Abstract:
To provide a drive control device of a moving body capable of increasing a regeneration amount without hindering a driver&#39;s brake operation and causing too much deceleration. A drive control device of a moving body that updates a regenerative pattern of a driving motor of the moving body including a brake that generates a braking force by being linked to an operation amount of a brake pedal, the drive control device including an external world information acquisition unit that acquires external world information and a brake detector that detects ON/OFF of the brake, wherein when the brake detector detects ON, the regenerative pattern is changed based on the external world information acquired by the external world information acquisition unit such that a braking distance only decreases.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a method of regenerative control using an external recognition sensor of a motor vehicle. 
       BACKGROUND ART 
       [0002]    In recent years, motor vehicles that travel by wheels being driven by a motor and/or an engine have been developed. 
         [0003]    Such a motor vehicle is accelerated by torque of an engine being assisted by a motor or the motor alone during acceleration and recovers energy by generating power using the motor during deceleration. 
         [0004]    Accordingly, energy efficiency can be improved by assisting torque using the motor or using the motor alone in an area where energy efficiency of the engine is low and energy recovered during deceleration can be used for acceleration so that fuel efficiency can be improved. 
         [0005]    In addition, automatic braking control and automobile speed control devices using an external recognition sensor to soften the impact during collision and reduce driver&#39;s driving loads have been proposed. 
         [0006]    Such an automatic braking control device can automatically decelerate by detecting the distance from the vehicle to an obstacle and a relative speed therebetween through the external recognition sensor and calculating appropriate timing from the detection results. 
         [0007]    In the meantime, for example, in the invention described in PTL1, a target driving force is determined based on the vehicle speed, accelerator releasing speed, road gradient, vehicle weight, relative physical relation with a forward obstacle, road surface friction coefficient and the like immediately before the accelerator is released and regenerative braking is controlled based on the target braking force. 
       CITATION LIST 
     Patent Literature 
       [0008]    PTL1: JP 9-037407 A 
       SUMMARY OF INVENTION 
     Technical Problem 
       [0009]    However, the braking force of a vehicle changes depending on the road surface friction coefficient and road gradient on a traveling route, the vehicle weight and the like. Thus, it is difficult to determine an appropriate regenerative braking force from conditions immediately before the accelerator is released. If, for example, the regenerative braking force is too strong, the vehicle is stopped unnecessarily by too much deceleration and the driver feels uncomfortable. In addition, the driver operates the accelerator to try to accelerate the vehicle, leading to fuel inefficiency. If the regenerative braking force is weak and deceleration of the vehicle is small, the driver operates the brake pedal to try to decelerate the vehicle. In a vehicle in which a friction brake is applied by being linked to a brake pedal, the braking force by the friction brake increases with an operation amount of the brake pedal, leading to increasing energy losses and fuel inefficiency. Therefore, it is desirable to increase the regenerative braking force without decelerating too much and after the accelerator is released, to continue to update the regenerative braking force based on external world information acquired by an external recognition sensor while the brake pedal is operated to improve fuel efficiency. However, if the regenerative braking force changes while the driver operates the brake pedal, a problem of the brake operation by the driver being hindered by changes of the regenerative braking force arises. 
       Solution to Problem 
       [0010]    A drive control device of a moving body according to the present invention is a drive control device of a moving body that updates a regenerative pattern of a driving motor of the moving body including a brake that generates a braking force by being linked to an operation amount of a brake pedal, the drive control device including an external world information acquisition unit that acquires external world information and a brake detector that detects ON/OFF of the brake, wherein when the brake detector detects ON, the regenerative pattern is changed based on the external world information acquired by the external world information acquisition unit such that a braking distance only decreases. 
       Advantageous Effects of Invention 
       [0011]    According to the present invention, the regeneration amount can be increased without hindering a driver&#39;s brake operation and causing too much deceleration. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0012]      FIG. 1  is a diagram showing an outline configuration of a drive control device according to a first embodiment. 
           [0013]      FIG. 2  is a block diagram of a control operation unit  8  according to the first embodiment. 
           [0014]      FIG. 3  is a block diagram of a target deceleration operation unit  101  according to the first embodiment. 
           [0015]      FIG. 4  is a block diagram of a target deceleration torque operation unit  103  according to the first embodiment. 
           [0016]      FIG. 5  is a diagram illustrating an operation example of the drive device when the present invention in the first embodiment is not used. 
           [0017]      FIG. 6  is a diagram illustrating an operation example of the drive device according to the first embodiment. 
           [0018]      FIG. 7  is a diagram illustrating an operation example of the drive device according to the first embodiment. 
           [0019]      FIG. 8  is an image diagram when vehicles stop in front at a red signal in the first embodiment. 
           [0020]      FIG. 9  is an image diagram when entering a red signal while there is no vehicle in front in the first embodiment. 
           [0021]      FIG. 10  is a diagram showing a driving force when the accelerator is released in a second embodiment. 
           [0022]      FIG. 11  is a diagram showing a block diagram of the target deceleration operation unit  101  according to the second embodiment. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0023]    Hereinafter, the embodiments to carry out the present invention will be described with reference to the drawings. In the embodiments described below, the present invention is described by taking a case when applied to a drive system of an electric vehicle in which a motor is the only power source of the vehicle as an example, but the present invention can also be applied to the control device of motor vehicles of rolling stock, construction vehicles and the like and motor vehicles in which an engine as an internal combustion engine and a motor are used as power sources of the vehicle, for example, hybrid vehicles (passenger cars), freight vehicles such as hybrid trucks, and buses such as hybrid buses. 
       First Embodiment 
       [0024]      FIG. 1  is a diagram showing the configuration of a drive control device of an electric vehicle in the first embodiment. Broken line arrows in  FIG. 1  show the flow of signals. The vehicle includes a battery  1  as an energy source of the vehicle, a motor  2  to electrically drive the vehicle, an inverter power supply  3  to make a power conversion between the battery  1  and the motor  2 , and the control operation unit  8  to control the inverter power supply  3 , a braking device  7  and the like. 
         [0025]    The inverter power supply  3  converts a direct current supplied from the battery  1  into a three-phase alternating current by pulse width modulation (PWM) and supplies the alternating current to the motor  2 . The motor  2  converts electric energy supplied as a three-phase alternating current from the inverter power supply  3  into kinetic energy. Power generated by the motor  2  as kinetic energy is transmitted to a reduction gear  4  and decelerated by a deceleration mechanism inside the reduction gear  4  and then transmitted left and right driving wheels  6  via a differential mechanism  5  to become a driving force to drive the vehicle. In addition, kinetic energy of the vehicle is converted into electric energy by causing the motor  2  to perform a regenerative operation so that the electric energy can be recovered to the battery  1 . The recovered electric energy can be converted into kinetic energy again and thus, fuel efficiency of the vehicle can be improved by causing the motor  2  to perform a regenerative operation. 
         [0026]    The braking device  7  that generates a braking force of the vehicle in accordance with an operation amount of a brake pedal  13  is provided near the driving wheel  6 . The braking device  7  includes a hydraulic booster and a frictional force is generated by pressing the driving wheel  6  by a hydraulic operating force generated by the hydraulic booster. Accordingly, kinetic energy is converted into thermal energy to brake the vehicle. 
         [0027]    In  FIG. 1 , the control operation unit  8  is comprised of CPU, a memory and the like and controls the motor  2  by executing a control program. The control operation unit  8  can change torque generated by the motor  2  and regenerated power charged in the battery  1  by sending a command to the inverter power supply  3  to change the magnitude of current passed to the motor  2  or the frequency of an alternating current. 
         [0028]    As shown in  FIG. 1 , a vehicle speed sensor  9  to detect the vehicle speed, an accelerator sensor  10  to detect an accelerator pedal opening (operation amount of the accelerator pedal), a brake switch  11  to detect ON/OFF of the brake pedal  13 , and an external recognition sensor  12  to acquire external world information are connected to the control operation unit  8 . The external recognition sensor  12  can detect the type of a deceleration object of the vehicle, the relative distance, and the relative speed as external world information. 
         [0029]    To detect a braking force generated by the braking device  7 , an expensive sensor such as a stepping force sensor of the brake pedal is needed. In the embodiments of the present invention, a sensor to detect a braking force generated by the braking device  7  or the like is not provided to reduce the system cost. 
         [0030]    Next, the configuration of the control operation unit  8  will be described using  FIG. 2 . A target driving torque operation unit  100  calculates the target torque of the motor  2 , that is, the target driving torque when there is no intervention of deceleration control after a vehicle speed signal is input from the vehicle speed sensor  9  and an accelerator opening signal is input from the accelerator sensor  10 . The accelerator opening of the accelerator pedal is proportional to an output request and thus, the accelerator opening is converted into an output request and divided by the vehicle speed to calculate a driving force request of the vehicle, that is, the target driving torque of the motor  2 . 
         [0031]    A target behavior operation unit  99  calculates a target distance  198  and a target speed  199  at the target distance  198  after a vehicle speed signal is input from the vehicle speed sensor  9  and the type of a deceleration object, the relative distance, and the relative speed are input from the external recognition sensor  12  as external world information. Correspondences from the relative distance, relative speed, and vehicle speed of the deceleration object to the target distance  198  and the target speed  199  are stored in a memory provided in the control operation unit  8  as a numerical map for each type of the deceleration object. 
         [0032]    The target deceleration operation unit  101  calculates the intended deceleration, that is, target deceleration  201  when there is an intervention of deceleration control after a brake switch signal is input from the brake switch  11 , the target distance  198  and the target speed  199  are input from the target behavior operation unit  99 , and a vehicle speed signal is input from the vehicle speed sensor  9 . 
         [0033]    A deceleration operation unit  102  calculates deceleration  202  of the vehicle by a difference calculation after a vehicle speed signal is input from the vehicle speed sensor  9 . 
         [0034]    The target deceleration torque operation unit  103  calculates target deceleration torque  203  to match the deceleration  202  calculated by the deceleration operation unit  102  to the target deceleration  201  calculated by the target deceleration operation unit  101  when there is an intervention of deceleration control after a vehicle speed signal is input from the vehicle speed sensor  9 , a brake switch signal is input from the brake switch  11 , the target deceleration  201  is input from the target deceleration operation unit, and the deceleration  202  is input from the deceleration operation unit  102 . 
         [0035]    A control intervention arbitration unit  104  determines whether to allow an intervention of deceleration control after an accelerator opening signal is input from the accelerator sensor  10 , target driving torque  200  is input from the target driving torque operation unit  100 , and the target deceleration torque  203  is input from the target deceleration torque operation unit  103 . If the accelerator opening signal is equal to a predetermined value or less, the control intervention arbitration unit  104  determines to allow an intervention and sends the target deceleration torque  203  to the inverter power supply  3  as target torque  204 . If the accelerator opening signal is equal to a predetermined value or more, the control intervention arbitration unit  104  determines to not allow an intervention and sends the target driving torque  200  to the inverter power supply  3  as the target torque  204 . 
         [0036]    The target torque  204  is sent to the inverter power supply  3  and torque control is performed so that the torque is generated. 
         [0037]    Next, the target deceleration operation unit  101  will be described using  FIG. 3 . 
         [0038]    In the target deceleration operation unit  101 , a target deceleration calculation  110  determines a target deceleration base value  210  (Gb) from the target distance  198  (Lr), the target speed  199  (Vr), and the vehicle speed signal (V) input from the target behavior operation unit  99  as Gb=(V 2 −Vr 2 )/(2Lr). The target deceleration base value  210  (Gb) is deceleration to reach the target speed  199  (Vr) from the vehicle speed signal (V) after traveling the target distance  198  (Lr). Therefore, a braking distance of the vehicle decreases as the target deceleration base value  210  (Gb) increases. Here, the braking distance is a travel distance needed for the vehicle speed to be decelerated to a predetermined value. 
         [0039]    A last value hold  111  calculates a target deceleration last value  211  as the last value of the target deceleration  201 . 
         [0040]    A select-high  112  selects the larger of the target deceleration base value  210  (Gb) input from the target deceleration calculation  110  and the target deceleration last value  211  input from the last value hold  111  to calculate a target deceleration change direction limiting value  212 . Thus, the braking distance by the target deceleration change direction limiting value  212  is always shorter than the braking distance when the last value of the target deceleration  201  is used. 
         [0041]    A selector  113  outputs the target deceleration base value  210  as the target deceleration  201  when a brake switch signal is OFF and the target deceleration change direction limiting value  212  as the target deceleration  201  when the brake switch signal is ON after the brake switch signal is input from the brake switch  11 , the target deceleration base value  210  is input from the target deceleration calculation  110 , and the target deceleration change direction limiting value  212  is input from the select-high  112 . When the brake switch is ON, the target deceleration  201  changes such that the braking distance only decreases. 
         [0042]    As described above, the target deceleration  201  changes such that the braking distance only decreases when the brake switch is ON and thus, changes of the target deceleration  201  do not hinder the driver&#39;s brake operation. 
         [0043]    Next, the target deceleration torque operation unit  103  will be described using  FIG. 4 . 
         [0044]    In the target deceleration torque operation unit  103 , a torque converter  120  calculates a target deceleration torque base value  220  (Tb) from the vehicle speed signal (V) input from the vehicle speed sensor  9  and the target deceleration  201  (Gr) input from the target deceleration operation unit  101  as Tb={M·Gr+M·g·μ+(ρ·Cd·A·V 2 )/2}·R/η. where M is the estimated value of the vehicle weight, g is the gravitational acceleration, μ is the estimated value of the rolling resistance coefficient, ρ is the air density, Cd is the estimated value of a Cd value, A is the frontal projected area, R is the radius of a vehicle wheel, and r is the reduction ratio from a motor shaft to an axle. 
         [0045]    A difference between the target deceleration  201  input from the target deceleration operation unit  101  and the deceleration  202  input from the deceleration operation unit  102  is found at  1000  to calculate a deceleration deviation  221 . 
         [0046]    A proportion operation  121  calculates a proportion correction value  222  by multiplying the deceleration deviation  221  by a constant when a brake switch signal input from the brake switch  11  is OFF. When the brake switch signal is ON, the last value of the proportion correction value  222  is output as the proportion correction value  222 . 
         [0047]    An integral operation  122  calculates an integral correction value  223  by multiplying an integrated value of the deceleration deviation  221  by a constant when a brake switch signal input from the brake switch  11  is OFF. When the brake switch is ON, the last value of the integral correction value  223  is output as the integral correction value  223 . At  1001 , the sum of the target deceleration torque base value  220 , the proportion correction value  222 , and the integral correction value  223  is calculated to set the sum as the target deceleration torque  203 . 
         [0048]    By adding the proportion correction value  222  and the integral correction value  223  to the target deceleration torque base value  220  as described above, the deceleration  202  of the vehicle can be matched to the target deceleration  201  so that the speed at the target distance  198  is the target speed  199 . Accordingly, fuel efficiency of the vehicle can be improved by increasing the regeneration amount without decelerating too much. When the brake switch is ON as described above, the last values are used as the proportion correction value  222  and the integral correction value  223  and thus, the braking distance decreases for the target deceleration torque  203 . Therefore, changes of the target deceleration torque  203  do not hinder the driver&#39;s brake operation. 
         [0049]    Effects of the present embodiment will be described using  FIGS. 5, 6, and 7 . 
         [0050]      FIG. 5  is a diagram illustrating an operation when the present embodiment is not used, that is, when the brake is ON, the regenerative pattern is not changed such that the braking distance only decreases. When the driver releases the accelerator at time t 1 , the drive device increases the braking force using regeneration up to F 1  so that the speed at the target distance  198  is decelerated to the target speed  199  based on external world information. When the driver steps on the brake to increase deceleration at time t 2 , a braking force by the friction brake is generated. However, the drive device determines that the deceleration by the friction brake is too much and decreases the braking force using regeneration so that the speed at the target distance  198  is the target speed  199 . As a result, in the time between time t 2  and time t 3 , the braking force does not change in response to the driver&#39;s brake operation so that the drive device hinders the driver&#39;s brake operation. Therefore, a stop position L 1  at time t 4  exceeds the driver&#39;s target stop position. 
         [0051]      FIG. 6  is a diagram illustrating an operation when the present embodiment is used, that is, when the brake is ON, the regenerative pattern is changed such that the braking distance only decreases. When the driver releases the accelerator at time t 5 , the drive device according to the present embodiment increases the braking force using regeneration up to F 2  such that the speed at the target distance  198  is decelerated to the target speed  199  based on external world information. Accordingly, fuel efficiency can be improved. When the driver steps on the brake to increase deceleration at time t 6 , a braking force by the friction brake is generated. At this point, it is necessary to change the regenerative pattern such that the braking distance increases to match the speed at the target distance  198  to the target speed  199 , but the brake is ON and the drive device according to the present embodiment does not change the regenerative pattern. Thus, in the time between time t 6  and time t 7 , the braking force can be changed by reflecting the driver&#39;s brake operation. Accordingly, the stop position at time t 7  can be selected as the driver&#39;s target stop position. 
         [0052]      FIG. 7  is a diagram illustrating an operation when the brake is ON and the regenerative pattern is changed such that the braking distance only decreases and also from time t 10  onward, the target distance  198  and the target speed  199  approach the driver&#39;s intention. When the driver releases the accelerator at time t 9 , the drive device according to the present embodiment increases the braking force using regeneration up to F 3  such that the speed at the target distance  198  is decelerated to the target speed  199  based on external world information. Accordingly, fuel efficiency can be improved. When the driver steps on the brake to increase deceleration at time t 9 , a braking force by the friction brake is generated. At this point, it is necessary to change the regenerative pattern such that the braking distance increases to match the speed at the target distance  198  to the target speed  199 , but the brake is ON and the drive device according to the present embodiment does not change the regenerative pattern. Thus, in the time between time t 9  and time t 10 , the braking force can be changed by reflecting the driver&#39;s brake operation. If the target distance  198  and the target speed  199  change as shown in  FIG. 7  from time t 10  to time t 11 , the drive device according to the present embodiment changes the regenerative pattern to match the speed at the target distance  198  to the target speed  199 . While the brake is ON from time t 10  to time t 11 , the regenerative pattern needs to be changed such that the braking distance decreases to match the speed at the target distance  198  to the target speed  199  and therefore, the braking force using regeneration is changed up to F 4 . The driver always fine-tunes the brake operation so as to stop the vehicle in the driver&#39;s target stop position. The target distance  198  and the target speed  199  change from time t 10  to time t 11  and thus, the driver eases up on the brake operation to stop the vehicle in the target stop position. As a result, the braking force by the friction brake is decreased and the braking force using regeneration can be increased and therefore, fuel efficiency can further be improved. Also, the stop position at time t 12  can be selected as the driver&#39;s target stop position. 
         [0053]    The external recognition sensor  12  may be any sensor capable of detecting the distance to an object in front of the local vehicle such as a laser radar, a radar, and a stereo camera and in the present embodiment, a stereo camera is used as the external recognition sensor  12 . 
         [0054]    The stereo camera used as the external recognition sensor  12  in the present embodiment can detect a preceding vehicle as a deceleration object. Thus, when decelerated with respect to the preceding vehicle, fuel efficiency can be improved by increasing the regeneration amount. 
         [0055]    In a situation shown in  FIG. 8  in which a signal  701  is red and vehicles  702 ,  703  stop in front, a laser radar or a radar cannot determine whether the vehicles  702 ,  703  that stop or a wall that happens to appear in front until the distance to a local vehicle  704  becomes short and so cannot determine to increase regeneration sufficiently in advance. 
         [0056]    However, a stereo camera can determine that an object present before is a vehicle based on the color and shape of a vehicle and the distance to the recognized object can be detected from the time when the object is far away so that the regeneration amount can be increased. 
         [0057]    The stereo camera used as the external recognition sensor  12  in the present embodiment can detect a curve on a traveling route as a deceleration object. Thus, when decelerated with respect to a curve on the traveling route, fuel efficiency can be improved by increasing the regeneration amount. 
         [0058]    The stereo camera used as the external recognition sensor  12  in the present embodiment can detect a width decreased portion on the traveling route as a deceleration object. Thus, when decelerated with respect to a width decreased portion on the traveling route, fuel efficiency can be improved by increasing the regeneration amount. 
         [0059]    In addition, using a map of a navigation system jointly as the external recognition sensor  12  can be considered. By using a map of a navigation system jointly, the external recognition sensor  12  in the present embodiment can detect a red signal stop line on the traveling route. Thus, when decelerated with respect to a red signal stop line on the traveling route, fuel efficiency can be improved by increasing the regeneration amount. 
         [0060]    When, as shown in  FIG. 9 , there is no object in front of a local vehicle  705 , the regeneration amount cannot be increased by using a laser radar or a radar. In such a case, the regeneration amount can be increased even in a situation as shown in  FIG. 9  by detecting a red signal using a stereo camera and calculating the distance to a stop line from a map. 
         [0061]    By using a map of a navigation system jointly, the external recognition sensor  12  in the present embodiment can detect a tollgate on the traveling route. Thus, when decelerated with respect to a tollgate on the traveling route, fuel efficiency can be improved by increasing the regeneration amount. 
         [0062]    By using a map of a navigation system jointly, the external recognition sensor  12  in the present embodiment can detect a downhill grade on the traveling route. Thus, when decelerated with respect to a downhill grade on the traveling route, fuel efficiency can be improved by increasing the regeneration amount. 
       Second Embodiment 
       [0063]      FIG. 10  is a diagram showing a driving force when the accelerator is released in the second embodiment of the present invention and  FIG. 11  is a diagram showing a block diagram of the target deceleration operation unit  101  in the second embodiment of the present invention. The second embodiment is a modification of a portion of the configuration (configuration of the target driving torque operation unit  100  and the target deceleration operation unit  101 ) of the first embodiment described above. The same reference signs are attached to elements similar to those shown in  FIGS. 1 and 2  and the description below focuses on differences. 
         [0064]    The target driving torque operation unit  100  calculates the target torque of the motor  2 , that is, the target driving torque when there is no intervention of deceleration control after a vehicle speed signal is input from the vehicle speed sensor  9  and an accelerator opening signal is input from the accelerator sensor  10 . The accelerator opening of the accelerator pedal is proportional to an output request and thus, the accelerator opening is converted into an output request, divided by the vehicle speed, and a basic driving force at accelerator release  403  being added to calculate a driving force request of the vehicle, that is, the target driving torque of the motor  2 . 
         [0065]      FIG. 10  is a diagram showing the driving force when the accelerator is released. When the vehicle speed is equal to a predetermined value or less, the driving force is a positive value corresponding to a creep. When the vehicle speed is equal to the predetermined value or more, the driving force is negative. 
         [0066]    In the target deceleration operation unit  101  according to the second embodiment, a target gain calculation  310  determines a target gain base value  410  from the target distance  198  (Lr), the target speed  199  (Vr), and the vehicle speed signal (V) input from the target behavior operation unit  99 . The target gain base value  410  is multiplied by a basic driving force at accelerator release  402  to be used for calculating the driving force at accelerator release  403 . The target gain base value  410  is a value to achieve the target speed  199  (Vr) after traveling the target distance  198  (Lr) if decelerated by the driving force at accelerator release  403  when the accelerator is released. Therefore, the braking distance of the vehicle decreases as the target gain base value  410  increases. Here, the braking distance is a travel distance needed for the vehicle speed to be decelerated to a predetermined value. 
         [0067]    The last value hold  111  calculates a target gain last value  411  as the last value of a target gain  401  (K). 
         [0068]    The select-high  112  selects the larger of the target gain base value  410  input from the target gain calculation  310  and the target gain last value  411  input from the last value hold  111  to calculate a target gain change direction limiting value  412 . Thus, the braking distance by the target gain change direction limiting value  412  is always shorter than the braking distance when the last value of the target gain  401  (K) is used. 
         [0069]    The selector  113  outputs the target gain base value  410  as the target gain  401  (K) when a brake switch signal is OFF and the target gain change direction limiting value  412  as the target gain  401  (K) when the brake switch signal is ON after the brake switch signal is input from the brake switch  11 , the target gain base value  410  is input from the target gain calculation  310 , and the target gain change direction limiting value  412  is input from the select-high  112 . When the brake switch is ON, the target gain  401  (K) changes such that the braking distance only decreases. 
         [0070]    As described above, the target deceleration  201  changes such that the braking distance only decreases when the brake switch is ON and thus, changes of the target gain  401  (K) do not hinder the driver&#39;s brake operation. 
         [0071]    A basic driving force calculation at accelerator release  311  calculates the basic driving force at accelerator release  402  by inputting a vehicle speed signal. The basic driving force at accelerator release  402  is, as shown in  FIG. 10 , a positive value corresponding to a creep when the vehicle speed is equal to a predetermined value or less. When the vehicle speed is equal to the predetermined value or more, the driving force is negative. 
         [0072]    An integrating unit  312  calculates the driving force at accelerator release  403  by integrating the basic driving force at accelerator release  402  and the target gain  401  (K). 
         [0073]    A deceleration conversion  313  calculates the target deceleration  201  (Gr) from the driving force at accelerator release  403  (Fc) as Gr={Fc−M˜g·μ−(ρ·Cd·A·V 2 )/2}/M. 
         [0074]    In the target deceleration operation unit  101  according to the second embodiment, the driving force while regeneration is increased, that is, the driving force at accelerator release  403  is made K times the basic driving force at accelerator release  402  and thus, the creep can continuously be linked when the vehicle is decelerated. Also when regeneration is increased, the deceleration pattern is close to normal deceleration by an engine brake and thus, an uncomfortable feeling of the driver can be reduced and the driver&#39;s brake operation can be made easier. 
       REFERENCE SIGNS LIST 
       [0000]    
       
           1  battery 
           2  motor 
           3  inverter power supply 
           4  reduction gear 
           5  differential mechanism 
           6  driving wheel 
           7  braking device 
           8  control operation unit 
           9  vehicle speed sensor 
           10  accelerator sensor 
           11  brake switch 
           12  external recognition sensor 
           13  brake pedal 
           99  target behavior operation unit 
           100  target driving torque operation unit 
           101  target deceleration operation unit 
           102  deceleration operation unit 
           103  target deceleration torque operation unit 
           104  control intervention arbitration unit 
           110  target deceleration calculation 
           111  last value hold 
           112  select-high 
           113  selector 
           120  torque converter 
           121  proportion operation 
           122  integral operation 
           198  target distance 
           199  target speed 
           200  target torque 
           201  target deceleration 
           202  deceleration 
           203  target deceleration torque 
           204  target torque 
           210  target deceleration base value 
           212  target deceleration change direction limiting value 
           220  target deceleration torque base value 
           221  deceleration deviation 
           222  proportion correction value 
           223  integral correction value 
           310  target gain calculation 
           311  basic driving force calculation at accelerator release 
           312  integrating unit 
           313  deceleration conversion 
           401  target gain 
           402  basic driving force at accelerator release 
           403  driving force at accelerator release 
           410  target gain base value 
           411  target gain last value 
           412  target gain change direction limiting value 
           701  signal 
           702 ,  703  vehicle 
           704  local vehicle 
           705  local vehicle