JP2006129584A - Traction controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a traction controller which can prevent the initial slippage at the time of start. <P>SOLUTION: The traction controller 1 is equipped with an electric motor 40 which drives the driving wheels 10FL and 10FR of a vehicle HV at the time of start, a road frictional coefficient estimator 71a which estimates the frictional coefficient μ of a road, a starting torque computer 71b which sets the drive torque limit value Tl at the time of start, based on the road frictional coefficient μ, a driving torque detector 73a which detects the drive torque T of the driving wheels 10FL and 10FR, and a motor ECU 73 which limits the output rise of the electric motor 40 in case that the drive torque T gets over the drive torque limit value Tl, at the time of start of a vehicle. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a traction control device for a vehicle that prevents slipping of drive wheels.

2. Description of the Related Art Conventionally, a traction control technique is known in which when a drive wheel of a vehicle slips, an engine output or a motor output is adjusted to suppress the slip amount of the drive wheel to a predetermined value or less. As one of such traction control techniques, a technique for correcting slip by controlling the output torque of a driving motor for an electric vehicle when slippage of a drive wheel is detected is described in Patent Document 1 below. Yes.
JP-A-8-182119

  The conventional traction control technology suppresses the slip that has already occurred by adjusting the output of the driving motor etc. when the slip of the drive wheel is detected, thus preventing the initial slip at the start Can not do it. In particular, when a magnetic pickup type wheel speed sensor is used, since the low vehicle speed cannot be detected, the initial slip becomes large. For example, in a start on a snowy uphill road, once the wheel is slipped, the snow may be compressed and the road surface friction coefficient may be reduced, thereby making it difficult to start. Therefore, a technique capable of preventing initial slip at the time of starting has been desired.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a traction control device that can prevent an initial slip at the time of starting.

  A traction control device according to the present invention includes a driving force source that drives a driving wheel of a vehicle, a road surface friction coefficient estimating unit that estimates a friction coefficient of a road surface, and a road surface estimated by a road surface friction coefficient estimating unit while the vehicle is traveling. Start torque calculation means for setting a drive torque limit value at the start based on the friction coefficient, drive torque detection means for detecting the drive torque of the drive wheels, and drive torque detected by the drive torque detection means at the time of vehicle start Is provided with control means for suppressing an increase in the output of the driving force source when the driving torque limit value is not less than the driving torque limit value set during the previous traveling.

  According to the traction control device of the present invention, when the vehicle starts, when the driving torque of the driving wheels is equal to or higher than the driving torque limit value, that is, the driving torque that can be transmitted to the road surface obtained from the latest estimated road surface friction coefficient, the driving force Since an increase in the output of the power source is suppressed, an initial slip at the start can be prevented.

  Further, the traction control device according to the present invention includes a driving force source for driving the driving wheels of the vehicle, a slip detecting means for detecting slip of the driving wheels, an acceleration detecting means for detecting the acceleration of the vehicle, A starting torque calculating means for setting a driving torque limit value at the start based on the acceleration detected by the acceleration detecting means when the slip detecting means detects the slip of the driving wheel, and detecting the driving torque of the driving wheel Driving torque detecting means that controls the increase in the output of the driving force source when the driving torque detected by the driving torque detecting means is equal to or greater than the driving torque limit value set during the previous travel. Means.

  According to the traction control device of the present invention, when the vehicle starts, when the driving torque of the driving wheels is equal to or greater than the driving torque limit value, that is, the driving torque that can be transmitted to the road surface obtained from the vehicle acceleration at the time of slipping, Therefore, the initial slip at the time of starting can be prevented.

  In addition, the traction control device according to the present invention includes required drive torque calculation means for calculating the required drive torque requested by the driver based on the operation amount of the accelerator pedal, and the control means drives the drive torque of the drive wheels. It is preferable to control the output of the driving force source so as to gradually approach the required driving torque from the torque limit value.

  In this case, the driving torque of the driving wheel is gradually increased from the driving torque limit value to the driving torque requested by the driver while suppressing a sudden driving torque change, so that the driving wheel starts so as not to slip. It is possible to suppress the sudden increase in the slip amount during acceleration. Therefore, the vehicle stability at the time of starting acceleration can be improved.

  Further, in the traction control device according to the present invention, when the starting torque calculating means detects that the driving torque detected by the driving torque detecting means when starting the vehicle is equal to or greater than the driving torque limit value, a predetermined initial value is set as the driving torque limit value. Is preferably set.

  In this case, as a predetermined initial value, for example, by setting a driving torque value corresponding to the maximum road surface friction coefficient, even if the friction coefficient of the traveling road surface increases during traveling, the driving torque is insufficient when the vehicle starts next time. Can be prevented. When the road friction coefficient estimated during traveling is smaller than a predetermined initial value, the drive torque based on the estimated road friction coefficient is reset as the drive torque limit value at the time of start.

  In the traction control device according to the present invention, the driving force source is preferably an electric motor.

  When the driving force source is an electric motor, the output torque control delay is small and the output torque can be estimated accurately, so that the driving torque of the driving wheels can be controlled appropriately.

  According to the present invention, when the vehicle starts, when the driving torque of the driving wheels exceeds the driving torque limit value obtained based on the road surface friction coefficient, the increase in the output of the driving force source is suppressed. It becomes possible to prevent the initial slip at the time.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the figure, the same reference numerals are used for the same or corresponding parts.

  First, the main configuration of a hybrid vehicle HV equipped with the traction control device 1 according to the present embodiment will be described with reference to FIG. FIG. 1 is a block diagram showing a main configuration of a hybrid vehicle HV equipped with a traction control device 1. The hybrid vehicle HV includes a power plant 20 that outputs driving torque that drives the left front wheel 10FL, which is a driving wheel, a right front wheel 10FR, a left rear wheel 10RL which is a driven wheel, a right rear wheel 10RR, and left and right driving wheels 10FL, 10FR, And an electronic control unit 70 that controls the driving torque of the driving wheels 10FL and 10FR by comprehensively controlling the operation of the power plant 20.

  The power plant 20 includes an engine 21 that is an internal combustion engine and an electric motor 40. Further, the hybrid vehicle HV changes the rotational speed of the left and right drive wheels 10FL, 10FR when the vehicle turns and also drives the drive wheels 10FL, 10FR evenly while converting and outputting the drive torque from the engine 21. The differential 30 that transmits force, the transfer 32 that transmits drive torque from the engine 21 and the electric motor 40 to the differential 30, the propeller shaft 34 that transmits drive torque from the electric motor 40 to the transfer 32, and the differential 30 are output. Drive shafts 36L and 36R for transmitting drive torque to drive wheels 10FL and 10FR are provided.

  In the engine 21, the sucked intake air is sucked into each cylinder 22 formed in the engine 21 via the intake manifold 24. Each cylinder 22 is provided with an injector 23 for injecting fuel, and high pressure fuel is guided to each injector 23. A drive torque is generated by the combustion of the mixed gas of intake air and fuel in each cylinder 22. The exhaust gas after combustion is exhausted to the exhaust manifold 25.

  The electric motor 40 is an AC synchronous motor and is driven by AC power output from the inverter 50. The electric motor 40 can also generate power (regenerative power generation) by using the rotation of the drive wheels 10FL and 10FR.

  The inverter 50 converts the electric power stored in the high voltage battery 60 from direct current to alternating current and supplies it to the electric motor 40, and also converts the electric power regenerated by the electric motor 40 from alternating current to direct current to convert the electric power to the high voltage battery 60. To store.

  The drive torque output from the engine 21 is transmitted to the transfer 32 via the transmission 28. On the other hand, the drive torque output from the electric motor 40 is transmitted to the transfer 32 via the propeller shaft 34. Thus, the engine 21 and the electric motor 40 are connected by the transfer 32, and the drive torque of the engine 21 and the electric motor 40 input to the transfer 32 is transmitted to the differential 30 in parallel, and further, the drive shaft 36L, It is transmitted to the left and right drive wheels 10FL, 10FR via 36R.

  The hybrid vehicle HV is started by the electric motor 40. During acceleration, the output of the electric motor 40 is added to the output of the engine 21 and applied to the drive wheels 10FL and 10FR. Further, during normal traveling, the engine 21 and the electric motor 40 are selectively used depending on the traveling state and the like.

  The electronic control unit 70 that controls the power plant 20 is set by an electronic control unit (hereinafter referred to as “TRC ECU”) 71 that sets the target drive torque Tt of the drive wheels 10FL and 10FR, the driving state of the vehicle HV, and the TRC ECU 71. The hybrid ECU (hereinafter referred to as “HV ECU”) that sets the target outputs of the engine 21 and the electric motor 40 according to the target drive torque Tt and controls the operation of the engine 21 based on the set target engine output Te. 72 and a motor ECU 73 that drives and controls the electric motor 40 based on a target motor output Tm set by the HV ECU 72.

  Each of the TRC ECU 71, the HV ECU 72, and the motor ECU 73 includes a microprocessor that performs calculations therein, a ROM that stores programs for causing the microprocessor to execute each process, a RAM that stores various data such as calculation results, and a 12V It has a backup RAM or the like whose stored contents are held by a battery. Further, each of the TRC ECU 71, the HV ECU 72, and the motor ECU 73 is connected by a communication line 76 such as a CAN (Controller Area Network), and is configured to be able to exchange data with each other.

  The TRC ECU 71 includes a longitudinal acceleration sensor 77 for detecting longitudinal acceleration Gx and lateral acceleration Gy of the vehicle HV, and wheel speed sensors 78FL, 78FR for detecting wheel speeds of the driving wheels 10FL, 10FR and driven wheels 10RL, 10RR, respectively. 78RL, 78RR, etc. are connected.

  Further, inside the TRC ECU 71, a road surface friction coefficient estimating unit 71a that estimates the road surface friction coefficient μ from the longitudinal acceleration Gx and the left and right acceleration Gy of the vehicle HV, and a road surface friction coefficient μ estimated by the road surface friction coefficient estimating unit 71a is started. A starting torque calculating unit 71b for calculating the driving torque limit value Tl for the hour is constructed. That is, the TRC ECU 71 functions as a road surface friction coefficient estimating unit and a starting torque calculating unit.

  The TRC ECU 71 sets the target of the drive wheels 10FL and 10FR based on the driver's requested drive torque Td input from the HV ECU 72 via the communication line 76 and the drive torque limit value Tl calculated by the start torque calculation unit 71b. A drive torque Tt is set. Specifically, standby traction control that sets the target drive torque Tt so that the output increase of the electric motor 40 is suppressed when the drive torque of the drive wheels 10FL and 10FR is equal to or greater than the drive torque limit value Tl at the time of start. Do. At this time, the set target drive torque Tt is output to the HV ECU 72 via the communication line 76.

  Further, the TRC ECU 71 calculates the slip ratio of the drive wheels 10FL and 10FR according to the difference between the driven wheel speed and the drive wheel speed, and the braking force, the motor output, and the engine so that the slip ratio matches the target slip ratio. So-called basic traction control (hereinafter referred to as “basic traction control”) for adjusting the output is performed.

  Here, basic traction control will be described. The TRC ECU 71 calculates an average value of the wheel speeds of the driven wheels 10RL and 10RR detected by the wheel speed sensors 78RL and 78RR, and sets the calculation result as an estimated vehicle speed. Then, the slip ratios of the drive wheels 10FL and 10FR are calculated according to the difference between the estimated vehicle body speed and the wheel speeds of the drive wheels 10FL and 10FR.

  The TRC ECU 71 adjusts the braking force applied to the driving wheels 10FL, 10FR and / or the driving torque transmitted to the driving wheels 10FL, 10FR based on the calculated slip ratio, thereby driving the driving wheels. The slip amount of 10FL and 10FR is controlled to an appropriate value.

  The HV ECU 72 is connected to an accelerator position sensor 79 that detects the accelerator opening, a shift position sensor that detects the shift position of the automatic transmission 28, and the like.

  Further, in the HV ECU 72, a required drive torque calculation unit 72a that calculates a required drive torque Td requested by the driver based on an accelerator opening, a shift position, and the like is constructed. That is, the HV ECU 72 functions as a required drive torque calculation unit. The calculated required drive torque Td is output to the TRC ECU 71 via the communication line 76.

  The HV ECU 72 sets target outputs of the engine 21 and the electric motor 40 according to the driving state of the vehicle HV and the target drive torque Tt input from the TRC ECU 71. Then, based on the set target engine output Te, the operation of the engine 21 is controlled by adjusting the intake air amount, the fuel injection amount, the ignition timing, and the like. On the other hand, the set target motor output Tm is output to the motor ECU 73 via the communication line 76.

  The motor ECU 73 is connected to a resolver 41 that detects the rotational speeds of the inner rotor and the outer rotor of the electric motor 40, a current sensor 51 that detects a phase current flowing through the three-phase wire 45, and the like.

  In addition, a drive torque detection unit 73a for obtaining the drive torque T of the drive wheels 10FL and 10FR based on the drive torque of the electric motor 40 calculated from the detected phase current is built in the motor ECU 73. The motor ECU 73 drives the electric motor 40 by performing switching control of the inverter 50 based on the input signal from the sensor and the target motor output Tm set by the HV ECU 72. Here, since the hybrid vehicle HV is driven only by the electric motor 40 when the vehicle starts, in this embodiment, the motor ECU 73 functions as drive torque detection means and control means.

  Next, the operation of the traction control device 1 will be described with reference to FIG. Here, FIG. 2 is a flowchart showing a processing procedure of standby traction control by the traction control device 1. These processes are repeatedly executed at a predetermined timing from when the power supply of the TRC ECU 71, the HV ECU 72, and the motor ECU 73 is turned on until it is turned off.

  In step S100, a determination is made as to whether both basic traction control and standby traction control are stopped. Here, when both the basic traction control and the standby traction control are stopped, the process proceeds to step S102. On the other hand, when either one or both of the basic traction control and the standby traction control are being executed, the process proceeds to step S110.

  In step S102, it is determined whether or not the speed Vx of the vehicle HV is equal to or higher than the predetermined value Va and lower than the predetermined value Vb. Here, when the speed Vx of the vehicle HV is equal to or higher than the predetermined value Va and lower than the predetermined value Vb, the process proceeds to step S104. On the other hand, when the speed Vx of the vehicle HV is lower than the predetermined value Va or equal to or higher than the predetermined value Vb, the process proceeds to step S110 without executing the standby traction control. In order to start standby traction control in a low speed region at the time of departure, for example, the predetermined value Va is set to 0.5 km / h, and the predetermined value Vb is set to 5 km / h.

  In step S104, it is determined whether or not the drive torque T of the drive wheels 10FL and 10FR is equal to or greater than the drive torque limit value Tl. If the drive torque T is equal to or greater than the drive torque limit value Tl, the process proceeds to step S106. On the other hand, when the drive torque T is less than the drive torque limit value Tl, the process proceeds to step S110 without executing the standby traction control.

  Here, with reference to FIG. 3, how to obtain the drive torque limit value Tl will be described. FIG. 3 is a flowchart showing a procedure for calculating the drive torque limit value Tl. This process is repeatedly executed at a predetermined timing during vehicle travel, and the drive torque limit value Tl set during travel is used at the next start after the vehicle stops.

  In step S200, a determination is made as to whether basic traction control is being executed. Here, when the basic traction control is being executed, that is, when the drive wheels 10FL and 10FR are slipping, the process proceeds to step S202. On the other hand, when the basic traction control is not being executed, that is, when the drive wheels 10FL and 10FR are not slipping, the process proceeds to step S204.

In step S202, the road surface friction coefficient μ is calculated from the longitudinal acceleration Gx and the lateral acceleration Gy of the vehicle HV by the following equation. Appropriate filtering processing may be performed so that the road surface friction coefficient μ increases with good responsiveness, and when it decreases, it gradually decreases.

ここで、Ｗは車両重量、ｒはタイヤ半径である。なお、車両重量Ｗ及びタイヤ半径ｒは既知の値である。 Then, a drive torque limit value Tl is calculated from the calculated road surface friction coefficient μ by the following equation.

Here, W is the vehicle weight and r is the tire radius. The vehicle weight W and the tire radius r are known values.

  After calculating the drive torque limit value Tl based on the road surface friction coefficient μ, the present process is temporarily exited. The drive torque limit value Tl may be calculated by substituting the longitudinal acceleration Gx of the vehicle HV into the above equation (2).

  In step S204, a determination is made as to whether the vehicle HV is moving backward. If the vehicle HV is moving backward, the process proceeds to step S206. On the other hand, when the vehicle HV is moving forward, the process proceeds to step S208.

  In step S206, the coefficient corresponding to the road surface friction coefficient μ equivalent torque calculated by the above equations (1) and (2) and the longitudinal acceleration Gx equivalent torque calculated by substituting the longitudinal acceleration Gx into the above equation (2). The larger of the torque values multiplied by k is set as the drive torque limit value Tl. Thereafter, the process is temporarily exited.

  In step S208, a determination is made as to whether standby traction control is being executed. If standby traction control is being executed, the process proceeds to step S210. On the other hand, when the standby traction control is not being executed, the process temporarily exits.

  In step S210, a predetermined initial value is set as the drive torque limit value Tl. Here, for the predetermined initial value, for example, a driving torque value corresponding to the maximum road surface friction coefficient (for example, 1.0) is used. Thereafter, the process is temporarily exited.

  Returning to FIG. 2, the processing procedure for standby traction control will be described. If the drive torque T is equal to or greater than the drive torque limit value Tl, standby traction control is executed in step S106.

  Here, FIG. 4 shows changes in driving torque during standby traction control. When the standby traction control is not executed, the output of the electric motor 40 is controlled so that the required drive torque Td indicated by the broken line and the drive torque T of the drive wheels 10FL and 10FR coincide. On the other hand, when the standby traction control is executed, as shown by the solid line in FIG. 4, the increase in the actual drive torque T of the drive wheels 10FL and 10FR is limited by the drive torque limit value Tl. Thereafter, the output of the electric motor 40 is controlled so that the actual driving torque T gradually increases from the driving torque limit value Tl to the required driving torque Td. If slip occurs in the drive wheels 10FL and 10FR when the drive torque T is gradually increased, the standby traction control is stopped and the basic traction control is executed.

  Returning to FIG. 2, the processing procedure for standby traction control will be described. In step S110, a determination is made as to whether standby traction control is being executed. If standby traction control is being executed, the process proceeds to step S112. On the other hand, when the standby traction control is not being executed, the process temporarily exits.

  In step S112, a determination is made as to whether basic traction control is being executed. Here, when the basic traction control is being executed, the process proceeds to step S120. On the other hand, when the basic traction control is not being executed, the process proceeds to step S114.

  In step S114, it is determined whether or not the speed Vx of the vehicle HV is greater than a predetermined value Vc. Here, if the speed Vx of the vehicle HV is greater than the predetermined value Vc, the process proceeds to step S120. On the other hand, when the speed Vx of the vehicle HV is equal to or lower than the predetermined value Vc, the process proceeds to step S116. Note that the predetermined value Vc is set to 10 km / h, for example, because standby traction control is executed only in a predetermined low speed region.

  In step S116, a determination is made as to whether a predetermined time has elapsed after the standby traction control is started. Here, when a predetermined time has elapsed after the start of the standby traction control, the process proceeds to step S120. During standby traction control, the driving torque is kept lower than the required driving torque, so a time guard is provided to prevent deterioration of drivability. On the other hand, when the predetermined time has not yet elapsed, the process proceeds to step S118.

  In step S118, it is determined whether or not the road surface friction coefficient μ obtained from the longitudinal acceleration Gx of the vehicle HV is greater than a predetermined value. If the road surface friction coefficient μ is larger than the predetermined value, the process proceeds to step S120. This is because standby traction control is stopped in the case of a road surface where acceleration of a predetermined value or more can be obtained in order to prevent deterioration of drivability. On the other hand, when the road surface friction coefficient μ is equal to or less than the predetermined value, the process temporarily exits without stopping the standby traction control.

  If any of steps S112, S114, S116, and S118 is positive, standby traction control is stopped in step S120. Thereafter, the process is temporarily exited.

  According to this embodiment, when the vehicle starts, the drive torque T of the drive wheels 10FL and 10FR can be transmitted to the road surface obtained from the drive torque limit value T1, that is, the latest estimated road surface friction coefficient μ or the vehicle longitudinal acceleration Gx at the time of slip. When the driving torque exceeds a certain value, an increase in the output of the electric motor 40 is suppressed, so that it is possible to prevent an initial slip at the start.

  According to the present embodiment, the drive torque T of the drive wheels 10FL, 10FR is gradually increased from the drive torque limit value Tl to the required drive torque Td, so that the drive wheels 10FL, 10FR start so as not to slip. And a sudden increase in the slip amount during vehicle acceleration is suppressed. Therefore, it becomes possible to improve the vehicle stability at the time of starting acceleration.

  In addition, according to the present embodiment, every time standby traction control is executed, a driving torque value corresponding to the maximum road surface friction coefficient is set as the driving torque limit value Tl, and the driving torque limit value Tl is reset. Even when the road surface friction coefficient μ increases, it is possible to prevent the drive torque from becoming insufficient when the vehicle starts next time. As a result, it is possible to prevent deterioration of drivability.

  Furthermore, according to the present embodiment, since the vehicle is started by the electric motor 40, the output torque control delay is small and the output torque can be accurately estimated. Therefore, it is possible to appropriately control the drive torque of the drive wheels 10FL and 10FR.

  As mentioned above, although embodiment of this invention was described in detail, this invention is not limited to the said embodiment, A various deformation | transformation is possible. For example, in the above embodiment, the traction control device 1 is mounted on the hybrid vehicle HV, but the configuration of the power plant 20 of the hybrid vehicle HV is not limited to the above embodiment. In addition to the hybrid vehicle, the vehicle can be mounted on an electric vehicle or a vehicle driven by the output of only the engine.

  In the above embodiment, the electronic control unit 70 is configured by the TRC ECU 71, the HV ECU 72, and the motor ECU 73 that are coupled via the communication line 76. However, the electronic control unit 70 is not limited to the above configuration, and may be configured by, for example, a single ECU. May be.

It is a block diagram which shows the structure of the principal part of the hybrid vehicle carrying the traction control apparatus which concerns on this embodiment. It is a flowchart which shows the process sequence of the standby traction control by the traction control apparatus which concerns on embodiment. It is a flowchart which shows the procedure of the calculation process of the driving torque limit value used for standby traction control. It is a figure which shows the drive torque change in the standby traction control by the traction control apparatus which concerns on embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Traction control apparatus, 10FL ... Left front wheel, 10FR ... Right front wheel, 20 ... Power plant, 21 ... Engine, 28 ... Transmission, 30 ... Differential, 32 ... Transfer, 34 ... Propeller shaft, 36L, 36R ... Drive shaft, 40 DESCRIPTION OF SYMBOLS ... Electric motor, 50 ... Inverter, 60 ... High voltage battery, 70 ... Electronic control unit, 71 ... TRC ECU, 72 ... HV ECU, 73 ... Motor ECU, 77 ... Front / rear left / right acceleration sensor, 78FR, 78FL, 78RR, 78RL ... Wheel Speed sensor, 79 ... accelerator position sensor, HV ... hybrid vehicle.

Claims (5)

A driving force source for driving the driving wheels of the vehicle;
Road surface friction coefficient estimating means for estimating the friction coefficient of the road surface;
Starting torque calculating means for setting a driving torque limit value at the time of starting based on the road surface friction coefficient estimated by the road surface friction coefficient estimating means during traveling of the vehicle;
Drive torque detection means for detecting the drive torque of the drive wheels;
Control means for suppressing an increase in the output of the driving force source when the driving torque detected by the driving torque detecting means is greater than or equal to the driving torque limit value set during the previous travel when starting the vehicle; A traction control device comprising: A driving force source for driving the driving wheels of the vehicle;
Slip detecting means for detecting slip of the drive wheel;
Acceleration detecting means for detecting acceleration of the vehicle;
Starting torque calculating means for setting a driving torque limit value at the time of starting based on the acceleration detected by the acceleration detecting means when the slip detection means detects slipping of the driving wheel during traveling of the vehicle;
Drive torque detection means for detecting the drive torque of the drive wheels;
Control means for suppressing an increase in the output of the driving force source when the driving torque detected by the driving torque detecting means is greater than or equal to the driving torque limit value set during the previous travel when starting the vehicle; A traction control device comprising: Based on the amount of operation of the accelerator pedal, a required drive torque calculating means for calculating a required drive torque requested by the driver is provided,
The said control means controls the output of the said driving force source so that the drive torque of the said driving wheel may approach the said request | requirement drive torque gradually from the said drive torque limit value. Traction control device.   The starting torque calculating means sets a predetermined initial value for the driving torque limit value when the driving torque detected by the driving torque detecting means at the time of starting the vehicle becomes equal to or greater than the driving torque limit value. The traction control device according to any one of claims 1 to 3. The traction control device according to claim 1, wherein the driving force source is an electric motor.

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