JPH1155809A - Electric car controlling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric car controlling device capable of performing a slip control reliably even in the state that all shafts are slipping. SOLUTION: A wheel speed detecting part 2 is provided on an electric car 1, and rotating speed ωr1 to ωr4 are inputted into a controlling part 3. A car body speed presuming part 31 presumes and outputs car body speed ωrT based on the input of the rotating speed ωr1 to ωr4. A slip speed calculating part 32 inputs the car body presumed speed ωrT and the wheel speed ωr1 to obtain and output slip speed Δωr. An all-shaft slip detecting part 33 determines whether or not all the shafts are slipping (whether or not there is such a sign) to output a detection flag FlgZEN. An all-shaft slip controlling torque reducing part 34 inputs the FlgZEN to obtain and output a torque command TrqRef1. If there is a sign that all the shafts may slip, torque is reduced on a motor having the rotating speed of ωr1 in the electric car 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electric vehicle control device.

[0002]

2. Description of the Related Art An electric vehicle is formed by connecting a plurality of vehicles. In an electric vehicle equipped with a plurality of electric motors in the same vehicle, in order to increase the adhesive force between the wheels and the rails to suppress idling, among the rotation frequencies of the plurality of electric motors, the minimum value during power running is set to the lowest value, The maximum value is defined as the vehicle speed, and the difference between the rotation frequency of each motor and the vehicle speed is defined as the idling speed, and the torque of each motor is increased or decreased so as to reduce the idling speed.

[0003]

However, when the adhesive force (frictional force) between the wheels and the rails is generally small, such as during heavy rain or flood, they are assembled into the same vehicle. In many cases, all axes idle.
In this case, the lowest value of the shaft driven by the electric motor does not indicate the vehicle body speed, and there is a case where the idling control does not operate even though the idling actually occurs. At this time, since the idling speed is increased, there is a problem in that the riding comfort is deteriorated, the frictional force between the wheels and the rail cannot be effectively used, and the acceleration force is insufficient.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an electric vehicle control device capable of performing idle control reliably even in a state in which all axes idle. With the goal.

[0005]

In order to achieve the above-mentioned object, the invention according to claim 1 is provided in a plurality of vehicles constituting an electric vehicle, and controls the rotation speed of an electric motor connected to wheels. A plurality of wheel speed detecting means for detecting each,
Vehicle speed estimating means for estimating the vehicle speed of the electric vehicle based on rotation speeds detected by one or more wheel speed detecting means among the wheel speed detecting means provided on the same vehicle; A plurality of slip speed calculating means for calculating a slip speed based on the vehicle speed and the rotational speed detected by the own wheel speed detecting means; and a plurality of slip speed calculating means provided for each of the wheel speed detecting means. All of the wheels corresponding to one or more wheel speed detecting means used for estimating the vehicle speed are based on the slip speed calculated by the slip speed calculating means corresponding to the own wheel speed detecting means. A plurality of all-axis idling detecting means for detecting signs; and an all-axis idling detecting means provided for each of the wheel speed detecting means and corresponding to its own wheel speed detecting means. When it is detected, it and a plurality of torque throttle means to lower the torque of the electric motor detected by the own wheel speed detection means.

According to a second aspect of the present invention, in the first aspect of the present invention, the all-axis idling detecting means keeps the idling speed at a predetermined reference idling speed for a predetermined time or more. When it exceeds, a sign of idling is detected.

According to a third aspect of the present invention, a plurality of wheel speed detecting means provided in a plurality of vehicles constituting an electric vehicle and detecting the rotational speed of an electric motor connected to wheels are provided in the same vehicle. A vehicle speed estimating unit for estimating a vehicle speed of the electric vehicle based on rotation speeds detected by one or more wheel speed detecting units of the provided wheel speed detecting units; And two wheel speed detecting means for calculating the idling speed for each of the two or more wheel speed detecting means based on the rotational speeds detected by two or more wheel speed detecting means among the wheel speed detecting means provided in the vehicle. A wheel corresponding to one or more wheel speed detecting means used for estimating the vehicle body speed based on the above-described slip speed calculating means and the slip speed calculated by the slip speed calculating means; All-axis idling detection means for detecting signs of all slipping, and when the all-axis idling detection means detects signs of idling, torque for reducing the torque of the motor connected to the wheel where the sign of idling was detected Aperture means.

According to a fourth aspect of the present invention, in the third aspect of the present invention, the all-axis idling detecting means is one of the idling speeds calculated by two or more idling speed calculating means.
When the minimum value of the absolute value continuously exceeds a predetermined reference slip speed for a predetermined time or more, a sign of slip is detected.

According to a fifth aspect of the present invention, a plurality of wheel speed detecting means provided in a plurality of vehicles constituting an electric vehicle and each detecting a rotational speed of an electric motor connected to a wheel are provided in the same vehicle. Vehicle speed estimating means for estimating the vehicle speed of the electric vehicle based on the rotation speed detected by one or more wheel speed detecting devices of the wheel speed detecting devices, and Based on the rotational speeds detected by two or more wheel speed detecting means among the provided wheel speed detecting means,
Two or more slip speed calculating means for calculating the slip speed for each of the at least one wheel speed detecting means, and 1 or 2 used for estimating the vehicle speed based on the slip speed calculated by the slip speed calculating means. The all-axis idling detecting means for detecting a sign that all the wheels corresponding to at least one wheel speed detecting means are idling, and the idling speed calculating means is operated when the sign of the idling is detected by the all-axis idling detecting means. Torque limiting means for reducing the torque of the motor connected to the wheel corresponding to the wheel speed detecting means having the minimum absolute value of the idle speeds.

According to a sixth aspect of the present invention, in the first aspect of the present invention, when a plurality of all-axis idling detection units simultaneously detect a precursor of idling, the motor is controlled by a plurality of torque reduction units. It is characterized in that the torque reduction control is shifted.

According to a seventh aspect of the present invention, in the first aspect of the present invention, the vehicle body speed estimating means is provided by two or more wheel speed detecting means provided in the same vehicle. Among the detected rotational speeds, the vehicle body speed is estimated based on a minimum value during power running of the electric vehicle and a maximum value during regeneration.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a configuration diagram of an electric vehicle control device according to a first embodiment of the present invention. Although only one vehicle is shown in the drawing, the electric vehicle is configured by connecting a plurality of such vehicles.

The vehicle 1 is provided with a wheel speed detecting unit 2 for detecting a rotating speed of an electric motor connected to the wheels, and the rotational speed detected by the wheel speed detecting unit 2 (the electric motor is provided on each shaft). Ωr1 to ωr4 are input to the control unit 3.

The control unit 3 is provided for each wheel provided with the wheel speed detection unit 2. In the present embodiment, the control unit 3 is provided for a wheel having a rotation speed of the electric motor of ωr1. The corresponding control units are omitted because they have the same configuration. The control unit 3 includes a vehicle speed estimating unit 31, an idling speed calculating unit 32, an all-axis idling detecting unit 33, and an all-axis idling suppressing torque throttle unit 34.

The vehicle speed estimating section 31 includes a wheel speed detecting section 2
The rotation speeds ωr1 to ωr4 detected as inputs are input, and the vehicle speed ωrT is estimated and output. The configuration of the vehicle speed estimating unit 31 is, as shown in FIG.
1, differentiator 312, vehicle acceleration estimator 313, adder 3
14, integration section 315, subtraction section 316, steady-state deviation correction section 3
17.

The selector 311 determines the rotation speeds ωr1 to ωr
4 is input and the minimum wheel speed is output as the wheel speed ωrM when the electric vehicle is running (when accelerating) and the maximum wheel speed when the electric vehicle is regenerating (when decelerating). The differentiator 312 receives the wheel speed ωrM output from the selector 311,
The acceleration αωM is obtained from the equation (1) and output.

[0017]

ΑωM = s · ωrM (1) (where s is a differential operator)
The acceleration αωM output from the differentiator 312 is input,
The estimated vehicle body acceleration value αT is obtained from the equation (2) and output.

[0018]

ΑT = αωM / (1 + T · s) (2) (where T is a temporary delay filter time constant and s is a differential operator) The addition unit 314 estimates the vehicle acceleration output from the vehicle acceleration estimation unit 313. The value αT and a steady-state error correction value △ αT output from a steady-state error correction unit 317 described later are added and output to the integration unit 315. The integrator 315 obtains and outputs the estimated vehicle speed ωrT from the equation (3).

[0019]

ΩrT = (αT + △ αT) / s (3) (where s is a differential operator) The estimated vehicle speed ωrT
May output the wheel speed ωrM output by the selection unit 311 as it is as the estimated vehicle speed ωrT.

The subtraction unit 316 calculates a deviation ΔωrT between the wheel speed ωrM output from the selection unit 311 and the estimated vehicle speed ωrT output from the integration unit 315, and outputs the result to the steady-state error correction unit 317. Then, the steady-state deviation correction unit 317
Then, the steady-state deviation correction value △ αT is obtained and output by the equation (4).

[0021]

△ αT = G (s) · △ ωrT (4) (where G (s) is a correction gain and is, for example, a positive constant) The idling speed calculation unit 32 is provided by the vehicle speed estimation unit 31 in this manner. The obtained estimated vehicle speed ωrT and the wheel speed ωr1 detected by the wheel speed detection unit 2 (in the present embodiment, the control unit 3 indicates that the rotation speed of the electric motor is provided on the wheel whose rotation speed is ωr1. Therefore, the idle speed calculation unit of the control unit corresponding to the other wheel inputs the corresponding wheel speed ωr2 to ωr4), and (5)
The slip speed △ ωr is obtained from the equation and output.

[0022]

△ ωr = ωr1−ωrT (5) The all-axis idling detection unit 33 receives the idling speed △ ωr calculated by the idling speed calculation unit 32 as an input, and performs all-axis idling (for all-axis idling). It determines whether or not there is a precursor, and outputs a detection flag FlgZEN. As shown in FIG. 3, the configuration of the all-axis idling detection unit 33 includes a subtraction unit 331 and a comparison unit 33.
2. It is composed of a rise delay section 333.

The subtraction unit 331 calculates a deviation between the slip speed △ ωr and a predetermined reference slip speed △ ωrset and outputs the result to the comparison unit 332. In the comparison unit 332, (6)
The flag FlgZENO is output according to the determination of the expression (7).

[0024]

When Δωr−Δωrset ≦ 0, FlgZENO = 0 (6) When Δωr−Δωrset> 0, FlgZENO = 1 (7) When the flag FlgZENO is input, the flag Flg
When ZENO = 1 is continuously input for a predetermined time Tset or longer, the detection flag FlgZEN = 1 is output. Otherwise, the detection flag FlgZEN =
Outputs 0.

The all-axis idling suppressing torque restricting section 34 receives the detection flag FlgZEN from the all-axis idling detecting section 33 and obtains and outputs a torque command TrqRef1. That is,
Detection flag FlgZ output from all-axis idling detection unit 33
When EN is input and the detection flag FlgZEN = 0, it is determined that all axes are not idling (there is no sign of all-axis idling), and a torque reduction amount ΔTrqZEN described later is 0, and a torque command TrqRefO from the driver's cab. With torque command T
Output as rqRef1. On the other hand, the detection flag Flg
When ZEN = 1, it is a sign that all of the axes are idling, and torque reduction control as shown in FIG. 4 is performed. In this torque restriction control, when the detection flag FlgZEN = 1, the torque restriction amount △
TrqZEN is started in steps from 0, and is reduced to 0 at a constant reduction rate. Then, the torque command TrqRefO from the driver's cab and the torque reduction amount TrqZEN
Then, a new torque command TrqRef1 is obtained by equation (8) and output.

[0026]

(7) TrqRef1 = TrqRefO- △ TrqZEN (8) Then, based on the torque command TrqRef1, torque control of the electric motor whose rotational speed in the vehicle 1 is ωr1 is performed.

That is, when the all-axis idle occurs, all the rotation speeds detected by the wheel speed detection unit 2 tend to increase. Therefore, the vehicle speed ωrT estimated by the vehicle speed estimation unit 31 also increases. However, immediately before the all-axis idling occurs, the vehicle speed estimating unit 31 determines the vehicle speed ωrT
The minimum wheel speed increase rate used in estimating the wheel speed is low (the minimum axis has not yet reached idling), so the idling speed Δωr (deviation from the vehicle body speed) calculated by the idling speed calculating unit 32 increases. I do. If the axis used when estimating the vehicle speed ωrT by the vehicle speed estimating unit 31 reaches idle, the vehicle speed ωrT estimated by the vehicle speed estimating unit 31 also increases, as described above. The idling speed △ ωr (deviation from the vehicle speed) calculated at 32 is constant. As described above, the signs of the occurrence of the all-axis idling include an increase in the idling speed △ ωr, and the continued rotation of the idling speed △ ωr in the increased state.
In No. 3, when the slip speed △ ωr continuously exceeds a predetermined reference slip speed △ ωrset for a predetermined time Tset or more, it is determined that all the axes are spinning (a precursor to the occurrence of all-axis slip). Then, control for reducing the torque is performed.

By performing such control, control for suppressing all-axis idling based on a signal from a speed sensor generally mounted for controlling an induction motor without mounting a special vehicle speed sensor is provided. It can be carried out.

FIG. 5 is a configuration diagram of an electric vehicle control device according to a second embodiment of the present invention. Although only one vehicle is shown in the drawing, the electric vehicle is configured by connecting a plurality of such vehicles.

The vehicle 1 is provided with a wheel speed detecting unit 2 for detecting a rotating speed of an electric motor connected to the wheels, and the rotational speed detected by the wheel speed detecting unit 2 (the electric motor is provided on each shaft). Ωr1 to ωr4 are input to the control unit 4.

The control unit 4 comprises a vehicle speed estimating unit 41, idling speed calculating units 421 to 424, an all-axis idling detecting unit 43, and an all-axis idling suppressing torque narrowing unit 441 to 444. Here, the vehicle speed estimating unit 41 and the idling speed calculating units 421 to 4
24, the all-axis anti-spin torque reduction units 441 to 444 have the same configurations as the vehicle body speed estimation unit 31, the anti-spin speed calculation unit 32, and the all-axis anti-spin torque reduction units 34 shown in the first embodiment of FIG. 1, respectively. Therefore, the description is omitted here.

The all-axis idling detecting section 43 has a configuration shown in FIG. 6 and includes a minimum value selecting section 431, a subtracting section 432, and a comparing section 43.
And 3, a rise delay section 434. The minimum value selector 431 receives the respective slip speeds △ ωr1 to △ ωr4 calculated by the slip speed calculators 421 to 424, selects and outputs the minimum slip speed △ ωrMin. Subtraction unit 432
Calculates the deviation between the slip speed △ ωrMin and a predetermined reference slip speed △ ωrset, and outputs the calculated difference to the comparing unit 433. The comparison unit 433 outputs the flag FlgZENO based on the determination of the expressions (9) and (10).

[0033]

(8) When ΔωrMin−Δωrset ≦ 0 FlgZENO = 0 (9) When ΔωrMin−Δωrset> 0 FlgZENO = 1 (10) When the flag FlgZENO is input, the flag Flg
When ZENO = 1 is continuously input for a predetermined time Tset or longer, the detection flag FlgZEN = 1 is output. Otherwise, the detection flag FlgZEN =
Outputs 0.

By performing such control, it is possible to suppress the operation of detecting the idle rotation of all the shafts and reducing the useless torque even though all the shafts are not idle, as compared with the first embodiment.

FIG. 7 is a configuration diagram of an electric vehicle control device according to a third embodiment of the present invention. Although only one vehicle is shown in the drawing, the electric vehicle is configured by connecting a plurality of such vehicles.

The vehicle 1 is provided with a wheel speed detecting unit 2 for detecting a rotating speed of an electric motor connected to wheels, and the rotational speed detected by the wheel speed detecting unit 2 (motors are provided on respective shafts). Ωr1 to ωr4 are input to the control unit 5.

The control unit 5 includes a vehicle speed estimating unit 51, an idling speed calculating units 521 to 524, an all-axis idling detecting unit 53, a reference axis discriminating unit 54, and an all-axis idling suppressing torque throttle unit 55. Here, the vehicle speed estimating unit 51 and the idling speed calculating unit 5
21 to 524 and the all-axis idling detecting unit 53 have the same configuration as the vehicle body speed estimating unit 41, the idling speed calculating units 421 to 424, and the all-axis idling detecting unit 43 shown in the second embodiment of FIG. 5, respectively. Here, the description is omitted.

The reference axis discriminating section 54 includes an idling speed calculating section 52
The idle speeds △ ωr1 to △ ωr4 calculated in 1 to 524
Is input, and the reference axis signal N
Output umb.

[0039]

Num = 1 in the case of ΔωrMin = △ ωr1 (11) Num = 2 in the case of ΔωrMin = △ ωr2 Num = 2 (12) In the case of ωr4, Numb = 4 (14) The all-axis idling suppressing torque restrictor 55 sets the detection flag FlgZ
EN, reference axis signal Numb, and torque command T from the cab
rqRefO is input, and the torque command of each axis is calculated and output according to equations (15) to (18).

[0040]

Equation 10] For Numb = 1 TrqRef1 = TrqRefO- △ TrqZEN TrqRef2 = TrqRefO (15) TrqRef3 = TrqRefO TrqRef4 = TrqRefO Numb = 2 when TrqRef1 = TrqRefO TrqRef2 = TrqRefO- △ TrqZEN (16) TrqRef3 = TrqRefO TrqRef4 = TrqRefO Numb = 3 when _{TrqRef1 = TrqRefO TrqRef2 = TrqRefO (17} ) TrqRef3 = TrqRefO- △ TrqZEN TrqRef4 = TrqRefO Numb = 4 when _{TrqRef1 = TrqRefO TrqRef2 = TrqRefO (18} ) TrqRef3 = TrqRefO TrqRef4 = TrqRefO- △ TrqZEN like this braking By performing the above, an axis having a low idling speed capable of easily eliminating all-axis idling can be specified as an axis for which torque should be reduced as compared with the second embodiment. Shaft idling can be suppressed.

FIG. 8 is a configuration diagram of an electric vehicle control device according to a fourth embodiment of the present invention. Although only one vehicle is shown in the drawing, the electric vehicle is configured by connecting a plurality of such vehicles.

The vehicle 1 is provided with a wheel speed detecting unit 2 for detecting a rotating speed of a motor connected to wheels, and the rotational speed detected by the wheel speed detecting unit 2 (motors are provided for each shaft). Ωr1 to ωr4 are input to the control unit 6.

The control unit 6 includes a vehicle speed estimating unit 61, idle speed calculating units 621 to 624, and all-axis idle detecting units 631 to 63.
4. It is composed of an all-axis idling suppressing torque throttle section 64. Here, the vehicle speed estimating unit 61, the idling speed calculating units 621 to 6
24, the all-axis idling detection units 631 to 634 are respectively shown in FIG.
It has the same configuration as the vehicle body speed estimating unit 31, the idling speed calculating unit 32, and the all-axis idling detecting unit 33 shown in the first embodiment, and a description thereof will be omitted.

The all-axis idling suppressing torque restricting section 64 inputs the detection flags FlgZEN1 to FlgZEN4 of each axis,
A torque command for each axis is calculated and output according to equations (19) to (22).

[0045]

[Number 11] In the case of FlgZEN1 = 1 TrqRef1 = TrqRefO- △ TrqZEN TrqRef2 = TrqRefO (19) TrqRef3 = TrqRefO TrqRef4 = TrqRefO FlgZEN2 = 1 if TrqRef1 = TrqRefO TrqRef2 = TrqRefO- △ TrqZEN (20) TrqRef3 = TrqRefO TrqRef4 = TrqRefO FlgZEN3 = 1 if _{TrqRef1 = TrqRefO TrqRef2 = TrqRefO (21} ) TrqRef3 = TrqRefO- △ TrqZEN TrqRef4 = TrqRefO FlgZEN4 = 1 if _{TrqRef1 = TrqRefO TrqRef2 = TrqRefO (22} ) TrqRef3 = TrqRefO TrqRef4 = TrqRefO- △ T rqZEN That is, control is performed to reduce the torque of only the one whose detection flag is 1. Here, the detection flags FlgZEN1, F
The operation when lgZEN2 becomes 1 at the same time will be described with reference to FIG. In the case where all-axis idling is simultaneously detected in the 1-axis and the 2-axis, when the detection flag FlgZEN1 = 1, the 1-axis side starts the torque reduction amount ΔTrqZEN1 in a step-like manner from 0, and sets 0 at a constant reduction rate. To reduce. Then, a new torque command Tr is obtained from the torque command TrqRefO from the driver's cab and the torque throttle amount △ TrqZEN1.
qRef1 to TrqRef4 are obtained by equation (19) and output. On the other hand, the detection flag FlgZEN2 =
As soon as it becomes 1, the torque reduction amount △ TrqZEN2
Do not start in steps from 0, and after a certain time,
The torque reduction amount ΔTrqZEN2 is raised in steps from 0, and is reduced to 0 at a constant reduction rate. Then, based on the torque command TrqRefO from the driver's cab and the torque reduction amount △ TrqZEN2, a new torque command TrqRe
f is obtained by equation (20) and output.

By performing such control, the torque throttle control when the all-axis idle is detected can be time-dispersed in the vehicle, and the all-axis idle can be suppressed without deteriorating the riding comfort.

[0047]

As described above, according to the present invention, it is possible to provide an electric vehicle control device capable of performing idle control reliably even in a state in which all axes idle.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an electric vehicle control device according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a vehicle body speed estimation unit in FIG. 1;

FIG. 3 is a configuration diagram of an all-axis idling detection unit in FIG. 1;

FIG. 4 is an explanatory diagram of torque throttle control.

FIG. 5 is a configuration diagram of an electric vehicle control device according to a second embodiment of the present invention.

FIG. 6 is a configuration diagram of an all-axis idling detection unit in FIG. 5;

FIG. 7 is a configuration diagram of an electric vehicle control device according to a third embodiment of the present invention.

FIG. 8 is a configuration diagram of an electric vehicle control device according to a fourth embodiment of the present invention.

FIG. 9 is an explanatory diagram of torque throttle control.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Vehicle 2 ... Wheel speed detection part 3,4,5,6 ... Control part 31,41,51 ... Vehicle speed estimation part 32 ... Slip speed calculation part 33,43,53 ... All axis slip detection part 34,55, Reference numeral 64: all-axis idling suppressing torque throttle unit 54: reference axis discriminating unit 311: selecting unit 312: differentiating unit 313: vehicle acceleration estimating unit 314: adding unit 315: integrating unit 316, 331, 432: subtracting unit 317: steady-state deviation correction Units 332, 433 Comparison unit 333, 434 Rise delay unit 421, 422, 423, 424 Slip speed calculation unit 441, 442, 443, 444 All-axis idling suppression torque throttle unit 431 ... Minimum value selection unit 521, 522 , 523, 524: idling speed calculating unit 621, 622, 623, 624: idling speed calculating unit 631, 632, 633, 634: all-axis idling detecting unit

Claims (7)

[Claims] 1. A plurality of wheel speed detecting means provided in a plurality of vehicles constituting an electric vehicle, each detecting a rotational speed of an electric motor connected to a wheel, and the wheel speed detecting device provided in the same vehicle. Vehicle speed estimating means for estimating the vehicle speed of the electric vehicle based on the rotational speed detected by one or more wheel speed detecting means of the means; provided for each wheel speed detecting means; A plurality of idling speed calculating means for calculating the idling speed based on the rotational speed detected by its own wheel speed detecting means; provided for each of the wheel speed detecting means, corresponding to its own wheel speed detecting means Based on the idling speed calculated by the idling speed calculating means, the precursor of all the wheels corresponding to the one or more wheel speed detecting means used for estimating the vehicle speed is indicated. A plurality of all-axis idling detection means for detecting, provided for each of the wheel speed detection means, when the precursor of the idling is detected by the all-axis idling detection means corresponding to the own wheel speed detection means, the own wheel is detected. An electric vehicle control device, comprising: a plurality of torque reduction means for reducing the torque of the electric motor detected by the speed detection means. 2. The electric vehicle control device according to claim 1, wherein said all-axis idling detecting means is provided when said idling speed continuously exceeds a predetermined reference idling speed for a predetermined time or more. An electric vehicle control device characterized by detecting a sign of idling. 3. A plurality of wheel speed detecting means provided in a plurality of vehicles constituting an electric vehicle, each detecting a rotational speed of an electric motor connected to wheels, and the wheel speed detecting device provided in the same vehicle. Vehicle speed estimating means for estimating the vehicle speed of the electric vehicle based on the rotational speed detected by one or more wheel speed detecting means of the means; and the wheel speed provided on the same vehicle as the vehicle speed Two or more idling speed calculating means for calculating an idling speed for each of the two or more wheel speed detecting means based on each rotational speed detected by two or more wheel speed detecting means among the detecting means; On the basis of the idling speed calculated by the idling speed calculating means, a precursor to all the wheels corresponding to the one or more wheel speed detecting means used for estimating the vehicle body speed is given. An electric motor comprising: an all-axis idling detecting means for detecting; and, when the all-axis idling detecting means detects a sign of idling, torque reducing means for reducing a torque of an electric motor connected to a wheel where the sign of idling is detected. Car control device. 4. The electric vehicle control device according to claim 3, wherein the all-axis idling detection means determines in advance that the minimum value of the absolute value of the idling speeds calculated by the two or more idling speed calculating means is predetermined. An electric vehicle control device characterized by detecting a sign of idling when a predetermined reference idling speed is continuously exceeded for a predetermined time or more. 5. A plurality of wheel speed detecting means provided in a plurality of vehicles constituting an electric vehicle, each detecting a rotational speed of an electric motor connected to a wheel, and the wheel speed detecting means provided in the same vehicle. Vehicle speed estimating means for estimating the vehicle speed of the electric vehicle based on the rotational speed detected by at least one of the wheel speed detecting means; and the vehicle speed and the wheel speed detection provided on the same vehicle. Two or more slip speed calculating means for calculating a slip speed for each of the two or more wheel speed detecting means based on each rotational speed detected by two or more wheel speed detecting means among the means, On the basis of the idling speed calculated by the idling speed calculating means, a precursor to all the wheels corresponding to the one or more wheel speed detecting means used for estimating the vehicle speed is detected. The all-axis idle detection means and the wheel speed detection means whose absolute value is the minimum of the idle speeds calculated by the idle speed calculation means when the precursor of the idle rotation is detected by the all-axis idle detection means. An electric vehicle control device comprising: torque reduction means for reducing torque of an electric motor connected to a corresponding wheel. 6. The electric vehicle control device according to claim 1, wherein when a plurality of all-axis idling detecting means simultaneously detect a precursor of the idling, the plurality of torque reducing means controls the torque reduction of the electric motor. An electric vehicle control device characterized by being shifted. 7. The electric vehicle control device according to claim 1, wherein said vehicle speed estimating means includes a rotation detected by two or more wheel speed detecting means provided on the same vehicle. An electric vehicle control device, wherein the vehicle body speed is estimated based on a minimum value during power running of the electric vehicle and a maximum value during regeneration of the electric vehicle.