JP3132028B2 - Chassis dynamometer speed difference controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a simulated traveling system in which a predetermined speed difference is provided between wheels in order to simulate, for example, a situation in which some wheels of a vehicle have slipped in muddy ground. The present invention relates to a speed difference control device of a chassis dynamometer for performing a test.

[0002]

2. Description of the Related Art In general, a chassis dynamometer is provided with a roller which rotates against a wheel of a vehicle under test, a force for braking the rotation of the roller against a rotational force applied to the roller, or a roller for rotating the roller. By applying a force for positively rotating the vehicle, a load similar to the actual running state is applied to the wheels. Here, a rotating machine is used as a generator as a means for applying a force for braking the rotation against the rotating force given to the roller. On the other hand, a rotating machine is used as a motor as a means for positively applying a rotational force to the roller. For example, if the vehicle is accelerating, the rotating machine is used as a generator to provide resistance to the rotation of the rollers connected to the rotating machine. In addition, when the vehicle is decelerating, the rotating machine is used as a motor, and a force in a direction for positively rotating the roller connected to the rotating machine is applied. At this time, whether the rotating machine is used as a generator or a motor, the rotating machine has a total torque command value set to apply a load to the wheels of the vehicle under test according to the running state. It is driven based on. In such a chassis dynamometer, for example, when a roller that contacts the front wheel and a roller that contacts the rear wheel are driven at a predetermined speed difference, conventionally, the total torque command value is equally divided, and each of the equally divided torque values is conventionally used. Of the front wheel roller and the rear wheel roller are driven on the basis of the torque command value. If the speed difference between the rotation speed of the front wheel roller and the rotation speed of the rear wheel roller has a deviation with respect to the set value of the speed difference setting device, the rotating device for the front wheel roller or the rear wheel is adjusted to eliminate the deviation. Feedback control for correcting both torque command values of the wheel roller rotating machine is performed.

[0003]

However, according to the conventional speed difference control device, feedback control is performed in order to suppress fluctuation of the speed difference between the two rollers. However, from the viewpoint of control stability, the feedback gain is increased. The upper limit is naturally determined. For this reason, there is a problem with responsiveness,
It is difficult to control the speed difference between the two rollers while frequently changing the rotation speed of the two rollers. The technical problem of the present invention is that, while frequently changing the rotation speed of both rollers,
It is another object of the present invention to provide a chassis dynamometer speed difference control device capable of performing speed difference control satisfactorily.

[0004]

The above object is achieved by a speed difference control device for a chassis dynamometer according to the present invention, the structure of which is schematically shown in FIG. That is, the speed difference control device for the chassis dynamometer according to the present invention includes a first roller and a second roller that rotate while contacting each of a first wheel and a second wheel of the test vehicle; A first roller torque adjusting means B01 and a second roller torque adjusting means B02 for applying a rotational force to each roller or a force for braking the rotation against the rotational force applied to the roller, or applying a rotational force to each roller. A speed difference control device for performing a pseudo running test in a state in which the rotation speed difference between the first and second rollers is kept constant, wherein the first and second rollers are The first roller rotational acceleration calculating means B03 and the second roller rotational acceleration calculating means B04 which calculate the rotational accelerations of the first and second rollers by detecting the rotational speeds of the respective rollers and differentiating the rotational speeds.
A first roller rotation torque detection means B05 and a second roller rotation torque detection means B06 for detecting the rotation torque of each of the first and second rollers; a rotation torque value of the first roller; First wheel output calculating means B07 for calculating a rotational force applied by the first wheel of the test vehicle to the first roller from the rotational acceleration value; a rotational torque value of the second roller and a rotational acceleration of the second roller; A second wheel output calculating means B08 for calculating a rotational force applied by the second wheel of the test vehicle to the second roller from the value, and a difference between the first wheel output calculated value and the second wheel output calculated value. And a total torque instructing means B10 for instructing a total torque applied to the first roller and the second roller in order to apply a load to the test vehicle according to a running state. When, A wheel output difference correcting means B11 for subtracting the wheel output difference from the total torque command value by the total torque command means B10; and a torque command value obtained by equally dividing the torque command value after performing the wheel output difference correction. A first roller torque command means B12 for outputting a command value to the first roller torque adjusting means B01; and an output value of the first roller torque command means B12 subtracted from the total torque command value. And a second roller torque command means B13 for outputting the subtracted torque command value to the second roller torque adjustment means B02.

[0005]

According to the present invention, the first wheel output, which is the rotational force applied by the first wheel to the first roller, and the second wheel output, which is the rotational force applied by the second wheel to the second roller, are obtained by calculation. . Then, for example, if the second wheel output is a value larger than the first wheel output, the torque command value for the second roller torque adjusting means is more than the torque command value for the first roller torque adjusting means by 1, It is set to increase by the difference of the second wheel output. That is, the total torque command value for applying a load according to the traveling state to the test vehicle is distributed according to the values of the first wheel output and the second wheel output, and based on the distributed torque command value. Thus, the first roller torque adjusting means and the second roller torque adjusting means are driven. Therefore, a traveling load corresponding to the values of the first and second wheel outputs is applied to the first and second wheels. Therefore, even when the rotation speeds of the first roller and the second roller are frequently changed, the two rollers are accelerated and decelerated at substantially the same rotational acceleration. As a result, the speed difference between the two rollers hardly fluctuates with respect to the set speed difference, and the speed difference control is favorably performed.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is an overall block diagram of the chassis dynamometer speed difference control device according to the present embodiment, and FIG. 3 is a side view showing the direction of the rotational force applied to the rollers of the chassis dynamometer according to the present embodiment. The chassis dynamometer 1
Front wheel rollers 10a, 10b (hereinafter, front wheel rollers 10) that contact and support front wheels 4a, 4b (hereinafter, front wheels 4) of test four-wheel drive vehicle 2 from below, and four-wheel drive vehicle 2 for test. Rear wheels 6a, 6b (hereinafter, rear wheels 6), rear wheel rollers 50a,
50b (hereinafter, rear wheel roller 50). That is,
The front wheel 4 and the front wheel roller 10 are the first wheels described in the claims.
The rear wheel 6 and the rear wheel roller 50 correspond to the second wheel and the second roller. This front wheel roller 10
Are made of equal diameter and are coaxially connected by a drive shaft 16. One end of the drive shaft 16 is a front wheel rotating machine 14 for applying a predetermined torque to the front wheel roller 10.
Are connected. The rear wheel roller 50 is also manufactured with the same diameter as the front wheel roller 10, and is coaxially connected by a drive shaft 56. The rear wheel rotating machine 54 is also connected to one end of the drive shaft 56.

While the test four-wheel drive vehicle 2 is accelerating, FIG.
As shown in (1), the front wheel 4 and the rear wheel 6 apply a rotational force to the front wheel roller 10 and the rear wheel roller 50. Here, the rotational force applied by the front wheel 4 to the front wheel roller 10,
That is, the force corresponding to the force by which the front wheels 4 kick the ground is the front wheel tire output Sf. The rotational force applied by the rear wheel 6 to the rear wheel roller 50 is the rear wheel tire output Sr. At this time, the front wheel rotating machine 14 resists the front wheel tire output Sf with respect to the front wheel roller 10 so that the front wheel 4 of the test four-wheel drive vehicle 2 receives a load from the front wheel roller 10 that is substantially equal to that during actual running. The torque Tf is applied. That is, the front wheel rotating machine 14 functions as a generator for giving a predetermined rotational resistance to the front wheel roller 10. Similarly, the rear wheel rotating machine 54 resists the rear wheel tire output Sr with respect to the rear wheel roller 50 so that the rear wheel 6 of the test four-wheel drive vehicle 2 receives a load substantially equal to that during actual running. The torque Tr is added.

While the test four-wheel drive vehicle 2 is decelerating, the front wheel rotating machine 14 and the rear wheel rotating machine 54
The rotational force applied to the rear wheel roller 50 is opposite to that during acceleration shown in FIG. That is, at this time, both rotating machines 1
The motors 4 and 54 positively rotate the front wheel roller 10 and the rear wheel roller 50 with a predetermined torque. Thereby, the front wheel 4 and the rear wheel 6 of the test four-wheel drive vehicle 2
, A load substantially equal to that during actual running is applied. As described above, the front wheel rotating machine 14 functions as a means for adjusting the torque applied to the front wheel rollers 10, and the rear wheel rotating machine functions as a means for adjusting the torque applied to the rear wheel rollers 50 by the 54. Function.

As shown in FIG. 2, a shaft torque meter 18 for the front wheel roller for detecting the rotation torque of the front wheel roller 10 is provided in the middle of the drive shaft 16 connecting the rotating machine 14 for the front wheel and the front wheel roller 10. Installed. At the end of the drive shaft 16, a front wheel roller encoder 20 for detecting the rotation angle of the front wheel roller 10 is provided. Similarly, a drive shaft 56 of the rear wheel roller 50 is also provided with a rear wheel roller shaft torque meter 58 and a rear wheel roller encoder 60.

Next, with reference to FIG. 2, a description will be given of the speed difference control device according to the present embodiment. Front wheel roller encoder 2
The signal of 0 is input to the front wheel speed Vf detecting means 22.
The front wheel speed Vf detecting means 22 calculates the rotation angle of the front wheel roller 10 per unit time to determine the rotation speed of the front wheel roller 10. Here, since almost no slippage occurs between the front wheel 4 and the front wheel roller 10 of the test four-wheel drive vehicle 2, the front wheel speed Vf of the test four-wheel drive vehicle is calculated from the rotation speed of the front wheel roller 10. You. The value of the front wheel speed Vf is further input to the differentiating means 24, where it is differentiated to obtain the acceleration αf of the front wheel. Similarly, in the case of the rear wheel, the rear wheel roller encoder 60 and the rear wheel speed V
r detection means 62 and differentiation means 64 calculate the acceleration αr of the rear wheel 6
Is required. The acceleration αf of the front wheel 4 and the rotation torque of the front wheel roller detected by the front wheel roller shaft torque meter 18 are input to the front wheel tire output Sf calculating means 26,
Here, the front wheel 4 of the test four-wheel drive vehicle 2 is the front wheel roller 1
The rotational force applied to 0, that is, the front wheel tire output Sf is calculated. Similarly, the rear tire output calculating means 66 calculates the rear tire output Sr from the acceleration αr of the rear wheel 6 and the rotational torque of the rear wheel roller 50.

The acceleration αf of the front wheel 4 and the acceleration αr of the rear wheel 6 are averaged by the averaging means 80 and then input to the front and rear wheel inertia weight difference calculating means 82. In the front and rear wheel inertia weight difference calculating means 82, the front wheel roller 10, which is measured in advance,
The average acceleration (α
f + αr) / 2, the front wheel inertia weight M
A difference Md = (Mr−Mf) between f and the rear wheel inertia weight Mr is calculated.

The front wheel shaft mechanical loss storage means 28 measures the mechanical loss of the shaft of the front wheel roller 10 corresponding to the front wheel speed Vf (indirectly, the rotation speed of the front wheel roller 10), that is, the rotational resistance of bearings and gears. The value is stored in advance. Then, the mechanical loss of the shaft of the front wheel roller 10 according to the front wheel speed Vf is output. Similarly, the rear wheel axle mechanical loss storage means 6
8 also stores in advance the mechanical loss of the shaft of the rear wheel roller 50, and outputs the mechanical loss of the shaft of the rear wheel roller 50 according to the rear wheel speed Vr.

The total torque instructing means 90 instructs a total torque Tt to be applied to the front wheel roller 10 and the rear wheel roller 50 in order to apply a load to the test four-wheel drive vehicle 2 substantially equal to the actual running. The total torque command value Tt is distributed to the front wheel rotating machine 14 and the rear wheel rotating machine 54 in a manner described later.

Next, means for distributing the total torque command value Tt to the front wheel rotating machine 14 and the rear wheel rotating machine 54 will be described. First, the difference between the front wheel inertia weight Mf and the rear wheel inertia weight Mr calculated from the total torque command value Tt by the front and rear wheel inertia weight difference calculation means 82, that is, the front and rear wheel inertia weight difference Md =
(Mr−Mf) is subtracted. Next, the front wheel axle mechanical loss Rf output from the front wheel axle mechanical loss storage means 28 and the rear wheel axle mechanical loss Rr output from the rear wheel axle mechanical loss storage means 68
And the difference Rd between the front and rear wheels is subtracted from the total torque command value Tt. Further, a front and rear wheel tire output difference Sd = (Sr−Sf) is obtained from the front wheel tire output value Sf output from the front wheel tire output calculation means 26 and the rear wheel tire output value Sr output from the rear wheel tire output calculation means 66. After the calculation, the front and rear wheel tire output difference Sd is subtracted from the total torque command value Tt. And
The torque command value obtained by performing the subtraction on the total torque command value Tt, that is, the torque command value (Tt−Rd−Md−S)
The value obtained by multiplying d) by す る is set as the torque command value Tf of the front wheel rotating machine 14. Also, the total torque command value Tt
The value obtained by subtracting the torque command value Tf of the front wheel rotating machine 14 from is set as the torque command value Tr of the rear wheel rotating machine 54.

Here, for example, consider a case where the rear wheel inertia weight Mr, the rear wheel axle mechanical loss Rr, and the rear wheel tire output Sr are respectively larger than the front wheel inertia weight Mf, the front wheel axle mechanical loss Rf, and the front wheel tire output Sf. Under this condition, the values of the front and rear wheel inertia weight difference Md, the front and rear wheel mechanical loss difference Rd, and the front and rear wheel tire output difference Sd are positive, and the rear wheel rotating machine 5
4 is larger than the torque command value Tf of the front wheel rotating machine 14 by (Rd + Md + Sd). That is, the total torque command value Tt is distributed so that the torque command value Tr of the rear wheel rotating machine 54 is larger than the torque command value Tf of the front wheel rotating machine 14 by (Rd + Md + Sd). Accordingly, the rotational force F = (Sf + Mf + Rf-Tf) acting in the rotational direction of the front wheel roller 10 and the rotational force R = (Sr + Mr) acting in the rotational direction of the rear wheel roller 50 in FIG.
+ Rr-Tr). As a result, even when the rotational speeds of the front wheel roller 10 and the rear wheel roller 50 are frequently increased and decreased, the front wheel roller 10 and the rear wheel roller 50 are increased and decreased at substantially the same rotational acceleration. Therefore, the speed difference provided between the front wheel roller 10 and the rear wheel roller 50 hardly fluctuates.

The speed difference setting device 100 shown in FIG. 2 is a device for setting a speed difference between the front wheel speed Vf and the rear wheel speed Vr to a predetermined value, and a speed difference setting signal Vds between the front and rear wheels.
Is output. If the actual speed difference Vd = (Vf−Vr) has a deviation e with respect to the speed difference setting signal Vds, the deviation e = (Vds−Vd) is input to the torque correction calculator 102. . The torque correction calculation means 102 calculates a correction torque Th based on the deviation e, and adds the calculated correction torque Th to a torque command Tf for the front wheel rotating machine 14. As a result, the front wheel rotating machine 14
Is increased by the correction torque Th, and the torque command Tr for the rear wheel rotating machine 54 is reduced by an amount corresponding to the increase in the torque command Tf. As a result, the front wheel speed Vf and the rear wheel speed Vr change, and the value of the speed difference Vd is corrected. That is, feedback control is performed so as to eliminate the deviation e.

According to the speed difference control device according to the present embodiment,
For each of the front wheel roller 10 and the rear wheel roller 50, ideal torque values Tf and Tr for maintaining a predetermined speed difference are obtained, and these are the front wheel rotating machine 14 and the rear wheel rotating machine 54.
Distributed to Therefore, the front wheel roller 10 and the rear wheel roller 50 are accelerated and decelerated at substantially the same rotational acceleration, and the speed difference Vd between the front wheel roller 10 and the rear wheel roller 50 hardly fluctuates. However, even in the above method, if the speed difference Vd still deviates from the speed difference setting signal Vds, the speed difference Vd is controlled by feedback control so as to match the speed difference setting signal Vds. Therefore, even when the speed of the test four-wheel drive vehicle 2 is frequently changed, the speed difference control between the front wheel 4 and the rear wheel 6 is favorably performed.

In the case of the present embodiment, the test four-wheel drive vehicle 2
Although the example in which the speed difference control is performed between the front wheel 4 and the rear wheel 6 has been described, the invention is not limited to this. For example, as shown in FIGS. 4 and 5, it is also possible to perform speed difference control between the left and right wheels, and it is also possible to arbitrarily change the combination in which speed difference control is performed.

According to the present invention, good speed difference control can be performed even when the rotation speeds of the first and second rollers fluctuate frequently. For this reason, the speed difference control in the acceleration state or the deceleration state of the vehicle can be freely performed.

[Brief description of the drawings]

FIG. 1 is a block diagram schematically showing an outline of the present invention.

FIG. 2 is an overall block diagram of a speed control device of the chassis dynamometer according to one embodiment of the present invention.

FIG. 3 is a side view showing a direction of a rotational force applied to a roller of the chassis dynamometer according to one embodiment of the present invention.

FIG. 4 is a plan view (1) illustrating a state in which speed difference control is performed between right and left wheels.

FIG. 5 is a plan view (2) illustrating a state in which speed difference control is performed between right and left wheels.

[Explanation of symbols]

Reference Signs List 10 front wheel roller (first roller) 14 front wheel rotating machine (first roller torque adjusting means) 18 front wheel roller shaft torque meter (first roller rotation torque detecting means) 20 front wheel roller encoder (first roller rotation acceleration calculation) Means) 22 front wheel speed Vf detecting means (first roller rotational acceleration calculating means) 24 differentiating means (first roller rotational acceleration calculating means) 26 front wheel tire output calculating means (first wheel output calculating means) 50 rear wheel roller (second wheel) Roller) 54 Rotating machine for rear wheel (torque adjusting means for second roller) 58 Shaft torque meter for rear wheel roller (second roller rotating torque detecting means) 60 Encoder for rear wheel roller (second roller rotating acceleration calculating means) 62 Rear wheel speed Vr detecting means (second roller rotational acceleration calculating means) 64 Differentiating means (second roller rotational acceleration calculating means) 66 Rear wheel torque Ya output calculation means (first wheel output calculating means) 90 total torque command means

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Claims (1)

(57) [Claims] 1. A first roller and a second roller rotating in contact with a first wheel and a second wheel of a test vehicle, respectively, and the first and second rollers are given to the rollers. In a chassis dynamometer including a first roller torque adjusting unit and a second roller torque adjusting unit for applying a rotational force to each roller or a force for braking the rotation thereof against the rotational force, A speed difference control device for performing a pseudo running test in a state where the rotation speed difference between the second rollers is kept constant, wherein the rotation speed of each of the first and second rollers is detected and this rotation speed is detected. A first roller rotational acceleration calculating means for calculating the rotational acceleration of the first and second rollers by differentiating;
Roller rotation acceleration calculation means; first roller rotation torque detection means for detecting rotation torque of each of the first and second rollers; second roller rotation torque detection means; rotation torque value of the first roller; The first wheel of the test vehicle is moved to the first wheel based on the rotation acceleration value of one roller.
A first wheel output calculating means for calculating a rotational force applied to the roller; and a second wheel of the test vehicle being driven by a second wheel based on a rotational torque value of the second roller and a rotational acceleration value of the second roller.
Second wheel output calculating means for calculating a rotational force applied to the roller; wheel output difference calculating means for calculating a difference between the first wheel output calculated value and the second wheel output calculated value; A total torque command unit that commands a total torque applied to the first roller and the second roller to apply a load according to a state; and a wheel output difference from a total torque command value obtained by the total torque command unit. A wheel output difference correcting means for subtracting, a first torque command value after the wheel output difference correction is performed, and the equally divided torque command value output to the first roller torque adjusting means; Roller torque command means, and subtracting the output value of the first roller torque command means from the total torque command value and outputting the subtracted torque command value to the second roller torque adjusting means. 2 Speed difference control device for a chassis dynamometer, characterized in that it comprises a chromatography La torque command means.