JP3929435B2 - Power output apparatus, automobile equipped with the same, and control method of power output apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To change the gear change ratio of a gear change transmission in which the transmission of the power from the rotary shaft of a motor to a drive shaft is performed at a changeable gear change ratio, more properly, by considering the charging/discharging power of an electric storage unit, such as a secondary battery, etc., or considering the drive state of the motor. <P>SOLUTION: In a power output device, the output shaft of an engine is connected to the drive shaft coupled to an axle through a planetary gear mechanism, a generator is connected to the rotary element of the planetary gear mechanism, and the gear change of the transmission of the power output device in which the motor is connected to the drive shaft through the transmission is switched when a vehicle speed V, the required torque Tr* required to the drive shaft and the torque outputted from the motor to the power which charges and discharges the battery become near a value "0" at a positive side. Thus, the gear change of the transmission can be performed more properly. <P>COPYRIGHT: (C)2005,JPO&amp;NCIPI

Description

  The present invention relates to a power output apparatus, an automobile equipped with the power output apparatus, and a method for controlling the power output apparatus.

Conventionally, as this type of power output device, an engine output shaft is connected to a drive shaft connected to an axle via a planetary gear mechanism, a generator is connected to a rotating element of the planetary gear mechanism, and a speed change is made to the drive shaft. The thing mounted in the motor vehicle which connected the electric motor via the machine is proposed (for example, refer patent document 1). In this apparatus, the power from the electric motor is changed to the power corresponding to the vehicle speed and is output to the drive shaft by changing the gear position of the transmission according to the vehicle speed.
JP 2002-225578 A (FIG. 1)

  However, in the above-described power output apparatus, although it is described that the speed change stage of the transmission is set to the speed change stage according to the vehicle speed, the battery charge / discharge power and the driving state of the electric motor are not sufficiently considered. Assuming that the gear stage of the transmission is changed based only on the vehicle speed, regardless of the charge / discharge power of the battery, the charge / discharge power of the battery is covered by the power from the internal combustion engine. As a result, the drive point of the electric motor is changed, and in some cases, the electric motor is operated at an inefficient operation point. In the case of a stepped transmission, many of them are combined with a planetary gear mechanism and provided with clutches and brakes for the plurality of rotating elements to change the connection relationship of the rotating elements or to restrict the rotation of the rotating elements. Shifts. At this time, in consideration of durability such as wear of the clutch and the brake, there is a driving state suitable for gear shifting, and it is preferable to shift gears in that driving state. Therefore, if the gear stage of the transmission is changed based on only the vehicle speed without considering the driving state of the motor, the gear may shift even when the driving state of the motor is not suitable for gear shifting. Arise.

  The power output device of the present invention, a vehicle equipped with the power output device, and a control method for the power output device include the rotating shaft of the motor by considering the charge / discharge power of a power storage device such as a secondary battery or the driving state of the motor. One of the purposes is to more appropriately change the speed ratio in the speed change transmission device that performs transmission of power to the drive shaft with a changeable speed ratio. It is an object of the power output apparatus, the automobile on which the power output apparatus is mounted, and the control method for the power output apparatus of the present invention to improve the energy efficiency of the apparatus and the automobile.

  In order to achieve at least a part of the above object, the power output apparatus of the present invention, the automobile equipped with the power output apparatus, and the control method of the power output apparatus employ the following means.

The power output apparatus of the present invention is
A power output device that outputs power to a drive shaft,
An internal combustion engine;
An electric power drive input / output means connected to the output shaft of the internal combustion engine and the drive shaft, and outputting at least a part of the power from the internal combustion engine to the drive shaft with input / output of electric power;
An electric motor that can input and output power;
Shift transmission means for performing transmission of power between the rotating shaft of the electric motor and the drive shaft with a changeable gear ratio;
A power storage means capable of exchanging power with the electric power drive input / output means and the electric motor;
Required power setting means for setting required power to charge / discharge the power storage means based on the state of the power storage means;
Requested power setting means for setting required power to be output to the drive shaft based on an operation of an operator;
A transmission ratio setting means for setting a transmission ratio in the transmission transmission means based on the set required power and the set required power;
Power is transmitted between the rotating shaft of the electric motor and the drive shaft with the set speed ratio, and the power storage means is charged / discharged by the electric power based on the set required power, and the set required power is obtained. Control means for controlling the internal combustion engine, the electric power drive input / output means, the electric motor, and the shift transmission means so that power based on the power is output to the drive shaft;
It is a summary to provide.

  In the power output device of the present invention, the required power to be charged / discharged for the power storage means is set based on the state of the power storage means, and the required power to be output to the drive shaft is set based on the operation of the operator, thus Based on the set required power and required power, a transmission gear ratio is set in the transmission transmission means for performing transmission of power between the rotating shaft of the motor and the drive shaft with a changeable gear ratio. Then, power is transmitted between the rotating shaft of the motor and the drive shaft with the set speed ratio, and the power storage means is charged / discharged by the power based on the set required power, and the power based on the set required power is supplied to the drive shaft. The internal combustion engine, the power drive input / output means, the electric motor, and the transmission transmission means are controlled so as to be output. In other words, the power storage means is shifted based on the required power to be charged / discharged, so that the gear can be shifted within a range where the electric motor can be driven efficiently. As a result, the energy efficiency of the apparatus can be improved. Here, the drive shaft may be a single shaft or a plurality of different shafts.

  In such a power output apparatus of the present invention, the speed change transmission means is means for transmitting the power by switching between two speed ratios, and the speed ratio setting means sets a speed ratio switching point in the speed change transmission means. It can also be a means to do. In this case, the gear ratio setting means may be means for setting the gear ratio switching point so that the torque output from the electric motor is close to zero. In this way, the gear ratio can be switched according to the driving state of the electric motor. Further, it is possible to easily perform a shift in the shift transmission means and to suppress a shock due to the shift.

  In the power output apparatus of the present invention in which such a transmission means switches power transmission by switching between two speed ratios, the transmission ratio setting means is configured such that the torque output from the electric motor is within a range of 0 or more. It may be a means for setting a switching point of the gear ratio. In this way, the gear ratio transmission mechanism can be appropriately switched when the torque output from the electric motor has a value of 0 or more so that the gear ratio can be appropriately changed. Can do. That is, the gear ratio can be switched according to the driving state of the electric motor. In this case, the shift transmission means includes two brakes, and the power of the rotating shaft of the electric motor is a first deceleration while the driving shaft is rotating forward and a positive torque is output from the electric motor. From the first transmission ratio transmitted to the drive shaft with a ratio, the second transmission ratio with which the power of the rotating shaft of the motor is transmitted to the drive shaft with a second reduction ratio smaller than the first reduction ratio. When changing, one of the two brakes is switched from off to on with slipping to change the gear ratio, the drive shaft is rotating forward and a positive torque is output from the motor. When the power of the rotating shaft of the motor is changed from the second speed ratio to the first speed ratio from the first speed ratio transmitted to the drive shaft with the second speed reduction ratio in the state where Is the two braces Any of can also be assumed to be a means for changeover of the gear ratio without turning on involve slippage.

  Further, in the power output apparatus of the present invention in which the speed change transmission means switches the speed ratio of the two stages and transmits the power, the speed change ratio setting means should output the rotational speed of the drive shaft and the drive shaft. For the relationship between the torque and the switching point, the required power is set as the product of the rotational speed of the drive shaft and the torque to be output to the drive shaft, and the switching point derived from the relationship is set as the speed ratio switching point. It can also be a means to do. In this way, the gear ratio switching point can be easily set.

  In the power output apparatus of the present invention, the control means is configured such that the set required power and the set required power are covered by power output from the internal combustion engine, and the internal combustion engine is operated with predetermined restrictions. The internal combustion engine, the power drive input / output means, the electric motor, and the shift transmission means may be controlled. In this case, the predetermined restriction may be a restriction that allows the internal combustion engine to operate efficiently. In this way, the energy efficiency of the device can be improved.

  In the power output apparatus of the present invention, the power / power input / output means is connected to three axes of the output shaft, the drive shaft, and the third shaft of the internal combustion engine, and is input / output to any two of the three shafts. It may be a means comprising a three-axis power input / output means for inputting / outputting power to / from the remaining shaft based on the generated power, and a generator for inputting / outputting power to / from the third shaft, A first rotor attached to the output shaft of the internal combustion engine; and a second rotor attached to the drive shaft; and an electromagnetic action between the first rotor and the second rotor. It may be a counter-rotor motor that outputs at least part of the power from the internal combustion engine to the drive shaft with input and output of electric power.

  The automobile of the present invention is a power output apparatus of the present invention according to any one of the above-described aspects, that is, basically a power output apparatus that outputs power to a drive shaft, and includes an internal combustion engine and an output of the internal combustion engine. An electric power input / output means connected to the shaft and the drive shaft for outputting at least part of the power from the internal combustion engine to the drive shaft with input / output of electric power; an electric motor capable of inputting / outputting power; and Shift transmission means for performing transmission of power between the rotating shaft of the electric motor and the drive shaft with a changeable gear ratio; power storage input / output means; power storage means capable of exchanging power with the motor; and Required power setting means for setting required power to charge / discharge the power storage means based on a state; required power setting means for setting required power to be output to the drive shaft based on an operation of an operator; and the setting Requested power and said Transmission ratio setting means for setting a transmission ratio in the transmission transmission means based on the determined required power, and transmission of power between the rotating shaft of the motor and the drive shaft with the set transmission ratio. The internal combustion engine, the power power input / output means, and the electric motor so that the power storage means is charged / discharged by electric power based on the set required power and power based on the set required power is output to the drive shaft. A gist is that a power output device including a control means for controlling the shift transmission means is mounted, and an axle is connected to the drive shaft.

  Since the power output device of the present invention according to any one of the above-described aspects is mounted on the automobile of the present invention, the effect of the power output device of the present invention, for example, within the range where the electric motor can be efficiently driven, An effect similar to the effect of changing the gear ratio, the effect of improving the energy efficiency of the apparatus, and the effect of switching the gear ratio according to the driving state of the motor can be obtained. it can.

The method for controlling the power output apparatus of the present invention includes:
An internal combustion engine; power power input / output means connected to the output shaft of the internal combustion engine and the drive shaft for outputting at least part of the power from the internal combustion engine to the drive shaft with power input / output; An electric motor capable of inputting / outputting power, transmission transmission means for performing transmission of power between the rotating shaft of the electric motor and the drive shaft with a changeable gear ratio, and exchange of electric power with the electric power input / output means and the electric motor. A power output device comprising a power storage means,
(A) Based on the state of the power storage means, setting required power to charge / discharge the power storage means,
(B) setting required power to be output to the drive shaft based on the operation of the operator;
(C) setting a transmission gear ratio in the transmission transmission means based on the set required power and the set required power;
(D) Power is transmitted between the rotating shaft of the electric motor and the drive shaft with the set gear ratio, and the power storage means is charged / discharged by electric power based on the set required power, and the set required power is achieved. The gist of the invention is to control the internal combustion engine, the electric power drive input / output means, the electric motor, and the shift transmission means so that the power based thereon is output to the drive shaft.

  In the control method for the power output device of the present invention, the required power to be charged / discharged for the power storage means is set based on the state of the power storage means, and the required power to be output to the drive shaft is set based on the operation of the operator. Further, a transmission gear ratio is set in the transmission transmission means for performing transmission of power between the rotating shaft of the motor and the drive shaft with a changeable gear ratio based on the set required power and required power. Then, power is transmitted between the rotating shaft of the motor and the drive shaft with the set speed ratio, and the power storage means is charged / discharged by the power based on the set required power, and the power based on the set required power is supplied to the drive shaft. The internal combustion engine, the power drive input / output means, the electric motor, and the transmission transmission means are controlled so as to be output. In other words, the power storage means is shifted based on the required power to be charged / discharged, so that the gear can be shifted within a range where the electric motor can be driven efficiently. As a result, the energy efficiency of the apparatus can be improved.

  In such a control method for a power output apparatus of the present invention, the shift transmission means is a means for transmitting the power by switching between two gear ratios, and step (c) has a torque output from the motor as a value. It may be a step of setting a speed ratio switching point in the speed change transmission means within a positive range near zero. In this way, the gear ratio transmission mechanism can be appropriately switched when the torque output from the electric motor has a value of 0 or more so that the gear ratio can be appropriately changed. In addition, it is possible to easily perform a shift in the shift transmission means, and it is possible to suppress a shock caused by the shift. That is, the gear ratio can be switched according to the driving state of the electric motor.

  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 a configuration of a hybrid vehicle 20 equipped with a power output apparatus as an embodiment of the present invention. As shown in the figure, the hybrid vehicle 20 of the embodiment includes an engine 22, a three-shaft power distribution / integration mechanism 30 connected to a crankshaft 26 as an output shaft of the engine 22 via a damper 28, and power distribution / integration. A motor MG1 capable of generating electricity connected to the mechanism 30, a motor MG2 connected to the power distribution and integration mechanism 30 via a transmission 60, 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 arranged concentrically with the sun gear 31, a plurality of pinion gears 33 that mesh with the sun gear 31 and mesh with the ring gear 32, A planetary gear mechanism is provided that includes a carrier 34 that holds a plurality of pinion gears 33 so as to rotate and revolve, and that performs differential action using the sun gear 31, the ring gear 32, and the carrier 34 as rotational elements. In the power distribution and integration mechanism 30, the crankshaft 26 of the engine 22 is connected to the carrier 34, the motor MG1 is connected to the sun gear 31, and the motor MG2 is connected to the ring gear 32 via the transmission 60. The motor MG1 generates power. When the motor MG1 functions as a motor, the 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 22 input from the carrier 34. And the power from the motor MG1 input from the sun gear 31 are integrated and output to the ring gear 32. The ring gear 32 is mechanically connected to the drive wheels 39a and 39b of the front wheels of the vehicle via a gear mechanism 37 and a differential gear 38. Therefore, the power output to the ring gear 32 is output to the drive wheels 39a and 39b via the gear mechanism 37 and the differential gear 38. Note that the three axes connected to the power distribution and integration mechanism 30 when viewed as a drive system are the crankshaft 26 that is the output shaft of the engine 22 connected to the carrier 34, and the rotation shaft of the motor MG1 that is connected to the sun gear 31. The ring gear shaft 32a as a drive shaft is connected to the sun gear shaft 31a and the ring gear 32 and mechanically connected to the drive wheels 39a and 39b.

  Both the motor MG1 and the motor MG2 are 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 and negative bus shared by the inverters 41 and 42, and the electric power generated by one of the motors MG 1 and MG 2 is supplied to another motor. It can be consumed at. Therefore, battery 50 is charged / discharged by electric power generated from motors MG1 and MG2 or insufficient electric power. Note that the battery 50 is not charged / discharged if the electric power balance is balanced by the motor MG1 and the motor MG2. 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 calculates the rotational speeds Nm1 and Nm2 of the rotors of the motors MG1 and MG2 by a rotational speed calculation routine (not shown) based on signals input from the rotational position detection sensors 43 and 44. 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 transmission 60 connects and disconnects the rotating shaft 48 of the motor MG2 and the ring gear shaft 32a and reduces the rotational speed of the rotating shaft 48 of the motor MG2 to two stages by connecting the both shafts to the ring gear shaft 32a. Configured to communicate. An example of the configuration of the transmission 60 is shown in FIG. The transmission 60 shown in FIG. 2 includes a double-pinion planetary gear mechanism 60a, a single-pinion planetary gear mechanism 60b, and two brakes B1 and B2. The planetary gear mechanism 60a of a double pinion includes an external gear sun gear 61, an internal gear ring gear 62 arranged concentrically with the sun gear 61, a plurality of first pinion gears 63a meshing with the sun gear 61, and the first pinion gear 63a. A plurality of second pinion gears 63b that mesh with the one pinion gear 63a and mesh with the ring gear 62, and a carrier 64 that holds the plurality of first pinion gears 63a and the plurality of second pinion gears 63b so as to rotate and revolve freely. The sun gear 61 can be freely rotated or stopped by turning on and off the brake B1. The single-pinion planetary gear mechanism 60 b includes an external gear sun gear 65, an internal gear ring gear 66 disposed concentrically with the sun gear 65, and a plurality of pinion gears 67 that mesh with the sun gear 65 and mesh with the ring gear 66. And a carrier 68 that holds a plurality of pinion gears 67 so as to rotate and revolve. The sun gear 65 is connected to the rotating shaft 48 of the motor MG2, the carrier 68 is connected to the ring gear shaft 32a, and the ring gear 66 is braked. The rotation can be freely or stopped by turning on and off B2. The double pinion planetary gear mechanism 60a and the single pinion planetary gear mechanism 60b are connected by a ring gear 62 and a ring gear 66, and a carrier 64 and a carrier 68, respectively. The transmission 60 can disconnect the rotating shaft 48 of the motor MG2 from the ring gear shaft 32a by turning off both the brakes B1 and B2, and can turn off the brake B1 and turn on the brake B2 to turn on the rotating shaft 48 of the motor MG2. Is rotated at a relatively large reduction ratio and transmitted to the ring gear shaft 32a (hereinafter, this state is referred to as a Lo gear state), the brake B1 is turned on and the brake B2 is turned off to rotate the rotating shaft 48 of the motor MG2. Is rotated at a relatively small reduction ratio and transmitted to the ring gear shaft 32a (hereinafter, this state is referred to as a Hi gear state). Note that when the brakes B1 and B2 are both turned on, the rotation of the rotary shaft 48 and the ring gear shaft 32a is prohibited.

  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 the 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 from the temperature sensor (not shown) attached to the battery 50, and the like are input. Output to the control unit 70. The battery ECU 52 also calculates the remaining capacity (SOC) based on the integrated value of the charge / discharge current detected by the current sensor in order to manage the battery 50.

  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 is provided with 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 Adrv corresponding to the depression amount of the accelerator pedal 83. The accelerator opening Adrv from the accelerator pedal position sensor 84 to be detected, the brake position BP from the brake pedal position sensor 86 to detect 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. ing. Further, the hybrid electronic control unit 70 outputs a drive signal to actuators (not shown) of the brakes B1 and B2 of the transmission 60 through an output 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 communication ports, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52. Is doing.

  The hybrid vehicle 20 of the embodiment configured in this way calculates the required torque to be output to the ring gear shaft 32a as the drive shaft based on the accelerator opening degree Adrv corresponding to the depression amount of the accelerator pedal 83 by the driver and the vehicle speed V. 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 hybrid vehicle 20 of the embodiment, particularly the operation at the time of drive control accompanied by the switching of the transmission 60 will be described. FIG. 3 is a flowchart illustrating an example of a drive control routine executed by the hybrid electronic control unit 70 according to the embodiment. This routine is repeatedly executed every predetermined time (for example, every 8 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, required battery power Pb *, output limit Wout of battery 50, and the shift state of transmission 60 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 battery required power Pb * is input from the battery ECU 52 by communication from the battery ECU 52 as power to be charged / discharged by the battery ECU 52 based on the remaining capacity (SOC) of the battery 50 or the like. The output limit Wout of the battery 50 is set based on the battery temperature and the remaining capacity (SOC) of the battery 50 and is input from the battery ECU 52 by communication. As the shift state of the transmission 60, a flag to be set when switching the gear state of the transmission 60 is input.

  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. 4 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 rotation speed Nr of the ring gear shaft 32a, the battery required power Pb *, and the loss Loss. The rotational speed Nr of the ring gear shaft 32a can be obtained by multiplying the vehicle speed V by a conversion factor k, or can be obtained by dividing the rotational speed Nm2 of the motor MG2 by the gear ratio Gr of the transmission 60.

  Based on the set required power Pe *, a target rotational speed Ne * and a target torque Te * of the engine 22 are set (step S120). In this setting, the target rotational speed Ne * and the target torque Te * are set based on the operation line for efficiently operating the engine 22 and the required power Pe *. FIG. 5 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, using the set target rotational speed Ne *, the rotational speed Nr (Nm2 / Gr) of the ring gear shaft 32a, and the gear ratio ρ of the power distribution and integration mechanism 30, the target rotational speed Nm1 of the motor MG1 is given by the following equation (1). * Is calculated and a torque command Tm1 * of the motor MG1 is calculated by equation (2) based on the calculated target rotational speed Nm1 * and the current rotational speed Nm1 (step S130). Here, Expression (1) is a dynamic relational expression for the rotating element of the power distribution and integration mechanism 30. FIG. 6 is a collinear diagram showing the dynamic relationship between the rotational speed and torque in the rotating elements of the power distribution and integration mechanism 30. As shown in FIG. 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 multiplying the number Nm2 by the gear ratio Gr of the transmission 60 is shown. Expression (1) can be easily derived by using this alignment chart. The two thick arrows on the R axis indicate that torque Te * output from the engine 22 when the engine 22 is normally operated at the operation point of the target rotational speed Ne * and the target torque Te * is transmitted to the ring gear shaft 32a. Torque and torque that the torque Tm2 * output from the motor MG2 acts on the ring gear shaft 32a via the transmission 60. 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 / (Gr ・ ρ) (1)
Tm1 * = previous Tm1 * + k1 (Nm1 * −Nm1) + k2∫ (Nm1 * −Nm1) dt (2)

  Subsequently, it is determined whether or not to change the gear state of the transmission 60 based on the vehicle speed V, the required torque Tr *, and the battery required power Pb * (step S140). In the embodiment, the determination of the change of the gear state of the transmission 60 is performed by preliminarily determining the relationship among the vehicle speed V, the required torque Tr *, the battery required power Pb * and the gear state and storing it in the ROM 74 as a shift state setting map. When vehicle speed V, required torque Tr *, and battery required power Pb * are given, the corresponding gear state is derived from the map, and this derived gear state is compared with the current gear state. It was. An example of the shift state setting map is shown in FIG. In the figure, a plurality of curves are shift lines that change the state of the gear of the transmission 60 based on the battery required power Pb *, and the power value indicated on the shift line is a battery in which the power for charging the battery 50 is negative. The required power Pb *. For example, when the battery required power Pb * is −6 kW, the gear state of the transmission 60 is the Lo gear state if the intersection of the required torque Tr * and the vehicle speed V is above the −6 kW shift line. If the intersection of Tr * and the vehicle speed V is below the -6 kW shift line, the Hi gear state is established. In the embodiment, the torque output from the motor MG2 is set to the positive side so that the motor MG2 is driven efficiently, that is, the transmission 60 is in the Lo gear state as much as possible and no shift shock is generated. It was set to be in the vicinity of 0. The reason for this will be described later. Further, since it is necessary to drive the motor MG2 below its upper limit rotational speed, when the vehicle speed V is equal to or higher than the vehicle speed Vhi corresponding to a rotational speed slightly lower than the upper limit rotational speed, the required torque Tr * and the battery required power Pb * Regardless, the transmission 60 is assumed to be in the Hi gear state.

  When it is determined that there is no need to switch the gear state of the transmission 60 (step S150), the output limit Wout of the battery 50 and the calculated torque command Tm1 * of the motor MG1 are multiplied by the current rotational speed Nm1 of the motor MG1. A torque limit Tmax as an upper limit of the torque that may be output from the motor MG2 is calculated by the following equation (3) by dividing the deviation from the power consumption (generated power) of the motor MG1 obtained by the rotation speed Nm2 of the motor MG2. At the same time (step S180), a temporary motor torque Tm2tmp as a torque to be output from the motor MG2 is calculated by the equation (4) using the required torque Tr *, the torque command Tm1 *, and the gear ratio ρ of the power distribution and integration mechanism 30 ( Step S190) compares the calculated torque limit Tmax with the temporary motor torque Tm2tmp. Set the smaller as the torque command Tm2 * of the motor MG2 (step S200). By setting the torque command Tm2 * of the motor MG2 in this way, the required torque Tr * output to the ring gear shaft 32a as the drive shaft can be set as a torque limited within the range of the output limit of the battery 50. . Equation (4) can be easily derived from the collinear diagram of FIG. 6 described above.

Tmax ＝ (Wout−Tm1 * ・ Nm1) / Nm2 (3)
Tm2tmp = (Tr * + Tm1 * / ρ) / Gr (4)

  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. The torque commands Tm1 * and Tm2 * for the motors MG1 and MG2 are transmitted to the 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 * performs fuel injection control in the engine 22 such that the engine 22 is operated at an operating point indicated by the target rotational speed Ne * and the target torque Te *. Controls such as 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.

  On the other hand, when it is determined in step S140 that the gear state of the transmission 60 needs to be switched (step S150), the gear state of the transmission 60 is excluded except when the switching process is being executed (step S160). Is instructed to start execution of the process of switching (step S170). When this instruction is given, the hybrid electronic control unit 70 executes a switching processing routine illustrated in FIG. 8 in parallel with the drive control routine. The reason why the switching process execution start instruction is not performed when the switching process is being executed is that a second instruction is not output for the same switching determination. The description of the drive control routine is interrupted, and the switching process will be described below.

  In the switching process routine, first, the switching direction of the gear state of the transmission 60 is determined (step S300). When switching from the Lo gear state to the Hi gear state, first, the motor MG2 after switching using the following equation (5) based on the current rotational speed Nm2 of the motor MG2 and the gear ratios Glo and Ghi of the transmission 60. Is calculated (step S310). Then, the brake B2 is turned off (step S320), and the brake B1 is frictionally engaged (step S330). Then, after waiting for the rotation speed Nm2 of the motor MG2 to reach the vicinity of the rotation speed Nm2 * after switching (steps S340 and S350), the brake B1 is completely turned on (step S360), and the transmission 60 used in the drive control is The gear ratio Ghi of the Hi gear is set to the gear ratio Gr (step S370), and the switching process routine is ended. FIG. 9 shows an example of a collinear diagram of the transmission 60. In the figure, the S1 axis indicates the rotational speed of the sun gear 61 of the double pinion planetary gear mechanism 60a, and the R1 and R2 axes indicate the rotational speeds of the ring gears 62 and 66 of the double pinion planetary gear mechanism 60a and the single pinion planetary gear mechanism 60b. The C1 and C2 axes indicate the rotational speeds of the carriers 64 and 68 of the double pinion planetary gear mechanism 60a and the single pinion planetary gear mechanism 60b, which are the rotational speeds of the ring gear shaft 32a, and the S2 axis indicates the rotational speed of the motor MG2. The rotational speed of the sun gear 65 of the single-pinion planetary gear mechanism 60b is shown. As shown in the figure, in the Lo gear state, the brake B2 is on and the brake B1 is off. When the brake B2 is turned off from this state, the motor MG2 is disconnected from the ring gear shaft 32a, and since positive torque is output from the motor MG2, its rotational speed tends to increase. Here, when the brake B1 is frictionally engaged, the rotational speed Nm2 of the motor MG2 decreases. Then, when the rotational speed Nm2 of the motor MG2 becomes close to the rotational speed Nm2 * in the Hi gear state, the brake B1 can be switched from the friction engagement to the Hi gear state by completely turning on. Thus, the shift shock can be suppressed by turning on and off the brake B1 and the brake B2.

  Nm2 * ＝ Nm2 ・ Ghi / Glo (5)

On the other hand, when switching from the state of the Hi gear to the state of the Lo gear, first, after switching using the following equation (6) based on the current rotational speed Nm2 of the motor MG2 and the gear ratios Glo and Ghi of the transmission 60. The rotational speed Nm2 * of the motor MG2 is calculated (step S380). Then, the brake B1 is turned off (step S390), and it waits for the rotational speed Nm2 of the motor MG2 to reach the vicinity of the rotational speed Nm2 * after switching (steps S400 and S410), and the brake B2 is turned on (step S420). The gear ratio Glo of the Lo gear is set to the gear ratio Gr of the transmission 60 used for drive control (step S430), and the switching process routine is ended.
As shown in FIG. 9, in the state of the Hi gear, the brake B1 is on and the brake B2 is off. When the brake B1 is turned off from this state, the motor MG2 is disconnected from the ring gear shaft 32a. As described above, since the positive torque is output from the motor MG2, the number of rotations tends to increase. To do. Therefore, it is possible to switch to the Lo gear state by turning on the brake B2 after waiting until the rotation number Nm2 of the motor MG2 is close to the rotation number Nm2 * of the Lo gear state.

  Nm2 * ＝ Nm2 ・ Glo / Ghi (6)

  As described above, when the transmission 60 is switched from the Lo gear state to the Hi gear state while the positive torque is output from the motor MG2, it is necessary to frictionally engage the brake B1. Therefore, in the hybrid vehicle 20 of the embodiment, the brake B1 uses a brake capable of friction engagement and an actuator capable of adjusting the engagement force, and the brake B2 uses a brake that can be simply turned on and off. An actuator in which the engagement force cannot be adjusted can be used. Further, the gear state of the transmission 60 is preferably switched quickly from the Hi gear state to the Lo gear state considering the response when the driver depresses the accelerator pedal 83 greatly. . Therefore, it is preferable that the frictional engagement of the brake is not involved in switching from the Hi gear state to the Lo gear state. The shift line of the embodiment is set so that the torque output from the motor MG2 is close to the value 0 on the positive side so as to respond to the configuration of the brake B1 and the brake B2 and the quick request of the shift. When the torque output from the motor MG2 is a negative value, when switching from the Lo gear state to the Hi gear state, the brake B2 is turned off, and the rotational speed Nm2 of the motor MG2 is the rotational speed Nm2 * in the Hi gear state. When switching from the Hi gear state to the Lo gear state, the brake B1 is turned off and the brake B2 is frictionally engaged, and the rotational speed Nm2 of the motor MG2 is set to the Lo gear. The brake B2 is completely turned on after waiting for the rotation speed Nm2 * in the state of. Therefore, when the gear state of the transmission 60 is switched without considering the sign (positive or negative) of the torque output from the motor MG2, both the brake B1 and the brake B2 are configured as brakes capable of friction engagement and the actuators thereof. It is also necessary to be able to adjust the engagement force. The torque output from the motor MG2 is negative during high-speed cruising operation that requires relatively high speed and low torque, and the torque output from the motor MG2 is positive otherwise. From this, it can be understood that it is preferable to switch the gear state of the transmission 60 when the torque output from the motor MG2 is on the positive side and in the vicinity of the value 0.

  Even while such switching processing is being executed, the drive control routine illustrated in FIG. 3 is executed. In the drive control routine, while the switching process is being performed, the torque command Tm2 * of the motor MG2 is set as not being switched. However, the switching process is performed when the torque command Tm2 * is near zero. And the time required for the switching process is relatively short (for example, about 200 to 400 msec). Therefore, even if the torque command Tm2 * of the motor MG2 is not set in consideration of switching, there is almost no shift shock. Does not occur.

  According to the hybrid vehicle 20 of the embodiment described above, since the gear state of the transmission 60 is set based on the vehicle speed V, the required torque Tr *, and the battery required power Pb *, the efficiency of the motor MG2 is as good as possible. The gear state of the transmission 60 can be switched more within the range. Further, since the gear state of the transmission 60 is switched when the torque output from the motor MG2 is close to 0, a shock (shift shock) that can occur when the transmission 60 is switched can be suppressed. Since the gear state is switched as much as possible to make the transmission 60 in the Lo gear state, the motor MG2 can be driven efficiently, thereby improving the energy efficiency of the entire vehicle. Furthermore, since the gear state of the transmission 60 is switched when the torque output from the motor MG2 is positive, the brake B1 uses a brake capable of friction engagement and an actuator capable of adjusting its engagement force. For B2, a brake that can be simply turned on and off is used, and an actuator whose engagement force cannot be adjusted can be used. Therefore, both the brake B1 and the brake B2 can be configured as a brake capable of frictional engagement, and the actuator can be configured in a simpler manner than the case where a brake capable of adjusting the engagement force is used. As a result, the gear state of the transmission 60 can be more appropriately switched according to the driving state of the motor MG2.

  In the hybrid vehicle 20 of the embodiment, the gear state of the transmission 60 is switched when the torque output from the motor MG2 is on the positive side and near the value 0, but the torque output from the motor MG2 is the value 0 on the negative side. The gear state of the transmission 60 may be switched when near, or the gear state of the transmission 60 may be switched when the torque output from the motor MG2 is not near zero on the positive side.

  In the hybrid vehicle 20 of the embodiment, the transmission 60 that can change gears with two speeds of Hi and Lo is used. However, the speed of the transmission 60 is not limited to two, but three or more. It is good also as this gear stage.

  In the hybrid vehicle 20 of the embodiment, the power of the motor MG2 is changed by the transmission 60 and output to the ring gear shaft 32a. However, as illustrated in the hybrid vehicle 120 of the modified example of FIG. Is shifted by a transmission 60 and connected to an axle (an axle connected to wheels 39c and 39d in FIG. 10) different from an axle (an axle to which drive wheels 39a and 39b are connected) to which a ring gear shaft 32a is connected. It is good.

  In the hybrid vehicle 20 of the embodiment, the power of the engine 22 is output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 39a and 39b via the power distribution and integration mechanism 30, but the modified example of FIG. The hybrid vehicle 220 includes an inner rotor 232 connected to the crankshaft 26 of the engine 22 and an outer rotor 234 connected to a drive shaft that outputs power to the drive wheels 39a and 39b. A counter-rotor motor 230 that transmits a part of the power to the drive shaft and converts the remaining power into electric power may be provided.

  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 equipped with a power output apparatus as an embodiment of the present invention. 4 is an explanatory diagram illustrating an example of a configuration of a transmission 60. FIG. 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 explanatory drawing which shows an example of the map for request | requirement braking torque setting. It is explanatory drawing which shows a mode that an example of the operating line of the engine 22, and target rotational speed Ne * and target torque Te * are set. FIG. 4 is an explanatory diagram showing an example of a collinear diagram for dynamically explaining rotational elements of a power distribution and integration mechanism 30; It is explanatory drawing which shows an example of the map for gear shifting state setting. It is a flowchart which shows an example of the switching process routine performed by the electronic control unit for hybrids 70 of an Example. 4 is an explanatory diagram illustrating an example of a collinear diagram of the transmission 60. FIG. 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.

Explanation of symbols

20, 120, 220 Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 26 crankshaft, 28 damper, 30 power distribution integration mechanism, 31 sun gear, 31a sun gear shaft, 32 ring gear, 32a ring gear shaft, 33 Pinion gear, 34 carrier, 37 gear mechanism, 38 differential gear, 39a, 39b, 39c, 39d drive wheel, 39e, 39f driven wheel, 40 electronic control unit for motor (motor ECU), 41, 42 inverter, 43, 44 rotational position Detection sensor, 48 rotary shaft, 50 battery, 52 battery electronic control unit (battery ECU), 54 power line, 60 transmission, 60a double pinion planetary gear mechanism, 60b single pinion planetary gear mechanism, 61, 65 Gear, 62, 66 Ring gear, 63a First pinion gear, 63b Second pinion gear, 64, 68 Carrier, 67 pinion gear, 70 Electronic control unit for hybrid, 72 CPU, 74 ROM, 76 RAM, 80 Ignition switch, 81 Shift lever, 82 Shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor, 88 vehicle speed sensor, 230 rotor motor, 232 inner rotor 234 outer rotor, MG1, MG2 motor, B1, B2 brake.

Claims (12)

A power output device that is mounted on an automobile and outputs power to a drive shaft connected to the axle ,
An internal combustion engine;
Power power input / output means connected to the output shaft of the internal combustion engine and the drive shaft, and outputting at least part of the power from the internal combustion engine to the drive shaft with input and output of power and power;
An electric motor that can input and output power;
Shift transmission means for performing transmission of power between the rotating shaft of the electric motor and the drive shaft with a changeable gear ratio;
A power storage means capable of exchanging power with the electric power drive input / output means and the electric motor;
Vehicle speed detection means for detecting the vehicle speed;
Required power setting means for setting required power to charge / discharge the power storage means based on the state of the power storage means;
A required torque setting means for setting a torque demand to be output to said drive shaft, based on the operator's operation,
A transmission ratio setting means for setting a transmission ratio in the transmission transmission means based on the set required power, the set required torque, and the detected vehicle speed ;
Power is transmitted between the rotating shaft of the electric motor and the drive shaft with the set gear ratio, and the power storage means is charged / discharged by the electric power based on the set required power, and the set required torque is obtained. Control means for controlling the internal combustion engine, the power drive input / output means, the electric motor, and the shift transmission means so that a torque based on the torque is output to the drive shaft;
A power output device comprising: The power output device according to claim 1,
The shift transmission means is means for transmitting the power by switching between two speed ratios,
The gear ratio setting means is means for setting a gear ratio switching point in the gear transmission means.   The power output apparatus according to claim 2, wherein the speed ratio setting means is a means for setting the speed ratio switching point so that the torque output from the electric motor is close to a value of zero.   The power output apparatus according to claim 2 or 3, wherein the speed ratio setting means is a means for setting the speed ratio switching point within a range where the torque output from the electric motor has a value of 0 or more.   The shift transmission means includes two brakes, and the power of the rotating shaft of the electric motor has a first reduction ratio in a state where the driving shaft is rotating forward and positive torque is being output from the electric motor. When changing from the first speed ratio transmitted to the drive shaft to the second speed ratio transmitted to the drive shaft with a second speed ratio that is smaller than the first speed reduction ratio. In one of the two brakes, one of the two brakes is turned on with slipping to switch the gear ratio, the drive shaft is rotating forward and the motor is outputting a positive torque. When the power of the rotating shaft of the electric motor changes from the second speed ratio to the first speed ratio from the first speed ratio transmitted to the drive shaft with the second speed reduction ratio in the state, the second speed One of the two brakes There power output apparatus according to claim 4 wherein the means for switching the speed change ratio without turning on involve slippage. The control means is configured so that the set required torque , the detected vehicle speed, and the set required power are covered by power output from the internal combustion engine and the internal combustion engine is operated with predetermined restrictions. 6. The power output apparatus according to claim 1, which is means for controlling the internal combustion engine, the power drive input / output means, the electric motor, and the shift transmission means. The power output apparatus according to claim 6 , wherein the predetermined restriction is a restriction that allows the internal combustion engine to operate efficiently. The power power input / output means is connected to the three shafts of the output shaft, the drive shaft, and the third shaft of the internal combustion engine, and the remaining shaft based on the power input / output to any two of the three shafts. The power output apparatus according to any one of claims 1 to 7 , further comprising: a three-axis power input / output means for inputting / outputting power to / from the power generator and a generator for inputting / outputting power to / from the third shaft. The power drive input / output means includes a first rotor attached to the output shaft of the internal combustion engine and a second rotor attached to the drive shaft, and the first rotor and the second rotor. 9. A power output apparatus according to claim 1 , wherein the power output apparatus is a counter-rotor motor that outputs at least a part of power from the internal combustion engine to the drive shaft with input / output of electric power by electromagnetic action with the rotor. . An automobile equipped with the power output device according to claim 1 . An internal combustion engine, and an electric power / power input / output means connected to the output shaft and the drive shaft of the internal combustion engine for outputting at least part of the power from the internal combustion engine to the drive shaft with input / output of electric power and power; An electric motor capable of inputting / outputting power; transmission transmission means for performing transmission of power between a rotating shaft of the electric motor and the drive shaft with a changeable gear ratio; and exchange of electric power with the electric power input / output means and the electric motor. And a power storage means capable of controlling a power output device mounted on an automobile ,
(A) Based on the state of the power storage means, setting required power to charge / discharge the power storage means,
(B) setting a required torque to be output to the drive shaft based on the operation of the operator;
(C) setting a transmission gear ratio in the transmission transmission means based on the set required power, the set required torque and the vehicle speed ;
(D) Power is transmitted between the rotating shaft of the motor and the drive shaft with the set gear ratio, and the power storage means is charged / discharged by the electric power based on the set required power, and the set required torque is achieved . A control method for a power output device that controls the internal combustion engine, the power power input / output means, the electric motor, and the shift transmission means so that a torque based on the power is output to the drive shaft. A method for controlling a power output apparatus according to claim 11 ,
The shift transmission means is means for transmitting the power by switching between two speed ratios,
The step (c) is a step of setting a speed ratio switching point in the speed change transmission means within a positive range in which the torque output from the electric motor has a value near zero.

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