JP4165431B2 - Control device for hybrid electric vehicle - Google Patents

Description

  The present invention relates to driving force control of a hybrid electric vehicle including an internal combustion engine and a driving motor.

  In a hybrid electric vehicle including a generator driven by an internal combustion engine and an electric motor that drives the vehicle with the generated power of the generator, in order to reduce the capacity of the battery, the power consumption of the electric motor and the generated power of the generator It is desirable to control the engine output so that.

  When the vehicle accelerates, part of the engine output is used to increase the rotational speed of the engine itself and the generator, so the generator is required to drive the electric motor after the command to increase the engine output is issued. A time lag occurs until the rotation speed at which sufficient power can be supplied is reached. By supplying power from the battery to the generator and accelerating the rotation of the generator and the engine, this time lag can be reduced. At the same time, electric power is supplied to the electric motor from the battery until the rotational speed at which the generator can supply the necessary electric power is reached. However, if power is supplied from the battery to the generator, it is inevitable that the power supply from the battery to the electric motor is reduced.

  Therefore, even if battery power is supplied to the generator to reduce the time lag, the acceleration performance of the vehicle is not necessarily improved.

Therefore, in order to suppress the consumption of battery power during acceleration, it has been proposed to limit the output of the electric motor when the generated power of the generator is lower than the required generated power (see Patent Document 1).
Japanese Patent Laid-Open No. 2001-292501

  However, if the output of the electric motor is limited, the rate of increase of the rotational speed of the electric motor, that is, the acceleration of the vehicle is performed only slowly. Although the conventional technology contributes to the suppression of battery power consumption, it may become an impediment to the acceleration performance of the vehicle.

  An object of the present invention is to optimize the acceleration performance of a hybrid electric vehicle under a limited storage capacity.

A driving force control apparatus for a hybrid electric vehicle according to the present invention includes an accelerator pedal, an engine that consumes fuel and outputs rotational torque to an output shaft, and generates electric power according to the rotational torque of the output shaft of the engine. Is electrically connected to the first motor that transmits rotational torque to the engine in response to the second motor, the second motor that generates vehicle driving torque in response to the supplied power, and the first motor and the second motor, In a hybrid vehicle comprising a power storage device that supplies power to the first motor and the second motor and stores power generated by the first motor, the vehicle according to the amount of depression of the accelerator pedal Means for setting the target drive torque of the power supply, means for supplying power corresponding to the target drive torque from the power storage device to the second motor, and output power of the power storage device. Means for subtracting the power supplied to the second motor to calculate the power available for supply to the first motor, means for calculating the target engine speed based on the target drive torque, and supply to the first motor When the available power is a positive value and the target engine speed exceeds the engine speed, the first motor receives power from the power storage device within a range that does not exceed the power that can be supplied to the first motor. Means for supplying;
Is provided.

  As the accelerator pedal is depressed, the power storage device supplies power to the second motor to accelerate the vehicle. On the other hand, the power that can be supplied to the first motor is calculated by subtracting the power that is supplied to the second motor from the power that can be output from the power storage device. When the power that can be supplied to the first motor is a positive value and the target engine speed exceeds the engine speed, the first motor is fed to the range that does not exceed the power that can be supplied to the first motor. The first motor accelerates the engine by supplying power from the power storage device. The acceleration of the engine by the first motor accelerates the engine speed to reach the target speed. Since the surplus power is used for accelerating the engine after securing the power for driving the vehicle, the acceleration performance of the hybrid electric vehicle is optimized under the limited storage capacity.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  Referring to FIG. 1, a series hybrid electric vehicle includes an internal combustion engine 1, an AC generator / motor 2 directly connected to the internal combustion engine 1, and an alternating current that rotationally drives drive wheels 5 using the power generated by the generator / motor 2. And a power train composed of a power storage device 6 interposed in an electric circuit connecting the generator / motor 2 and the electric motor 3.

  Generator / motor 2 corresponds to the claimed first motor and electric motor 3 corresponds to the claimed second motor.

  The power storage device 6 includes a battery and a converter / inverter that converts direct current to alternating current.

  The electric motor 3 is coupled to the drive wheel 5 via the final gear 4. The electric motor 3 may be constituted by a motor having a generator function for regenerating rotational energy of the drive wheels 5 when the vehicle is decelerated.

  The control device includes an engine controller 7, an inverter 8, a battery controller 10, an inverter 11, and an integrated controller 9 for controlling the power train.

  The controllers 7, 9 and 10 are each composed of a microcomputer having a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM) and an input / output interface (I / O interface).

  Each controller can be constituted by a plurality of microcomputers. Conversely, a plurality of controllers can be configured by a single microcomputer.

  The output torque of the internal combustion engine 1 is adjusted through the opening of the electronic throttle, the fuel injection amount, and the ignition timing. The engine controller 7 adjusts these according to the engine torque command value output from the integrated controller 9.

  Since the generator / motor 2 is directly connected to the internal combustion engine 1, the rotational speed of the generator / motor 2 is equal to the rotational speed of the internal combustion engine 1. The inverter 8 adjusts the torque of the generator / motor 2 by vector control based on the command signal from the integrated controller 9.

  The inverter 8 also has a function of detecting the actual rotational speed of the generator / motor 2 and the actual generated power and inputting a corresponding signal to the integrated controller 9.

  The integrated controller 9 calculates a torque command value for the generator / motor 2 so that the actual rotation speed of the generator / motor 2 matches the target rotation speed, and outputs a corresponding signal to the inverter 8. The generator controller 8 controls the actual rotational speed of the generator / motor 2 to the target rotational speed by controlling the generated power of the generator / motor 2 based on the torque command value, in other words, the rotational resistance.

  The battery controller 10 calculates the state of charge (SOC) of the battery, the input power and the output power based on the charge / discharge voltage and current of the battery of the power storage device 6, and outputs signals corresponding to the calculation results to the integrated controller 9 To enter.

  The inverter 11 adjusts the output torque of the electric motor 3 by vector control based on the motor torque command value output from the integrated controller 9. The inverter 11 also has a function of detecting the actual driving power of the electric motor 3 and inputting a corresponding signal to the integrated controller 9.

  The control device further includes an accelerator pedal depression amount sensor 12A that detects the depression amount APS of the accelerator pedal 12 included in the vehicle, and a vehicle speed sensor 13 that detects the vehicle speed. The detection data of these sensors is input to the integrated controller 9 as a signal.

  Next, a control routine for the output torque of the engine 1, the generated torque of the generator / motor 2 and the drive torque of the electric motor 3 executed by the integrated controller 9 under the above configuration will be described. This routine is executed at intervals of 10 milliseconds when the vehicle power switch is on.

  First, an outline of the control will be described.

  When the vehicle is accelerated by depressing the accelerator pedal 12, there is a time lag from when the output increase of the engine 1 is commanded until the rotation of the generator / motor 2 coupled to the engine 1 actually increases. This is because a part of the output of the engine 1 is first consumed to increase the rotation of the engine 1 and the generator / motor 2 overcoming the inertial resistance.

  At this time, if the generator / motor 2 is driven as an electric motor, the rotation of the engine 1 and the generator / motor 2 is accelerated, and the rotational speed of the engine 1, that is, the generated power of the generator / motor 2 can be increased early. However, the power storage capacity of the power storage device 6 is limited, and if the amount of power supplied to the electric motor 3 is reduced for power supply to the generator / motor 2, the acceleration performance of the vehicle will be reduced.

  Therefore, this control device controls the operation of the engine 1, the generator / motor 2 and the electric motor 3 in accordance with the power supply capability of the power storage device 6 so that the acceleration performance of the vehicle is optimized. The integrated controller 9 sets the target rotational speed of the generator / motor 2 according to the vehicle speed and accelerator pedal depression amount APS, and if there is a margin in the power supply capacity of the power storage device 6, the difference between the target rotational speed and the actual rotational speed is set. Depending on the condition, power is supplied to generator / motor 2.

  Next, this control will be described in detail with reference to FIG.

  It should be noted that the blocks B15-B32 shown in this figure show the functions of the integrated controller 9 as virtual units and do not mean physical existence.

  First, in block B15, the integrated controller 9 searches for a map of axle drive torque stored in the ROM in advance based on the accelerator pedal depression amount APS detected by the accelerator pedal depression amount sensor 12A and the vehicle speed detected by the vehicle speed sensor 13. To set the target axle drive torque Tsd. The map gives a larger target axle driving torque Tsd as the accelerator pedal depression amount APS is larger, and a larger target axle driving torque Tsd as the vehicle speed is smaller.

  The integrated controller 9 calculates the output torque command value Tsm of the electric motor 3 by dividing the target axle driving torque Tsd by the reduction ratio Gf of the final gear 4 in block B16. The integrated controller 9 controls the output torque of the electric motor 3 by vector control by outputting the output torque command value Tsm to the inverter 11.

  On the other hand, in block B17, the integrated controller 9 calculates the target drive output Psd of the vehicle by multiplying the target axle drive torque Tsd by the axle rotational speed. The axle rotation speed is obtained by multiplying the vehicle speed by a certain coefficient.

  The integrated controller 9 calculates the target generated power Pgen by adding the energy loss accompanying the operation of the electric motor 3 to the target drive output Psd in block B18. Here, the target generated power Pgen is equal to the target supply power to the electric motor 3. The energy loss due to the operation of the electric motor 3 changes according to the output torque and the rotation speed of the electric motor 3. Therefore, a map in which energy loss is experimentally determined using the output torque and rotation speed of the electric motor 3 as parameters is created in advance and stored in the ROM of the integrated controller 9. In block B18, the integrated controller 9 searches this map from the output torque command value Tsm obtained in block 16B and the actual rotational speed of the electric motor 3 detected by the inverter 8, and calculates the energy loss due to the operation of the electric motor 3. Ask.

  The integrated controller 9 calculates the target engine output Peng by adding the energy loss accompanying the operation of the generator / motor 2 to the target generated power Pgen in block B19. The energy loss associated with generator / motor 2 operation is estimated as follows.

  When the generator / motor 2 is driven by the engine 1 to generate electricity, the energy loss of the generator / motor 2 in the operating state where the fuel consumption of the engine 1 is minimized with respect to various generated power is experimentally determined. Create a map. This map is stored in advance in the ROM of the integrated controller 9, and the integrated controller 9 obtains the energy loss of the generator / motor 2 with reference to this map from the target generated power Pgen. Alternatively, the energy loss is measured for each generated power and rotational speed of the generator / motor 2 and a map is created. This map is stored in advance in the ROM of the integrated controller 9, and the integrated controller 9 obtains energy loss based on the target generated power Pgen and the rotation speed of the generator / motor 2 detected by the inverter 8.

  The integrated controller 9 calculates the engine torque command value Ts by dividing the target engine output Peng by the engine speed in block B20. The engine rotation speed is equal to the rotation speed of the electric motor 2 detected by the inverter 8. The integrated controller 9 outputs the engine torque command value Ts to the engine controller 7.

  The integrated controller 9 refers to the minimum fuel consumption map having the characteristics shown in the figure based on the target engine output Peng in block B21, and obtains the target rotational speed for achieving the target engine output Peng with the minimum fuel consumption. The obtained target rotational speed of engine 1 is output to block B22 as generator target rotational speed Ns.

  The integrated controller 9 calculates the difference between the generator target rotational speed Ns and the rotational speed of the generator / motor 2 detected by the inverter 8 in block B22.

  The integrated controller 9 calculates the temporary generator torque command value Tg ′ so that the speed difference decreases in block B23. The PID control method used for feedback control is applied to calculate the temporary generator torque command value Tg '.

  On the other hand, the integrated controller 9 reads the power that can be output from the power storage device 6 that is input from the battery controller 10 in block B24 and the actual power that is generated from the generator / motor 2 that is input from the inverter 8 in block B25. The integrated controller 9 limits the lower limit of the actual generated power to zero by so-called select high control in block B26.

  In block B27, the integrated controller 9 subtracts the generator / motor 2 target generated power Pgen calculated in block B18 from the sum of the output possible voltage of the power storage device 6 and the actual generated power of the generator / motor 2 to obtain the surplus. Calculate power Prem.

  The reason for limiting the lower limit of actual power generation to zero in block B26 is as follows.

  When generator / motor 2 is driven as an electric motor, the actual generated power read in block B25 is a negative value. This negative generated power is motor drive power supplied from the power storage device 6 to the generator / motor 2. The outputtable power of the power storage device 6 read by the integrated controller 9 in block B24 is a value obtained by subtracting this drive power. Therefore, in block B27, only the generated power of generator / motor 2 is input as a positive value, and the driving power for driving generator / motor 2 as an electric motor is not input.

  The actual power generated by generator / motor 2 can be obtained by directly measuring the AC power generated by generator / motor 2 or by subtracting the generator loss from the product of generator / motor 2's rotational torque and rotational speed.

  In block B28, the integrated controller 9 regulates the lower limit value of the surplus power Prem to zero by the select high control by the select high control. The value after the limit is the generator / motor usable power Pgl.

  In the block B30, the integrated controller 9 divides the usable power Pgl of the generator / motor 2 by the actual rotational speed of the generator / motor 2 input from the inverter 8 to drive the generator / motor 2 as an electric motor. Calculate the output possible torque Tgl.

  The usable power Pgl and the outputable torque Tgl of the generator / motor 2 mean the electric power that can drive the generator / motor 2 as an electric motor and the output torque obtained as a result. When the generator / motor 2 is driven as an electric motor within this range, the rotations of the engine 1 and the generator / motor 2 can be accelerated without exceeding the output power of the power storage device 6.

  On the other hand, the integrated controller 9 regulates the upper limit of surplus power Prem to zero by so-called select low control in block B29. The absolute value after regulation is the required generation power Pgm when the generator / motor 2 is operated as a generator.

  In block B31, the integrated controller 9 divides the required generated power Pgm by the actual rotational speed of the generator / motor 2 to calculate the required generated torque Tgm of the generator / motor 2.

  The required power generation Pgm and the required power generation torque Tgm of the generator / motor 2 represent the shortage of power that can be supplied at this time and the torque conversion value for the power required to achieve the target axle drive torque Tsd. .

  According to the processing algorithm of block B28 and block B29, if the usable power Pgl of generator / motor 2 is a non-zero value, the required generated power Pgm of generator / motor 2 is zero, and the generator / motor 2 demand When the generated power Pgm is a value other than zero, the usable power Pgl of the generator / motor 2 is zero.

  In block B32, the integrated controller 9 corrects the temporary generator torque command value Tg 'based on the output possible torque Tgl and the required power generation torque Tgm in the following manner, and calculates the generated torque command value Tg of the generator / motor 2. To do.

  First, when the outputtable torque Tgl is a value other than zero, the outputtable torque Tgl is set as the generator / motor 2 generated torque command value Tg. In this case, electric power is supplied from the power storage device 6 to the generator / motor 2, and the generator / motor 2 generates torque as a motor and transmits it to the engine 1.

  If the outputtable torque Tgl is zero, the larger of the provisional generator torque command value Tg 'and the required power generation torque Tgm is used as the generator / motor 2 generated torque command value Tg. In this case, the generated torque command value Tg of the generator / motor 2 is output as a negative value, and the generator / motor 2 generates power with the input torque from the engine 1 as a generator.

  When the drive torque command value Tg is a positive value, the inverter 8 supplies power corresponding to the drive torque command value Tg to the generator / motor 2 to drive the generator / motor 2 as an electric motor. When the drive torque command value Tg is a negative value, the inverter 8 causes the motor / generator 2 so that the generator / motor 2 receives the torque equal to the absolute value of the drive torque command value Tg from the engine 1 and generates power. Adjust the rotation resistance. When the drive torque command value Tg is zero, there is no power shortage and no correction is made.

  According to the above control, first, electric power corresponding to the output torque command value Tsm is supplied to the electric motor 3 in the block B16, and the output of the internal combustion engine 1 is output based on the engine torque command value Ts corresponding to the output torque command value Tsm in the block B20. Torque is controlled.

  On the other hand, in block B27, the surplus power Prem is obtained by subtracting the target generated power Pgen of the generator / motor 2 from the actual generated power of the generator / motor 2 and the output power of the power storage device 6. The generator / motor 2 is operated as a generator or a motor via the inverter 8 by the drive torque command value Tg corresponding to the sign of the surplus power Prem.

  Therefore, in accelerating the vehicle, first, electric power corresponding to the target driving force is supplied to the electric motor 3, and then surplus electric power is supplied to the generator / motor 2 as necessary, so that the rotation of the generator / motor 2 and the engine 1 is performed. Used for acceleration. Therefore, optimal acceleration performance of the vehicle is realized under given power supply conditions.

  In this control, preferably, the required power generation torque Tgm calculated in the block B31 is limited so as not to exceed the output torque of the engine 1. Alternatively, in block B16, when calculating the output torque command value Tsm of the electric motor 3, the amount of change from the command value Tsmn-1 when the previous routine was executed is limited according to the power that can be output from the power storage device 6. Is provided. Instead of the power that can be output from the power storage device 6, a power storage state of the power storage device 6 and a limit using the temperature of the power storage device 6 as parameters may be provided. Limiting the amount of change is realized by limiting the amount of change per unit time or by adding a smoothing process to the output torque command value Tsm.

  The reason for limiting the amount of change in the output torque command value Tsm of the electric motor 3 is as follows.

  In the routine shown in FIG. 2, the output torque command value Tsm to the electric motor 3 in block B16 is output prior to the output of the generator / motor 2 power generation torque command value Tg in block B32. For this reason, if there is no restriction on the amount of change in the output torque command value Tsm to the electric motor 3, all the electric power that can be output from the power storage device 6 is supplied to the electric motor 3, and the power supplied to the generator / motor 2 is insufficient. there is a possibility.

  In this state, the increase in the rotational speed of the engine 1 and the generator / motor 2 depends only on the blow-up of the engine 1 due to the engine torque command value Ts, and the increase in the rotational speed is likely to be delayed.

  Limiting the amount of change in the output torque command value Tsm can prevent a sudden increase in power consumption of the electric motor 3 immediately after the accelerator pedal 12 is depressed. In the meantime, surplus power can be supplied to the generator / motor 2 to increase the rotational speed of the engine 1 and the generator / motor 2.

  Next, a second embodiment of the present invention in which the present invention is applied to a parallel hybrid electric vehicle will be described with reference to FIG. 3-9.

  Referring to FIG. 3, the parallel hybrid electric vehicle according to this embodiment includes a power train including an internal combustion engine 1, a generator / motor 2, and a planetary gear mechanism 14 that mechanically links the electric motor 3 to each other. A rotation speed sensor 19 that detects the rotation speed of the engine 1 is also provided. Other configurations related to hardware are the same as those in the first embodiment.

  Referring to FIG. 5, the planetary gear mechanism 14 rotates the sun gear 16, a ring gear 17 coaxially disposed outside the sun gear 16, a plurality of planet gears 15 meshing with the sun gear 16 and the ring gear 17, and the planet gear 15. And a carrier 18 that supports the sun gear 16 so as to be capable of revolving.

  Sun gear 16 is coupled to generator / motor 2. Ring gear 17 is coupled to drive wheel 5 via final gear 4. Carrier 18 is coupled to engine 1.

  With this structure, the rotational torque of the engine 1 is transmitted not only to the generator / motor 2 via the sun gear 16 but also to the drive wheels 5 via the ring gear 17.

  Under this planetary gear mechanism 14, the relationship among the rotational speeds of the engine 1, the generator / motor 2 and the electric motor 3 is defined as shown in FIG. Α and β in the figure correspond to the gear ratio α / β between the sun gear 16 and the ring gear 17. This figure defines the relationship and range of the rotational speed that the engine 1 and the generator / motor 2 can take with respect to a certain rotational speed of the electric motor 3, and controls the rotational speed of the generator / motor 2 by controlling the rotational speed of the generator / motor 2. , Indicating that the rotational speed of engine 1 is controlled. That is, the planetary gear mechanism 14 functions as a transmission that changes the ratio of the rotational speed of the engine 1 and the rotational speed of the final gear 4 according to the rotational speed of the generator / motor 2.

  With reference to FIG. 4, the control of the output torque of the engine 1, the generated torque of the generator / motor 2 and the drive torque of the electric motor 3 executed by the integrated controller 9 according to this embodiment will be described. This routine corresponds to the control of FIG. 2 according to the first embodiment, and is executed at intervals of 10 milliseconds when the power switch of the vehicle is on.

  In this embodiment, blocks B16 and B18 are omitted and blocks B41 to B44 are added to the control according to the first embodiment of FIG.

  The parallel hybrid electric vehicle differs from the series hybrid electric vehicle in that the engine output is distributed to the drive wheels 5. In the first embodiment, the surplus power Prem is calculated based on the target generated power Pgen. However, in this embodiment, the surplus power Prem is calculated based on the power scheduled to be consumed by the electric motor 3. In the first embodiment, the entire amount of drive torque of the drive wheels 5 is supplied from the electric motor 3, but in this embodiment the output torque of the engine 1 is also transmitted to the drive wheels 5, so The required output torque is reduced. Correspondingly, surplus power Prem that can be supplied from power storage device 6 to generator / motor 2 increases.

  The integrated controller 9 calculates an estimated value of the engine torque input to the axle in block B41. This estimated value is obtained by subtracting the generator / motor 2 drive torque from the engine output torque. The engine output torque is obtained by filtering the engine torque command value Tp described later. However, the engine torque command value Tp is not a value to be calculated from now on, but a value output by the previous or previous routine execution. Alternatively, it is possible to detect the intake air amount of the engine 1 and obtain the engine output torque from the intake air amount. The drive torque command value Tg described later is used as the drive torque of generator / motor 2. This value is the value that was output during the previous routine execution.

  After calculating the target axle drive torque Tpd in block B15, the integrated controller 9 subtracts the estimated value of the engine torque input to the axle from the target axle drive torque Tsd in block B42 and divides the result by the reduction gear ratio Gf of final gear 4. Then, the electric motor torque command value Tpm is calculated. The target axle drive torque Tpd corresponds to the target axle drive torque Tsd of the first embodiment, and the electric motor torque command value Tpm corresponds to the electric motor torque command value Tsm of the first embodiment. Another code is used because the map applied in block B15 is different from the map applied in the first embodiment.

  The integrated controller 9 outputs the output torque command value Tpm to the inverter 11, thereby vector-controlling the output torque of the electric motor 3.

  On the other hand, the integrated controller 9 calculates the target drive output of the electric motor 3 in block B43 by multiplying the electric motor torque command value Tpm by the actual electric motor rotation speed calculated from the vehicle speed.

  The integrated controller 9 is block B44, and calculates the energy loss of the electric motor 3 and adds the energy loss to the target drive output to calculate the target power supply to the electric motor 3 as in the block B18 of the first embodiment. .

  Similarly to the first embodiment, the integrated controller 9 calculates the target drive output Ppd of the vehicle in block B17, and then adds the energy loss accompanying the operation of the generator / motor 2 to the target drive output Psd in block B19. Calculate the target engine output Peng. The target drive output Ppd corresponds to the target drive output Psd of the first embodiment.

  The process from the target engine output Peng to the calculation of the engine torque command value Tp and the provisional generator torque command value Tg ′ is the same as in the first embodiment. The engine torque command value Tp corresponds to the engine torque command value Ts of the first embodiment.

  In the first embodiment, the block B18 is provided and the energy loss due to the operation of the electric motor 3 is added to the target drive output Psd.However, in this embodiment, a part of the engine output is directly transmitted without going through the electric motor 3. Since it is input to the final gear 4, the energy loss caused by the operation of the electric motor 3 is not added here, but is added when calculating the target input power of the electric motor 3 in block B44.

  On the other hand, the integrated controller 9 is the block B27, and the surplus is obtained by subtracting the target supply power to the electric motor 3 calculated in the block B44 from the sum of the output possible voltage of the power storage device 6 and the actual generated power of the generator / motor 2. Calculate power Prem.

  The processing of blocks B28-B32 is the same as that in the first embodiment. That is, based on the surplus power Prem, the output possible torque Tgl when the generator / motor 2 is operated as an electric motor and the required power generation torque Tgm when the generator / motor 2 is operated as a generator are calculated, and the temporary generator torque is calculated based on these. Based on the command value Tg ', correct the generator / motor 2 drive torque command value Tg.

  Also in this embodiment, immediately after the accelerator pedal 12 is depressed, all the electric power that can be output from the power storage device 6 is supplied to the electric motor 3 to prevent the supply power to the generator / motor 2 from being insufficient. Preferably, a rapid increase in power consumption of the electric motor 3 is suppressed.

  When accelerating, supplying power to the generator / motor 2 and driving it as a motor accelerates the change in the transmission gear ratio of the planetary gear mechanism 14. However, if the increase speed of the target axle drive torque Tpd calculated in block B15 with respect to the depression of the accelerator pedal 12 is large, there is still a possibility that the increase in the torque of the engine 1 cannot catch up with the change in the gear ratio. For this reason, a limit may be added to the rate of increase of the target axle drive torque Tpd, together with the suppression of the rapid increase in power consumption of the electric motor 3.

  Next, with reference to FIGS. 7-9, the operation and effect of the control according to this embodiment will be described. All of these timing charts show the results of simulations by the inventors of the power characteristics of the parallel hybrid vehicle when the accelerator pedal 12 is fully depressed when ten seconds have elapsed since the vehicle stopped. In both cases, the output power of power storage device 6 is set to 3 kilowatts.

  Fig. 7 shows the acceleration characteristics when the control of Fig. 4 is applied. Fig. 8 shows the acceleration characteristics of the parallel hybrid vehicle of Fig. 2 when the change in the gear ratio of the planetary gear mechanism 14 is set to a high speed without depending on the control of Fig. 4. Fig. 9 shows the acceleration characteristics of the parallel hybrid vehicle of Fig. 2 when the change in the gear ratio of the planetary gear mechanism 14 is set to be slow and power is not supplied to the generator / motor 2.

  Referring to FIG. 8, when the speed change of the planetary gear mechanism 14 is accelerated when the vehicle accelerates from a stopped state, the battery power of the power storage device 6 is supplied to the generator / motor 2 first, and FIG. As shown, engine 1 and generator / motor 2 increase the rotational speed with good response. However, since the power supplied to the electric motor 3 is reduced accordingly, a slight time lag occurs until the output torque of the electric motor 3 starts to increase as shown in FIG. 8 (B). As a result, as shown in FIG. 8 (E), the timing at which the acceleration of the vehicle begins to increase is also delayed. When the generator / motor 2 that has increased the rotational speed starts generating power, the driving force of the vehicle increases as shown in FIG. 8 (C).

  Referring to FIG. 9, when power is not supplied to generator / motor 2, generator / motor 2 increases the rotation speed only depending on the output increase of engine 1, so generator / motor 2 and engine 1 It takes time to increase the rotation speed. As a result, it takes time for the generated power of the generator / motor 2 to satisfy the requirements of the electric motor 3, and favorable acceleration characteristics cannot be obtained.

  Referring to FIG. 7, under the control shown in FIG. 4, the power supplied to the electric motor 3 is first secured with respect to the depression of the accelerator pedal 12, and the surplus power is supplied to the generator / motor 2. The Therefore, as shown in FIG. 7 (B), the output torque of the electric motor 3 increases with good response, while the rotational speeds of the engine 1 and the generator / motor 2 also increase rapidly. As a result, the driving force and acceleration of the vehicle start to rise rapidly without a time lag, and the rotational speed of the generator / motor 2 quickly reaches the speed necessary to satisfy the required generated power. As a result, compared with the characteristics shown in FIG. 8, the arrival timing of the vehicle driving force reaches the peak earlier, the driving force increases in response to depression of the accelerator pedal, and a quick acceleration response is obtained.

  In each of the above embodiments, the block B15 in FIGS. 2 and 4 corresponds to the target drive torque setting means. Block B16 in FIG. 2 and block B42 in FIG. 4 correspond to the second motor power supply means and the second motor target output torque calculation means. Block B28 in Fig. 2 and Fig. 4 corresponds to the first motor supplyable power calculation means. Blocks B17-B19 and B21 in FIG. 2 and blocks B17, B19 and B21 in FIG. 4 correspond to target rotational speed calculation means, respectively. Block B17 further corresponds to vehicle target driving force calculation means. Blocks B28, B30, and B32 in Figs. 2 and 4 correspond to the first motor power supply means. Block B17 in FIGS. 2 and 4 corresponds to vehicle target driving force calculation means. Blocks B29, B31 and B32 in Figs. 2 and 4 correspond to the first motor generated power control means. Blocks B19 and B21-B23 in FIGS. 2 and 4 correspond to provisional power generation calculation means, and blocks B29, B31 and B32 correspond to first power generation control means, respectively. Block B15 in Fig. 2 and Fig. 4 corresponds to the upper limit regulating means. Block B41 in FIG. 4 corresponds to vehicle drive torque calculation means, blocks B42 to B44 correspond to second motor target supply power calculation means, and blocks B29, B31 and B32 correspond to second generated power control means, respectively.

  In each of the above embodiments, the generator / motor 2 and the electric motor 3 are constituted by AC rotating machines controlled via inverters 8 and 10, respectively, but a DC rotating machine can also be used. It is. In that case, the generator / motor 2 and the electric motor 3 are controlled using a DC / DC converter instead of the inverters 8 and 10.

  The present invention is not limited to the above embodiment. It is obvious that various modifications and improvements that can be made by those skilled in the art are included within the scope of the technical idea described in the claims.

1 is a schematic configuration diagram of a control device for a series hybrid electric vehicle according to a first embodiment of the present invention. It is a block diagram explaining the control function of the integrated controller by 1st Example of this invention. FIG. 5 is a schematic configuration diagram of a control device for a parallel hybrid electric vehicle according to a second embodiment of the present invention. It is a block diagram explaining the control function of the integrated controller by 2nd Example of this invention. It is a schematic block diagram of the differential mechanism with which a parallel hybrid electric vehicle is provided. 6 is a diagram for explaining the relationship between the rotational speeds of a generator / motor, an engine, and a drive motor of a parallel hybrid electric vehicle. It is a timing chart explaining the acceleration characteristic which the control by the 2nd example of this invention brings about. It is a timing chart explaining the acceleration characteristic of a parallel hybrid electric vehicle when the target increase rate of the rotational speed of the electric motor is set to be large. 6 is a timing chart for explaining acceleration characteristics of a parallel hybrid electric vehicle when power is not supplied to a generator / motor.

Explanation of symbols

1 engine
2 Generator / Motor
3 Electric motor
6 Power storage device
9 Integrated controller
12 Accelerator pedal
12A accelerator pedal depression amount sensor
13 Vehicle speed sensor
14 Planetary gear mechanism
16 Sungear
17 Ring gear
18 Career

Claims (8)

An accelerator pedal, an engine that consumes fuel and outputs rotational torque to the output shaft, and a first generator that generates electric power according to the rotational torque of the output shaft of the engine and transmits rotational torque to the engine according to supplied power A motor, a second motor that generates a driving torque of the vehicle according to the supplied power, and the first motor and the second motor are electrically connected to supply power to the first motor and the second motor. And a hybrid vehicle comprising a power storage device having a function of storing power generated by the first motor,
Target drive torque setting means for setting the target drive torque of the vehicle according to the depression amount of the accelerator pedal;
Second motor power supply means for supplying power corresponding to the target drive torque from the power storage device to the second motor;
A first motor suppliable power calculating means for subtracting the power supplied to the second motor from the output possible power of the power storage device to calculate the suppliable power to the first motor;
Target rotational speed calculation means for calculating the target rotational speed of the engine based on the target drive torque;
When the electric power that can be supplied to the first motor is a positive value and the target rotational speed of the engine exceeds the rotational speed of the engine, the first electric power is within a range that does not exceed the electric power that can be supplied to the first motor. First motor power supply means for supplying power from the power storage device to the motor;
A driving force control apparatus for a hybrid electric vehicle, comprising:   The second motor power supply means calculates the target output torque of the second motor based on the target drive torque, and controls the operation of the second motor so that power corresponding to the target output torque is consumed. The driving force control apparatus for a hybrid electric vehicle according to claim 1, further comprising:   Vehicle target driving force calculating means for calculating the target driving force of the vehicle from the target driving torque and the vehicle speed, and when the power corresponding to the target driving force exceeds the outputable power of the power storage device, the target driving amount equivalent power and the power storage device The driving power control device for a hybrid electric vehicle according to claim 1, further comprising: first motor generated power control means for controlling generated power of the first motor in accordance with a difference in power that can be output. Temporary generator torque command value calculating means for calculating, as a temporary generator torque command value, a torque required to reduce the difference between the target engine speed of the engine and the rotation speed of the first motor, and first motor generated power control means Is the required power generation torque corresponding to the difference between the target drive amount equivalent power and the output power of the power storage device and the temporary generator torque command value when the power corresponding to the target drive force exceeds the output power of the power storage device. The driving force control device for a hybrid electric vehicle according to claim 3, wherein the power generation power of the first motor is controlled so as to realize the generated torque command value, with the larger of the generated torque command value as the generated torque command value. .   The driving force control device for a hybrid electric vehicle according to any one of claims 1 to 4, further comprising upper limit regulating means for regulating an upper limit of a change rate of the target driving force.   6. The hybrid electric vehicle is constituted by a parallel hybrid electric vehicle in which an engine output shaft, a first motor, and a second motor are mechanically linked via a differential gear mechanism. The drive force control apparatus of the hybrid electric vehicle in any one.   The differential gear mechanism according to claim 6, comprising a planetary gear mechanism comprising a sun gear coupled to the first motor, a ring gear coupled to the second motor, and a carrier coupled to the output shaft of the engine. A driving force control device for a hybrid electric vehicle.   Vehicle drive torque calculation means for calculating the vehicle drive torque of the engine output from the engine via the planetary gear mechanism, and target supply to the second motor based on the torque obtained by subtracting the vehicle drive torque of the engine from the target drive torque A second motor target supply power calculating means for calculating the power, and when the target supply power exceeds the outputable power of the power storage device, the first motor The driving power control device for a hybrid electric vehicle according to claim 7, further comprising second generated power control means for controlling the generated power.

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