JP2010130862A - Driving force control device of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a driving force control device of a vehicle for suppressing vibration of the vehicle by an accelerator opening APO. <P>SOLUTION: A control means includes a delay processing means which performs delay processing to an accelerator signal or sets a dead zone to the accelerator signal. The delay processing means performs the delay processing to the accelerator signal or sets the dead zone to the accelerator signal, based on at least any one of the accelerator signal, a vehicle speed, and a battery residual amount. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a driving force control device for a vehicle that obtains driving force by an engine and an electric motor.

Conventionally, in the vehicle described in Patent Document 1, a delay filter is applied to the accelerator signal so that the vehicle does not follow an excessive accelerator operation caused by a driver's error.
JP 2006-144650 A

  However, in a vehicle driven by a motor, a linear driving force is obtained for an accelerator operation by taking advantage of the high response of the motor. However, when the above conventional technology is applied to a vehicle using a motor as a power source, the accelerator by the driver When the opening degree APO fluctuates unintentionally, the fluctuation of the accelerator opening degree APO is reflected in the driving force through the delay filter, which causes a problem of vehicle vibration.

  For example, the driver's foot stepping on the accelerator pedal also vibrates due to the vibration of the vehicle when traveling on a rough road, and this vibration is reflected in the driving force. Further, in order to reduce this vibration, the gain of the delay filter may be changed, but the response of the driving force with respect to the accelerator opening APO is reduced.

  Further, the vibration of the vehicle due to the change in the accelerator opening APO does not occur in the entire vehicle speed region and the entire accelerator operation region, and the driver does not generate the unintended vibration of the accelerator opening APO. Therefore, if the delay filter processing is uniformly performed in the entire vehicle speed region and the entire accelerator operation region, the delay filter processing is performed even in the region where the delay filter processing is not originally required, and the driving force response becomes unbalanced.

  If the delay filter processing is uniformly performed, the driving force response to the accelerator opening APO is deteriorated, and the merit of the motor-driven vehicle that the driving force responds linearly to the accelerator opening APO cannot be utilized.

  Furthermore, it is possible to determine the steady state of the vehicle and apply a delay filter only when it is determined to be a steady state, but when determining the steady state when the accelerator opening is equal to or less than a predetermined value within a certain time, Since a time lag occurs from the start of the steady state determination until the result is obtained, vibration due to the accelerator opening APO occurring during that time cannot be prevented.

  The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a vehicle driving force control device that suppresses vibrations of the vehicle due to the accelerator opening APO.

  In order to achieve the above object, in the present invention, the control means includes delay processing means for executing delay processing on the accelerator signal or setting a dead zone for the accelerator signal, the delay processing means comprising an accelerator signal, a vehicle speed, Alternatively, delay processing is executed for the accelerator signal based on at least one of the remaining battery levels, or a dead zone is set for the accelerator signal.

  Therefore, it is possible to provide a vehicle driving force control device that suppresses vehicle vibration caused by the accelerator opening APO.

  Hereinafter, the best mode for realizing a driving force control apparatus for a vehicle according to the present invention will be described based on an embodiment shown in the drawings.

[System configuration]
FIG. 1 is a system configuration diagram of a hybrid vehicle to which a driving force control device for a vehicle of the present application is applied. The hybrid vehicle includes an engine E, first and second electric motors MG1 and MG2, first and second inverters 1a and 1b, a power split mechanism 3, a battery 2, a controller CU, a left rear wheel RL (drive wheel), and a right rear wheel. It has RR (driving wheel). Note that FL is the left front wheel and FR is the right front wheel.

  The power split mechanism 3 is connected to the engine E via the input shaft IN and is connected to the first and second electric motors MG1 and MG2, and is controlled to be engaged / released based on a control command from the controller CU. The first electric motor MG1 is connected only to the power transmission mechanism 3, and the second electric motor MG2 is connected to the drive wheels RL and RR via the power transmission mechanism 3 and the output shaft OUT.

  The first and second motors MG are synchronous motors in which a permanent magnet is embedded in a rotor and a stator coil is wound around a stator. In driving, the first and second inverters 1a and 1b are controlled based on a control command from the controller CU.

  The electric motor MG is driven to rotate by receiving power supplied from the battery 2 and can function as a generator when it is rotated by an external force to charge the battery 2.

  The controller CU receives power supply from the battery 2, and based on the accelerator opening APO from the accelerator pedal 4 and the vehicle speed V from the vehicle speed sensor 5, the first and second electric motors MG1, MG2, first, second inverter 1a, 1b, the power split mechanism 3 and the engine E are controlled to execute each travel mode (EV mode, HEV mode).

[Driving mode]
The hybrid vehicle of the present application has two driving modes, EV mode (running only with the driving force of the electric motor MG) and HEV mode (using both the driving force of the electric motor MG and the engine E) according to the fastening / release state of the power split mechanism 3. .

(EV mode)
When the second electric motor MG2 and the engine E are released by the power split mechanism 3, the driving force of the engine E is not transmitted to the output shaft OUT, and the vehicle runs using only the power of the second electric motor MG2 as a power source. EV mode is performed. At this time, the first electric motor MG1 and the second electric motor MG2 may be fastened by the power split mechanism 3, and the driving forces of both the first and second electric motors MG1, MG2 may be transmitted to the output shaft OUT.

(HEV mode)
When the power split mechanism 3 is in the engaged state, the driving force of the engine E is transmitted to the output shaft OUT via the second electric motor MG2, and the HEV mode that uses the driving force of the engine E in addition to the second electric motor MG2 is set. . Also in this case, the driving force of both the first and second electric motors MG1 and MG2 may be transmitted to the output shaft OUT by the power split mechanism 3.

[Control configuration]
FIG. 2 is a control block diagram of the driving force in the controller CU. Based on the driving force map 110. A delay filter process is executed for the accelerator opening APO to calculate an output shaft driving force, and the multiplication unit 120 calculates the target driving force by multiplying the output shaft driving force by the vehicle speed.

The driving force map 110 is
・ Accelerator opening APO
・ Vehicle speed V
・ Remaining battery 2 ・ Accelerator opening change amount ΔAPO per unit time
-Number of inflection points of driving force calculated based on accelerator opening APO and vehicle speed V (the point where the sign of the time change rate of driving force changes)-At least one of the deviations between inflection points A time constant is calculated based on this, and a delay filter process is performed based on this time constant to calculate the output shaft driving force (details will be described later).

[Driving force control processing]
FIG. 3 is a flowchart of the driving force control. Hereinafter, each step will be described. Hereinafter, a small accelerator opening APO that is not intended by the driver is defined as noise. Further, the vehicle travel mode in the flow of FIG. 3 is the EV mode, and the vehicle travels only by the driving force of the second electric motor MG2.

  In step S1, the presence / absence of noise in the accelerator opening APO and the deviation A are detected, and the process proceeds to step S2 (see FIG. 6 described later).

In step S2, the time constant of the delay filter applied to the accelerator opening APO is determined based on the detected noise, and the process proceeds to step S3. If no noise is detected, the delay filter is not set. Although the time constant is set in the first embodiment, a fixed dead zone may be set for the detected value of the accelerator opening APO.
The time constant of the delay filter is calculated from the noise frequency-time constant map (see FIG. 4) of the accelerator opening APO and the battery remaining amount-time constant map (see FIG. 5). The noise frequency-time constant map includes a plurality of maps depending on the vehicle speed V. One or more optimum maps are selected based on the detected accelerator opening APO, vehicle speed V, and the remaining amount of the battery 2, and a time constant is calculated.
Since a plurality of time constants are calculated when a plurality of maps are selected, the final time constant is determined from the plurality of time constants. An average value or the like may be used to calculate the final time constant, or each time constant may be weighted for calculation. A maximum value or a minimum value among a plurality of time constants may be used.

  Since the driver's foot stepping on the accelerator pedal also vibrates due to the vibration of the vehicle when traveling on a rough road, this vibration is reflected in the driving force. Further, in order to reduce this vibration, the gain of the delay filter may be changed, but the response of the driving force with respect to the accelerator opening APO is reduced. Therefore, by using at least one of the plurality of time constant maps, an optimal time constant is determined in accordance with the vehicle state, and vehicle vibration based on unintended fluctuations in the accelerator opening APO is reduced.

  Further, the vibration of the vehicle due to the change in the accelerator opening APO does not occur in the entire vehicle speed region and the entire accelerator operation region, and the driver does not generate the unintended vibration of the accelerator opening APO. Therefore, if the delay filter processing is uniformly performed in the entire vehicle speed range and the entire accelerator operation region, the delay filter processing is also performed in the region that originally does not need the delay filter processing, and the driving force response becomes unbalanced. By using at least one of these time constant maps, an optimal time constant is determined in accordance with the vehicle state, and the vibration is suppressed and the vehicle vibration based on the fluctuation of the accelerator opening APO is suppressed.

  Further, if the delay filter processing is uniformly performed, the driving force response to the accelerator opening APO deteriorates and the driving force responds linearly to the accelerator opening APO. By using at least one of the time constant maps, an optimal time constant according to the vehicle state is determined.

Furthermore, it is possible to determine the steady state of the vehicle and apply a delay filter only when it is determined to be a steady state, but when determining the steady state when the accelerator opening is equal to or less than a predetermined value within a certain time, Since a time lag occurs from the start of the steady state determination until the result is obtained, vibration due to the accelerator opening APO occurring during that time cannot be prevented. Therefore, by using at least one of a plurality of time constant maps, an optimal time constant is determined according to the vehicle state without determining whether or not the vehicle is in a steady state, and unintentional accelerator opening APO fluctuations are determined. To reduce vehicle vibration.

  In step S3, it is determined whether or not the noise deviation A detected in step S1 is within a predetermined range. If YES, the process proceeds to step S4, and if NO, the process proceeds to step S7. Details will be described later (see FIG. 6: Step S105).

In step S4, it is determined whether the remaining amount of the battery 2 is equal to or greater than a predetermined value. If YES, the process proceeds to step S4, and if NO, the process proceeds to step S7.
When the remaining amount of the battery 2 is small, the driving force of the first and second electric motors MG1 and MG2 becomes small, and even when noise of the accelerator opening APO occurs, vehicle body vibrations that make the driver feel uncomfortable do not occur. Therefore, in the first embodiment, when the remaining amount of the battery 2 is 40% or less, the process proceeds to step S7 to cancel the selection of the delay filter and improve the response of the driving force to the accelerator operation.

In step S5, it is determined whether vehicle speed V ≧ predetermined value. If YES, the process proceeds to step S6, and if NO, the process proceeds to step S7.
If a delay filter is applied to the accelerator opening APO when the vehicle speed is low (for example, 40 km / h or less), such as when parking or entering a garage, the driving force response to the accelerator opening APO changes suddenly and the operability deteriorates. . Therefore, it progresses to step S7 and the selection of a delay filter is cancelled | released.

In step S6, it is determined whether or not accelerator opening APO ≧ predetermined value. If YES, the process proceeds to step S8, and if NO, the process proceeds to step S7.
If the accelerator opening APO is equal to or less than a predetermined value, the driver's intention is considered to be a normal driving intention that is not sudden acceleration or rapid deceleration. it is conceivable that. If a delay filter is applied to the accelerator opening APO when there is an intention to suddenly accelerate or decelerate, the driver feels uncomfortable. Therefore, if the accelerator opening APO is greater than or equal to a predetermined value, the control proceeds to step S7 and the delay filter is applied. Is released.

  In step S7, the control for applying the delay filter is canceled, and the process proceeds to step S8.

  In step S8, the driving force of the second electric motor MG2 is linearly changed to the target driving force calculated based on the accelerator opening APO, and the process proceeds to step S9. Here, the gradient of the linear change is set to be small, and the driving force is gently changed to suppress a sudden change in the vehicle behavior.

In step S9, it is determined whether acceleration determination or deceleration determination of the vehicle is made. If YES, the process proceeds to step S10, and if NO, the control is terminated.
If a delay filter is applied to the accelerator opening APO when there is an intention to accelerate or decelerate, the driver feels uncomfortable. If the accelerator opening APO is greater than or equal to a predetermined value, the process proceeds to step S10 and the delay filter is applied. Release control.
Further, the process proceeds to step S11, where the driving force of the second electric motor MG2 is immediately changed to the target value corresponding to the accelerator opening APO, and the responsiveness of the driving force is ensured to improve the vehicle controllability.

  In step S10, the control for applying the delay filter is canceled, and the process proceeds to step S11.

  In step S11, the driving force of the second electric motor MG2 is immediately changed to the target value corresponding to the accelerator opening APO, and the control is finished.

[Noise detection flow]
FIG. 6 is a noise detection flow (step S1 in FIG. 3).

  In step S101, it is determined whether or not the measurement time of the timer for performing noise detection ≧ predetermined time T. If YES, the process proceeds to step S105, and if NO, the process proceeds to step S102.

  In step S102, it is determined whether or not there is an inflection point of the accelerator opening APO. If there is an inflection point, the process proceeds to step S103, and if not, the control is terminated.

In step S103, the number n of inflection points generated within the measurement time is integrated, and the process proceeds to step S104.
By limiting the inflection point integration within the predetermined time T, even if erroneous detection of the inflection point occurs frequently, the integration is temporarily stopped after the predetermined time T has elapsed. Therefore, erroneous inflection point values are not accumulated beyond the predetermined time T, and deterioration of control accuracy is avoided.

  In step S104, the absolute value of the inflection point is stored, and the control is terminated.

In step S105, the number n of inflection points is calculated. If there are a plurality of inflection points, the deviation A of the absolute value of each inflection point is calculated, and the process proceeds to step S106.
Here, when the deviation A of the accelerator opening APO is within the range of the upper limit A0 (eg, the range of A0 is the accelerator opening change 0.5% to 2%), the delay filter process is performed. If the deviation A is 0.5% or less, the driver's intention is considered to be extremely low, and if it is 2% or more, acceleration is considered.
If a delay filter is applied to the accelerator opening APO when there is an intention of acceleration or extremely low speed, the driver feels uncomfortable. Therefore, if the deviation of the accelerator opening APO is outside the predetermined range, NO determination is made in step S3 of FIG. Then, the process proceeds to step S7 to cancel the selection of the delay filter.

  In step S106, the noise detection timer is cleared and the control is terminated.

[Change in driving force control over time]
FIG. 7 is a time chart of driving force control. FIG. 8 is an enlarged view of FIG. Each of the lengths of the vertical axes of the regions D1 to D5 (enclosed with bold lines) in FIG. 8 is the upper limit value A0 of the difference A between the inflection points.

The frequency f of the noise of the accelerator opening APO is f = n / (2T) where n is the number of inflection points and T is the predetermined time.
It is defined as Based on this noise frequency f, a time constant is calculated using the map of FIG.

  Here, the difference A between the inflection points is calculated in step S105 in FIG. 6. When the value of the difference A exceeds the upper limit A0, the accelerator opening APO is changed based on the driver's intention instead of noise. Consider it a thing. In this case, noise determination is not performed, and the control for applying the delay filter is canceled (FIG. 3: steps S3 → S7).

  Only when an inflection point is generated within the range of the upper limit value A0, it is determined as noise of the accelerator opening APO (see FIGS. 8 and 9). 8 and 9, the deviation A between the inflection points is below the upper limit A0, and noise determination is performed.

In FIG. 8, the inflection point is indicated by N. In the region D2, the number of inflection points N is n = 4, and the noise frequency f is f = 4 / (2T) = 2 / T.
It becomes. Based on this value, a time constant is calculated using the map of FIG. 4 and a delay filter is applied.

[Effect of Example 1]
(1) First and second electric motors MG1, MG2,
Drive wheels RL and RR driven by the first and second electric motors MG1 and MG2,
A battery 2 for supplying power to the first and second electric motors MG1, MG2,
In a vehicle driving force control device including a controller CU (control means) for driving and controlling the first and second electric motors MG1 and MG2 based on an accelerator opening APO (accelerator signal) by an accelerator operation of a driver,
The controller CU includes delay processing means (steps S1 to S11) for executing a delay process for the accelerator opening APO or setting a dead zone for the accelerator opening APO.
The delay processing means executes a delay process for the accelerator opening APO or sets a dead zone for the accelerator opening APO based on at least one of the accelerator opening APO, the vehicle speed V, and the battery 2 remaining amount. It was decided to.

  As a result, it is possible to provide a vehicle driving force control device that suppresses the vibration of the vehicle due to the vibration of the accelerator opening APO that is not intended by the driver.

  (2) The delay processing means includes the number n of inflection points of the accelerator opening APO, the deviation A between the inflection points, the accelerator opening APO, the amount of change in the accelerator opening APO, the vehicle speed V, and the remaining battery 2 amount. Among them, a map based on at least one is provided, and a delay process is executed for the accelerator opening APO based on this map, or a dead zone is set for the accelerator opening APO.

  As a result, an optimal time constant according to the vehicle state can be determined, and vehicle vibration based on unintended fluctuations in the accelerator opening APO can be reduced.

  (3) When the vehicle speed V becomes a predetermined value or less, the delay processing means cancels the execution of the delay processing or the setting of the dead zone.

  If a delay filter is applied to the accelerator opening APO when the vehicle speed is low (for example, 40 km / h or less), such as when parking or entering a garage, the driving force response to the accelerator opening APO changes suddenly and the operability deteriorates. . Therefore, it is possible to avoid deterioration in operability by canceling the selection of the delay filter or the setting of the dead zone.

  (4) The delay processing means cancels the execution of the delay process or the setting of the dead zone when the remaining amount of the battery 2 becomes a predetermined value or less.

  When the remaining amount of the battery 2 is small, the driving force of the first and second electric motors MG1 and MG2 becomes small, and even when noise of the accelerator opening APO occurs, vehicle body vibrations that make the driver feel uncomfortable do not occur. Therefore, when the remaining amount of the battery 2 is equal to or less than the predetermined value, the selection of the delay filter or the setting of the dead zone can be canceled to improve the responsiveness of the driving force to the accelerator operation.

  (5) The delay processing means cancels the execution of the delay process or the setting of the dead zone when one or both of the accelerator opening APO and the change amount of the accelerator opening APO become a predetermined value or more. did.

  If accelerator opening APO or accelerator opening change amount ΔAPO is equal to or smaller than a predetermined value, the driver's intention is considered to be rapid acceleration or rapid deceleration. If a delay filter is applied to the accelerator opening APO when there is an intention to suddenly accelerate or decelerate, the driver feels uncomfortable. Therefore, if the accelerator opening APO is greater than or equal to a predetermined value, the control proceeds to step S7 and the delay filter is applied. , And the driver's uncomfortable feeling can be reduced.

  (6) The driving force of the first and second electric motors MG1 and MG2 when the delay processing means cancels the execution of the delay processing or the setting of the dead zone based on one or both of the vehicle speed V and the remaining battery 2 Was linearly changed to the target value.

  The driving force can be changed loosely by the linear change, and a sudden change in the vehicle behavior can be suppressed.

  (7) When the delay processing means cancels the execution of the delay processing or the setting of the dead zone based on one or both of the accelerator opening APO and the change amount of the accelerator opening APO, the first and second electric motors MG1 The driving force of MG2 is immediately changed to the target value.

  By canceling the delay process immediately, the responsiveness of the driving force can be secured and the vehicle controllability can be improved.

  (8) The number n of inflection points of the accelerator opening APO is a value obtained by integrating the number of inflection points generated within a predetermined time.

  By limiting the inflection point integration within the predetermined time T, even if erroneous detection of the inflection point occurs frequently, the integration is temporarily stopped after the predetermined time T has elapsed. For this reason, erroneous inflection point values are not accumulated beyond the predetermined time T, and deterioration of control accuracy can be avoided.

  (9) When the deviation A between the inflection points is within a predetermined range (for example, when the upper limit value A0 = 2%, the accelerator opening change is 0.5% to 2%), The dead zone was set.

  If the deviation A is small, the driver's intention is extremely low speed, and if the deviation A is greater than or equal to the upper limit A0, it is considered acceleration. If a delay filter is applied to the accelerator opening APO when there is an intention of acceleration or extremely low speed, the driver feels uncomfortable. Therefore, if the deviation of the accelerator opening APO is outside the predetermined range, the selection of the delay filter is canceled and the driver feels uncomfortable. Can be reduced.

  As mentioned above, although the control apparatus of the hybrid vehicle of this invention has been demonstrated based on the Example, about a specific structure, it is not restricted to this Example, The summary of the invention which concerns on each claim of a claim As long as they do not deviate, design changes and additions are permitted.

(Other examples)
For example, you may apply to the electric vehicle which does not have an engine like FIG. In FIG. 9, the driving force of the electric motor MG is transmitted to the drive wheels RL and RR via the transmission AT (the control configuration of the controller CU and the like is omitted). Even in such an electric vehicle, the same effect as in the first embodiment can be obtained.

1 is a system configuration diagram of a hybrid vehicle. It is a control block diagram of the driving force in a controller. It is a flowchart of driving force control. It is a noise frequency-time constant map of accelerator opening APO. It is a battery remaining amount-time constant map. It is a noise detection flow. It is a time chart of driving force control. FIG. 8 is an enlarged view of FIG. 7. This is another embodiment.

Explanation of symbols

2 battery
APO accelerator opening (accelerator signal)
CU controller (control means)
MG1, MG2 First and second electric motors RL, RR Rear wheels (drive wheels)
S1-S11 Delay processing means

Claims (9)

An electric motor,
Drive wheels driven by the electric motor;
A battery for supplying power to the motor;
In a vehicle driving force control device comprising: a control means for driving and controlling the electric motor based on an accelerator signal generated by a driver's accelerator operation;
The control means includes delay processing means for executing a delay process for the accelerator signal or setting a dead zone for the accelerator signal,
The delay processing means performs delay processing on the accelerator signal based on at least one of the accelerator signal, the vehicle speed, and the remaining battery level, or sets a dead zone for the accelerator signal. A vehicle driving force control device. The vehicle driving force control apparatus according to claim 1,
The delay processing means includes at least one of the number of inflection points of the accelerator signal, the deviation between the inflection points, the accelerator signal, the change amount of the accelerator signal, the vehicle speed, and the remaining battery level. A vehicle driving force control apparatus comprising: a map based on the map; and delay processing for the accelerator signal based on the map or setting a dead zone for the accelerator signal. In the vehicle driving force control device according to claim 1 or 2,
The vehicle driving force control device according to claim 1, wherein the delay processing unit cancels the execution of the delay processing or the setting of the dead zone when the vehicle speed becomes a predetermined value or less. In the vehicle driving force control device according to claim 1 or 2,
The delay processing means cancels the execution of the delay process or the setting of the dead zone when the remaining amount of the battery becomes a predetermined value or less. In the driving force control device according to claim 1 or 2,
The delay processing means cancels the execution of the delay processing or the setting of the dead zone when one or both of the accelerator signal and the change amount of the accelerator signal are equal to or greater than a predetermined value. A vehicle driving force control device. In the vehicle driving force control device according to claim 3 or 4,
The delay processing means linearly changes the driving force of the motor to a target value when the execution of the delay processing or the setting of the dead zone is canceled based on one or both of the vehicle speed and the remaining battery level. A driving force control device for a vehicle, characterized in that In the vehicle driving force control device according to claim 5,
When the delay processing unit cancels the execution of the delay processing or the setting of the dead zone based on one or both of the accelerator signal and the change amount of the accelerator signal, the delay processing means immediately sets the driving force of the motor to a target value. A driving force control device for a vehicle characterized in that In the vehicle driving force control device according to claim 2,
The number of inflection points of the accelerator signal is a value obtained by integrating the number of inflection points generated within a predetermined time. The vehicle driving force control apparatus according to claim 8,
When the deviation between the inflection points is within a predetermined range, the delay processing means performs the delay processing or sets the dead zone.

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