JP2008201351A - Vehicle and control method thereof - Google Patents

Abstract

An object of the present invention is to prevent a driver from feeling uncomfortable due to gearing of a reduction gear connected to a motor and to improve fuel consumption.
When a high vehicle speed determination flag F is a value 0 (low vehicle speed), an engine that is set by a required power Pe * and an optimum fuel consumption operation line when an absolute value of a motor torque (previous Tm2 *) is less than a threshold value T1. The target rotational speed Ne * is increased by a predetermined rotational speed Nset from the operating point (target rotational speed Ne * and target torque Te *) to change the operating point (S140, S150), and the high vehicle speed determination flag F is 1 ( When the vehicle speed is high), the driving point is changed when the absolute value of the motor torque is less than the threshold value T2 smaller than the threshold value T1 (S150, S160). This prevents the driver from feeling uncomfortable due to the gear rattling noise that can occur when the motor is driven with a torque near zero, and the engine is operated at the most efficient operating point possible. Can do.
[Selection] Figure 4

Description

  The present invention relates to an internal combustion engine, a first electric motor for inputting / outputting power, a second electric motor for inputting / outputting power, an output shaft of the internal combustion engine, a rotating shaft of the first electric motor, and a drive shaft connected to an axle. A three-axis power input / output means connected to the three axes of the three axes for inputting / outputting power to the remaining one axis based on the power input / output to / from any two of the three axes, and the second motor by a gear mechanism. A vehicle comprising: a gear-type power transmission means for transmitting power between both shafts by connecting the rotating shaft and the drive shaft; and a power storage means for exchanging power with the first motor and the second motor, and It relates to a control method.

Conventionally, this type of vehicle includes an engine, a planetary gear mechanism having a carrier connected to the output shaft of the engine and a ring gear connected to the drive shaft, and a first motor connected to the sun gear of the planetary gear mechanism. In a hybrid vehicle comprising a second motor connected to the drive shaft via a reduction gear, an engine operating line for avoiding the generation of a booming noise is set, and the engine and the two motors are set based on the set operating line Have been proposed (see, for example, Patent Document 1). In this vehicle, by setting an engine operation line that avoids the generation of a booming noise, the generation of the booming noise can be suppressed and the engine can be operated as efficiently as possible.
JP 2006-2740 A

  As described above, it can be considered as one of the important issues to improve the energy efficiency of the vehicle while preventing the driver from feeling uncomfortable by suppressing the generation of abnormal noise such as a booming noise. In the hybrid vehicle of the type described above, since the second motor is connected to the drive shaft via the reduction gear, rattling noise may be generated in the reduction gear depending on the torque output from the second motor. Therefore, it is desirable to suppress the occurrence of such abnormal noise while improving the energy efficiency of the vehicle.

  One object of the vehicle and the control method thereof according to the present invention is to suppress the generation of abnormal noise that gives the driver a sense of discomfort. Another object of the vehicle and the control method thereof according to the present invention is to further improve energy efficiency.

  The vehicle and the control method thereof according to the present invention employ the following means in order to achieve at least a part of the above-described object.

The vehicle of the present invention
An internal combustion engine;
A first electric motor that inputs and outputs power;
A second electric motor for inputting and outputting power;
It is connected to three shafts of an output shaft of the internal combustion engine, a rotating shaft of the first electric motor, and a drive shaft connected to an axle, and the remaining one is based on power input / output to any two of the three shafts. 3-axis power input / output means for inputting / outputting power to the shaft;
Gear-type power transmission means for transmitting power between the two shafts by connecting the rotating shaft of the second motor and the drive shaft by a gear mechanism;
Power storage means for exchanging power with the first motor and the second motor;
Vehicle speed detection means for detecting the vehicle speed;
It is determined by changing the predetermined driving force range based on the vehicle speed detected by the vehicle speed detecting means whether or not the driving force input / output from the second electric motor is within a predetermined driving force range including a value of zero. Driving force range determination means;
Required driving force setting means for setting required driving force required for the drive shaft;
Required power setting means for setting required power to be output from the internal combustion engine based on the set required driving force;
When the driving force input / output from the second electric motor is determined not to be within the predetermined driving force range by the driving force range determining means, the set required power and predetermined constraints imposed on the internal combustion engine Based on the above, a target operating point consisting of the torque and rotation speed to be output from the internal combustion engine is set, the internal combustion engine is operated at the set target operating point, and the driving force based on the set required driving force is The internal combustion engine, the first electric motor, and the second electric motor are controlled so as to be output to the driving shaft, and the driving force input / output from the second electric motor by the driving force range determining means is the predetermined driving force range. When it is determined that the power is within the range, the gear-type power transmission is performed from an operating point that is set based on the set required power and a predetermined restriction imposed on the internal combustion engine. A target operating point moved in a direction in which abnormal noise of the means is suppressed is set, the internal combustion engine is operated at the set target operating point, and a driving force based on the set required driving force is applied to the driving shaft. The gist of the present invention is to include control means for controlling the internal combustion engine, the first electric motor, and the second electric motor so as to be output.

  In the vehicle of the present invention, it is determined by changing the predetermined driving force range based on the vehicle speed whether or not the driving force input / output from the second electric motor is within the predetermined driving force range including the value 0, and driving The required power to be output from the internal combustion engine is set based on the required driving force required for the shaft, and the determined request is set when it is determined that the driving force input / output from the second electric motor is not within the predetermined driving force range. Based on the power and predetermined constraints imposed on the internal combustion engine, a target operation point consisting of the torque and rotation speed to be output from the internal combustion engine is set, and the internal combustion engine is operated at the set target operation point and requested drive The internal combustion engine, the first electric motor, and the second electric motor are controlled so that the driving force based on the force is output to the driving shaft, and it is determined that the driving force input / output from the second motor is within a predetermined driving force range. Sometimes set The target operating point moved from the operating point set based on the requested power and the predetermined constraint imposed on the internal combustion engine in a direction in which abnormal noise of the gear type power transmission means is suppressed is set and set. The internal combustion engine, the first electric motor, and the second electric motor are controlled so that the internal combustion engine is operated at the target operation point and the driving force based on the required driving force is output to the drive shaft. As a result, it is possible to suppress the driver from feeling uncomfortable due to abnormal noise of the gear type power transmission means. The change of the predetermined driving force range based on the vehicle speed is based on the fact that the noise of the gear type power transmission means can be masked by the noise accompanying the traveling. Therefore, the internal combustion engine can be operated at an operating point set using predetermined restrictions as much as possible. If the restriction that increases the efficiency of the internal combustion engine is used as the predetermined restriction, the energy efficiency of the vehicle can be improved.

  In such a vehicle of the present invention, the driving force range setting means may be means for determining by changing the predetermined driving force range such that the driving speed range setting means tends to become narrower as the vehicle speed detected by the vehicle speed detecting means increases. it can.

  Further, in the vehicle of the present invention, when it is determined that the driving force input / output from the second electric motor is within the predetermined driving force range, the control means applies the set required power and the internal combustion engine. Control is performed by setting a target operation point that is moved in a direction in which abnormal noise of the gear type power transmission means is suppressed while maintaining the required power from the operation point that is set based on a predetermined restriction imposed on the gear. It can also be a means to do. In this way, the required power can be output from the internal combustion engine.

  Furthermore, in the vehicle according to the present invention, when it is determined that the driving force inputted / outputted from the second electric motor is within the predetermined driving force range, the control means applies the set required power and the internal combustion engine. It may be a means for setting and controlling a target operation point in which the rotation speed is moved to the high rotation side from the operation point set based on a predetermined constraint imposed on the vehicle. In this way, torque pulsation from the internal combustion engine can be suppressed, so that generation of noise in the gear type power transmission means due to torque pulsation from the internal combustion engine can be suppressed.

The vehicle control method of the present invention includes:
An internal combustion engine, a first electric motor for inputting / outputting power, a second electric motor for inputting / outputting power, an output shaft of the internal combustion engine, a rotating shaft of the first electric motor, and a drive shaft connected to an axle. Three-axis power input / output means for inputting / outputting power to the remaining one axis based on power input / output to / from any two of the three axes, and a rotating shaft of the second motor by a gear mechanism A vehicle control method comprising gear-type power transmission means for connecting the drive shaft to transmit power between both shafts, and power storage means for exchanging power with the first motor and the second motor. ,
(A) It is determined by changing the predetermined driving force range based on the vehicle speed whether or not the driving force input / output from the second electric motor is within a predetermined driving force range including a value of 0,
(B) setting a required power to be output from the internal combustion engine based on a required driving force required for the drive shaft;
(C) When it is determined that the driving force inputted / outputted from the second electric motor is not within the predetermined driving force range, based on the set required power and the predetermined restriction imposed on the internal combustion engine. A target operating point consisting of torque and rotation speed to be output from the internal combustion engine is set, the internal combustion engine is operated at the set target operating point, and a driving force based on the required driving force is output to the driving shaft. The internal combustion engine, the first electric motor, and the second electric motor are controlled, and when it is determined that the driving force input / output from the second electric motor is within the predetermined driving force range, the set required power And a target operating point that is moved in a direction in which abnormal noise of the gear-type power transmission means is suppressed from an operating point that is set based on a predetermined constraint imposed on the internal combustion engine. The internal combustion engine, the first electric motor, and the second electric motor are controlled so that the internal combustion engine is operated at the set target operation point and a driving force based on the required driving force is output to the driving shaft. This is the gist.

  According to the vehicle control method of the present invention, the predetermined driving force range is changed based on the vehicle speed to determine whether or not the driving force input / output from the second electric motor is within the predetermined driving force range including the value 0. The required power to be output from the internal combustion engine is set based on the required driving force required for the drive shaft, and it is determined that the driving force input / output from the second electric motor is not within the predetermined driving force range. Sometimes, based on the set required power and predetermined constraints imposed on the internal combustion engine, a target operating point consisting of the torque and the number of rotations to be output from the internal combustion engine is set, and the internal combustion engine operates at the set target operating point. In addition, the internal combustion engine, the first electric motor, and the second electric motor are controlled so that the driving force based on the required driving force is output to the driving shaft, and the driving force input / output from the second electric motor is within a predetermined driving force range. Determined to be The target operating point is moved from the operating point set based on the set required power and the predetermined constraints imposed on the internal combustion engine in a direction in which abnormal noise of the gear type power transmission means is suppressed. The internal combustion engine, the first electric motor, and the second electric motor are controlled so that the internal combustion engine is operated at the set target operation point and the driving force based on the required driving force is output to the drive shaft. As a result, it is possible to suppress the driver from feeling uncomfortable due to abnormal noise of the gear type power transmission means. The change of the predetermined driving force range based on the vehicle speed is based on the fact that the noise of the gear type power transmission means can be masked by the noise accompanying the traveling. Therefore, the internal combustion engine can be operated at an operating point set using predetermined restrictions as much as possible. If the restriction that increases the efficiency of the internal combustion engine is used as the predetermined restriction, the energy efficiency of the vehicle can be improved.

  Next, the best mode for carrying out the present invention will be described using examples.

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

  The engine 22 is an internal combustion engine that outputs power using a hydrocarbon-based fuel such as gasoline or light oil, and an engine electronic control unit (hereinafter referred to as an engine ECU) that receives signals from various sensors that detect the operating state of the engine 22. ) 24 is subjected to operation control such as fuel injection control, ignition control, intake air amount adjustment control and the like. The engine ECU 24 is in communication with the hybrid electronic control unit 70, controls the operation of the engine 22 by a control signal from the hybrid electronic control unit 70, and, if necessary, transmits data related to the operating state of the engine 22 to the hybrid electronic control. Output to unit 70.

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

  The reduction gear 35 is configured to reduce the number of rotations of the motor MG2 and transmit it to the ring gear shaft 32a. The reduction gear 35 includes an external gear sun gear 36, an internal gear ring gear 37 disposed concentrically with the sun gear 36, a plurality of pinion gears 38 that mesh with the sun gear 36 and mesh with the ring gear 37, and a plurality of gears It is configured as a planetary gear mechanism including a carrier 39 that holds the pinion gear 38 so as to rotate and revolve. A motor MG2 is connected to the sun gear 36 of the reduction gear 35, and a ring gear shaft 32a is connected to the ring gear 37. The carrier 39 is fixed to the case and its rotation is prohibited.

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

  The battery 50 is managed by a battery electronic control unit (hereinafter referred to as a battery ECU) 52. The battery ECU 52 receives signals necessary for managing the battery 50, for example, a voltage between terminals from a voltage sensor (not shown) installed between terminals of the battery 50, and a power line 54 connected to the output terminal of the battery 50. The charging / discharging current from the attached current sensor (not shown), the battery temperature Tb from the temperature sensor 51 attached to the battery 50, and the like are input. Output to the control unit 70. Further, the battery ECU 52 calculates the remaining capacity (SOC) based on the integrated value of the charging / discharging current detected by the current sensor in order to manage the battery 50, and calculates the remaining capacity (SOC) and the battery temperature Tb. The input / output limits Win and Wout, which are the maximum allowable power that may charge / discharge the battery 50, are calculated based on the above. The input / output limits Win and Wout of the battery 50 are set to basic values of the input / output limits Win and Wout based on the battery temperature Tb, and are input to the output limiting correction coefficient based on the remaining capacity (SOC) of the battery 50. It can be set by setting a correction coefficient for restriction and multiplying the basic value of the set input / output restrictions Win and Wout by the correction coefficient. FIG. 2 shows an example of the relationship between the battery temperature Tb and the input / output limits Win, Wout, and FIG. 3 shows an example of the relationship between the remaining capacity (SOC) of the battery 50 and the correction coefficients of the input / output limits Win, Wout.

  The hybrid electronic control unit 70 is configured as a microprocessor centered on the CPU 72, and in addition to the CPU 72, a ROM 74 for storing processing programs, a RAM 76 for temporarily storing data, an input / output port and communication not shown. And a port. The hybrid electronic control unit 70 includes an ignition signal from an ignition switch 80, a shift position SP from a shift position sensor 82 that detects the operation position of the shift lever 81, and an accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. The accelerator pedal opening Acc from the vehicle, the brake pedal position BP from the brake pedal position sensor 86 for detecting 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 hybrid electronic control unit 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52. ing.

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

  Next, the operation of the thus configured hybrid vehicle 20 of the embodiment will be described. FIG. 4 is a flowchart showing an example of a drive control routine executed by the hybrid electronic control unit 70. This routine is repeatedly executed every predetermined time (for example, every several msec).

  When the drive control routine is executed, first, the CPU 72 of the hybrid electronic control unit 70 first determines the accelerator opening Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 88, the rotational speed Nm1, of the motors MG1, MG2. A process of inputting data necessary for control such as Nm2, input / output limits Win and Wout of the battery 50, and a high vehicle speed determination flag F is executed (step S100). Here, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 are input from the motor ECU 40 by communication from those calculated based on the rotational positions of the rotors of the motors MG1 and MG2 detected by the rotational position detection sensors 43 and 44. To do. Further, the input / output limits Win and Wout of the battery 50 are set based on the battery temperature Tb of the battery 50 and the remaining capacity (SOC) of the battery 50 and are input from the battery ECU 52 by communication. As the high vehicle speed determination flag F, the high vehicle speed determination flag F set by the high vehicle speed determination routine illustrated in FIG. 5 executed by the hybrid electronic control unit 70 is input. In the high vehicle speed determination routine, as shown in the figure, the vehicle speed V is input from the vehicle speed sensor 88 (step S300), the current high vehicle speed determination flag F is checked (step S310), and the current high vehicle speed determination flag F is determined. When the value is 0, when the input vehicle speed V is equal to or higher than the threshold value V1 (for example, 10 km / h or 12 km / h) (step S320), the high vehicle speed determination flag F is set to 1 (step S330), and the current high vehicle speed determination is performed. When the flag F is a value 1, when the input vehicle speed is less than a threshold value V2 (for example, 7 km / h, 9 km / h, etc.) (step S340), the high vehicle speed determination flag F is set to a value 0 (step S350). When the current high vehicle speed determination flag F is 0 and the vehicle speed V is less than the threshold V1, or when the current high vehicle speed determination flag F is 1 and the vehicle speed V is equal to or greater than the threshold V2, the high vehicle speed determination flag F No changes are made. The threshold values V1 and V2 are provided with hysteresis so that the value of the high vehicle speed determination flag F is not changed frequently.

  When the data is thus input, the required torque Tr * to be output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 63a and 63b as the torque required for the vehicle based on the input accelerator opening Acc and the vehicle speed V. And the required power Pe * required for the engine 22 is set (step S110). In the embodiment, the required torque Tr * is determined in advance by storing the relationship between the accelerator opening Acc, the vehicle speed V, and the required torque Tr * in the ROM 74 as a required torque setting map, and the accelerator opening Acc, the vehicle speed V, , The corresponding required torque Tr * is derived and set from the stored map. FIG. 6 shows an example of the required torque setting map. The required power Pe * can be calculated as the sum of the set required torque Tr * multiplied by the rotational speed Nr of the ring gear shaft 32a and the charge / discharge required power Pb * required by the battery 50 and the loss Loss. The rotational speed Nr of the ring gear shaft 32a is obtained by multiplying the vehicle speed V by a conversion factor k (Nr = k · V), or the rotational speed Nm2 of the motor MG2 is divided by the gear ratio Gr of the reduction gear 35 (Nr = Nm2 / Gr).

  Subsequently, a target rotational speed Ne * and a target torque Te * are set as operating points at which the engine 22 should be operated based on the set required power Pe * (step S120). This setting is performed based on the optimum fuel consumption operation line for efficiently operating the engine 22 and the required power Pe *. FIG. 7 shows an example of the operation line of the engine 22 and how the target rotational speed Ne * and the target torque Te * are set. As shown in the figure, the target rotational speed Ne * and the target torque Te * can be obtained from the intersection of the operation line and a curve with a constant required power Pe * (Ne * × Te *).

  Next, the value of the input high vehicle speed determination flag F is checked (step S130). When the high vehicle speed determination flag F is 0, the torque command of the motor MG2 previously set in this routine as the torque output from the motor MG2 ( The absolute value of the previous Tm2 *) is compared with the threshold value T1 (step S140). If the absolute value of the previous Tm2 * is less than the threshold value T1, the predetermined rotational speed Nset is set to the target rotational speed Ne * of the engine 22 set in step S120. To change the target rotational speed Ne * and change the target torque Te * by dividing the required power Pe * of the engine 22 by the changed target rotational speed Ne * (step S150), and the absolute value of the previous Tm2 * Is equal to or greater than the threshold value T1, the target rotational speed Ne * and the target torque Te of the engine 22 set in step S120. It does not change. Here, the threshold value T1 defines a torque range of the motor MG2 in which the operation point (target rotational speed Ne * and target torque Te *) of the engine 22 is to be changed. FIG. 8 shows how the operating point of the engine 22 is changed. As shown in the figure, the operating point of the engine 22 is changed such that the target rotational speed Ne * and the target torque Te * are increased so that the target rotational speed Ne * is increased by a predetermined rotational speed Nset while the required power Pe * of the engine 22 is maintained. This is done by changing

  When the high vehicle speed determination flag F is determined to be 1 in step S130, the absolute value of the torque (previous Tm2 *) output from the motor MG2 is compared with the threshold T2 (step S160), and the absolute value of the previous Tm2 * is determined. Is less than the threshold T2, the operating point of the engine 22 is changed so that the target rotational speed Ne * is increased by the predetermined rotational speed Nset (step S150), and when the absolute value of the previous Tm2 * is equal to or higher than the threshold T2, the operating point of the engine 22 is changed. Does not change. FIG. 9 shows the relationship between the torque of the motor MG2 (previous Tm2 *), the vehicle speed V, and the operating point change region in which the operating point of the engine 22 should be changed. As shown in the figure, the threshold value T2 is set so that the torque range of the motor MG2 whose operating point of the engine 22 should be changed is narrower than the threshold value T1.

  Consider a state in which the motor MG2 is being driven with a torque in the vicinity of a value of zero. The engine 22 generates torque pulsation due to the reciprocating motion of the piston accompanying explosion combustion, and the torque pulsation increases as the rotational speed Ne decreases. Such torque pulsation from the engine 22 does not act on the ring gear shaft 32a unless the inertia due to the mass of the rotor of the motor MG1 is taken into consideration, but actually the mass of the rotor of the motor MG1 causes the ring gear shaft 32a to move from the engine 22 to the ring gear shaft 32a. When the motor MG2 is driven with a torque near 0, the gears of the reduction gear 35 rattle each other and noise is generated, which may give the driver a sense of discomfort. Therefore, if the operating point of the engine 22 is changed so that the target rotational speed Ne * is increased by the predetermined rotational speed Nset, the torque pulsation from the engine 22 is reduced, so that the torque pulsation from the engine 22 acts on the ring gear shaft 32a. It is possible to suppress the rattling noise of the reduction gear 35 that can be generated. On the other hand, such a change in the operating point of the engine 22 causes the operating point to be removed from the optimum fuel efficiency operation line, resulting in a decrease in energy efficiency of the engine 22. In the embodiment, when the vehicle is traveling at a relatively high speed (when the high speed determination flag F is 1), this rattling noise is generated by the traveling noise even if some gearing occurs in the reduction gear 35. By narrowing the operating point change area as it can be masked by (dark noise) (see FIG. 9), the engine 22 is optimized as much as possible without causing the driver to feel uncomfortable due to the rattling sound of the reduction gear 35. The energy efficiency of the engine 22 is improved by operating on the fuel efficiency operation line.

  When the target rotational speed Ne * and the target torque Te * of the engine 22 are set, the following equation is obtained 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 power distribution and integration mechanism 30. The target rotational speed Nm1 * of the motor MG1 is calculated by (1), and the torque command Tm1 to be output from the motor MG1 by Expression (2) based on the calculated target rotational speed Nm1 * and the input rotational speed Nm1 of the motor MG1. * Is calculated (step S170). Here, Expression (1) is a dynamic relational expression for the rotating element of the power distribution and integration mechanism 30. FIG. 10 is a collinear diagram showing a dynamic relationship between the number of rotations and torque in the rotating elements of the power distribution and integration mechanism 30 when traveling with the power output from the engine 22. In the figure, the left S-axis indicates the rotation speed of the sun gear 31 that is the rotation speed Nm1 of the motor MG1, the C-axis indicates the rotation speed of the carrier 34 that is the rotation speed Ne of the engine 22, and the R-axis indicates the rotation speed of the motor MG2. The rotational speed Nr of the ring gear 32 obtained by dividing the number Nm2 by the gear ratio Gr of the reduction gear 35 is shown. Expression (1) can be easily derived by using this alignment chart. The two thick arrows on the R axis indicate that the torque Tm1 output from the motor MG1 acts on the ring gear shaft 32a and the torque Tm2 output from the motor MG2 acts on the ring gear shaft 32a via the reduction gear 35. Torque. Expression (2) is a relational expression in feedback control for rotating the motor MG1 at the target rotational speed Nm1 *. In Expression (2), “k1” in the second term on the right side is a gain of a proportional term. “K2” in the third term on the right side is the gain of the integral term.

Nm1 * = Ne * ・ (1 + ρ) / ρ-Nm2 / ρ (1)
Tm1tmp = ρ ・ Te * / (1 + ρ) + k1 (Nm1 * -Nm1) + k2∫ (Nm1 * -Nm1) dt (2)

  Then, the torque command Tm1 * set as the required torque Tr * is divided by the gear ratio ρ of the power distribution and integration mechanism 30 and further divided by the gear ratio Gr of the reduction gear 35 to obtain the torque to be output from the motor MG2. A temporary torque Tm2tmp, which is a temporary value, is calculated by the following equation (3) (step S180), and the input / output limits Win and Wout of the battery 50 and the set torque command Tm1 * are multiplied by the current rotational speed Nm1 of the motor MG1. The torque limits Tm2min and Tm2max as upper and lower limits of the torque that may be output from the motor MG2 by dividing the deviation from the power consumption (generated power) of the motor MG1 obtained by the number of revolutions Nm2 of the motor MG2 ) And equation (5) (step S190), and the set temporary torque Tm2tmp is calculated according to equation (6). Click restriction Tm2min, to limit to set a torque command Tm2 * of the motor MG2 by Tm2max (step S200). Here, Expression (3) can be easily derived from the alignment chart of FIG.

Tm2tmp = (Tr * + Tm1 * / ρ) / Gr (3)
Tm2min = (Win-Tm1 * ・ Nm1) / Nm2 (4)
Tm2max = (Wout-Tm1 * ・ Nm1) / Nm2 (5)
Tm2 * = max (min (Tm2tmp, Tm2max), Tm2min) (6)

  Thus, when the target engine speed Ne *, the target torque Te *, and the torque commands Tm1 *, Tm2 * of the motors MG1, MG2 are set, the target engine speed Ne * and the target torque Te * of the engine 22 are set in the engine ECU 24. Torque commands Tm1 * and Tm2 * for motors MG1 and MG2 are transmitted to motor ECU 40 (step S210), and the drive control 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 in the engine 22 so that the engine 22 is operated at the operating point indicated by the target rotational speed Ne * and the target torque Te *. Controls such as fuel injection control and ignition control. The motor ECU 40 that has received the torque commands Tm1 * and Tm2 * controls the switching elements of the inverters 41 and 42 so that the motor MG1 is driven by the torque command Tm1 * and the motor MG2 is driven by the torque command Tm2 *. To do. By such control, the engine 22 can be efficiently operated within the range of the input / output limits Win and Wout of the battery 50, and the required torque Tr * can be output to the ring gear shaft 32a as a drive shaft to travel.

  According to the hybrid vehicle 20 of the embodiment described above, the operating point change region in which the torque range of the motor MG2 to change the operating point of the engine 22 is changed based on the vehicle speed V is set, and the ring gear as the drive shaft is set. Based on the required torque Tr * required for the shaft 32a, the required power Pe * to be output from the engine 22 is set. When the torque output from the motor MG2 is not within the operating point change region, the required power Pe * is set. Based on the optimum fuel efficiency operation line, the operating point (target rotational speed Ne * and target torque Te *) of the engine 22 is set, and the engine 22 is operated at this operating point and the required torque Tr * is output to the ring gear shaft 32a. The engine 22, the motor MG1, and the motor MG2 are controlled so that the motor MG2 When the torque to be applied is within the range of the operating point change area, the target rotational speed Ne * is changed from the operating point set based on the required power Pe * and the optimum fuel efficiency operation line so that the target rotational speed Ne * is increased by a predetermined rotational speed Nset. Since the engine 22 is operated at the changed operating point and the engine 22, the motor MG 1, and the motor MG 2 are controlled so that the required torque Tr * is output to the ring gear shaft 32 a, Can suppress a sense of incongruity. This operating point change area is set so that the torque range of the motor MG2 to change the operating point of the engine 22 when the vehicle speed V is relatively large (when the high vehicle speed determination flag F is 1) is narrowed. The engine 22 can be operated at as efficient an operating point as possible. As a result, the energy efficiency of the vehicle can be improved.

  In the hybrid vehicle 20 of the embodiment, as illustrated in FIG. 8, the driving point change region is set based on the torque range of the motor MG2 that is widened or narrowed in two stages depending on the size of the vehicle speed V. The operating point change area may be set with a range of torque of the motor MG2 that is widened or narrowed by three or more stages, or the operating point change area is set with a range of torque of the motor MG2 that gradually decreases as the vehicle speed V increases. Alternatively, the operating point change area may be set so that the operating point of the engine 22 is changed only when the vehicle speed V is less than the predetermined vehicle speed. An example of such an operating point change area is shown in FIGS.

  In the hybrid vehicle 20 of the embodiment, when the torque (previous Tm2 *) output from the motor MG2 is within the range of the operating point change region, the target rotational speed Ne of the engine 22 is maintained while the required power Pe * of the engine 22 is maintained. * Increases the target rotational speed Ne * and the target torque Te * by increasing the predetermined rotational speed Nset, but moves the operating point of the engine 22 in a direction to suppress the rattling noise of the reduction gear 35 If so, for example, power larger than the required power Pe * may be output from the engine 22 so that the target rotational speed Ne * is increased by a predetermined rotational speed Nset, or a lower limit rotational speed of the engine 22 is set. The operating point of the engine 22 may be changed so that the target rotational speed Ne * does not fall below the lower limit rotational speed.When the engine 22 outputs a power larger than the required power Pe *, surplus energy is generated from the engine 22 and this energy is stored in the battery 50.

  In the hybrid vehicle 20 according to the embodiment, the torque output from the motor MG2 is used as the torque command Tm2 * of the motor MG2 set in the previous drive control routine, and it is determined whether or not the torque is within the operating point change region. Although the determination is made, the present invention is not limited to this, and the torque output from the motor MG2 may be estimated by detecting the phase current applied to the motor MG2.

  In the hybrid vehicle 20 of the embodiment, the motor MG2 is attached to the ring gear shaft 32a as the drive shaft via the reduction gear 35, but is not limited to the reduction gear 35, and the ring gear shaft 32a is not limited to the gear mechanism. If the motor MG2 is attached to the ring gear shaft 32a, for example, the motor MG2 may be attached to the ring gear shaft 32a via a transmission such as a two-speed shift, a three-speed shift, or a four-speed shift instead of the reduction gear 35.

  Here, 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 “internal combustion engine”, the motor MG1 corresponds to the “first electric motor”, the motor MG2 corresponds to the “second electric motor”, and the power distribution and integration mechanism 30 corresponds to the “three-shaft power”. The speed reduction gear 35 corresponds to “gear-type power transmission means”, the battery 50 corresponds to “power storage means”, the vehicle speed sensor 88 corresponds to “vehicle speed detection means”, and the vehicle speed V corresponds to “input / output means”. Based on the operating point change area in which the torque range of the motor MG2 that should change the operating point of the engine 22 is changed, it is determined whether or not the torque output from the motor MG2 is within the operating point change area. The hybrid electronic control unit 70 that executes the processing of steps S130, S140, and S160 of the high vehicle speed determination routine and the drive control routine corresponds to the “driving force range determination means”. The hybrid electronic control unit 70 that executes the process of step S110 of the drive control routine of FIG. 5 that sets the required torque Tr * based on the cell opening degree Acc and the vehicle speed V corresponds to “required drive force setting means”. The hybrid electronic control unit 70 that executes the process of step S120 of the drive control routine for setting the required power Pe * to be output from the engine 22 based on the required torque Tr * required for the ring gear shaft 32a as the drive shaft is " It corresponds to “required power setting means”, and when the torque output from the motor MG2 is not within the range of the operation point change region, the operation point of the engine 22 is set based on the required power Pe * and the optimum fuel consumption operation line. The engine 22 is operated at the operating point and the required torque Tr * is applied to the ring gear shaft 3 When the torque output from the motor MG2 is within the operating point change range, the target rotational speed Ne * is rotated at a predetermined speed from the operating point set based on the required power Pe * and the optimum fuel efficiency operation line. The target rotational speed Ne * and the target torque Te * of the engine 22 are set so that the engine 22 is operated at the changed operating point and the required torque Tr * is output to the ring gear shaft 32a. At the same time, the engine 22 is set on the basis of the hybrid electronic control unit 70 that sets torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 and transmits them to the engine ECU 24 and the motor ECU 40, the target rotational speed Ne *, and the target torque Te *. Based on the engine ECU 24 for controlling the torque and torque commands Tm1 *, Tm2 * The motor ECU 40 that controls the motors MG1 and MG2 corresponds to “control means”. Here, the “internal combustion engine” is not limited to an internal combustion engine that outputs power using a hydrocarbon fuel such as gasoline or light oil, and may be any type of internal combustion engine such as a hydrogen engine. The “first motor” is not limited to the motor MG1 configured as a synchronous generator motor, and may be any type of motor as long as it can input and output power. 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. The “three-axis power input / output means” is not limited to the power distribution / integration mechanism 30 described above, but includes four or more shafts using a double pinion type planetary gear mechanism or a combination of a plurality of planetary gear mechanisms. Or a differential gear such as a differential gear that is different from a planetary gear, such as a drive shaft, an output shaft, and a rotating shaft of a generator. As long as power is input / output to / from the remaining shafts based on the power input / output to / from the shafts, any device may be used. The “gear-type power input / output means” is not limited to the reduction gear 35, and a rotation mechanism and a drive shaft of the second electric motor are connected by a gear mechanism, such as a transmission that transmits power by changing a gear position. As long as it is connected and transmits power between both shafts, it may be anything. The “storage means” is not limited to the battery 50 as a secondary battery, and may be anything as long as it can exchange power with the first motor and the second motor, such as a capacitor. The “vehicle speed detection means” is not limited to the vehicle speed sensor 88, but is used to calculate the vehicle speed V based on the rotation speed of the ring gear shaft 32a as a drive shaft, or to be attached to the drive wheels 63a, 63b and the driven wheels. Any device that detects the vehicle speed, such as a device that calculates the vehicle speed V based on a signal from the wheel speed sensor, may be used. The “required driving force setting means” is not limited to the one that sets the required torque Tr * based on the accelerator opening Acc and the vehicle speed V, but sets the required torque based only on the accelerator opening Acc. If the required driving force required for traveling is set, such as those for which the required torque is set based on the traveling position on the traveling route, such as those for which the driving route is set in advance I do not care. As the “driving force range determination means”, when the high vehicle speed determination flag F has a value of 0, the range of torque of the motor MG2 whose operating point of the engine 22 should be changed is determined by the threshold T1, and the high vehicle speed determination flag F has a value of 1. Whether or not the torque output from the motor MG2 is within the range of the operating point change area using the operating point change area that defines the torque range of the motor MG2 whose operating point of the engine 22 should be changed by the threshold value T2. The predetermined driving force is determined based on the vehicle speed detected by the vehicle speed detecting means whether or not the driving force input / output from the electric motor is within a predetermined driving force range including the value 0. Any method can be used as long as it is determined by changing the range. As the “control means”, when the torque output from the motor MG2 is not within the range of the operating point change region, the operating point of the engine 22 is set based on the required power Pe * and the optimum fuel consumption operation line. The engine 22, the motor MG1, and the motor MG2 are controlled so that the required torque Tr * is output to the ring gear shaft 32a and the torque output from the motor MG2 is within the operating point change region. In some cases, the target rotational speed Ne * is changed from the operating point set based on the required power Pe * and the optimum fuel efficiency operation line so that the target rotational speed Ne * is increased by a predetermined rotational speed Nset, and the engine 22 is operated at the changed operating point. The engine 22 so that the required torque Tr * is output to the ring gear shaft 32a; It is not limited to controlling the motor MG1 and the motor MG2, and when it is determined that the driving force input / output from the second electric motor is not within the predetermined driving force range, the required power and the internal combustion engine are controlled. The target operating point consisting of the torque and the number of revolutions to be output from the internal combustion engine is set on the basis of the predetermined constraints imposed, and the internal combustion engine is operated at the set target operating point and the driving force based on the required driving force is driven to the drive shaft The internal combustion engine, the first electric motor, and the second electric motor are controlled so as to be output to each other, and when it is determined that the driving force input / output from the second electric motor is within a predetermined driving force range, Target operation point set and set from the operation point set based on the predetermined constraints imposed in the direction in which abnormal noise of the gear type power transmission means is suppressed As long as it controls the internal combustion engine and the first electric motor and the second electric motor so that the driving force based on the required driving force with the internal combustion engine is operated is output to the drive shaft in Into may be any ones. Further, the “control unit” is not limited to the combination of the hybrid electronic control unit 70, the engine ECU 24, and the motor ECU 40, and may be configured by a single electronic control unit. 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. It is an example for specifically explaining the best mode for doing so, and does not limit the elements of the invention described in the column of means for solving the problem. 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.

  The best mode for carrying out the present invention has been described with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the gist of the present invention. Of course, it can be implemented in the form.

  The present invention is applicable to the automobile industry.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 according to an embodiment of the present invention. It is explanatory drawing which shows an example of the relationship between the battery temperature Tb in the battery 50, and the input / output restrictions Win and Wout. It is explanatory drawing which shows an example of the relationship between the remaining capacity (SOC) of the battery 50, and the correction coefficient of input / output restrictions Win and Wout. It is a flowchart which shows an example of the drive control routine performed by the electronic control unit for hybrids 70 of an Example. It is a flowchart which shows an example of the high vehicle speed determination routine performed by the electronic control unit for hybrid 70 of an Example. It is explanatory drawing which shows an example of the map for request | requirement torque setting. It is explanatory drawing which shows a mode that an example of the operating line of the engine 22, the target rotational speed Ne *, and the target torque Te * are set. It is explanatory drawing which shows an example of a mode that the driving | running | working point of the engine 22 is changed only by predetermined rotation speed Nset. It is explanatory drawing which shows an example of the relationship between the vehicle speed V, the torque output from motor MG2, and a driving point change area | region. FIG. 3 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 a power distribution and integration mechanism 30 when traveling with power output from an engine 22; It is explanatory drawing which shows an example of the driving | running | working point change area | region of a modification. It is explanatory drawing which shows an example of the driving | running | working point change area | region of a modification. It is explanatory drawing which shows an example of the driving | running | working point change area | region of a modification.

Explanation of symbols

  20 hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 26 crankshaft, 28 damper, 30 power distribution and integration mechanism, 31 sun gear, 32 ring gear, 32a ring gear shaft, 33 pinion gear, 34 carrier, 35 reduction gear , 36 sun gear, 37 ring gear, 38 pinion gear, 39 carrier, 40 electronic control unit for motor (motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 50 battery, 51 temperature sensor, 52 electronic control unit for battery (Battery ECU), 54 power line, 60 gear mechanism, 62 differential gear, 63a, 63b driving wheel, 70 electronic control unit for hybrid, 72 CPU, 74 ROM, 76 RA , 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 an accelerator pedal position sensor, 85 brake pedal, 86 a brake pedal position sensor, 88 vehicle speed sensor, MG1, MG2 motor.

Claims (6)

An internal combustion engine;
A first electric motor that inputs and outputs power;
A second electric motor for inputting and outputting power;
It is connected to three shafts of an output shaft of the internal combustion engine, a rotating shaft of the first electric motor, and a drive shaft connected to an axle, and the remaining one is based on power input / output to any two of the three shafts. 3-axis power input / output means for inputting / outputting power to the shaft;
Gear-type power transmission means for transmitting power between the two shafts by connecting the rotating shaft of the second motor and the drive shaft by a gear mechanism;
Power storage means for exchanging power with the first motor and the second motor;
Vehicle speed detection means for detecting the vehicle speed;
It is determined by changing the predetermined driving force range based on the vehicle speed detected by the vehicle speed detecting means whether or not the driving force input / output from the second electric motor is within a predetermined driving force range including a value of zero. Driving force range determination means;
Required driving force setting means for setting required driving force required for the drive shaft;
Required power setting means for setting required power to be output from the internal combustion engine based on the set required driving force;
When the driving force input / output from the second electric motor is determined not to be within the predetermined driving force range by the driving force range determining means, the set required power and predetermined constraints imposed on the internal combustion engine Based on the above, a target operating point consisting of the torque and rotation speed to be output from the internal combustion engine is set, the internal combustion engine is operated at the set target operating point, and the driving force based on the set required driving force is The internal combustion engine, the first electric motor, and the second electric motor are controlled so as to be output to the driving shaft, and the driving force input / output from the second electric motor by the driving force range determining means is the predetermined driving force range. When it is determined that the power is within the range, the gear-type power transmission is performed from an operating point that is set based on the set required power and a predetermined restriction imposed on the internal combustion engine. A target operating point moved in a direction in which abnormal noise of the means is suppressed is set, the internal combustion engine is operated at the set target operating point, and a driving force based on the set required driving force is applied to the driving shaft. A vehicle comprising: control means for controlling the internal combustion engine, the first electric motor, and the second electric motor so as to be output.   2. The vehicle according to claim 1, wherein the driving force range setting means is a means for determining by changing the predetermined driving force range such that the driving force range setting means tends to become narrower as the vehicle speed detected by the vehicle speed detecting means increases.   When it is determined that the driving force input / output from / to the second electric motor is within the predetermined driving force range, the control means includes the set required power and predetermined constraints imposed on the internal combustion engine. 2. A means for setting and controlling a target operating point that is moved in a direction in which abnormal noise of the gear type power transmission means is suppressed while maintaining the required power from the operating point set based on 2. The vehicle according to 2.   When it is determined that the driving force input / output from / to the second electric motor is within the predetermined driving force range, the control means includes the set required power and predetermined constraints imposed on the internal combustion engine. The vehicle according to any one of claims 1 to 3, wherein the vehicle is a means for setting and controlling a target driving point obtained by moving the rotational speed to the high-rotation side from the driving point set based on.   The vehicle according to any one of claims 1 to 4, wherein the predetermined constraint is a constraint that increases the efficiency of the internal combustion engine. An internal combustion engine, a first electric motor for inputting / outputting power, a second electric motor for inputting / outputting power, an output shaft of the internal combustion engine, a rotating shaft of the first electric motor, and a drive shaft connected to an axle. Three-axis power input / output means for inputting / outputting power to the remaining one axis based on power input / output to / from any two of the three axes, and a rotating shaft of the second motor by a gear mechanism A vehicle control method comprising gear-type power transmission means for connecting the drive shaft to transmit power between both shafts, and power storage means for exchanging power with the first motor and the second motor. ,
(A) It is determined by changing the predetermined driving force range based on the vehicle speed whether or not the driving force input / output from the second electric motor is within a predetermined driving force range including a value of 0,
(B) setting a required power to be output from the internal combustion engine based on a required driving force required for the drive shaft;
(C) When it is determined that the driving force inputted / outputted from the second electric motor is not within the predetermined driving force range, based on the set required power and the predetermined restriction imposed on the internal combustion engine. A target operating point consisting of torque and rotation speed to be output from the internal combustion engine is set, the internal combustion engine is operated at the set target operating point, and a driving force based on the required driving force is output to the driving shaft. The internal combustion engine, the first electric motor, and the second electric motor are controlled, and when it is determined that the driving force input / output from the second electric motor is within the predetermined driving force range, the set required power And a target operating point that is moved in a direction in which abnormal noise of the gear-type power transmission means is suppressed from an operating point that is set based on a predetermined constraint imposed on the internal combustion engine. The internal combustion engine, the first electric motor, and the second electric motor are controlled so that the internal combustion engine is operated at the set target operation point and a driving force based on the required driving force is output to the driving shaft. Vehicle control method.

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