JP2007022118A - Control unit of hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve fuel consumption in a hybrid vehicle by minimizing electric power stored in an electricity storage device while realizing an acceleration request of a driver. <P>SOLUTION: A control unit of a hybrid vehicle estimates limit drive force being conveyable to a road surface by the vehicle on the basis of a road surface condition during running of the vehicle (S40), and calculates margin driving power as power supplied from the electricity storage device to a drive motor (S50), which is power for compensating lacked generating power, when the requested drive force required for the vehicle is increased. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a control device for a hybrid vehicle.

  2. Description of the Related Art A hybrid vehicle that includes an engine and a motor and travels by driving the motor with power generated by a generator using the engine as a driving force source is known. In such a hybrid vehicle, a desired motor driving force is generated by controlling the engine output according to a change in the driver's required driving force.

  However, since the engine has a response delay with respect to the output command, even if the engine output is increased with respect to an increase in the driver's required driving force, the generator power generation is delayed and the response to the vehicle driving force is delayed. May cause driver discomfort.

Therefore, by securing electric power in the power storage device in advance and driving the motor using the power of the power storage device until the engine output rises when the driver's required driving force increases, the driving power of the vehicle is reduced. Japanese Patent Application Laid-Open No. 2004-133867 describes a technique for starting up instantaneously.
JP 2002-271909 A

  Here, in the hybrid vehicle, there are an EV traveling mode in which only the driving force of the motor is traveled, an assist traveling mode in which the engine is operated at a highly efficient operating point during high load traveling, and the insufficient driving force is supplemented by the motor. Fuel consumption can be improved by switching control according to the driving conditions of the vehicle.

  Therefore, if the electric power for driving the motor is always secured in preparation for the driver's acceleration request as in the above-described conventional technology, the electric power that can be supplied from the power storage device is reduced, so that the EV traveling mode and the assist traveling mode are reduced. The opportunity to perform is reduced, and the fuel efficiency improvement effect cannot be obtained accordingly.

  The present invention has been made paying attention to such conventional problems, and aims to improve fuel efficiency by minimizing the amount of electric power secured in the power storage device while realizing the acceleration request by the driver. It is said.

  In the first aspect of the present invention, in a hybrid vehicle control device having a drive motor, a power storage device, and a power generation device, a required drive power calculation means for calculating a required drive power that achieves the required drive force required for the vehicle. And an outputable power calculating means for calculating outputable power that is outputable power of the power storage device, and an upper limit value of driving force that the vehicle can transmit to the road surface based on a road surface state while the vehicle is traveling A limit driving force estimating means for power supply, and a power for supplementing the generated power that is insufficient until the output power of the power generator increases to the target generated power when the required driving power required for the vehicle increases, Based on the upper limit value of the driving force calculated by the marginal driving force estimation unit and the marginal driving power calculation unit that calculates the marginal driving power that is the power supplied to the driving motor from And a target generated power calculating means for calculating the target generated power of the power generator based on the margin drive power, the output possible power, and the required drive power, and the generator of the power generator so that the generated power of the generator becomes the target generated power Generated power control means for controlling the generated power.

  According to the second aspect, in a hybrid vehicle control device having an engine, a drive motor, and a power storage device, required drive power calculation means for calculating a required drive power for realizing the required drive force required for the vehicle, Output power calculation means for calculating output power that is output power of the device, and limit driving for estimating an upper limit value of driving force that the vehicle can transmit to the road surface based on a road surface condition while the vehicle is traveling When the required driving force required for the force estimation means and the vehicle increases, the power is to supplement the generated power that is insufficient until the output power of the power generator increases to the target power. The margin driving power calculation means for calculating the margin driving power that is the power supplied to the power supply, and the margin driving power is calculated based on the upper limit value of the driving force calculated by the limit driving force estimation means. In addition, target engine power calculation means for calculating the target engine power of the engine based on the surplus driving power, the output power and the required driving power, and the engine work so that the engine power becomes the target engine power. Engine power control means for controlling the rate.

  According to the first aspect of the present invention, the marginal drive power supplied from the power storage device to the drive motor in order to compensate for the generated power that is insufficient when the driver requests acceleration, the limit at which the drive power of the drive motor can be transmitted to the road surface. The calculation can be performed while being limited to a range not exceeding the driving force. As a result, it is possible to minimize the amount of electric power reserved in the power storage device for the acceleration request, and to increase the amount of discharge from the power storage device accordingly, thereby reducing the generated power of the power generation device Can do. Therefore, fuel consumption can be improved by reducing the amount of fuel consumed while satisfying the driver's acceleration request.

  Further, according to the second aspect, the marginal driving force that allows the driving force of the driving motor to be transmitted to the road surface is the surplus driving power that is supplied from the power storage device to the driving motor to compensate for the generated power that is insufficient when the driver requests acceleration. The calculation can be performed with the range not exceeding. As a result, the amount of electric power reserved in the power storage device for the acceleration request can be minimized, and the amount of discharge from the power storage device can be increased accordingly. The engine work rate can be reduced. Therefore, fuel consumption can be improved by reducing the amount of fuel consumed while satisfying the driver's acceleration request.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, in each drawing, the same code | symbol was attached | subjected to what performs the same thing and the same process.

(First embodiment)
FIG. 1 is an overall configuration diagram showing a control apparatus for a hybrid vehicle in the present embodiment. The hybrid vehicle of the present embodiment is a series hybrid vehicle, and the generator 1 is directly connected to the engine 2 and rotates by the driving force of the engine 2 to generate electric power, and performs cranking when the engine 2 is started. The power storage device 3 stores power generated by the generator 1 and supplies power to the drive motor 4 and the auxiliary device 5. The power storage device 3 may use any of a lithium ion battery, a nickel metal hydride battery, a capacitor, and the like. The drive motor 4 is driven by at least one of the power generated by the generator 1 and the power stored in the power storage device 3, and the driving force is transmitted to the drive wheels 7 via the final gear 6.

  The engine controller 8 controls the throttle opening of the engine 2 based on the engine torque command value output from the integrated controller 9. The generator controller 10 controls the rotation speed based on the rotation speed command value output from the integrated controller 9. At this time, the generator 1 performs vector control so that the rotational speed of the engine 2 is also equal to the rotational speed command value of the generator 1. The power storage device controller 11 detects the voltage and current of the power storage device 3, calculates the input / output possible power of the power storage device 3, and transmits it to the integrated controller 9. The drive motor controller 12 performs vector control of the torque of the drive motor 4 based on the motor torque command value output from the integrated controller 9.

  The integrated controller 9 includes the voltage / current of the power storage device 3, the accelerator operation amount detected by the accelerator position sensor 13, the vehicle speed detected by the vehicle speed sensor 14, the wheel speed detected by the wheel speed sensor 15, and the operation of the auxiliary machine 5. Receives the status and voltage / current supplied to the auxiliary equipment.

  Next, control performed by the integrated controller 9 will be described with reference to FIG. FIG. 2 is a flowchart showing a control apparatus for a hybrid vehicle in the present invention. In addition, this control is repeatedly performed every predetermined time (for example, 10 ms). In this control, the electric power supplied from the power storage device 3 to the drive motor 4 in order to compensate for the insufficient drive power when the driver requests acceleration does not exceed the limit drive force that allows the drive force of the drive motor 4 to be transmitted to the road surface. The calculation is performed within the range, and the electric power to be secured in the power storage device 3 when acceleration is requested is to be minimized.

  In step S10, the required drive power Pdrv is calculated based on the driver's accelerator operation amount and vehicle speed. The required drive power Pdrv is calculated by the control shown in the flowchart of FIG.

  That is, in step S11, the vehicle speed detected by the vehicle speed sensor 14 such as a magnetic or optical encoder is read.

  In step S12, the accelerator operation amount detected by the accelerator position sensor 13 is read.

  In step S13, the required driving force Fdrv of the vehicle is calculated based on the vehicle speed and the accelerator operation amount by searching the map of FIG. 4 showing the relationship between the vehicle speed, the accelerator operation amount, and the driving force. In the map of FIG. 4, the required driving force Fdrv increases as the vehicle speed and the accelerator operation amount increase, and is obtained in advance by experiments or the like.

  In step S14, a required driving power Pdrv0 that realizes the required driving force Fdrv is calculated. The required driving power Pdrv0 is calculated based on the following equation (1).

Pdrv0 = (Fdrv × Nm) / (Gf × Rtire × 1000) (1)
Here, Nm represents the rotational speed of the drive motor 4, Gf represents the reduction ratio of the final gear 6, and Rtire represents the effective radius of the drive wheel 7.

  Further, by searching the map of FIG. 5 showing the relationship between the rotational speed, torque, and operation efficiency of the drive motor 4, driving is performed based on the torque and rotational speed of the drive motor 4 when realizing the required drive power Pdrv0. The operating efficiency of the motor 4 is obtained. Based on this operating efficiency, the required drive power Pdrv, which is the power required to realize the required drive power Pdrv0, is calculated. Here, the torque of the drive motor 4 can be obtained by the following equation (2).

  Tdrv = (Fdrv × Rtire) / Gf (2)

  Further, the required drive power Pdrv may be obtained by the following equation (3).

Pdrv = Pdrv0 + Peff (3)
Here, Peff represents the power loss in the drive motor 4.

  Returning to FIG. 2, in step S <b> 20, the outputable power Pout of the power storage device 3 is calculated. The outputtable power Pout is an upper limit value of output power such that the terminal voltage of the power storage device 3 is lower than the lower limit voltage of the power storage device 3 and the power storage device 3 is not overdischarged, and is based on the following equation (4). Is calculated.

Pout = (Vmin × (Vo−Vmin)) / (R × 100) (4)
Here, Vmin is the lower limit voltage of the power storage device 3, Vo is the open circuit voltage of the power storage device 3, and R is the internal resistance of the power storage device 3. The open circuit voltage Vo of the power storage device 3 is calculated based on the state of charge (SOC) of the power storage device 3, and the SOC is calculated by integrating the charge / discharge current of the power storage device 3 detected by the power storage device controller 11. . Further, since the internal resistance R of the power storage device 3 varies depending on the temperature of the power storage device 3, the outputable power Pout can be calculated with higher accuracy by obtaining the relationship between the internal resistance R and temperature in advance through experiments or the like. it can.

  Returning to FIG. 2, in step S <b> 30, the power consumption Paux of the auxiliary machine 5 is estimated based on the operation state of the auxiliary machine 5 and the voltage / current supplied to the auxiliary machine 5.

  In step S40, the limit driving force Fmax is estimated based on the road surface friction coefficient μ. The limit driving force Fmax is the maximum driving force that can be transmitted from the driving wheel 7 to the road surface without causing over-rotation slip on the traveling road surface, and is calculated by the control shown in the flowchart of FIG.

  That is, in step S41, the road surface friction coefficient μ is estimated based on the wheel speed of each wheel. The road surface friction coefficient μ may be estimated based on, for example, a road surface friction coefficient gradient that is a gradient of a friction coefficient between a tire and a road surface, or may be estimated based on a braking torque gradient or a driving torque gradient with respect to a slip speed. Also good.

  Here, in the process of step S41, the road surface friction coefficient μ is not updated every calculation, but is updated when the road surface friction coefficient μ falls below a predetermined value by a predetermined number of times. Since the engine 2 causes a response delay, when the road surface friction coefficient μ continuously changes in a short time according to the road surface condition, the operating point of the generator 1 or the engine 2 is changed according to this change. In this case, the desired fuel consumption reduction effect cannot be obtained. Therefore, the driver's acceleration request can be reliably realized by updating only when the road surface friction coefficient μ is less than a predetermined value for a predetermined number of times (time) or more.

  In addition, by acquiring weather information around the area where the vehicle is traveling from a navigation system, the Internet, radio, etc., and determining whether or not the estimated road surface friction coefficient μ is a value representative of the region, the road surface on the road surface to be subsequently driven The friction coefficient μ may be predicted.

  Further, in a device in which the driver himself / herself determines the road surface condition, such as a snow mode switch, for example, the road surface friction coefficient μ may be estimated based on an input signal from the driver.

  In step S42, the limit driving force Fmax is calculated. The limit driving force Fmax is calculated by multiplying the load applied to the driving wheel 7 by the road surface friction coefficient μ.

  Returning to FIG. 2, in step S50, the margin drive power Prc is calculated. The surplus drive power Prc is power that is reserved in the power storage device 3 to make up for the generated power that is insufficient due to the response delay of the engine 2 when the driver requests acceleration, and the drive power of the drive motor 4 is the limit drive power Fmax. It is calculated by the control shown in the flowchart of FIG.

  That is, in step S51, the required driving force Faccmax at the time of the upper limit of the accelerator operation amount, that is, the full throttle is calculated. The required driving force Faccmax is searched based on the upper limit value of the accelerator operation amount and the vehicle speed with reference to the map of FIG.

  In step S52, the smaller one of the limit driving force Fmax and the required driving force Faccmax estimated in step S40 is selected, and the selected driving force is set as the limited required driving force Flmt. Here, the reason why the required driving force Faccmax at the time of full throttle is used is to quickly realize all the acceleration requests by the driver by ensuring the assumed maximum marginal driving power Prc.

  In step S53, the limited driving power Pdrvlmt that realizes the limited required driving force Flmt is calculated based on the following equation (5).

Pdrvlmt = (Flmt × Nm) / (Gf × Rtire × 1000) ..
・ (5)
Here, Nm uses the current rotational speed of the drive motor 4, but may be calculated taking into account the increase in rotational speed accompanying the increase in vehicle speed.

  In step S54, a surplus drive power Prc stored in the power storage device 3 is calculated in order to realize the limited drive power Pdrvlmt without delay according to the change in the driver's required drive force Fdrv. The margin driving power Prc is a difference between the generated power necessary to realize the limited driving power Pdrvlmt and the actual generated power, and a map is obtained in advance by experiments or the like. Thus, for example, if the electric power generated by the generator 1 is zero and the EV motor is running by the drive motor 4 using only the electric power supplied from the power storage device 4, the engine 2 is started and the generator 2 is started from a state where the output is zero. Since the generated electric power must be increased by driving, a larger amount of extra driving electric power Prc is required compared to when the engine is operating.

  Returning to FIG. 2, in step S60, the target generated power Pgen of the generator 1 is calculated. The target generated power Pgen is calculated by the control shown in the flowchart of FIG.

  That is, in step S61, it is determined whether or not the margin drive power Prc is equal to or less than the outputtable power Pout. If the margin drive power Prc is equal to or less than the outputtable power Pout, the process proceeds to step S62.

  In step S62, the target generated power Pgen is calculated based on the following equation (6).

Pgen = Pdrv + Paux− (Pout−Prc) (6)
Here, the power storage device 3 is discharged by (Pout−Prc) by subtracting, from the target generated power Pgen, power (Pout−Prc) obtained by subtracting the marginal drive power Prc from the outputtable power Pout. Thus, when the margin drive power Prc is equal to or less than the outputable power Pout, the power storage state (SOC) of the power storage device 3 is relatively high, so that the SOC is prevented from being excessive and the power storage device 3 By discharging as much as possible, the fuel consumption of the engine 2 that drives the generator 1 can be reduced and the fuel consumption can be improved. Moreover, the acceptability of regenerative electric power can be improved and the fuel consumption can be improved by reducing the SOC.

  On the other hand, if it is determined in step S61 that the surplus drive power Prc is greater than the outputtable power Pout, the process proceeds to step S63, and the target generated power is calculated based on the following equation (7).

Pgen = Pdrv + Paux (7)
Here, when the surplus drive power Prc is larger than the outputtable power Pout, the SOC of the power storage device 3 is relatively low. Therefore, the current total power consumption (Pdrv + Paux) is generated by the power generator 1 and the power storage device 3 Is not discharged.

  Returning to FIG. 2, in step S <b> 70, a target engine output at which the generated power of the generator 1 becomes the target generated power Pgen is calculated, and an engine torque command value is calculated by dividing this by the actual engine speed. The power generated by the generator 1 is controlled by controlling the engine 2 based on the engine torque command value.

  The operation of this embodiment will be described with reference to FIGS. FIG. 9 is a time chart showing the state of the vehicle in the conventional example. FIG. 10 is a time chart showing the state of the vehicle in this embodiment. (A) is the accelerator operation amount, (b) is the drive motor and engine power, and (c) is the charge / discharge power of the power storage device.

  When the accelerator operation amount increases at time t0 and a driver's acceleration request is generated (FIG. 9A), the required driving power Pdrv0 of the vehicle is increased and the output of the generator 1 is increased accordingly. The engine power increases (FIG. 9 (b)). However, the engine power rises with a delay from the required drive power Pdrv due to the response delay of the engine 2 (FIG. 9B).

  Therefore, the power stored in the power storage device 3 is supplied to the drive motor 4 until the engine power reaches the required drive power Pdrv and the required drive power Pdrv0 can be realized only by the output of the generator 1. The power is increased (FIG. 9C) to compensate for the insufficient work rate.

  The power storage device 3 stores the acceleration request from the driver, that is, the surplus drive power Prc that needs to be supplied to the drive motor 4 when the accelerator operation amount is the upper limit value. The output of the drive motor 4 can be increased to the required drive power Pdrv0 by the power supplied from the device 3. (FIGS. 9B and 9C).

  However, if the required driving force Fdrv when the accelerator operation amount increases is larger than the limit driving force Fmax, a part of the driving force generated by the driving motor 4 cannot be transmitted to the road surface, resulting in useless driving force. . The electric power stored in the power storage device 3 in preparation for the acceleration request is stored in excess as much as this wasteful driving force, so that the power that can be discharged from the power storage device 3 is reduced, and the EV travel mode (generator 1 Power generation by the engine 2 when the power of the drive motor 4 is insufficient with only the power supplied from the power storage device 3. The mode in which the machine 1 is driven and the power is supplied to the drive motor 4) is reduced, and the fuel efficiency improvement effect cannot be sufficiently obtained.

  Therefore, when the required driving force Fdrv is larger than the limit driving force Fmax as shown in FIG. 10, the required driving force Fdrv is limited to the limit driving force Fmax (FIG. 10 (b)).

  As a result, it is possible to reduce the power supplied to the drive motor 4 to compensate for the shortage of the engine power at the time of the acceleration request at time t0, and the marginal drive power Prc stored in the power storage device 3 is reduced (FIG. 10 ( c)).

  As described above, in the present embodiment, the marginal drive power Prc for supplementing the generated power that is insufficient with respect to the driver's acceleration request is calculated within a range in which the required drive force Fdrv does not exceed the limit drive force Fmax. Secure to 3. As a result, the electric power reserved in the power storage device 3 for the acceleration request can be suppressed to the minimum necessary, and the amount of discharge from the power storage device 3 can be increased accordingly. That is, the output of the engine 2 can be reduced. Therefore, fuel consumption can be improved by reducing the amount of fuel consumed while satisfying the driver's acceleration request.

  Further, when the SOC is relatively high such that the margin drive power Prc is equal to or less than the outputtable power Pout, the value obtained by subtracting the margin drive power Prc from the output possible power Pout is subtracted from the required drive power Pdrv to generate the generator 1. Target generated power Pgen is calculated.

  As a result, when the SOC is high, the amount of discharge of the power storage device 3 can be increased, and the generated power of the generator 1 can be suppressed accordingly, so that the SOC is prevented from becoming excessive and the generator 1 is driven. The fuel consumption of the engine 2 can be reduced and the fuel consumption can be improved. In addition, by increasing the discharge amount of the power storage device 3 and lowering the SOC, it is possible to improve receivable power acceptability and improve fuel efficiency.

  Furthermore, in a vehicle having an auxiliary machine 5 that receives power supply from the power storage device 3, when the SOC is relatively high such that the margin drive power Prc is equal to or less than the outputtable power Pout, the margin drive power Prc from the outputtable power Pout. Is subtracted from a value obtained by adding the required driving power Pdrv and the auxiliary machine power consumption Paux to calculate the target generated power Pgen of the generator 1.

  As a result, in the vehicle having the auxiliary machine 5 as well, when the SOC is high, the discharge amount of the power storage device 3 can be increased and the generated power of the generator 1 can be suppressed accordingly, so that the SOC is excessive. In addition, the fuel consumption of the engine 2 that drives the generator 1 can be reduced and the fuel consumption can be improved. In addition, by increasing the discharge amount of the power storage device 3 and lowering the SOC, it is possible to improve receivable power acceptability and improve fuel efficiency.

  Furthermore, since the vehicle according to the present embodiment includes the generator 1 that rotates by the driving force of the engine 2 to generate electric power, the responsiveness to the driver's acceleration request is improved compared to the vehicle that travels only by the driving force of the engine 2. Can be made.

  Furthermore, since the road surface friction coefficient μ is updated only when it continuously falls below a predetermined value by a predetermined number of operations, the road surface friction coefficient μ is continuously increased in a short time due to the influence of output noise of the wheel speed sensor 15 or the like. Even if it changes, the road surface friction coefficient μ is not updated, and the calculated limit driving force Fmax does not change. Therefore, it is possible to prevent the marginal driving power Prc from becoming insufficient and to reliably realize the driver's acceleration request. Can do.

  Furthermore, since the road surface friction coefficient μ is estimated based on the weather information of the area in which the vehicle is traveling, the road surface friction coefficient μ of the road surface to be driven later can be estimated in advance. The drive power Prc can be minimized.

(Second Embodiment)
FIG. 11 is an overall configuration diagram showing a control apparatus for a hybrid vehicle in the present embodiment. This embodiment is a case where the present invention is applied to a series hybrid vehicle having a fuel cell 16, and includes a fuel cell 16 instead of the engine 2 and the generator 1, which are the power generation device of the first embodiment, and further includes the generator 1. A fuel cell controller 17 for controlling the fuel cell 16 is provided instead of the generator controller 10 for controlling the fuel cell. The fuel cell 16 is controlled by the fuel cell controller 17 based on the target generated power command value output from the integrated controller 9. Other configurations are the same as those of the first embodiment shown in FIG.

  As described above, in the present embodiment, since the fuel cell 16 is used as the power generation device, the responsiveness to the increase in the amount of power generation is poor, but the marginal drive power Prc is previously stored within the range where the required drive force Fdrv does not exceed the limit drive force Fmax. Therefore, it is possible to improve the fuel efficiency by minimizing the electric power stored in the power storage device 3 while quickly realizing the driver's acceleration request.

  Various types of fuel cells 16 such as a solid polymer type, a phosphoric acid type, and a molten carbonate type can be applied. Further, hydrogen gas that is fuel gas may be stored in a hydrogen cylinder, or may be generated by reforming a raw material such as alcohol with a reformer.

(Third embodiment)
FIG. 12 is an overall configuration diagram showing a control apparatus for a hybrid vehicle in the present embodiment. In this embodiment, the present invention is applied to a parallel hybrid vehicle. In the present embodiment, the output shaft of the engine 2 and the input shaft of the drive motor 4, and the output shaft of the drive motor 4 and the input shaft of the continuously variable transmission 18 are connected to each other. The driving force of at least one of the engine 2 and the drive motor 4 is transmitted to the drive wheels 7 via the continuously variable transmission 18, the reduction gear 19 and the final gear 6.

  The continuously variable transmission 18 is a belt-type continuously variable transmission, and is supplied with pressure oil from the hydraulic device 20, and by changing the pulley width, the contact radius of the belt can be changed and the gear ratio can be changed. An oil pump (not shown) that generates hydraulic pressure in the hydraulic device 20 is driven by a motor 21.

  The transmission may be a toroidal continuously variable transmission or a stepped transmission. Further, a planetary gear may be used, and the engine 2 is coupled to the carrier, the drive motor 4 is coupled to the sun gear, the ring gear is coupled to the output shaft, and the rotation speed of the sun gear is changed, thereby making the rotation speed of the carrier and the ring gear stepless. Can be changed. In this case, even if the engine 2 generates a driving force, a state in which the driving force is not transmitted to the output shaft can be created depending on the gear ratio, so that a clutch is unnecessary.

  The drive motor 4 and the motor 21 are driven by inverters 22 and 23, respectively. The inverters 22 and 23 are connected to the power storage device 3 via a common DC link 24, convert the DC charging power of the power storage device 3 into AC power and supply it to the drive motor 4 and the motor 21. The AC power generated is converted into DC power to charge the power storage device 3. The drive motor 4 and the motor 21 are not limited to AC motors but may be DC motors. In this case, DC / DC converters are used instead of the inverters 22 and 23.

  For the power storage device 3, various types of batteries such as lithium ion batteries, nickel / hydrogen batteries, lead batteries, and electric double layer capacitors (power capacitors) may be used.

  The integrated controller 9 includes the voltage / current of the power storage device 3, the accelerator operation amount detected by the accelerator position sensor 13, the vehicle speed detected by the vehicle speed sensor 14, the wheel speed detected by the wheel speed sensor 15, and the power from the power storage device 3. The operating state of the auxiliary machine 5 that supplies power and the voltage / current supplied to the auxiliary machine 5 are received.

  Next, control performed by the integrated controller 9 will be described with reference to FIG. FIG. 13 is a flowchart showing a control apparatus for a hybrid vehicle in the present embodiment. In addition, this control is repeatedly performed every predetermined time (for example, 10 ms). In addition, parts that perform the same control as in the first embodiment are assigned the same reference numerals, and descriptions thereof are omitted as appropriate. In this control, as in the first embodiment, the power supplied from the power storage device 3 to the drive motor 4 is transmitted to the road surface from the power storage device 3 in order to compensate for the drive power that is insufficient when the driver requests acceleration. The calculation is performed within a range that does not exceed the possible limit driving force Fmax, and the electric power to be secured in the power storage device 3 when the acceleration is requested is to be minimized.

  In step S110, the required driving power Pdrv0 is calculated using the following equation (8) instead of the equation (1) used in step S10 of the first embodiment.

Pdrv0 = (Fdrv × Nm) / (Gf × Gcvt × Rtire × 1000) (8)
Here, Gcvt indicates the gear ratio of the continuously variable transmission 18.

  The control in steps S120 to S140 is the same as that in steps S20 to S40 in the first embodiment.

  In step S150, the margin drive power Prc is calculated using the following equation (9) instead of the equation (5) used in step S53 of the first embodiment.

  Pdrvlmt = (Flmt × Nm) / (Gf × Gcvt × Rtire × 1000) (9)

  In step S160, the target engine power Peng is calculated. The target engine power Peng is calculated by the control shown in the flowchart of FIG.

  That is, in step S161, it is determined whether or not the margin drive power Prc is equal to or less than the outputtable power Pout. If the margin drive power Prc is equal to or less than the outputtable power Pout, the process proceeds to step S162.

  In step S162, the target engine power Peng is calculated based on the following equation (10).

Peng = Pdrv0 + Paux− (Pout−Prc) (10)
Here, by subtracting the power (Pout−Prc) obtained by subtracting the marginal drive power Prc from the output possible power Pout from the target engine power Peng, the power storage device 3 is discharged by (Pout−Prc). . Thus, when the margin drive power Prc is equal to or less than the outputable power Pout, the power storage state (SOC) of the power storage device 3 is relatively high, so that the SOC is prevented from being excessive and the power storage device 3 By discharging as much as possible, the fuel consumption of the engine 2 can be reduced and fuel consumption can be improved. Moreover, the acceptability of regenerative electric power can be improved and the fuel consumption can be improved by reducing the SOC.

  On the other hand, when it is determined in step S161 that the surplus drive power Prc is larger than the outputtable power Pout, the process proceeds to step S163, and the target engine power Peng is calculated based on the following equation (11).

Peng = Pdrv0 (11)
Here, when the margin drive power Prc is larger than the outputable power Pout, the SOC of the power storage device 3 is relatively low. Therefore, the required drive power Pdrv is generated by the engine 2 and only the auxiliary machine power consumption Paux is stored. 3 is discharged.

  Returning to FIG. 13, in step S170, an engine torque command value at which the power of the engine 2 becomes the target engine power Peng is calculated, and the engine 2 is controlled based on the engine torque command value.

  In step S180, an actual engine power ratio rPeng is calculated. The actual engine power rPeng is calculated by multiplying the engine torque calculated based on the fuel injection amount, the air flow rate, the ignition timing, and the like with the engine rotation speed.

  In step S190, the drive motor power Pm is calculated. The drive motor power Pm is calculated based on the following equation (12).

Pm = Pdrv0−rPeng (12)
In step S200, a target motor torque Tm necessary for realizing the drive motor power Pm is calculated. The target motor torque Tm is calculated based on the following equation (13).

Tm = Pm / 1000 / Neng (13)
Here, Neng indicates the engine rotation speed.

  In step S210, the power supplied from the power storage device 3 to the drive motor 4 is controlled so that the torque of the drive motor 4 becomes the target motor torque Tm.

  As described above, in the present embodiment, the marginal drive power Prc for supplementing the generated power that is insufficient with respect to the driver's acceleration request is calculated within a range in which the required drive force Fdrv does not exceed the limit drive force Fmax. Secure to 3. As a result, the electric power reserved in the power storage device 3 at the time of an acceleration request can be suppressed to the minimum necessary, and the amount of discharge from the power storage device 3 can be increased accordingly. The power of the engine 2 can be reduced by increasing the power. Therefore, fuel consumption can be improved by reducing the amount of fuel consumed while satisfying the driver's acceleration request.

  Further, when the SOC is relatively high such that the margin drive power Prc is equal to or less than the outputtable power Pout, the value obtained by subtracting the margin drive power Prc from the output possible power Pout is subtracted from the required drive power Pdrv to generate the generator 1. Target generated power Pgen is calculated.

  As a result, when the SOC is high, the discharge amount of the power storage device 3 can be increased, and the engine power can be reduced accordingly, so that the SOC is prevented from becoming excessive and the fuel consumption of the engine 2 is reduced. It can reduce and improve fuel consumption. In addition, by increasing the discharge amount of the power storage device 3 and lowering the SOC, it is possible to improve receivable power acceptability and improve fuel efficiency.

  Furthermore, in a vehicle having an auxiliary machine 5 that receives power supply from the power storage device 3, when the SOC is relatively high such that the margin drive power Prc is equal to or less than the outputtable power Pout, the margin drive power Prc from the outputtable power Pout. Is subtracted from a value obtained by adding the required driving power Pdrv and the auxiliary machine power consumption Paux to calculate the target generated power Pgen of the generator 1.

  As a result, in the vehicle having the auxiliary machine 5 as well, when the SOC is high, the discharge amount of the power storage device 3 can be increased and the power of the engine can be reduced accordingly, so that the SOC is excessive. In addition, the fuel consumption of the engine 2 that drives the generator 1 can be reduced and fuel consumption can be improved. In addition, by increasing the discharge amount of the power storage device 3 and lowering the SOC, it is possible to improve receivable power acceptability and improve fuel efficiency.

  The present invention is not limited to the embodiment described above, and various modifications and changes can be made within the scope of the technical idea, and it is obvious that these are equivalent to the present invention.

It is a whole block diagram which shows the control apparatus of the hybrid vehicle in 1st Embodiment. It is a flowchart which shows control of the control apparatus of the hybrid vehicle in 1st Embodiment. It is a flowchart which shows the control which calculates request | requirement drive electric power. It is a map which shows the relationship between a vehicle speed, an accelerator opening degree, and a request | requirement driving force. It is a map which shows the efficiency characteristic of a drive motor. It is a flowchart which shows the control which estimates a limit driving force. It is a flowchart which shows the control which calculates surplus drive electric power. It is a flowchart which shows the control which calculates target generated electric power. It is the time chart which showed the state of the vehicle in a prior art example. It is a time chart which showed the state of vehicles in this embodiment. It is a whole block diagram which shows the control apparatus of the hybrid vehicle in 2nd Embodiment. It is a whole block diagram which shows the control apparatus of the hybrid vehicle in 3rd Embodiment. It is a flowchart which shows control of the control apparatus of the hybrid vehicle in 3rd Embodiment. It is a flowchart which shows the control which calculates a target engine work rate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Generator 2 Engine 3 Power storage device 4 Drive motor 5 Auxiliary machine 6 Final gear 7 Drive wheel 8 Engine controller 9 Integrated controller 10 Generator controller 11 Power storage device controller 12 Drive motor controller 13 Accelerator operation amount sensor 14 Vehicle speed sensor 15 Wheel speed sensor 16 Fuel Cell 17 Fuel Cell Controller 18 Continuously Variable Transmission 19 Deceleration Device 20 Hydraulic Device 21 Motor 22 Inverter 23 Inverter 24 DC Link

Claims (10)

A drive motor that generates a driving force to be transmitted to the drive wheels of the vehicle;
A power storage device for storing electric power to be supplied to the drive motor;
A power generator that generates power to be supplied to the drive motor and power stored in the power storage device;
A required driving power calculating means for calculating a required driving power for realizing the required driving force required for the vehicle;
An outputable power calculating means for calculating outputable power that is outputable power of the power storage device;
Limit driving force estimating means for estimating an upper limit value of driving force that can be transmitted from the driving wheel to the road surface based on a road surface state while the vehicle is traveling;
When the required driving force required for the vehicle increases, the electric power for supplementing the generated power that is insufficient until the output power of the power generator increases to the target generated power, which is supplied from the power storage device to the drive motor Margin driving power calculation means for calculating margin driving power that is power to be
The margin driving power is calculated based on the upper limit value of the driving force calculated by the limit driving force estimating means, and the target of the power generation device is calculated based on the margin driving power, the output possible power, and the required driving power. Target generated power calculating means for calculating generated power;
Generated power control means for controlling the generated power of the power generator so that the generated power of the power generator becomes the target generated power;
A control apparatus for a hybrid vehicle, comprising:   The target generated power calculating means calculates a target generated power by subtracting a value obtained by subtracting the margin driving power from the output possible power from the required driving power when the margin driving power is equal to or less than the output possible power. The control apparatus for a hybrid vehicle according to claim 1, wherein: Auxiliary power consumption estimation means for estimating power consumed by an auxiliary machine that is operated by power supplied from the power storage device,
The target generated power calculating means adds the required driving power and the auxiliary machine power consumption to a value obtained by subtracting the margin driving power from the output possible power when the margin driving power is equal to or less than the output possible power. 2. The control apparatus for a hybrid vehicle according to claim 1, wherein the target generated power is calculated by subtracting from the calculated value.   4. The hybrid vehicle control device according to claim 1, wherein the power generator is a generator that generates electric power by being rotated by a driving force of an engine. 5.   The control device for a hybrid vehicle according to any one of claims 1 to 3, wherein the power generation device is a fuel cell. An engine and a drive motor for generating a driving force transmitted to the driving wheels of the vehicle;
A power storage device for storing electric power to be supplied to the drive motor;
A required driving power calculating means for calculating a required driving power for realizing the required driving force required for the vehicle;
An outputable power calculating means for calculating outputable power that is outputable power of the power storage device;
Limit driving force estimating means for estimating an upper limit value of driving force that can be transmitted from the driving wheel to the road surface based on a road surface state while the vehicle is traveling;
When the required driving force required for the vehicle increases, the electric power for supplementing the generated power that is insufficient until the output power of the power generator increases to the target generated power, which is supplied from the power storage device to the drive motor Margin driving power calculation means for calculating margin driving power that is power to be
The marginal driving power is calculated based on the upper limit value of the driving force calculated by the limit driving force estimating means, and the target engine of the engine is calculated based on the marginal driving power, the output power and the required driving power. Target engine power calculation means for calculating the power, and
Engine power control means for controlling the engine power so that the engine power becomes the target engine power;
A control apparatus for a hybrid vehicle, comprising:   The target engine power calculation means subtracts, from the required drive power, a target engine power by subtracting a value obtained by subtracting the margin drive power from the output power when the margin drive power is equal to or less than the output power. The hybrid vehicle control device according to claim 6, wherein: Auxiliary power consumption estimation means for estimating power consumed by an auxiliary machine that is operated by power supplied from the power storage device,
The target engine power calculation means calculates the required drive power and the auxiliary machine power consumption by subtracting the margin drive power from the output power when the margin drive power is less than or equal to the output power. The hybrid vehicle control device according to claim 6, wherein the target engine power is calculated by subtracting from the added value. A friction coefficient estimating means for estimating a friction coefficient between the drive wheel and the road surface, and updating the friction coefficient when the friction coefficient is continuously lower than a predetermined value by a predetermined number of operations;
The hybrid vehicle according to any one of claims 1 to 8, wherein the limit driving force estimating means calculates a limit driving force by multiplying the friction coefficient and a load applied to the driving wheel. Control device. Friction coefficient estimation means for acquiring weather information of a region where the vehicle is traveling, and estimating a friction coefficient between the drive wheel and a road surface based on the weather information,
The hybrid vehicle according to any one of claims 1 to 8, wherein the limit driving force estimating means calculates a limit driving force by multiplying the friction coefficient and a load applied to the driving wheel. Control device.

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