JPS5915242B2 - Railway vehicle control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a railway vehicle control device for controlling idling or sliding of a railway vehicle.

It is well known that in a railway vehicle (hereinafter referred to as a vehicle), if its driving force or braking force exceeds the adhesion limit determined by the coefficient of friction between the rail and the wheels, it will skid or skid.

Since these two phenomena are essentially the same, similar measures can be considered as countermeasures.

Therefore, the following explanation will focus on the operation during rolling, that is, mainly on idling, but if there are any particular differences during braking, they will also be explained.

The conventional device and the embodiments of the present invention will be explained using an electric vehicle as an example.

Recently, due to the need for mass, high-speed transportation of freight cars, the driving wheels of locomotives and
It has become necessary to utilize the adhesive force between the rails as effectively as possible as a tensile force.

One method is to provide a voltage control device for each main motor for driving the wheels.

FIG. 1 shows the main circuit of a rectifier-type AC electric car, which has two main motors, as an example of such an electric car.

In the figure, P is the pantograph, MT is the main transformer, ■R1
, ■R2 indicates a voltage control device that receives and rectifies the output of the main transformer MT, and is composed of, for example, Cyrisk, and performs phase control of the voltage. For cars, there are non-arc tap changers, and for DC electric cars, there are cyrisk choppers, etc.

Mt 2M2 is the main motor that drives the first and second shafts, AMl and AM2 are the armatures of the main motors, Fl and F.
2 shows the series field winding of each main motor.

DCLl. DCL2 indicates a smoothing reactor inserted into each main motor circuit in order to smooth the main motor current which pulsates due to the above-described phase control.

The traction motor M1 is connected to the output side of the voltage control device VR1 to form one group (this will be referred to as the first group), and the traction motor M2
is connected to the output side of the voltage control device vR2 and is connected to another group (
This is called the second group).

Further, APPS, , APPS2 indicate phase shifters, and when the inputs of the adders C1 and C2 become large, the output voltage Er1. The control angle of the thyristor etc. is controlled as Er2 increases,
Epl, Epi′! , voltage command value, Ef, , Ef
2 is a feedback signal generated by idle rotation, which will be described later.
, by F2p2-Ef2, the second group of phase shifters APP
It controls S2.

In addition, in electric vehicles that perform regenerative braking, a device that can transmit and convert is used as a voltage control device, and the braking current is controlled by changing the power supply voltage seen from between the main motor circuit terminals. In this case, the power supply side can be seen as a load to the main motor operating as a generator.

As a control system for suppressing wheel slip, the one shown in FIG. 2 is known.

In Figure 2, in order to detect the wheel circumferential speeds of the first and second axles of PG, PC, &, respectively, the speed generators, vl and F2, installed on the first and second axles are used to generate speed generators, respectively. machine, PGl, PC
2, which is a signal proportional to the circumferential speed of the wheels of the first and second axles, PGo is a speed generator attached to a driven shaft (not shown) to detect the actual speed (traveling speed) of the vehicle, and VT is the speed The output of the generator PGo is a signal proportional to the actual speed of the vehicle, and the adders C3 and C4 output outputs v1-vt and v2-vt, respectively, which are proportional to the relative speed, and the outputs V, -vt.

When F2-Vj is greater than the relative speed dead band value △v1, the amplifiers A, , A2 are set to V1sV2 to v, -Vt-, respectively.
Outputs an output proportional to Vj-△v1, and the output becomes the command value E
p12Ep2 and the phase shifters APPS, APP
S.

The output voltage of the voltage control devices VR, , VR2 decreases.

The dead zone value △■1 will be described later.

Furthermore, in the differentiator, ,D2, the wheel circumferential speed v
1. When the time differential value of v2 is output, and the output value, ÷2, is equal to the acceleration dead band value, the amplifier A3,
A4 are respectively registers -△α.

↓It outputs an output proportional to 2-Δα, and the output corresponds to each command value Ep1. Ep2 and phase shifter APPS1APP
The output of S2 decreases and the voltage controller VR,.

The output voltage of VR2 decreases.

Δα is set to a value equivalent to the maximum value of the driving wheel circumferential acceleration during normal operation.

In this way, the relative velocity feedback system and the wheel circumferential acceleration feedback system are provided in parallel, and any feedback signal generated is fed back, and the sum of the outputs of amplifiers A and A3 is The sum of the output of amplifier A2 and the output of amplifier A4 is the feedback signal Ef1 of FIG. 1, and the feedback signal Ef2 of FIG.
corresponds to

Therefore, now the first axis is idling and the relative speed V1-
When vt becomes smaller than the dead band value △v1, the output voltage Er1 of the voltage control device VR1 of the first group decreases, and the main motor M
The current of the first shaft is forcibly reduced, that is, the driving torque of the first shaft is forcibly reduced, and idling is suppressed.

In addition, when the wheel circumferential acceleration v1 exceeds the dead zone value △α, such as when driving into a place covered with oil, the output voltage Er1 of the voltage control device decreases and the drive torque of the first axis decreases. It is forcibly reduced and idling is suppressed.

When suppressing skidding during braking, the wheel peripheral speed of the sliding shaft decreases from the actual speed of the vehicle, contrary to the case of slipping when moving, so the inputs of adders C3, C4, C7°C8 are The polarity is opposite to that in Figure 2.

It is known that the relationship between the slip rate and the linear force between the wheels and the rails during slipping or skidding is as shown in Figure 3.

Here, the slip rate is l v - vt I, where V is the wheel circumferential speed of the spinning or sliding shaft and vt is the actual speed of the vehicle.
/vt, and the tangential force between the wheel and rail (hereinafter abbreviated as tangential force) is the traction force generated by the shaft.

As shown in Figure 3, region A (called the micro-slip region) where the tangential force increases as the slip rate increases, and region B (called the macro-slip region) where the tangential force decreases as the slip ratio increases. Region A is a stable region, and in order to obtain high tangential force, it is better to have a high sliding speed in region A, but in region B, as the sliding speed increases, the tangential force decreases. The frictional force between the wheels and the rails becomes a negative resistance, which may generate self-excited vibrations in the drive shaft system, resulting in excessive stress. Therefore, it is desirable that the sliding speed be low in this region.

From the above, in order to make maximum use of the adhesive force between the wheels and the rails, it is necessary to give each wheel a slip rate that maximizes the tangential force.

Since the coefficient of friction is the tangential force on the vertical axis divided by the vertical load, that is, the axle load, it can be considered that the coefficient of friction has the characteristics as shown in FIG.

The relationship between the slip rate and the tangential force varies depending on the condition of the rail and wheel surface, and it is generally known that the smaller the maximum value of the tangential force, the greater the slip rate at which the tangential force becomes maximum.

Therefore, the relationship between the slip rate and tangential force of each axis is naturally slightly different (see the following document).

Literature (1) R8Zwah, 5en, Baden, and W
,U.

Bohti, Ziirich: Design Conc.
eptof Etectronic Control
A System+for Traction Veh
ictes with Phase-Angle Con
'tra/S:BrqwnBoveri Revie
wl 2 (1975) In Figure 4, al is the relationship between the slip rate of the first axis and the tangential force at a certain moment, C2 is the relationship between the slip rate of the second axis and the tangential force at that time, and C3 is the location where the friction coefficient is small. This figure shows an example of the relationship between slip rate and tangential force.

For the sake of simplicity, assume that the voltage command values "'pt z" T)2 for both groups are equal, and that the wheel circumferential driving forces of the first and second axles are equal and as shown in Figure 4. The slip rate is C
1. The slip rate of the second axis is C2.

The dead zone value △v1 in Fig. 2 is provided to cause slippage in the microslip region, and if △v1 is set to a value equivalent to the slip rate ε' of the total 1w figure, then the al line For line C2, a feedback signal due to relative velocity in the microslip region is not generated due to ε and <ε′, but a feedback signal due to relative velocity is generated due to the relative velocity due to C2〉ε′ even though it is in the microslip region. Since the output voltage of the voltage control device is reduced and the driving torque is forcibly reduced, only the tangential force corresponding to the slip rate ε' can be used.

If, for example, the first shaft enters the position of line C3 while powering in the state of line S in Figure 4, the circumferential acceleration v1 of the first shaft becomes abnormally large, and even though it is in the micro-slip region, the acceleration Since a feedback signal is generated and the output voltage Er1 of the voltage control device vR1 is decreased, the slip rate of the first axis becomes a very small value.

As described above, in the known example shown in FIG. 2, there are many cases where the maximum value of the tangential force cannot be utilized.

FIG. 5 shows another known example of the slip suppression control system. Since it does not have a driven shaft, the speed generator output v7 of the first and second shafts is detected by the minimum value detection device MIN. It is exactly the same as in FIG. 2 except that the smaller value of v2 is detected and the detected value Vmin is used in place of the actual speed vtO in FIG.

Vmi if at least one axis is in the microslip region
Since n can be approximately regarded as vt, the idling suppression operation is performed by the same operation as shown in FIG.

Now, suppose that the voltage command values Ep1. for the first group and the second group. Ep
2 are equal, the wheel circumferential driving forces of the first and second axles are as shown in Figure 4, and the relationship between the slip ratio of the first shaft and the tangential force is shown by line C1 in Figure 4, and the slip ratio of the second shaft. Assuming that the relationship between
The slip rate of the shaft is C2.

Since the slip rate of each axis is usually different, the dead zone △v corresponding to a slip rate that is smaller than that shown in Fig. 4 ε'
By providing Δv1, it is possible to cause each axis to slip in the micro-slip region, and a higher tangential force can be obtained than when Δv1 is not provided.

However, in the case of FIG. 5, the maximum value of the tangential force cannot always be utilized for the same reason as the case of FIG. 2.

Furthermore, the case shown in FIG. 5 also has the disadvantage that the idling of one group also affects other groups.

In other words, while the car is moving with the wheel circumferential driving force shown in Figure 4, the first
If the axis enters the position of the C3 line, the acceleration will be abnormally large, and the feedback signal due to the acceleration ÷ 1 -
The output voltage Er1 of the stain pressure control device VR1 is greatly reduced by Δα, and becomes ε1==0.

As a result, the relative speed V2-Vmin of the second axis increases and v
2-vm row ≧△v1, the output voltage Er2 of the voltage control device of the second group is decreased, and the second group that is not idling is
The drive torque of the shaft is also reduced.

In this way, the fact that the driving torque of the healthy shaft also decreases due to the influence of the idle rotation of the other shafts means that the meaning of dividing the main motor circuit into a plurality of groups is lost.

Such a phenomenon is likely to occur even when the acceleration feedback system is not provided in FIG. 5 and only the relative velocity feedback system is used, especially when the main circuit is composed of three or more groups.

SUMMARY OF THE INVENTION An object of the present invention is to provide a railway vehicle control device that does not have the above-mentioned drawbacks and can utilize the adhesion force of each axis to the maximum extent possible.

The present invention provides means for detecting the actual vehicle speed or a value equivalent to the actual speed, means for detecting the wheel circumferential speed of the drive shaft or braking shaft of the vehicle, means for determining the differential value of the wheel circumferential speed, and means for determining the relative speed between the actual speed and the wheel peripheral speed; when the relative speed is greater than a predetermined level and the differential value is greater than a predetermined level, the driving torque or braking torque of the relevant shaft is forcibly reduced; The first feature is that the comparison level for the relative speed is changed depending on the actual speed, and the differential value of the minimum value of the wheel circumferential speed of the drive shaft or the differential value of the maximum value of the wheel circumferential speed of the brake shaft. , and when the value is higher than a predetermined level, the driving torque or braking torque of all axes is forcibly reduced, and furthermore, when the relative speed is higher than a second comparison level, the driving torque or braking torque is Its features include the addition of a system that forcibly reduces braking torque.

FIG. 6 shows a slip suppression control system of an embodiment in which the present invention is applied to an electric vehicle with a main circuit as shown in FIG.
As in the figure, the minimum value of the wheel circumferential speed of each axis is used instead of the actual speed.

Components labeled with the same symbols as in FIG. 5 are as explained above, and therefore their explanation will be omitted.

One of the differences from FIG. 5 is an AND circuit AND1. AND2 is provided, and the output of the AND circuit causes the analog switches S1 . S2 is turned on, and the acceleration feedback signal is then sent to the adders C1 and C.
The point is that the system is configured so that input is performed in step 2.

That is, when the relative speed is greater than a predetermined level and the wheel circumferential acceleration is greater than a predetermined level, the acceleration feedback signal is fed back to reduce the output voltage of the voltage control device.

Therefore, in the micro-slip region, even if the relative speed of the shaft becomes larger than the predetermined dead band value △v1, no feedback is given unless the wheel circumferential acceleration is greater than a predetermined level, and the wheel circumferential acceleration enters the macro-slip region and reaches the predetermined value. When the velocity exceeds the level, an acceleration feedback signal is fed back to control the slip velocity in the macro slip region to be as small as possible.

Furthermore, even if the first axis enters a place with a low friction coefficient such as the C3 line while moving in the above-mentioned state shown in Fig. 4, the acceleration feedback signal is not immediately fed back and the main According to the characteristics of the electric motor, the slip speed in the micro-slip region increases and the relative speed v1-■min becomes △V, which is a dog. If the wheel circumferential acceleration is more dog than △α, the acceleration feedback signal is fed back. .

In this way, by selecting appropriate values for the dead zone values △v1 and △α, the slip speed in the micro-slip region is large, and the slip speed in the macro-slip region is minimized by /J.
This makes it possible to control the temperature so that it becomes smaller.

Also, due to idle rotation of other axes, the relative speed temporarily decreases to the dead zone value △v
1. Even if the wheel circumferential acceleration of the sound shaft exceeds the dead zone value Δα, there will be no feedback, so the sound shaft will not be affected by the slipping of other axles. It is worthless.

In addition to the above system, the output v1-vm of adder C3jC4
in, when v2-vmin is greater than △v2, amplifiers A5jA6 respectively provide vl-vmin-△v25 v2
A system is provided that outputs an output proportional to 'min-△V2 and uses this output to reduce the output voltage of the voltage control device.
This has the effect of preventing this from reaching the above level.

Furthermore, the output vmi of the minimum value detection device is
When n is differentiated and the differential value vmlo is greater than Δα, amplifier A7 outputs an output proportional to Vmin−Δα, which reduces the output voltages of both groups of voltage control devices.

Since Vmir is a value Δα corresponding to normal operation, it can be assumed that both the first and second axes are idling when the vehicle is a dog, so this system has the effect of preventing all axes from idling.

Although FIG. 6 shows the case where Vmin is used instead of the actual speed of the vehicle, it is of course possible to use the actual speed of the vehicle.
In this way, more ideal control can be achieved.

Further, a feedback system is not necessarily necessary when the relative velocity is greater than Δv2.

Further, the feedback system when vmin is larger than Δα is not necessarily necessary because the probability of all shafts idling is small when the number of main motors is large.

Furthermore, it is known that the slip rate at which the tangential force is maximum does not change much depending on the vehicle speed, that is, the slip rate at that time tends to increase as the vehicle speed increases, so the dead band value Δv1 with respect to the relative speed is It is desirable to increase with speed.

In addition, in the case of braking, in addition to the changes mentioned in the explanation of FIG. 2, the polarity of the input to the adder C1l may be reversed.
As a result, exactly the same effect as in the case of Ka row can be obtained.

FIG. 7 shows an example of an electric vehicle in which four main motors are driven by one voltage control device, and the speed of the driven shaft is used as the vehicle speed.

Similar elements to those in FIGS. 2 and 5 are given similar symbols.

PGl, PO2, PO2, PO2 are 1°2.3, 4 respectively
This is a speed generator attached to the 1.2 and 3.4 shafts to detect the wheel peripheral speed of the shaft (the shaft driven by the main motor M12M22M32M4), and Vl 3 V22 V35
VL is the speed generator PG1゜PO2, PO2, PO
2, and is a signal proportional to the circumferential speed of the wheels on the 2° and 3.4 axes.

PGo is a speed generator attached to the driven shaft for detecting the actual speed of the vehicle, and its output Vt is a signal proportional to the actual speed of the vehicle.

Dl, D2. D3 and D4 are the speed generator output V1, respectively.
y V2, V33 Differentiator to find the differential value of V4, r
l, r2. r3. r4 is the differentiator D1. D2. D
3. Diode for detecting the maximum value of the output of D4, r5,
r65 r7, rB is the speed generator output v1. v2
．． v3. This is a diode for detecting the maximum value of v4.

As shown in the diagram, the wheel circumferential speed of each driving wheel axle V12 V23 V
35 Maximum value vmax of V4 and wheel circumferential speed vt of driven shaft
0 difference is larger than a predetermined level Δv1, and the differential value of the wheel circumferential speed is greater than a predetermined level Δv1.

÷2. When the maximum value VmaX of ÷241"35 V is larger than the predetermined level Δα, the AND circuit M outputs an output, turns on the analog switch S, and V(71az lh
A signal proportional to α is input to adder C1, and the output of voltage controller VR is decreased.

The reason why the maximum relative speed end a>(Vt and the maximum wheel circumferential acceleration "max" are used in this way is for simplification.

As mentioned above, the sliding speed at which the tangential force is maximum varies depending on the condition of the rail surface and inherently has variations, so it is considered that there is no significant difference in effectiveness even if the maximum relative speed is used.

Furthermore, when the maximum relative speed exceeds a predetermined level and the maximum wheel circumferential acceleration exceeds a predetermined level, the shaft is usually considered to be in the macro slip region.
A feedback signal based on the maximum wheel circumferential acceleration is fed back.

In addition to the above feedback system, the maximum relative velocity vma
When X-v2 is a dog from the second dead zone △v2, the maximum relative speed signal is fed back to prevent excessive slipping due to minute acceleration, and the minimum wheel circumferential speed Vmin is detected by the minimum value detection device MI.
N, and the detected value Vmin is differentiated by a differentiator D5,
When the differentiator output vmin is smaller than the dead zone value Δα, a feedback signal based on the maximum wheel circumferential acceleration VHin is fed back to prevent all axes from spinning.

In this embodiment, the output of the analog switch S, the amplifier A3
The sum of the output of the amplifier A4 and the output of the amplifier A4 is the feedback signal F2f due to the idle rotation.

In addition to the above-mentioned embodiments, according to the present invention, as shown in FIG. 6, it is possible to reduce the output of the voltage control device using only the outputs of the differentiators D1 and D2, thereby preventing idling.

In other words, in the macro slip region, as mentioned above, as the slip rate increases, the tangential force decreases, and in order to prevent macro slip, it is necessary to reduce the drive torque generated by the traction motor to below this tangential force. be.

On the other hand, the differential value of the wheel circumferential speed of the driving wheel shaft that is experiencing macro slip is large at the beginning of macro slip occurrence and becomes zero at the maximum slip speed.

Therefore, the feedback signal Ef is large at the beginning of macro slip occurrence and becomes zero at the maximum slip speed.

However, as shown in FIG. 1, the main motor circuit includes a smoothing reactor DCL1. DCL2. The smoothing reactor and main motor winding inductance and voltage control device V
Because of the delay elements of R1 and VB2, the traction motor current lags behind the feedback signal, so amplifier A3. By appropriately selecting the gain of A4, the torque generated by the main motor can be sufficiently reduced to the point where the slip rate is maximum, and macro slip can be prevented.

In other words, the motor current lags behind the command to the voltage control device due to the effect of the delay element described above, so if you differentiate the slip speed and narrow down the voltage command with the output early, the slip will be reduced. The motor current is throttled in proportion to the increase in speed, making it possible to prevent slippage at just the right time.

Examples based on this viewpoint are shown in FIGS. 8 and 9.

FIG. 8 corresponds to the embodiment of FIG. 6, and the adder C
The input to 1 is the output of switch S1 and the command value ""pt
, the inputs to the adder C2 are only the output of the switch S2 and the command value Ep2.

FIG. 9 shows an embodiment of the conventional example shown in FIG. 2, in which switches S, S2 are opened and closed by the outputs of AND gates AND1 and AND2, and adders C1 and C2 have the same configuration as in FIG. It has become.

The functions and effects of the embodiments shown in FIGS. 8 and 9 have been described above and will therefore be omitted.

FIG. 10 shows another embodiment of the invention.

This embodiment is characterized by the amplifier A1. Switch the output of A2'
Tutsi S3. The reason is that the signal is applied to adders C1 and C2 via S4.

Furthermore, switch S3. S4 is an AND gate AND1. A
It is opened and closed by the output of ND2.

According to this embodiment, switch S3. By adding the loop S4, the relative velocity is greater than Δv1,
When the differential value of the wheel circumferential speed of each axis is greater than Δα, a relative speed signal is also fed back in addition to the differential value signal.

In this way, even when the inductance of the traction motor circuit and the delay of the voltage control device are small, a sufficiently large feedback signal can be obtained up to the point where the slip speed, that is, the relative speed is maximum, and macro slip can be prevented. was able to obtain.

The above example takes an electric car as an example and shows an example of reducing the output voltage of the voltage control device as a method of forcibly reducing the driving torque or braking torque.
The main motor field current can be controlled by the feedback signal Ef caused by slipping or skidding, and a solenoid valve or a relay can be operated to perform various slipping or skidding suppressing operations.

Further, although an embodiment using a series-wound motor has been shown, a compound-wound motor or a completely separately excited motor may of course be used, and there is no restriction on the number of main motors in series or parallel.

Furthermore, although we have explained the case where a speed generator is used as the speed detection device, since the difference in traction motor voltage is approximately proportional to the wheel circumferential speed difference, the speed generator PG is used as the traction motor voltage detection device. Even if B is changed, almost the same effect as the device of the present invention can be obtained.

The above description has been about electric vehicles, but for vehicles that use a diesel engine as the prime mover, a feedback signal from the above-mentioned idling can be used to operate a solenoid valve or a relay to control the fuel system of the engine to suppress the idling. It is also possible to

As detailed above, according to the present invention, it is possible to make maximum use of the adhesion force of each driving wheel axle, so the adhesion performance of a railway vehicle can be greatly improved, and a lightweight vehicle can transport a large amount of cargo at high speed. Transport is possible.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an example of the main circuit of an electric vehicle to which the present invention is applied, and FIG. 2 is an example of a known slip suppression control system for an electric vehicle having the main circuit of FIG. 1. A schematic configuration diagram, Fig. 3 is an explanatory diagram showing the relationship between the wheel slip rate and the line between the wheel tracks, Fig. 4 is a diagram showing an example of the slip rate of each axis and the line between the wheel tracks, and Fig. 5 is an explanatory diagram showing the relationship between the wheel slip rate and the line between the wheel tracks. FIG. 1 is a schematic configuration diagram showing another known example of a slip suppression control system for an electric vehicle having the main circuit shown in FIG. 1, and FIG. 6 is a schematic diagram showing an example of the control device of the present invention for an electric vehicle having the main circuit shown in FIG. 7 is a schematic diagram showing an example of the control device of the present invention for an electric vehicle in which four main motors are controlled by one voltage control device; FIG. 8, FIG. 9, and FIG. It is another example figure of. Ml, M2, M3, M4... Main motor, VRl
. VR2, VR, , voltage control device, APPSl, APP
S2゜APPS3...phase shifter, Dl 5 D2 5
D3 s D4. D5...Differentiator, MEN...Minimum value detection device, AN
D. AND2. AND...and gate.

Claims (1)

[Claims] 1. Means for detecting the speed of a railway vehicle, means for detecting a circumferential speed of the wheels of the vehicle, means for determining a change value in the circumferential speed of the vehicle, and means for detecting the speed of the vehicle and the circumferential speed of the wheels. and means for forcibly reducing the driving torque or braking torque when the relative speed is greater than a predetermined level and the change value of the wheel peripheral speed is greater than the predetermined level. A railway vehicle control device consisting of: 2. A railway vehicle control device according to claim 1, in which the speed of a railway vehicle is detected by setting the lowest value of the circumferential speed of the wheels of the drive shaft of the vehicle as the detected value. 3. A railway vehicle control device that detects the speed of a railway vehicle as set forth in claim 1 by setting the maximum value of the circumferential speed of the wheels of the brake shaft of the vehicle as the detected value. 4. Means for detecting the speed of the railway vehicle, means for detecting the circumferential speed of the wheels of the vehicle, means for determining the change value of the circumferential wheel speed, and determining the relative speed between the speed of the vehicle and the circumferential wheel speed. means for determining a dead zone value that changes depending on the speed of the vehicle; and means for forcing a driving torque or a braking torque when the relative speed is greater than the dead zone value and the change value of the wheel peripheral speed is greater than a predetermined level. A railway vehicle control device comprising means for reducing the 5. Means for detecting the speed of a railway vehicle, means for detecting the circumferential speed of a wheel of the drive shaft or brake shaft of the vehicle, means for determining a change value of the circumferential wheel speed, and the speed of the vehicle and the circumferential speed of the wheel. means for determining the relative speed between the drive shaft and the wheel circumferential speed, means for determining the change value in the minimum value of the circumferential speed of the wheel between the drive shaft and the wheel circumferential speed, or the change value in the maximum value of the wheel circumferential speed of the brake shaft; , and when the change value of the wheel circumferential speed is less than a predetermined level, and the change value of the minimum value of the wheel circumferential speed of the drive shaft or the change value of the maximum value of the wheel circumferential speed of the brake shaft is at a predetermined level. A railway vehicle control device comprising: means for forcibly reducing the driving torque of the drive shaft or the braking torque of the brake shaft when the vehicle speed is lower. 6 means for detecting the speed of the railway vehicle, means for detecting the circumferential speed of the wheels of the vehicle, means for determining the change value of the circumferential wheel speed, and determining the relative speed between the speed of the vehicle and the circumferential wheel speed. means for forcing a driving torque or a braking torque when the relative speed is larger than a first set level and the change value is larger than a predetermined level, and when the relative speed is larger than a second set level; A railway vehicle control device comprising means for reducing the