JP2011073533A - Control device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control device for a vehicle improving target followability of a power source. <P>SOLUTION: Respective upper and lower limit torques of multiple power generating devices such as an engine 1 and a motor 5 are calculated, and respective torque command values of the multiple power generating devices (the engine 1 and the motor 5, for example) are calculated based on the calculated upper and lower limit torques and the target drive torque. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vehicle control apparatus including a plurality of power sources.

  As a vehicle including a plurality of power sources, for example, a hybrid vehicle including an engine and a motor as drive sources is known. There are several types of hybrid vehicle drive devices such as a drive device equipped with a plurality of motors, a drive device combining an automatic transmission (AT) and a motor, and a drive device combining a continuously variable transmission (CVT) and a motor. There are known drive devices. Many of the above-described drive devices for hybrid vehicles have been developed for the purpose of improving fuel efficiency. For this reason, in a hybrid vehicle equipped with the above-described driving device, it is important how to distribute the driving force of the engine and the driving force of the motor. Power performance can be improved.

  As background art related to the above-described driving force distribution, for example, those disclosed in Patent Documents 1 to 5 are known. Among these, Patent Document 1 discloses a technique for setting a target torque that is set based on a change from the fully open to fully closed accelerator pedal opening, and distributing the target torque to the engine torque and the motor torque. Yes. Patent Document 2 discloses a technique for distributing a target driving torque between a front wheel shaft and a rear wheel shaft according to a determined driving force distribution rate. Patent Document 3 discloses a technique for controlling distribution from target torque to engine torque and motor torque by a feedback constant. Patent Documents 4 and 5 disclose a technique for switching a control method in accordance with a running condition so that the engine torque and the motor torque follow the target drive torque.

Japanese Patent No. 3655263 JP 2002-233006 A JP-A-6-233411 Japanese Patent No. 3216082 Japanese Patent No. 2796698

  In a vehicle equipped with a plurality of power sources, the power distribution of which power of the plurality of power sources is preferentially allocated to the required power based on the operation state of the vehicle and the characteristics of each of the plurality of power sources. The priority changes. For example, in a hybrid vehicle provided with an engine and a motor as a plurality of power sources, the operating point with high fuel consumption efficiency of the engine and the operating point with high efficiency of the motor exist as regions instead of one point. For this reason, in the hybrid vehicle, based on the running state of the vehicle and the state of each component that constitutes the drive system, the power that preferentially distributes the torque of the engine or motor to the required torque. Allocation priority criteria also change.

  At this time, there are cases where the control methods of the plurality of power sources are switched. However, it is considered that the responsiveness of the power source to the operation command value may be reduced due to a change in the value due to switching of the control methods of the plurality of power sources, and the control accuracy may be reduced. For example, in the hybrid vehicle, using a method for preferentially controlling the operating point of the engine, switching from a state in which the engine torque command value is operated by a filter or the like to a method for preferentially controlling the operating point of the motor, When the engine torque command value is changed sharply, it is considered that the response of the engine is delayed by a filter or the like, thereby reducing the accuracy of vehicle drive control. Further, even when switching from a system that preferentially controls the operating point of the motor to a system that preferentially controls the operating point of the engine, it may be necessary to control the response of the engine or motor.

  Further, in the acceleration state of the hybrid vehicle, it is desirable to operate the motor so that the output of the engine is supplemented by the output of the motor. However, the hybrid vehicle is traveling at a constant speed, during deceleration, and during output limitation due to heat generation of the motor. In this state, it is desirable to operate the motor at a point where the motor can generate electric power and has good fuel efficiency. For this reason, in the hybrid vehicle, it is necessary to switch the calculation method of power distribution, and it is considered that the accuracy of drive control of the vehicle may be lowered as described above.

  One of the representative aspects of the present invention provides a vehicle control device capable of improving the target tracking performance of a power source.

  Here, one of the representative aspects of the present invention calculates the upper and lower limit torques of each of the plurality of power generators, and each of the plurality of power generators based on the calculated upper and lower limit torques and the target drive torque. The torque command value is calculated.

  According to one of the representative aspects of the present invention, the target tracking performance of the power source can be improved, so that the control accuracy of the vehicle can be improved.

1 is a block diagram showing the configuration of a hybrid vehicle drive system that is a first embodiment of the present invention. The block diagram which shows the structure of the hybrid control apparatus of FIG. The block diagram which shows the structure of the drive torque distribution calculation block of FIG. The block diagram which shows the structure of the hybrid control apparatus of the hybrid vehicle which is 2nd Example of this invention. The block diagram which shows the structure of the drive torque distribution calculation block of FIG. The time chart which shows the change of a motor upper / lower limit torque when a battery charge amount becomes low. The time chart which shows the change of an engine upper / lower limit torque when a battery electrical storage amount becomes low. The block diagram which shows the structure of the drive system of the hybrid vehicle which is 3rd Example of this invention. The block diagram which shows the structure of the drive torque distribution calculation block of the hybrid control apparatus of FIG. The block diagram which shows the structure of the drive system of the hybrid vehicle which is 4th Example of this invention. The block diagram which shows the example of improvement of the drive torque distribution calculation block of FIG.

  Examples of the present invention will be described below.

  In the embodiments described below, the present invention will be described by taking as an example a case where the present invention is applied to a hybrid vehicle that runs using an engine and a motor.

  The configuration of the embodiment described below includes a hybrid railway vehicle that travels using an engine and a motor, a hybrid construction machine that travels using an engine and a motor, or turns a vehicle body or operates an arm. You may apply to the hybrid apparatus of.

  A first embodiment of the present invention will be described with reference to FIGS.

  First, a drive system for a hybrid vehicle will be described with reference to FIG.

  The hybrid vehicle drive system shown in FIG. 1 is configured to drive a vehicle using either one of the engine 1 provided as the first power generation device or the motor 5 provided as the second power generation device, and to drive the vehicle using both powers. It is possible to use a parallel hybrid system in which the flow of energy transmitted to the wheels from a plurality of power sources is parallel.

  As a drive system, a so-called series-parallel hybrid system in which a parallel hybrid system is combined with a system that drives a generator by dividing a part of engine power may be used.

  The engine 1 is an internal combustion engine that generates power by compressing and burning a mixture of air and fuel (for example, gasoline). The engine 1 is provided with an electronically controlled throttle valve 10. The output of the engine 1 is controlled by controlling the operation of the electronic control throttle valve 10 based on the request signal output from the engine control device 9 and controlling the amount of air supplied to the engine 1.

  As the first power generation device, a motor or another power device may be used.

  The motor 5 is a rotating electric machine that generates power by rotating the armature or the field by the magnetic action of the armature (for example, the stator) and the field (for example, the rotor), and torque is applied in the acceleration direction of the rotating shaft. Since both the power running to generate the power and the power generation (regeneration) to generate the torque in the deceleration direction of the rotating shaft are possible, it is also called a motor generator. In this embodiment, the motor 5 is provided with a permanent magnet for the field and a three-phase winding for the armature, and is synchronized with the rotating magnetic field generated by the supply of the three-phase AC power to the three-phase winding. Permanent magnet field type three-phase AC synchronous machine with rotating magnets is used.

  As the motor 5, an induction motor, a pressure motor combining a pump using pneumatic pressure or hydraulic pressure, and a turbine may be used. The configuration of the present embodiment described below can also be applied to the case where a motor having only a power running action is used as the motor 5.

  The engine shaft (output shaft) of the engine 1 is mechanically connected to the input shaft 21 of the transmission 2 via a clutch 41 capable of intermittent (transmitting and interrupting) rotational energy. A rotor of the motor 5 is provided on the input shaft 21 of the transmission 2. The output shaft 3 of the transmission 2 is mechanically connected to the wheels 4 via a differential gear (not shown).

  The transmission 2 is a power transmission mechanism that amplifies the torque of the input shaft 21 (changes the rotational torque and rotational speed) and transmits the amplified torque to the output shaft 3. In the present embodiment, an automatic transmission that automatically switches the gear position according to the vehicle speed is used as the transmission 2. The transmission 2 includes a transmission mechanism for forming a plurality of shift stages and an actuator for switching the shift stages of the transmission mechanism. The switching of the gear position is controlled by controlling the operation of the actuator based on the request signal output from the transmission control device 11 and switching the gear position of the transmission mechanism.

  The transmission 2 may be a manual transmission that manually switches the shift speed, a continuously variable transmission that does not have a shift speed, or the like.

  An inverter device 7 as a motor control device is electrically connected to the three-phase winding of the armature of the motor 5. A battery 6 that is a driving power source for the motor 5 is electrically connected to the inverter device 7. The inverter device 7 converts the DC power supplied from the battery 6 into three-phase AC power during powering of the motor 5 and supplies it to the three-phase winding of the armature of the motor 5 to control the driving of the motor 5. -AC power conversion device, and at the time of power generation (regeneration) of the motor 5, a three-phase AC power generated by the motor 5 is converted to DC power and supplied to the battery 6 to charge the battery 6 (AC- A power conversion device capable of DC power conversion). The battery 6 is a power storage device having a rated output of 200 volts or more, including a battery pack in which a plurality of chargeable / dischargeable lithium ion batteries or a plurality of nickel metal hydride batteries are electrically connected in series.

  The inverter device 7 includes a power conversion circuit that performs power conversion by switching (on and off) a plurality of switching semiconductor elements, a control circuit that outputs a switching command signal for controlling the operations of the plurality of switching semiconductor elements, and a control A drive circuit is provided for supplying the switching command signal output from the circuit to the gates of the plurality of switching semiconductor elements as a drive signal of a voltage necessary for driving the plurality of switching semiconductor elements.

  The battery 6 includes a cell control circuit for detecting the voltage of each battery, adjusting the state of charge of each battery, detecting overcharge / discharge of each battery, detecting the voltage of the assembled battery, detecting the current of the assembled battery, and detecting the temperature of the battery. In addition, a battery control circuit is provided for performing detection of charging and discharging states of the assembled battery, calculation of allowable charging / discharging power (current) for controlling charging / discharging of the assembled battery, and the like.

  The operation of the drive system of the hybrid vehicle is controlled by the hybrid controller 8. The hybrid control device 8 includes an engine control device 9, a transmission control device 11, a control circuit for the inverter device 7, a battery control circuit for the battery 6, a rotation sensor 31 for detecting the rotation speed or torque of the input shaft 21, and Relating to information necessary for hybrid drive control, such as a signal output from the rotation sensor 33 for detecting the rotation speed or torque of the output shaft 3 and an accelerator pedal opening (or electronic throttle valve 10 opening) signal A signal is being input.

  The hybrid control device 8 calculates the target drive torque of the vehicle, the upper limit value and the lower limit value of the engine torque, and the upper limit value and the lower limit value of the motor torque based on the information obtained from these input signals, and the target value. An engine torque command value and a motor torque command value for outputting drive torque are calculated, and signals corresponding to the engine torque command value and the motor torque command value are output. Further, the hybrid control device 8 outputs a signal corresponding to a clutch command for opening and closing the clutch 41 and a signal corresponding to a shift command for switching the gear position of the transmission 2.

  A signal corresponding to the engine torque command value is input to the engine control device 9. Thereby, the opening degree (air amount) of the electronic control throttle valve 10 is controlled, and the torque output from the engine 1 is controlled. A signal corresponding to the motor torque command value is input to the control circuit of the inverter device 7. Thereby, the switching operation (three-phase AC power supplied to the motor 5) of the plurality of switching semiconductor elements of the inverter device 7 is controlled, and the torque output from the motor 5 is controlled. A signal corresponding to the clutch command is input to a drive circuit of a clutch 41 (for example, an electromagnetic clutch). Thereby, the excitation current (electromagnetic force) supplied to the excitation winding is controlled, and the engagement state of the clutch 41 is controlled. A signal corresponding to the shift command is input to the transmission control device 11. As a result, the shift speed change (gear ratio) of the speed change mechanism of the transmission 2 is controlled, and the output (product of torque and rotation speed) transmitted from the input shaft 21 to the output shaft 3 is controlled.

  The functions of the hybrid control device 8 may be integrated into any one of the engine control device 9, the transmission control device 11, and the control circuit of the inverter device.

  Next, the configuration (function) of the hybrid control device 8 will be specifically described with reference to FIG.

  In FIG. 2, calculation blocks corresponding to the calculation functions of the engine torque command value and the motor torque command value are shown, and calculation blocks corresponding to other functions are omitted.

  The hybrid control device 8 includes a target drive torque calculation unit 81, an engine upper / lower limit torque calculation unit 82, a motor upper / lower limit torque calculation unit 83, and a drive torque distribution calculation unit 84, and calculates an engine torque command value and a motor torque command value. , The corresponding signals are output.

  The target drive torque calculation unit 81 includes an accelerator opening indicating an accelerator pedal depression amount, which is the driver's intention of acceleration / deceleration, an accelerator opening speed that is a change value of the accelerator depression amount, a vehicle speed, and an engine rotation speed. Information is acquired from an input signal, and a target drive torque value (tTout) is calculated and output based on the information.

  The memory of the hybrid control device 8 stores in advance a data table (map) indicating the relationship between the accelerator opening, the accelerator opening speed, the vehicle speed, the engine speed, and the target drive torque value. The value is calculated from the stored data table with reference to input information of accelerator opening, accelerator opening speed, vehicle speed, and engine speed.

The engine upper / lower limit torque calculation unit 82 acquires information on the engine rotation speed from the input signal, and calculates and outputs the upper limit torque (Teng _H ) and the lower limit torque (Teng _L ) of the engine 1 based on the information. As the upper limit torque (Teng _H ) and the lower limit torque (Teng _L ) of the engine 1, it is desirable to calculate an operating point torque with high efficiency of the engine 1. For example, when there is one engine torque point with the highest efficiency at a certain engine rotation speed, the upper limit torque of the engine 1 is set to a threshold value that is higher than a certain efficiency on the higher torque side than the point with the highest efficiency. Further, the lower limit torque of the engine 1 is set to a threshold value that is equal to or higher than a certain efficiency on the lower torque side than the most efficient point. By setting in this way, if the apparatus of the present invention is used, it becomes possible to operate the engine at an operating point of a certain efficiency or more, which can contribute to an improvement in fuel consumption. Furthermore, since the lower limit torque of the engine 1 plays an important role in the present invention, it is possible to increase the fuel efficiency improvement rate by adjusting the lower limit torque of the engine 1 at a point with the highest efficiency, for example.

  Still further, for example, when it is desired to run only by the motor, the upper limit torque and the lower limit torque of the engine 1 are set to the same value and the value is set to 0, so that only the motor can be run by the distribution calculation device described later. It becomes.

The motor upper / lower limit torque calculation unit 83 acquires information on the amount of charge (SOC indicating the state of charge) of the battery 6 from the input signal, and based on the information, the upper limit torque (Tmot _H ) and the lower limit torque (Tmot _L ) of the motor 5. ) Is calculated and output. Here, the upper limit torque and the lower limit torque of the motor 5 are the upper limit value and the lower limit value, respectively, so that the motor torque at a certain number of rotations of the motor 5 falls within a high motor efficiency range in the same manner as the upper limit torque and the lower limit torque of the engine 1. By setting, it is possible to improve fuel efficiency. Further, when the limit of charge / discharge is small due to the temperature of the motor or the storage level of the battery, setting the limit value helps to protect the motor. At this time, the engine torque is increased by a distribution calculation described later, and as a result, the vehicle can travel without impairing the driving force of the vehicle.

The drive torque distribution calculation unit 84 generates an engine torque command value (rTeng) based on the target drive torque (tTout), the engine upper / lower limit torque (Teng _H ) (Teng _L ), and the motor upper / lower limit torque (Tmot _H ) (Tmot _L ). And the motor torque command value (rTmot) is calculated.

  Next, the configuration (calculation method) of the drive torque distribution calculation unit 84 will be specifically described with reference to FIG.

  First, the target drive torque (tTout) indicates the torque in the output shaft 3. For this reason, when calculating the engine torque command value and the motor torque command value, it is necessary to convert the upper and lower limit torques to the torque in the output shaft 3 in accordance with the target drive torque (tTout). For this reason, each upper and lower limit torque is multiplied by the current gear ratio in the output shaft converter 84a and converted into torque in the output shaft 3. Hereinafter, each upper and lower limit torque will be described as a value converted into torque in the output shaft 3.

Next, calculation of the motor torque command value (rTmot) will be described. In the subtractor 84b, a difference between the target drive torque (tTout) and the engine lower limit torque (Teng _L ) is obtained. This difference is a torque amount that compensates for the shortage of the target drive torque (tTout) by the motor 5 with reference to the engine lower limit torque (Teng _L ). However, since the output of the motor 5 may be limited due to temperature or the like, the difference between the target drive torque (tTout) and the engine lower limit torque (Teng _L ) is determined by the motor upper and lower limit torque (Tmot _H ) (Tmot _L ). The motor torque command value (rTmot) is set as the motor torque command value. For this reason, first, the minimum value selector 84c selects the minimum value by comparing the difference between the target drive torque (tTout) and the engine lower limit torque (Teng _L ) with the motor upper limit torque (Tmot _H ). The maximum value selector 84d compares the minimum value selected by the minimum value selector 84c with the motor lower limit torque (Tmot _L ) and selects the maximum value. Finally, the motor shaft converter 84f The maximum value selected by the value selector 84d is multiplied by the reciprocal of the current gear ratio. Thereby, a motor torque command value (rTmot) can be calculated.

Next, calculation of the engine torque command value (rTeng) will be described. If the motor torque command value (rTmot) is determined, the engine torque command value (rTeng) is obtained from the difference between the target drive torque (tTout) and the motor torque command value (rTmot). Therefore, the subtractor 84a obtains the motor torque command value (rTmot) before being converted by the motor shaft converter 84, that is, the difference between the output of the maximum value selector 84d and the target drive torque (tTout). However, when the operating range of the motor 5 is very small, the engine torque becomes too large, so the difference between the motor torque command value (rTmot) and the target drive torque (tTout) is limited by the engine upper limit torque (Teng _H ). This limited value is used as the engine torque command value (rTeng). Therefore, the minimum value selector 84c selects the minimum value by comparing the difference between the motor torque command value (rTmot) and the target drive torque (tTout) with the engine upper limit torque (Teng _H ), and finally the engine. The shaft converter 84e multiplies the minimum value selected by the minimum value selector 84c by the reciprocal of the current gear ratio. Thereby, the engine torque command value (rTeng) can be calculated.

  Usually, each upper and lower limit torque has a certain range. For this reason, the upper and lower limit torques of the engine 1 are both positive values, and the relationship of upper limit value> lower limit value is established. Also. The upper and lower limit torques of the motor 5 are set such that the upper limit value is a positive value and the lower limit value is a negative value. In this way, the motor 5 can select positive and negative values, and can command a value that compensates for excess or deficiency of the target drive torque and engine torque.

  Here, the positive and negative torque values of the motor 5 are assumed when the vehicle is moving forward. Normally, forward and reverse are switched only in the rotational speed from the transmission 2 to the axle. For this reason, if the rotational speed is determined to be the same direction, the positive torque of the motor 5 is a torque during power running and acts in the acceleration direction of the vehicle. Further, the negative torque is a torque at the time of power generation (regeneration), and acts in the deceleration direction of the vehicle.

  According to the present embodiment described above, the upper and lower limit torques are calculated for each of the engine 1 and the motor 5, and the calculated upper and lower limit torques and the target drive torque are selectively selected according to a predetermined calculation logic. Since the torque command value for each of the engine 1 and the motor 5 is calculated, the followability of the operation of the engine 1 and the motor 5 with respect to the torque command value can be improved, and the accuracy of vehicle drive control can be improved. it can.

  A second embodiment of the present invention will be described with reference to FIGS.

  This embodiment is an improved example of the first embodiment, and differs from the first embodiment in the configuration of the hybrid control device 8 and the calculation logic of the engine torque command value and the motor torque command value. The configuration of the hybrid vehicle drive system is the same as that of the first embodiment.

In the drive torque distribution method shown in FIG. 3, first, a motor torque command value is calculated based on the difference between the target drive torque (tTout) and the engine lower limit torque (Teng _L ). However, when the engine lower limit torque (Teng _L ) changes, a deviation may occur between the target value of the engine torque and the current value. At this time, there is no particular problem when the engine torque is gradually changed. However, when the engine torque is suddenly changed, a deviation occurs between the sum of the engine torque and the motor torque and the target drive torque. When the rotational speed of the engine 1 is low, a response delay of intake air occurs, resulting in poor torque response. On the other hand, the motor has high responsiveness. For this reason, when the timings of both commands are the same, the followability to the target drive torque is lowered due to the difference in response. In order to avoid such a problem, it is possible to cope with the problem by calculating the motor torque using the current engine torque instead of using the engine command torque having low response to the target drive torque.

  Therefore, in this embodiment, as shown in FIG. 4, an engine torque calculation unit 85 is provided to estimate and calculate the current engine torque (Tenge) based on the engine state such as the engine speed and the intake air amount. The estimated engine torque (Tenge) is used as a calculation parameter in the drive torque distribution calculation unit 84.

  The current engine torque (Tenge) may be detected from an output signal of the torque sensor provided in the engine 1.

  In the drive torque distribution method shown in FIG. 3, since the motor torque command value is calculated and the rest is used as the engine torque command value, the engine torque command value becomes the same value as the current engine torque. For this reason, it is necessary to determine the engine torque command value with respect to the engine upper and lower limit torque. Further, the engine torque command value must be an engine torque within a range where the motor torque can be output within the range of the engine upper and lower limit torque. For this reason, the engine torque command value must first be subtracted from the target drive torque again, with the value obtained by subtracting the engine lower limit torque from the target drive torque, and a value provided with a limit on the motor upper and lower limit torque.

  Therefore, in this embodiment, the engine torque command value and the motor torque command value are calculated as shown in FIG.

  First, similarly to the first embodiment, in the output shaft converter 84a, the upper and lower limit torques and the current engine torque are multiplied by the current gear ratio, and the upper and lower limit torques and the current engine torque are respectively converted to torques on the output shaft 3. Convert. Hereinafter, each upper and lower limit torque and the current engine torque will be described as values converted into torque in the output shaft 3.

Next, calculation of the motor torque command value (rTmot) will be described. In the subtractor 84b, the difference between the target drive torque (tTout) and the current engine torque (Tenge) is obtained. This difference is a torque amount that compensates for the shortage of the target drive torque (tTout) by the motor 5 with reference to the engine lower limit torque (Teng _L ). However, since the output of the motor 5 may be limited due to temperature or the like, the difference between the target drive torque (tTout) and the current engine torque (Tenge) is limited by the motor upper / lower limit torque (Tmot _H ) (Tmot _L ). The limited value is set as a motor torque command value (rTmot). Therefore, first, in the minimum value selector 84c, the difference between the target drive torque (tTout) and the current engine torque (Tenge) is compared with the motor upper limit torque (Tmot _H ) to select the minimum value, and then The maximum value selector 84d selects the maximum value by comparing the minimum value selected by the minimum value selector 84c with the motor lower limit torque (Tmot _L ). Finally, the maximum value is selected by the motor shaft converter 84f. The maximum value selected by the selector 84d is multiplied by the reciprocal of the current gear ratio. Thereby, a motor torque command value (rTmot) can be calculated.

Next, calculation of the engine torque command value (rTeng) will be described. In calculating the engine torque command value (rTeng), the engine lower limit torque (Teng _L ) is subtracted from the target drive torque (tTout) to limit the motor torque, and then the value is subtracted from the target drive torque (tTout) again. There is a need. Therefore, first, the subtracter 84b obtains the difference between the target drive torque (tTout) and the engine lower limit torque (Teng _L ), and then the minimum value selector 84c uses the target drive torque (tTout) and the engine lower limit torque. The minimum value is selected by comparing the difference with (Teng _L ) and the motor upper limit torque (Tmot _H ). Next, in the maximum value selector 84d, the minimum value selected by the minimum value selector 84c and the motor The maximum value is selected by comparing with the lower limit torque (Tmot _L ), and then, in the subtractor 84b, the maximum value selected in the maximum value selector 84d is subtracted from the target drive torque (tTout) again. In the minimum value selector 84c, the difference between the maximum value selected in the maximum value selector 84d and the target drive torque (tTout), the difference between the target drive torque (tTout) and the engine lower limit torque (Teng _L ), The engine upper limit torque (Teng _H ) is compared to select the minimum value, and finally, the engine shaft converter 84e multiplies the minimum value selected by the minimum value selector 84c by the reciprocal of the current gear ratio. Thereby, the engine torque command value (rTeng) can be calculated.

Here, for example, when the storage rate (SOC) of the battery 6 that stores energy for driving the motor 5 becomes low, the motor 5 must normally generate power, and the output of the motor 5 is given priority. Must switch to power generation control. In the present embodiment, by setting the motor upper limit torque (Tmot _H ) to a negative value, the motor 5 automatically generates power, and the motor upper limit torque (Tmot _H ) can be secured at least. Depending on the running state and the state of the engine 1, the power generation torque of the motor 5 may be further required, but by setting the motor lower limit torque (Tmot _L ) to a lower value, further power generation is possible depending on the situation. . Therefore, according to the present embodiment, for example, even when it is necessary to switch to power generation during acceleration assist, it is possible to generate power without switching control.

  FIG. 11 shows an example for realizing the above-described control.

  In the example of FIG. 11, the control shown in FIG. 4 is improved, and a traveling state determination unit 86 is provided for the hybrid control device 8 shown in FIG. The traveling state determination unit 86 is a traveling state command value for performing the “power generation”, “motor traveling”, and “other” states based on the storage amount (charge state) of the battery 6 and the target drive torque (tTout). And the calculated running state command value is output to each of the engine upper / lower limit torque calculation unit 82 and the motor upper / lower limit torque calculation unit 83. Then, the engine upper / lower limit torque calculation unit 82 calculates the engine upper / lower limit torque based on the running state command value output from the running state determination unit 86 and the rotational speed of the engine 1. Further, the motor upper / lower limit torque calculation unit 83 calculates the motor upper / lower limit torque based on the running state command value output from the running state determination unit 86 and the charged amount (charged state) of the battery 6. The torque upper and lower limit values of the engine 1 are calculated according to the accelerator opening in cases other than “power generation” and “motor running”, for example, and are calculated according to the rotational speed of the engine 1 in the case of “power generation”. By calculating in this way, the engine 1 can be operated at an efficient operating point, which will be described later, and the distribution calculation method is not switched, so that the switching of the state within the range of the torque upper and lower limit values of the motor 5 is avoided. Therefore, responsiveness is good and smooth control can be performed.

  Next, the operation when using the power distribution control of this embodiment will be described with reference to FIG.

FIG. 6 shows an engine torque command value (rTeng), a motor torque command value (rTmot), an engine upper limit torque (Teng _H ), an engine lower limit torque (Teng _L ), and a motor upper limit torque (Tmot) with respect to changes in the target drive torque (tTout). _H ), the motor lower limit torque (Tmot _L ), and the state of charge (SOC) of the battery 6 over time.

As shown in FIG. 6, when the target drive torque (tTout) increases for acceleration in the section A, the motor torque command value (rTmot) indicated by the dotted line increases and the energy of the battery 6 is used by the motor 5. As a result, the state of charge (SOC) of the battery 6 decreases. Therefore, if the motor upper limit torque (Tmot _H ) is reduced to a negative value, the motor torque command value (rTmot) can only be output with a negative value, so that the motor 5 is in a power generation state, whereby the battery 6 is charged. (SOC) increases. Along with this, the engine torque command value (rTeng) indicated by the alternate long and short dash line also increases.

Here, the engine lower limit torque (Teng _L ) is usually set to be close to the target drive torque (tTout) based on the engine torque characteristic calculated from the engine speed and the accelerator opening, thereby sharing the torque of the motor 5. Since the ratio decreases and the load on the motor 5 can be reduced, the motor 5 can run stably for a long time without thermal runaway. However, the efficiency of the engine 1 is low when the torque is low, and the engine torque is small when the target drive torque (tTout) is small. For this reason, when operating as described above, an inefficient operating point of the engine 1 is used.

Therefore, when the state of charge (SOC) of the battery 6 is low, the motor 5 generates electric power, and if the torque for the generated electric power is added to the engine torque, the engine torque can be increased despite the small target driving force. It is. However, in order to actively use an operating point with high engine efficiency even after shifting to the power generation state, the motor torque is limited to the motor upper limit torque (Tmot _H ) as shown in FIG. ) And the engine torque cannot be further increased.

Therefore, as shown in FIG. 7, the engine lower limit torque (Teng _L ) is forcibly increased. In this way, the power generation torque of the motor 5 can be increased, and the engine torque can be shifted to an operating point with high engine efficiency, so that traveling with good fuel efficiency can be provided.

Normally, the engine lower limit torque (Teng _L ) is calculated based on the rotational speed and accelerator opening of the engine 1 in the engine upper and lower limit calculation unit 82. When the state of charge (SOC) of the battery 6 is low, the engine 1 By calculating the engine torque (rotational speed lower limit torque) with high combustion efficiency based on the rotational speed and the vehicle speed, the above-described control becomes possible.

7, as in FIG. 6, the engine torque command value (rTeng), the motor torque command value (rTmot), the engine upper limit torque (Teng _H ), and the engine lower limit torque (Teng) with respect to changes in the target drive torque (tTout). _L ), the motor upper limit torque (Tmot _H ), the motor lower limit torque (Tmot _L ), and the state of charge (SOC) of the battery 6 over time.

  A third embodiment of the present invention will be described with reference to FIGS.

The present invention is a modification of the second embodiment, in which the positions of the transmission 2 and the motor 5 are interchanged, and the rotor of the motor 5 is provided on the output shaft 3 of the transmission 2. The structure of the other drive system is exactly the same as in the second embodiment. In the calculation logic of the engine torque command value and the motor torque command value, in the second embodiment, the motor upper limit torque (Tmot _H ) and the motor lower limit torque (Tmot _L ) are converted into output shafts. Since the motor 5 is disposed on the output shaft 3 side of the transmission 2, the motor upper limit torque (Tmot _H ) and the motor lower limit torque (Tmot _L ) need not be converted into output shafts. The other calculation logics of the engine torque command value and the motor torque command value are exactly the same as in the second embodiment.

  Thus, the calculation logic of the engine torque command value and the motor torque command value in the second embodiment hardly changes even when the mounting position of the motor 5 changes. Therefore, the calculation logic of the engine torque command value and the motor torque command value in the present embodiment can be easily developed in a drive system having a different configuration from the present embodiment.

  A fourth embodiment of the present invention will be described with reference to FIG.

  This embodiment is a modification of the second embodiment and is a case where a motor 5 is mounted inside the transmission 2.

  The transmission 2 employs a twin clutch system, as shown in FIG. For this reason, two intermediate shafts 220 and 230 are mechanically connected between the input shaft 21 and the output shaft 3. The motor 5 is mechanically connected to each of the intermediate shafts 220 and 230 via a planetary gear mechanism 190.

  The input shaft 21 can be connected to the intermediate shaft 220 via gears 181, 183, and clutch 171, and can be connected to the intermediate shaft 230 via gears 181, 184, and clutch 172. The input shaft 21 can be connected to the intermediate shaft 230 via a gear 182, a gear 160 for reversing the rotation direction, a gear 185, and a clutch 172.

  The intermediate shaft 220 can be connected to the output shaft 3 via the clutch 176, the gear 140 or the gear 141, the gear 153, or the gear 155. The intermediate shaft 230 can be connected to the output shaft 3 via the clutch 174, the gear 144 or the gear 145, the gear 151 or the gear 150, and the output shaft 3 via the clutch 175, the gear 142 or the gear 143, the gear 154 or the gear 152. Can be connected to.

  Clutch 171 is driven by shift actuator 100, clutch 172 is driven by shift actuator 101, clutch 173 is driven by shift actuator 102, clutch 174 is driven by shift actuator 103, clutch 175 is driven by shift actuator 104, The clutch 176 is engaged and disengaged by the thrust of the shift actuator 105, and transmits and interrupts power.

  The motor 5 is mechanically connected to the shaft of the carrier 190d. The shaft of the ring gear 190b is mechanically connected to the intermediate shaft 230 via a gear and a gear 186 provided on the shaft of the ring gear 190b. The shaft of the sun gear 190a is mechanically connected to the intermediate shaft 220 via a gear and a gear 187 provided on the shaft of the sun gear 190a.

  In such a configuration, the connection gear ratio of the motor 5 changes. However, the output shaft conversion shown in FIG. 3 or FIG. 5 is performed by converting the engine upper / lower limit torque and the current engine torque conversion gear ratio to the motor upper / lower limit torque. The calculation method of the engine torque command value and the motor torque command value shown in FIG. 3 or FIG. 5 can be applied to this embodiment by setting the conversion gear ratio and performing the calculation.

[Modification]
In the first to fourth embodiments, the case where the engine 1 and the motor 5 are mounted as a plurality of power sources has been described as an example. Here, for example, consider a case where two motors are mounted as a plurality of power sources in FIG. Even in such a configuration, since the physiques and characteristics of the two motors may be different from each other, it is necessary to control the distribution of the driving force so that the operating point of the efficiency of one motor is high. In this case, the engine upper and lower limit torques described in the first to fourth embodiments are set as the upper and lower limit torques of one motor, and the motor upper and lower limit torques are set as the upper and lower limit torques of the other motor. As in the first embodiment, the engine torque command value and the motor torque command value can be calculated.

  Consider the case where an engine and a hydraulic pump or hydraulic motor are mounted as a plurality of power sources. In this case, the inverter device is replaced with a hydraulic pump or hydraulic motor control device, and the battery is replaced with a hydraulic tank. However, in the first to fourth embodiments, since the upper and lower limits of the torque are set as basic components, for example, the first drive source is an engine and the second drive source is a hydraulic pump or a hydraulic motor. Even when configured as shown in FIG. 8, the engine torque command value and the hydraulic pump or hydraulic motor torque command value can be calculated as in the first to fourth embodiments.

Claims (6)

Target drive torque calculating means for calculating the target drive torque;
First upper and lower limit torque calculating means for calculating upper and lower limit torques of the first power generation device;
Second upper / lower limit torque calculating means for calculating upper / lower limit torque of the second power generation device;
Drive torque distribution calculating means for calculating a torque command value of the first power generation device and a torque command value of the second power generation device with respect to the target drive torque;
The drive torque distribution calculating means is configured to determine a torque command value of the first power generator and the first and second torques based on the target drive torque, the upper and lower limit torques of the first power generator and the upper and lower limit torques of the second power generator. Calculate the torque command value of the power generator,
A control apparatus for a vehicle. The vehicle control device according to claim 1,
The drive torque distribution calculating means includes
A value selected by the first selector and the first selector for selecting a smaller value of the difference between the target drive torque and the lower limit torque of the first power generator or the upper limit torque of the second power generator. Or a second selector that selects a larger value of the lower limit torque of the second power generator, and sets the value selected by the second selector as a torque command value of the second power generator. ,
A difference between the target drive torque and a torque command value of the second power generation device is set as a torque command value of the first power generation device;
A control apparatus for a vehicle. The vehicle control device according to claim 1,
And first torque calculating means for detecting or estimating the torque of the first power generation device,
The drive torque distribution calculating means includes
The first selector that selects a smaller value of the difference between the torque detected or estimated by the torque calculation means and the target drive torque or the upper limit torque of the second power generator, and is selected by the first selector. A second selector that selects a larger value of the second power generator and the lower limit torque of the second power generator, and sets the value selected by the second selector as the torque command value of the second power generator As well as
A value selected by the third selector and the third selector for selecting a smaller value of the difference between the target drive torque and the lower limit torque of the first power generator or the upper limit torque of the second power generator. Or a fourth selector that selects a larger value of the lower limit torque of the second power generation device, the difference between the value selected by the fourth selector and the target drive torque, or the upper limit torque of the first power generation device A fifth selector that selects a smaller value of the first selector, and sets the value selected by the fifth selector as a torque command value of the first power generation device.
A control apparatus for a vehicle. In the vehicle control device according to any one of claims 1 to 3,
Furthermore, energy is supplied to the second power generation device, and energy supply to the energy storage device is required according to the energy storage state of the energy storage device that receives energy supply from the second power generation device Determining means for determining whether or not
Second torque calculating means for calculating zero or negative torque with respect to the second power generation device according to the energy storage state of the energy storage device;
When the determination unit determines that energy supply to the energy storage device is necessary, the upper limit torque of the second power generation device is set to the torque calculated by the second torque calculation unit.
A control apparatus for a vehicle. In the vehicle control device according to any one of claims 1 to 3,
Furthermore, energy is supplied to the second power generation device, and energy supply to the energy storage device is required according to the energy storage state of the energy storage device that receives energy supply from the second power generation device Determination means for determining whether or not
The first upper / lower limit torque calculating means includes:
Accelerator lower limit torque defined by the vehicle speed or the rotational speed of the first power generator and the accelerator opening, and the rotational speed lower limit torque defined only by the vehicle speed or the rotational speed of the first power generator regardless of the accelerator opening. And calculating
When the determination means determines that energy supply to the energy storage device is not required, the lower limit torque of the first power generation device is the accelerator lower limit torque,
When the determination means determines that energy supply to the energy storage device is necessary, the lower limit torque of the first power generation device is set as the rotation speed lower limit torque.
A control apparatus for a vehicle. The vehicle control device according to claim 4,
The first upper / lower limit torque calculating means includes:
Accelerator lower limit torque defined by the vehicle speed or the rotational speed of the first power generator and the accelerator opening, and the rotational speed lower limit torque defined only by the vehicle speed or the rotational speed of the first power generator regardless of the accelerator opening. And calculating
When the determination means determines that energy supply to the energy storage device is not required, the lower limit torque of the first power generation device is the accelerator lower limit torque,
When the determination means determines that energy supply to the energy storage device is necessary, the lower limit torque of the first power generation device is set as the rotation speed lower limit torque.
A control apparatus for a vehicle.

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