to or greater than the threshold value Cbref, it is determined (determined) that the fuel of the engine 22 is heavy (step S220), and this routine is terminated. When it is determined that the fuel of the engine 22 is heavy in this way, the fuel injection amount is increased and corrected when the engine 22 is subsequently loaded.

  In the embodiment, when the torque stability continuation condition is satisfied, the torque difference ΔTe is compared with a threshold value ΔTeref that tends to increase as the target torque Te * increases, and it is determined whether or not the fuel is the fuel of the engine 22. Thus, it is possible to determine with higher accuracy whether or not the fuel of the engine 22 is heavy as compared with a case where a predetermined value (a uniform value) is used as the threshold value ΔTref. In this determination, when the counter Cb that is incremented by the value 1 when the torque difference ΔTe is equal to or greater than the threshold ΔTeref is equal to or greater than the threshold Cbref, it is determined (determined) that the fuel of the engine 22 is heavy. When the torque difference ΔTe is equal to or greater than the torque difference threshold value ΔTeref, the engine 22 fuel is heavy compared to the engine 22 that immediately determines that the fuel of the engine 22 is heavy (that is, the threshold Tref is a value of 1). It is possible to suppress erroneous determination of whether or not.

  Further, in the embodiment, when the target torque change amount Ate is larger than the threshold value Ateref, the response delay of the engine 22 affects the torque difference ΔTef, so the torque difference ΔTe is not compared with the threshold value ΔTeref (the fuel of the engine 22 is heavy). Therefore, it is possible to suppress erroneous determination of whether or not the fuel of the engine 22 is heavy. Then, as a condition for determining whether or not the torque difference ΔTe is compared with the threshold value ΔTeref, by using the condition that the counter Ca incremented by a value 1 when the target change amount Ate is equal to or smaller than the threshold value Ateref is equal to or larger than the threshold value Caref. It is possible to more appropriately determine whether or not the target torque Te * of the engine 22 is substantially stable. As a cause of the response delay of the engine 22, the change in the output torque Te caused by the delay in the change in the intake air amount Qa when the throttle opening TH is changed in accordance with the change in the target torque Te * of the engine 22. Possible delays.

  According to the hybrid vehicle 20 of the embodiment described above, the torque difference threshold value ΔTeref in which the torque difference ΔTe obtained by subtracting the output torque Te from the target torque Te * of the engine 22 tends to increase as the target torque Te * increases. Since it is determined whether the fuel of the engine 22 is heavy or not, whether the fuel of the engine 22 is heavy compared to the case where a predetermined value (a uniform value) is used as the torque difference threshold value ΔTeref. Whether or not can be determined more accurately.

  Further, according to the hybrid vehicle 20 of the embodiment, when the target torque change amount Ate as the difference between the current value and the previous value of the target torque Te * of the engine 22 is larger than the threshold value Ateref, the torque difference ΔTef is set to the torque difference threshold value ΔTeref. Since it is not compared with (it is not determined whether the fuel of the engine 22 is heavy), it can suppress misjudging whether the fuel of the engine 22 is heavy.

  In the hybrid vehicle 20 of the embodiment, the torque difference ΔTe is compared with the torque difference threshold ΔTeref when the counter Ca that is incremented by a value 1 when the target torque change amount Ate is less than or equal to the threshold Ateref is greater than or equal to the threshold Caref. However, when the target torque change amount Ate is equal to or smaller than the threshold value Ateref, the torque difference ΔTe may be compared with the torque difference threshold value ΔTeref regardless of the value of the counter Ca. That is, the threshold value Carref may be set to the value 1.

  In the hybrid vehicle 20 of the embodiment, when the target torque change amount Ate is larger than the threshold value Ateref, the torque difference ΔTe is not compared with the torque difference threshold value ΔTeref. However, regardless of the magnitude relationship between the target torque change amount Ate and the threshold value Ateref. Instead, the torque difference ΔTe may be compared with the torque difference threshold value ΔTeref.

  In the hybrid vehicle 20 of the embodiment, the counter Cb that is incremented by 1 when the torque difference ΔTe is equal to or greater than the torque difference threshold ΔTeref and decremented by the value 1 when the torque difference ΔTe is less than the torque difference threshold ΔTeref is the threshold Cbref. At this time, it is determined (determined) that the fuel of the engine 22 is heavy. However, when the state where the torque difference ΔTe is equal to or greater than the torque difference threshold ΔTeref continues for a predetermined time, the engine 22 It may be determined (determined) that the fuel is heavy.

  In the hybrid vehicle 20 of the embodiment, the counter Cb that is incremented by 1 when the torque difference ΔTe is equal to or greater than the torque difference threshold ΔTeref and decremented by the value 1 when the torque difference ΔTe is less than the torque difference threshold ΔTeref is the threshold Cbref. At this time, it is determined (determined) that the fuel of the engine 22 is heavy. However, when the torque difference ΔTe is equal to or greater than the torque difference threshold ΔTeref, the fuel of the engine 22 is not related to the value of the counter Cb. It may be determined (determined) as heavy. That is, the threshold value Cbref may be set to a value 1.

  Although not specifically described in the hybrid vehicle 20 of the embodiment, when the engine 22 is autonomously operated (idle operation) after the engine 22 is started, for example, the target rotational speed Ne * (for example, 1100 rpm, 1200 rpm, 1300 rpm) is used. Etc.) is determined based on the magnitude relationship between the rotational speed difference ΔNe obtained by subtracting the rotational speed Ne from a threshold ΔNeref (for example, 250 rpm, 300 rpm, 350 rpm, etc.). And so on.

  In the hybrid vehicle 20 of the embodiment, the power from the motor MG2 is output to the drive shaft 36 connected to the drive wheels 38a and 38b. However, as illustrated in the hybrid vehicle 120 of the modified example of FIG. The power from MG2 may be output to an axle (an axle connected to wheels 39a and 39b in FIG. 5) different from an axle (an axle connected to drive wheels 38a and 38b) to which drive shaft 36 is connected. .

  In the hybrid vehicle 20 of the embodiment, the power from the engine 22 is output to the drive shaft 36 connected to the drive wheels 38a and 38b via the planetary gear 30, but is exemplified in the hybrid vehicle 220 of the modification of FIG. As shown, the inner rotor 232 connected to the crankshaft of the engine 22 and the outer rotor 234 connected to the drive shaft 36 connected to the drive wheels 38a and 38b are used to drive part of the power from the engine 22. A counter-rotor motor 230 that transmits power to the shaft 36 and converts remaining power into electric power may be provided.

  In the hybrid vehicle 20 of the embodiment, the power from the engine 22 is output to the drive shaft 36 connected to the drive wheels 38a and 38b via the planetary gear 30, and the power from the motor MG2 is output to the drive shaft 36. However, as illustrated in the hybrid vehicle 320 of the modified example of FIG. 7, the motor MG is attached to the drive shaft 36 connected to the drive wheels 38a and 38b via the transmission 330, and the clutch 329 is attached to the rotation shaft of the motor MG. The power from the engine 22 is output to the drive shaft 36 via the rotation shaft of the motor MG and the transmission 330, and the power from the motor MG is output to the drive shaft via the transmission 330. It is good also as what outputs 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 problems will be described. In the embodiment, the engine 22 corresponds to the “engine”, the motor MG1 corresponds to the “motor”, and the engine 22 is operated at an operation point including the target rotational speed Ne * and the target torque Te *, and the required torque Tr *. The target rotational speed Ne * and target torque Te * of the engine 22 and torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are set and transmitted to the engine ECU 24 and the motor ECU 40 so as to travel according to HVECU 70 that executes a determination routine, engine ECU 24 that controls engine 22 based on target rotational speed Ne * and target torque Te * of engine 22 from HVECU 70, and torque command Tm1 of motors MG1 and MG2 from HVECU 70 Motor E that controls motors MG1, MG2 based on *, Tm2 * And U40, but it corresponds to the "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 “motor” is not limited to the motor MG1 configured as a synchronous generator motor, and may be any type of motor such as an induction motor. 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. The “control means” controls the engine 22 and the motors MG1, MG2 by setting the target rotational speed Ne * of the engine 22, the target torque Te *, and the torque commands Tm1 *, Tm2 * of the motors MG1, MG2. The engine 22 has a heavier fuel than the torque difference threshold ΔTeref, which is set so that the torque difference ΔTe obtained by subtracting the output torque Te from the target torque Te * of the engine 22 tends to increase as the target torque Te * increases. The engine and the motor are controlled so that the engine travels with the driving torque while being operated at the operation point composed of the target rotational speed and the target torque. The torque difference that is the difference between the output torque and the output torque Anything can be used as long as it can determine whether the fuel is heavy.

  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. In other words, the interpretation of the invention described in the column of means for solving the problem 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 problem. 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, 220, 320 Hybrid vehicle, 21 Fuel tank, 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 electronic control unit (motor ECU), 41, 42 Inverter, 43, 44 Rotation position detection sensor, 50 Battery, 51a Voltage sensor, 51b Current sensor, 51c Temperature sensor, 52 Battery electronic control unit ( Battery ECU), 70 electronic control unit for hybrid vehicle (HVECU), 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position Nsensa, 85 brake pedal, 86 a brake pedal position sensor, 88 vehicle speed sensor, MG1, MG2 motor, 230 pair-rotor motor, 232 an inner rotor, 234 outer rotor, 329 clutch, 330 transmission.

Claims (3)

An engine capable of outputting power for traveling, a motor capable of inputting / outputting power to / from the output shaft of the engine, and the engine travels with traveling torque while being operated at an operating point including a target rotational speed and a target torque. A hybrid vehicle comprising control means for controlling the engine and the motor,
The control means compares the torque difference, which is the difference between the target torque and the output torque, with a torque difference threshold that tends to increase as the target torque increases, and determines whether the fuel of the engine is heavy. It means for determining der is,
The control means is means for not determining whether or not the engine fuel is heavy when a change amount per unit time of the target torque is larger than a change amount threshold value;
The control means compares the torque difference with the torque difference threshold when a second counter that is incremented when a change amount per unit time of the target torque is less than or equal to the change amount threshold is greater than or equal to a second predetermined value. Is a means to
A hybrid vehicle characterized by that. The hybrid vehicle according to claim 1,
The control means is means for determining that the engine fuel is heavy when a counter that is incremented when the torque difference is equal to or greater than the torque difference threshold is equal to or greater than a predetermined value.
Hybrid car. A hybrid vehicle according to claim 1 or 2 ,
A planetary gear in which three rotating elements are connected to a driving shaft connected to an axle, an output shaft of the engine, and a rotating shaft of a generator;
A second motor having a rotor connected to the drive shaft;
A hybrid car with

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