JPH11159365A - Slip ratio control device for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately control the slip ratio even in the condition that a gravity acceleration is large such as on a slope by setting a slip ratio determining function, and setting the driving and braking torque target value on the basis of the switching function containing the integral term obtained by performing time-integration of the determining function. SOLUTION: Each detection value of a wheel speed sensor 7 and a car speed sensor 8 is input to a control unit 3 with a target slip ratio to be set on the basis of the output of an acceleration pedal actuating angle sensor 9 so as to compute a slip ratio determining function σ (t). A switching function containing the integral term obtained by performing the time-integration of the slip ratio determining function valve is set, and a driving and braking torque target value of a driving wheel is set on the basis of the switching function. The slip ratio determining function σ (t) is determined by an expression σ(t)=γXv (t)-Xw (t)-γ0 (t), and γ0 >=0, γ=1/(1-λ0 ), Xv (t) means car body speed, Xw (t) means driving wheel speed, λ0 means a target slip ratio, and λ means slip ratio.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slip ratio of a vehicle for reducing a decrease in an acceleration force and a wasteful consumption of energy due to excessive slipping of a wheel with a road surface when the vehicle starts or accelerates. The present invention relates to a control device.

[0002]

2. Description of the Related Art As means for controlling a slip ratio so as not to cause excessive slip of a driving wheel at the time of starting or accelerating an automobile, for example, the following document is disclosed. [1] Matsuda et al .: Development of Nissan type four-wheel anti-lock device,
Nissan Gijutsu, No. 20, p111-p118 (1984) [2] Han-Shue Tan, Yuen-Kwok
Chin: Vehicle Traction Co
ntrol: Variable-Structure
Control Approach, Journal
of Dynamic Systems, Measur
element, and Control, p223-p2
30 (1991) [3] JP-A-9-88655

[0003] The above-mentioned document [1] discloses a method of controlling by switching the brake fluid pressure in accordance with the calculated pseudo vehicle body speed and wheel speed. On the other hand, Literatures [2] and [3] show a control method for detecting a slip ratio and then designing a control system theoretically and efficiently using a sliding mode control theory. In the control method of the document [2], the braking / driving force is adjusted according to the slip ratio and the time change amount of the slip ratio. However, in the control method of the document [3], the braking / driving is performed according to a linear combination value of the wheel speed and the vehicle speed. Adjusting the torque.

[0004]

However, the above-mentioned conventional vehicle slip ratio control means has the following problems. In the method of Document [1], the conditions for switching the brake fluid pressure are set, but a trial-and-error method must be used in accordance with the vehicle speed and the wheel speed. May take some time.
In the method of Document [2], it is necessary to know the time change amount of the slip ratio in order to set the braking / driving torque target value. It is difficult with sensing technology.

The method of Reference [3] solves the problem of Reference [2] by the following method. This is to adjust the braking / driving torque in accordance with a linear combination value (hereinafter, referred to as a slip ratio determination function) of the vehicle speed and the driving wheel speed, which are easily detected, instead of the slip ratio and the time change amount of the slip ratio. . Here, in Reference [3], the target braking / driving torque during driving is derived as follows. First, the slip ratio determination function σ _i is calculated as follows. σ _i (t) = ηX _v (t) −X _wi (t) (1) where i is a subscript indicating a wheel number. For example, if the driving wheels are two front wheels, the wheel speed of the right front wheel is X _w1 (t),
Let the wheel speed of the left front wheel be X _w2 (t). A slip ratio determination function σ _i is calculated for each of the driving wheel speeds. η is a predetermined value, and is determined by the following equation from the target value λ ₀ of the slip ratio between the road surface and the tire. η = 1 / (1-
λ ₀ ), 0 <λ ₀ <1 is a target slip ratio, X _v = V / R _w is a vehicle speed, where V is a vehicle speed, R _w is a wheel radius, and X _w is a driving wheel speed (wheel rotational angular speed). It is. λ ₀ is a numerical value that is set, for example, in proportion to the depression angle of the accelerator pedal. The slip ratio λ _i during acceleration is defined by the following equation. λ _i (t) = (X _wi (t) −X _v (t)) / X _wi (t) (2) According to these formulas, the sign of the formula (1) is obtained when the slip ratio is larger than the target value. σ _i > 0, σ _i <0 when the slip ratio is smaller than the target value, and σ _i = 0 when the slip ratio matches the target value.

Next, a switching function S _i (t) is calculated by the following equation using a predetermined gain K _I > 0.

[0007]

(Equation 1) However, t is the current time, t ₀ is the control start time, K _I is a positive constant predetermined. The braking / driving torque target value U _cmdi of each drive wheel is determined by the following equation. _{U cmdi (t) = J w} q i (t) (4) q i (t) = q i - (S i (t) ≦ 0) (5-1) q i (t) = f (S i) (0 <S _i (t) ≦ δ) (5-2) q _i (t) = q _i ⁺ (S _i (t)> δ) (5-3) f (S _i ) is f (0) = Q _i ⁻ , f (δ) = q _i ⁺ . J _w , q ⁺ , and δ are positive constants, and q ⁻ is a constant (q ⁺ <q ⁻ ). Also, q
The relationship between _i (t) and S _i (t) is shown, for example, in FIG. q _i ^- and q _i ⁺ are constants satisfying the following conditions. ^{_{q i + <f resisti -ηX v}} (t) -fμ i -K I σ i (t) (6) q i -> f resisti -ηX v (t) -fμ i -K I σ i (t) ( 7) Here, fμ _i is the longitudinal force exerted by the road surface on the ith wheel,
f _resisti is the rolling resistance of the i-th wheel. fμ _i , f
_resisti, X _{v, σ i} is q _i ⁺ satisfying since takes a finite value in the formula (6) (7) in any case, q _i ^- always exists. FIG. 6 is a graph showing q _i (t).

[0008] Here, q _i ^- a value so that a large as possible, and even if such as during acceleration of the acceleration of gravity is greater uphill, it is possible to approximate the slip ratio to the target slip rate . For this reason, the maximum value q _i of the drive torque that may occur ^- it is desirable to take large as possible.

However, when the value of q _i ^- is set to be large, the following problem occurs. In the case of starting acceleration, the initial state is _Xv (0) = 0, _Xwi (0) = 0. for that reason,
From equations (1) and (3), σ _i (0) = 0, S _i (0) = 0
_{Next, U cmdi (0) = q} i - become. This means that a large driving force is suddenly applied at the start of control. Even with such a control method, if the delay in detection by the sensor and the delay in drive torque generation can be ignored, the sliding mode control theory can prove that the slip ratio rapidly converges to the target value. Delays and delays in drive torque generation cannot be ignored. Therefore, when q _i ^- is large, FIG.
As shown in the graphs (a) and (b), both S _i (t) and U _cmdi (t) increase in the initial state at the time t, and accordingly, the actual slip ratio λ _i (t) becomes the graph ( As shown in c), excessive wheel spin may occur due to the excessive wheel spin.

[0010] To avoid such a problem, in the above [3], until the predetermined value theta ₀ with the accelerator pedal depression angle, giving a drive torque target value outlined proportional to the accelerator pedal depression angle premise to, start the control when the accelerator pedal depression angle than theta ₀ becomes larger. However, if θ ₀ is not set to a small value on a slippery road surface, the slip ratio becomes excessive before the start of control. On a slippery road surface, if θ ₀ is small, the slip ratio does not sufficiently occur, that is, S _i (t) <0. Since the control is started from the state described above, a large drive torque target value q _i ^- is suddenly generated, and the slip ratio may become excessively large in combination with the detection delay and the torque generation delay. Thus, it is desirable to change θ ₀ according to the slipperiness of the road surface, but there is a problem that it is difficult to know the slipperiness of the road surface in advance.

Accordingly, the present invention provides a vehicle slip rate control device which can control the slip rate accurately even in a state where gravitational acceleration such as a slope is large, in which wheel spin hardly occurs at the time of starting acceleration.

[0012]

According to a first aspect of the present invention, there is provided a vehicle slip rate control apparatus, comprising: a vehicle speed detector; a drive wheel speed detector; and an accelerator pedal. Depressed angle detecting means, target slip rate setting means for setting a target slip rate of the drive wheels according to the detected value of the accelerator pedal depressed angle, and a detected value obtained by the vehicle speed detecting means and a drive wheel speed detecting means Means for calculating a slip rate determination function by using the detection value obtained in step 1 and the set value set by the target slip rate setting means as input, and a slip rate determination function calculation unit for determining a slip state of the drive wheels at the present time based on the calculated value. A torque target value setting means for inputting a slip ratio determination function value calculated by a slip ratio determination function operation unit and setting a braking / driving torque target value of a driving wheel according to the slip ratio determination function value; In the slip ratio control apparatus for a motor vehicle having a braking and driving torque adjusting means for adjusting in response to the braking and driving torque target value to set the torque target value setting means for braking or driving torque of wheels, the slip ratio determination function σ
A value obtained by multiplying a constant γ determined according to the target slip ratio λ ₀ by a vehicle speed X _v (t) as defined by the following equation (A), a driving wheel speed X _w (t) , Which is a linear combination with a variable γ ₀ (t) that does not increase from the control start time. Formula (A): σ (t) = γX v (t) -X w (t) -γ 0 (t) , _{however, γ 0 ≧ 0 γ = 1} / (1-λ 0) ( of X _v> X _w H) γ = λ ₀ -1 (when X _v <X _w ) σ (t): slip ratio determination function, X _v (t): body speed, X _w (t): drive wheel speed, λ ₀ : target Slip ratio, λ: Slip ratio

Further, according to a second aspect of the present invention, there is provided the vehicle slip ratio control apparatus, wherein the slip ratio determination function σ (t)
Is calculated using a variable γ ₀ (t) of the following equation (B) that attenuates exponentially with a predetermined time constant. Equation (B): γ ₀ (t) = γ ₀ (0) e- ^Tt where T: time constant, t: time, γ ₀ (0): preset initial value of γ ₀ (t)

According to a third aspect of the present invention, there is provided a vehicle slip ratio control apparatus according to the third aspect of the present invention, wherein a variable γ ₀ (t) that does not increase from the control start time exceeds a predetermined value at which the slip ratio is smaller than the target slip ratio. It is characterized in that it is constant and becomes zero after the absolute value of the slip ratio exceeds the predetermined value at least once.

According to a fourth aspect of the present invention, in the vehicle slip ratio control device, the torque target value setting means is a linear compensator represented by a transfer function matrix.

According to a fifth aspect of the present invention, in the vehicle slip ratio control apparatus, the transfer function matrix is a PI compensator based on a combination of proportional / integral operations or a PID based on a combination of proportional / integral / derivative operations. It is characterized in that a compensator is a constituent element.

According to a sixth aspect of the present invention, in the vehicle slip rate control device, the torque target value setting means includes a torque target value corresponding to a sign of an output of a transfer function matrix having a slip rate determination function value as an input. It is characterized by setting a value.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a vehicle slip rate control apparatus according to the present invention will be described below in detail with reference to FIGS. As shown in FIG. 1, the engine 1 varies the output torque according to the opening of the intake throttle 2.
The output torque is transmitted to the left and right drive wheels 5a, 5b via a torque distributor 4 which distributes the torque in response to the output signal of the control unit 3, and drives the drive wheels 5a, 5b to rotate. The opening and closing of the intake throttle 2 is performed by an accelerator pedal 6. The control unit 3, the drive wheels 5a, the wheel speed sensor 7 for detecting the rotational speed X _wi (t) of 5b, the vehicle speed sensor 8 for detecting the vehicle body speed X _v (t), depression angle of an accelerator pedal 6 A signal from the accelerator pedal depression angle sensor 9 for detecting θ (t) is input. The wheel speed sensor 7 is provided for each of the two drive wheels 5a, 5b. The vehicle speed sensor 8 includes, for example, an acceleration sensor that detects a longitudinal acceleration α acting on the vehicle body, and an integrator that integrates the output of the acceleration sensor. Alternatively, in the control unit 3, the vehicle speed X is calculated by the following equation.
_v (t) may be calculated.

[0019]

(Equation 2) Here, X _v (t ₀ ) is an initial value, and R _w is a wheel radius.
Further, a wheel speed sensor may be provided for the non-driving wheels 10a and 10b, and the rotational speed of the non-driving wheels 10a and 10b may be detected and used as the vehicle speed X _v (t). Control unit 3
Is composed of, for example, a microcomputer. The following equation (8) is used for each signal of the input drive wheel speed X _w (t), vehicle body speed X _v (t), and accelerator pedal depression angle θ (t). The target drive torque U _cmdi (t) is _obtained from (19).

First, the slip ratio determination function σ _i (t) is defined by the following equation obtained by modifying the conventional equation (1). σ _i (t) = γX _v (t) −X _wi (t) −γ ₀ (t) (8) where γ ₀ ≧ 0 and i is a subscript indicating the wheel number. For example, when the drive wheels 5a and 5b are two front wheels, the wheel speed of the right front wheel is X _w1 (t), and the wheel speed of the left front wheel is X _w2 (t). γ is a predetermined value and is determined from the target value λ ₀ of the slip ratio between the road surface and the tire by the following equation. γ = 1 / (1−λ ₀ ) (when X _v > X _wi ) (9-1) γ = λ ₀ −1 (when X _v <X _wi ) (9-2) where λ ₀ is For example, the depression angle θ of the accelerator pedal
It is a numerical value set according to (t). The measured value λ _i of the slip ratio between the road surface and the tire is defined by the following equation. λ _i = (when _{X v <X w) (X} wi (t) -X v (t)) / X wi (t) (10-1) λ i = (X wi (t) -X v (t )) / X _v (t) (when X _v > X _w ) (10-2) Here, when γ ₀ = 0, σ _{i is obtained} from the definition equation (8).
(T) = 0 means that the slip ratio λ _i matches the target slip ratio λ ₀ . σ _i (t)> 0 means that the slip ratio is smaller than the target value, and σ _i (t) <0 means that the slip ratio is larger than the target value.

Next, a switching function S _i (t) including an integral term obtained by time-integrating the judgment function σ _i (t) is calculated by the following equation.

[0022]

(Equation 3) However, t is the current time, K _I is a positive constant predetermined. From this equation (11), the driving wheels 5a, 5b
The braking and driving torque target value _U cmdi (t) is determined by the following equation using a gain K _u> 0 a predetermined. U _cmdi (t) = − K _u S _i (t) (12) Equation (11) is a PI-type control. To make this a PID-type control, instead of equation (11),

[0023]

(Equation 4) And it is sufficient. Where σ _i ′ is a pseudo differential value of σ _i ,
For example, σ _i is obtained by processing with a high-pass filter. K _p
Is a gain determined by the designer.

Further, the relational expressions (5-1) to q _i (t) and S _i (t) disclosed in Japanese Patent Application Laid-Open No. 9-88655 are disclosed.
(5-3) is modified as follows. FIG. 4 shows this relationship in a graph. q _i (t) = q _i ⁺ (S _i (t)> δ) (14-1) q _i (t) = f (S _i ) (−δ ≦ S _i (t) ≦ δ) (14-2) ) Q _i (t) = q _i ⁻ (S _i (t) <− δ) (14-3) However, the derivation of S _i is the same as in equations (11) and (13). Next, the braking / driving torque target value is given by U _cmdi (t) = K _u q _i (t) (15). In equations (14-1) to (14-3), -δ
When ≦ S _i ≦ δ, U _cmdi is a constant corresponding to the sign of S _i , and if the absolute values of q _i ⁻ and q _i ⁺ are sufficiently large, the target slip ratio can be reduced from the case of equation (12). Converges faster. When the target braking / driving torque of the equations (12) and (15) is given by the function of the integrator of the equation (11) or (13), σ _i approaches zero. If γ ₀ is 0, the actual slip ratio approaches the target slip ratio as a result of γ approaching 0. However, even if σ _i = 0, if γ ₀ is not equal to 0, the slip ratio will deviate from the target value according to the magnitude of γ ₀ .

Therefore, γ ₀ (t) in the equation (8) is ^replaced by the following equation: γ ₀ (t) = γ ₀ (0) e− ^Tt (16) where t is time, T is a time constant, γ ₀ (0) )> 0 is a preset initial value of γ ₀ (t). In this case, at the time of start (t = 0), U _cmdi (0) = K _u γ ₀ (0) (17), so that the value of γ ₀ is made sufficiently small as shown in FIG. If it is given, no excessive braking / driving torque is generated at the time of starting, and as time passes, γ
_Since the absolute value of ₀ (t) decreases, the error between the slip ratio and the target slip ratio also decreases.

Γ ₀ (t) is a condition of the following equation γ ₀ (t) = γ ₀ (t) (where λ (t) has not exceeded λ ₁ ) (18-1) γ ₀ ( t) = 0 (lambda (t) is the same effect can be obtained even when) (18-2) who have exceeded lambda _1. Here, λ ₁ is selected so that its size does not exceed λ _0, for example, λ ₁ = K _× λ ₀ (0 <K _x <1) (19). If λ ₁ is selected in such a manner, even if γ ₀ (0) is selected to be large, the effect of γ ₀ (0) disappears before the slip ratio reaches the target slip ratio, and the slip ratio is controlled so as to match the target value. You.

Further, as shown in the conventional example, even when the braking and driving torque target value comprises a constant depending on the sign of S _i, gamma ₀ value of (0) q _i ^- values The Since it can be set separately, q _i ^- can be set large without considering the wheel spin at the time of starting acceleration, and the slip ratio can be accurately controlled even on a slope or the like.

Next, the above calculation and control by the control unit 3 will be described with reference to FIGS. The control unit 3 repeats the series of flows shown in FIG. 3 at a predetermined sampling period. First, in step S1, the control unit 3 detects the wheel speed of the left and right driving wheels 5a, 5b from the wheel speed sensor 7. For example, in the case of a front wheel drive vehicle, the rotational speeds of the right front wheel and the left front wheel are detected.
In step S2, the average value ( _Xw ) is obtained. Instead of this average value (X _w ), the larger of the rotation speeds of the right driving wheel and the left driving wheel may be set as X _w . Towards the rotational speed greater will control the slip ratio relative to the larger sliding of the left and right drive wheels and the X _w. Next, step S3
, The control unit 3 detects the rotational speeds of the non-driven wheels 10a and 10b from the vehicle speed sensor 8 and sets the detected rotational speed as the vehicle speed _Xv . In step S4, the depression angle θ (t) of the accelerator pedal 6 is read. The accelerator pedal depression angle sensor 9 is a potentiometer attached to the axis of the accelerator pedal 6 and controls the control unit 3.
Detects the accelerator pedal depression angle θ from the accelerator pedal depression angle sensor 9. In step S5, the target slip ratio is set from the detection result using the target slip ratio setting means 20. This setting means sets the target slip ratio λ ₀ from the accelerator pedal depression angle θ as follows. λ ₀ = (θ−θ _min ) / (θ _max −θ _min ) (20) where θ _min is the minimum value of the accelerator pedal depression angle θ, θ
_max is the maximum value of the accelerator pedal depression angle θ. That is, λ ₀ = 0 when θ = θ _min , λ ₀ = 1 when θ = θ _max , and λ ₀ is complemented by a linear characteristic between θ _min and θ _max . Based on the target slip ratio, a slip ratio determination function calculation is performed in step S6. The slip ratio determination function calculator 21 that performs this calculation calculates the slip ratio determination function value of Expression (8). Here, γ ₀ (t) is calculated by the equation (1)
6) or calculated using equation (18).

Next, the torque target value setting means 22 calculates the torque target value U _cmdi based on the equation (11) or (13) and the equation (12). Or the formula (1
1) or (13) and equations (14-1) to (14-
3) Calculate the torque target value U _cmdi based on equation (15).

The braking / driving torque adjusting means 23 comprises a target value distributing means 23a, a brake torque adjusting means 23b, and an engine torque adjusting means 23c. The target value distributing means 23a receives the braking / driving torque target value U _cmdi and _{sets the} brake torque target value τ _B or the engine torque target value τ _E as follows.
3b and output to the engine torque adjusting means 23c. Here, τ _B and τ _E are set as follows. τ _B = U _cmdi (U _cmdi ≦ U ₀ ) (21-1) τ _B = 0 (U _cmdi > U ₀ ) (21-2) τ _E = U _cmdi (U _cmdi > U ₀ ) (22-1) τ _E = 0 (U _cmdi ≦ U ₀ ) (22-2) Here, U ₀ <0 is a predetermined constant, and is determined according to a deceleration that can be generated by engine braking. That is, U _cmdi
If is acceleration or moderate deceleration torque, U _cmdi is generated by the engine, and if U _cmdi is a deceleration torque equal to or greater than a certain value, U _cmdi is generated by the brake. Brake torque adjusting means 2
3b adjusts the brake pressure according to τ _B. At the same time, the engine torque adjusting means 23c adjusts the throttle air valve according to τ _E. Performing the above operation efficiently based on a fixed cycle enables stable traveling.

As described above, in the conventional slip ratio determination function of the equation (1), it is difficult to adjust the torque at the time of starting acceleration corresponding to the road surface condition. By using the slip ratio determination function of (1), control can be performed in a manner close to the actual road surface condition, and reduction in acceleration force and wasteful consumption of energy can be suppressed, and smooth running can be performed.

[0032]

As described above, according to the vehicle slip rate control apparatus of the present invention, since the control is performed based on the above-described slip rate determination function, wheel spin is unlikely to occur at the time of starting acceleration, and furthermore, such as on a hill. It is possible to accurately control the slip ratio even when there is disturbance such as gravitational acceleration.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a vehicle slip ratio control device according to the present invention.

FIG. 2 is a block diagram of a vehicle slip ratio control device according to the present invention.

FIG. 3 is a flowchart of a vehicle slip ratio control device according to the present invention.

FIG. 4 is a graph showing characteristics of a control function q (t) of the vehicle slip ratio control device according to the present invention.

FIG. 5 is a graph showing the effect of the vehicle slip ratio control device according to the present invention.

FIG. 6 is a graph showing characteristics of a control function q (t) of a conventional example.

FIG. 7 is a graph showing the effect of the conventional example.

[Explanation of symbols]

 Reference Signs List 1 engine 2 intake throttle 3 control unit 5a, 5b drive wheel 6 accelerator pedal 7 wheel speed sensor 8 vehicle speed sensor 9 accelerator pedal depression angle sensor 10a, 10b non-drive wheel 23b brake torque adjustment means 23c engine torque adjustment means

Claims (6)

[Claims] 1. A target slip for setting a target slip ratio of a drive wheel according to a detected value of an accelerator pedal depression angle, a vehicle body speed detection unit, a drive wheel speed detection unit, an accelerator pedal depression angle detection unit. A slip ratio determination function is calculated by using the detection value obtained by the vehicle speed detection unit, the detection value obtained by the drive wheel speed detection unit, and the set value set by the target slip ratio setting unit. Means, a slip ratio determination function calculator for determining the slip state of the drive wheel at the present time, and a slip ratio determination function value calculated by the slip ratio determination function calculator. A torque target value setting means for setting a braking / driving torque target value for the driving wheel; A slip rate control device for a vehicle having driving torque adjusting means, wherein the slip rate determination function σ (t) is defined by a target slip rate λ ₀ as defined by the following equation (A).
Multiplied by the vehicle speed X _v (t) and the drive wheel speed X
A slip ratio control apparatus for a vehicle, wherein _w (t) is a linear combination of a variable γ ₀ (t) that does not increase from the control start time. Formula (A): σ (t) = γX v (t) -X w (t) -γ 0 (t) , _{however, γ 0 ≧ 0 γ = 1} / (1-λ 0) ( of X _v> X _w H) γ = λ ₀ -1 (when X _v <X _w ) σ (t): slip ratio determination function, X _v (t): body speed, X _w (t): drive wheel speed, λ ₀ : target Slip ratio, λ: Slip ratio 2. The method according to claim 1, wherein the slip ratio determination function σ (t) is calculated using a variable γ ₀ (t) of the following equation (B) that exponentially decays according to a predetermined time constant. Item 2. The vehicle slip ratio control device according to Item 1. Equation (B): γ ₀ (t) = γ ₀ (0) e- ^Tt where T: time constant, t: time, γ ₀ (0): preset initial value of γ ₀ (t) 3. A variable γ _{0 that} does not increase from the control start time.
2. The method according to claim 1, wherein (t) is constant until the slip ratio exceeds a predetermined value smaller than the target slip ratio, and is zero after the absolute value of the slip ratio exceeds the predetermined value at least once. Car slip rate control device. 4. The vehicle slip ratio control device according to claim 1, wherein said torque target value setting means is a linear compensator represented by a transfer function matrix. 5. The transfer function matrix according to claim 4, wherein a PI compensator based on a combination of proportional / integral operations or a PID compensator based on a combination of proportional / integral / derivative operations is a component. Car slip rate control device. 6. The vehicle according to claim 4, wherein said torque target value setting means sets a torque target value according to a sign of an output of a transfer function matrix to which a slip rate determination function value is input. Slip rate control device.