JP2671354B2 - Differential rotation control device - Google Patents

Description

The present invention relates to a test device for a power transmission system including a differential mechanism, and more particularly to a differential rotation control device for a differential mechanism.

B. SUMMARY OF THE INVENTION The present invention is directed to performing automatic speed control of a pair of rotating bodies by matching a differential rotation detection signal of a pair of rotating bodies coupled to a differential mechanism and a differential rotation setting value. A pulse signal with a frequency corresponding to the value is combined with one of the speed detection pulse signals of the pair of rotating bodies, and the combined speed detection pulse is used as the up input and the down input of the up / down counter, and the differential rotation is applied to the count value of the counter. By obtaining the set value, the transient response accuracy can be improved.

C. Conventional technology For chassis dynamometers and power train testers of automobiles, performance tests are performed including differential gears. In a power transmission system testing device including such a differential mechanism, the differential mechanism may cause a difference in the rotational speeds of the left and right wheels. Therefore, the differential rotation is controlled to be zero (simulating the straight running of an automobile). , Or the differential rotation is controlled to a constant value (simulating left turn or right turn).

For this reason, the conventional differential rotation control device is configured as shown in FIG. The dynamometer control system puts the wheels 1A and 1B of the test vehicle 1 on rollers 2A and 2B, respectively, and applies the driving force of the wheels 1A and 1B driven by the engine of the vehicle 1 to the dynamometers 3A and 3B coupled to the rollers 2A and 2B. Absorb individually. Dynamometers 3A and 3B are torque controllers 4A and 4B and speed controllers 5A and 5A.
Automatic control of torque and speed is performed by B or the like.

In contrast to such a dynamometer control system, the differential rotation control device detects the rotation speeds of the dynamometers 3A and 3B (the rotation speeds of the wheels 1A and 1B) by the pulse pickups 6A and 6B.
A and B are converted into voltage signals by frequency-voltage converters 7A and 7B, respectively, and a difference rotation is detected by subtraction of both conversion signals, and a digital setting value of the difference rotation setting unit 8 is converted by a D / A converter 9. The deviation between the set signal and the differential rotation detection signal is calculated and amplified by a proportional-integral (PI) calculator 10, and the output of the calculator 10 is added to the set value of the speed setting device 11 to adjust the speed command of the dynamometer 3B. The output of the arithmetic unit 10 is subtracted from the set value of the speed setting unit 11 to obtain a speed command value of the dynamometer 3A.

Here, in order to compensate for the steady-state deviation of the differential rotation, the difference calculation unit 12 calculates the difference (AB) between the count values of the detection pulse signals A and B of the pulse pickups 6A and 6B per unit time (AB) by the deviation calculation unit 12. Are compared with each other, and the deviation E is integrated by the integration operation unit 13, and the integration result is converted into an analog signal by the D / A converter 14 to obtain a differential rotation correction value.

D. Problems to be Solved by the Invention In the conventional differential rotation control device, the deviation calculation unit 12 and the integration calculation unit 13 can perform high-precision differential rotation control without steady deviation, but in the transient state of the differential rotation control. There was a problem that the response accuracy could not be improved.

This is because there is a delay due to the sampling time for counting and matching the pulses in the deviation calculation unit 12 and the integration time in the integration calculation unit 13, and the longer the time is, the more the steady-state deviation compensation accuracy is improved. This is due to the fact that the transient deviation becomes a dead time and is accompanied by a compensation delay, which deteriorates the transient response.

An object of the present invention is to provide a differential rotation control device that can improve the accuracy of differential rotation control including a transient state.

E. Means and Actions for Solving the Problems In order to achieve the above object, the present invention provides a pair of rotating bodies coupled to a differential mechanism, a differential rotation detection signal and a differential rotation set value of the pair of rotating bodies. In a test apparatus for a power transmission system including a speed control system that automatically controls the differential rotation speed of both rotating bodies by abutting against each other, frequency adjusting means for obtaining a pulse signal having a frequency according to the differential rotation set value and the pulse A pulse synthesizing means for synthesizing the signal into one of the speed detection pulse signals of the pair of rotating bodies according to the positive and negative polarities of the differential rotation set value, and both detection pulses synthesized by this synthesizing means are used as up input and down input. An up / down counting means and a matching means for obtaining the differential rotation setting value by matching the count value of the counting means and the phase difference zero setting value of the pair of rotating bodies are provided, and the difference rotation setting value is set. The number of pulses the detectable by synthesizing the pulse signal of the wave number to one of the rotational speed detection pulse signal of the rotary body to perform the automatic speed control so as to vary in accordance with the difference between the rotational settings.

F. Embodiment FIG. 1 is a circuit diagram of a differential rotation control device showing an embodiment of the present invention. Dead band circuit 21 is a pulse pickup
The detected pulse signals A and B of 6A and 6B are respectively subjected to waveform shaping and phase adjustment. This processing prevents simultaneous up and down inputs of the up / down counter in the subsequent stage. For example, when the pulse signals A and B are in the synchronous state shown in FIG. 2 (A),
The dead band circuit 21 converts the signal A into a pulse signal A ₀ having a narrow rising timing, converts the signal B into a pulse signal B ₀ having a narrow falling timing, and prohibits simultaneous generation of both signals A ₀ and B _0. .

The clock generator 22 generates a clock pulse having a predetermined frequency, and the frequency adjusting circuit 23 increases or decreases the clock pulse frequency according to the set value of the differential rotation setting device 8. Positive / negative switching circuit 24
Outputs the output pulse of the adjusting circuit 23 as one of the pulse signals C _A or C _B in accordance with the positive / negative polarity signal set in the differential rotation setting device 8 by switching from one side. The pulse synthesizing circuits 25A and 25B add one of the pulse signals C _A and C _B from the switching circuit 24 to the output pulse signals A ₀ and B ₀ of the dead band circuit 21 to obtain pulse signals A ₁ and B ₁ . The composition by this composition circuit 25A, 25B is
For example, when the pulse signal C _B is applied, one pulse is added between the pulses P ₁ and P _{2 in} FIG. 2 (B).

Of the pulse signals A ₁ and B ₁ from the pulse synthesizing circuits 25A and 25B, the up-down counter 26 uses the signal A ₁ as the up-side counting input, the signal B ₁ as the down-side counting input, and outputs the signals A ₁ and B ₁ . The difference in the number of pulses is obtained as the count value. The digital matching circuit 27 obtains the deviation as a differential rotation set value by matching the count value output of the up / down counter 26 and the set value of the phase difference setter 28. D / A converter 29 is a matching circuit 27
Is converted into an analog signal and used as a comparison signal with the differential rotation detection signal.

In such a configuration, when the dynamometers 3A and 3B are in the same speed (zero phase difference) state, the pulse pickup 6
The output pulse signals A and B of A and 6B have the same waveform as shown in FIG. 2A, and the output pulse of the dead band circuit 21 is the second pulse.
As shown in FIG. 6B, the waveforms have the same frequency but a phase difference. Then, match the clock pulse frequency or divided frequency that is the set value zero rotational difference setter 8, the output pulse signal C _A of the positive and negative switching circuit 24, C _B is not output to both. As a result, the output pulse signals A ₁ and B ₁ of the pulse synthesis circuits 25A and 25B have the same frequency, and the up / down counter 2
At 6, the current value is maintained at zero by repeating the up and down of one pulse and the deviation from the phase zero set value in the digital matching circuit 27 is obtained as zero. This deviation zero becomes the command value of the difference rotation signal, and the automatic speed control is performed so that the difference rotation detection signal also becomes zero.

Such a synchronized state is a state in which the vehicle travels straight. In this state, in order to provide the differential rotation, the differential rotation setting unit 8 is provided with the amount N and the positive or negative polarity corresponding to the right or left turn. Depending on the setting, a pulse having a frequency obtained by increasing or decreasing the ratio N to the clock of the frequency adjusting circuit 23 is generated, and this pulse is given to one of the pulse synthesizing circuits 25A and 25B by the positive / negative switching circuit 24, and the signal A ₀ or A pulse signal with an increased number of pulses (per unit time) of one of the B ₀ signals
Get A ₁ and B ₁ .

The count value of the up / down counter 26 is, for example, the input signal A ₁ on the up side by the signals A ₁ and B ₁ with the increased number of pulses.
The number of pulses of is larger than that of the signal B _{1, and the} count value starts to increase. At this time, the differential rotation command also increases due to the increase in the count value of the counter 26, and the deceleration side control of the dynamometer 3A is started. By this control, the output pulse frequency of the pulse pickup 6A is reduced, and when the pulse synthesizing circuit 25A decelerates by the increment N, the count-up of the up-down counter 26 is stopped and maintained at the count value at that time. That is, the current count value of the counter 26 is maintained at the differential rotation set value, and the rotational speed difference between the dynamometers 3A, 3B is also maintained at this differential rotation set value, and the synchronous state is established.

Therefore, fluctuations in the rotation speed of the dynamometers 3A and 3B immediately appear as an increase or decrease in the count value of the up / down counter 26,
Compared with the conventional method of detecting the fluctuation, the number of pulses per unit time and the compensation by integration are extremely small in time delay, and the accuracy in a transient state can be improved.

G. Effects of the Invention As described above, according to the present invention, a pulse signal having a frequency corresponding to the differential rotation set value is added to one of the rotation speed detection pulse signals of the pair of rotating bodies, and the combined pulse signal is input as an input. Since the differential rotation set value is obtained from the count value of the up-down counter that is used as the down input, the effect that the transient response can be increased to the rotation speed detection pulse cycle while the steady-state deviation is increased to the rotation speed detection accuracy. is there.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, and FIG.
FIG. 2 (B) is a waveform diagram of each part in FIG. 1, and FIG. 3 is a conventional device configuration diagram. 3A, 3B ... Dynamometer, 6A, 6B ... Pulse pickup, 7A, 7B ... Frequency-voltage converter, 8 ... Differential rotation setting device, 21 ... Dead band circuit, 22 ... Clock generator,
23 …… Frequency control circuit, 24 …… Positive / negative switching circuit, 25A, 25B
...... Pulse synthesizing circuit, 26 …… Up / down counter, 27
...... Digital matching circuit, 28 …… Phase difference setting device.

Claims (1)

(57) [Claims] 1. A speed for automatically speed-controlling a differential rotation speed of a pair of rotary bodies and a differential rotation speed of the pair of rotary bodies by matching a differential rotation detection signal and a differential rotation set value of the pair of rotary bodies. In a power transmission system test apparatus including a control system, a frequency adjusting means for obtaining a pulse signal having a frequency corresponding to a differential rotation set value, and the pulse signal for rotating the pair of rotations according to positive and negative polarities of the differential rotation set value. Pulse synthesizing means for synthesizing one of the speed detection pulse signals of the body, up-down counting means for inputting both detection pulses synthesized by the synthesizing means to up input and down input, the count value of this counting means and the pair of A differential rotation control device comprising: a matching means for obtaining the differential rotation set value by matching with a zero phase difference set value of the rotating body.