JP2767981B2 - Deceleration control method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deceleration control method suitable for controlling winding of a long object including a steel plate.

[Conventional technology]

FIG. 4 shows a conventional control device for the winding machine. In the figure, 1, 1A is an upper limiter, 2 is an automatic deceleration signal generator, and 4 is a shockless signal generator. In normal operation, the acceleration operation with a rate of acceleration α by an acceleration command from a stop state, operating at a constant speed V ₀ when it reaches the set speed V _0.

Incidentally, a deceleration command may be input during the acceleration operation at a certain acceleration rate α as described above. In such a case, conventionally, for example, when a certain set speed V ₀ is reached, the upper limiter 1 The automatic deceleration signal from the automatic deceleration signal generator 2 is determined as V _L = (2βL ₀ ) ^{1/2 based on} the length L ₀ (winding length set value−winding length actual value) and the deceleration rate β.
Generally, an automatic deceleration stop is performed by changing the upper limit value to _VL .

FIG. 5 shows the speed command signal V ^* in such a case, and FIG. 6 shows the speed command signal V in such a case.
The relationship between ^* and the acceleration / deceleration rate is shown. FIG. 6A shows the speed command signal V ^* , FIG. 6B shows the acceleration / deceleration rate (acceleration rate α, deceleration rate β) without shockless control, and FIG. 6C shows the rate with shockless control. Acceleration / deceleration rate (speed rate α, deceleration rate −β,
Acceleration / deceleration rate change rates b, -b) are shown.

[Problems to be solved by the invention]

However, when switching from acceleration to deceleration in the method as described above, a rapid change in the speed command signal V ^* occurs when shifting from acceleration to deceleration as shown in FIG. There is a problem that breakage, slippage, product failure, stop position failure, and the like occur.

Therefore, an object of the present invention is to prevent a sudden change in speed command from occurring and to improve control performance.

[Means for solving the problem]

When performing acceleration operation from a stop or constant speed operation state while performing position control, and decelerating during acceleration, the amount of movement so far during acceleration and the difference between the movement amount set value and the actual movement amount value are indicated. A speed limit value is calculated from the sum of the length, the acceleration rate, and the deceleration rate. If the speed limit value is reached during acceleration, the speed is limited to this speed, and after a certain period of operation, the vehicle is decelerated.

[Action]

If the above speed limit value is reached during acceleration, the speed is limited to this speed and the vehicle is driven for a certain period of time and then decelerated to prevent a sudden change in the speed command.

〔Example〕

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

In the figure, 1, 1A is an upper limiter, 2 is an automatic deceleration signal generator composed of a computing unit, etc., 3 is an automatic deceleration interference suppression signal generator also composed of a computing unit, etc., 4 is a shockless composed of a function generator, etc. In the signal generator, the upper limiter 1 is the speed set value
Outputs the smaller of V ₀ and the automatic deceleration signal _VL . Upper limiter 1A outputs the output of upper limiter 1 and automatic deceleration interference suppression signal generator 3
^Is output as the speed command value V ^** via the shockless signal generator 4.

That is, assuming a winder here, the accelerating operation is performed at a certain acceleration rate α by an acceleration command from a stopped state,
When the speed limit value V _TOPHL is reached, the _motor is driven at that speed for a certain period of time, then automatically decelerated at the deceleration rate β and stopped. That is, the fifth
Instead of as shown in the figure, when shifting from acceleration to deceleration, by decelerating after passing through a certain speed as shown in FIG. 2,
FIG. 3 shows the relationship between the speed command and the acceleration / deceleration rate at that time, in which a sudden change in the speed command is prevented. This figure is the same as FIG. 6, (A) is the speed command signal V ^* , (B)
Is the acceleration / deceleration rate without shockless restriction (acceleration rate α, deceleration rate β), (c) is the acceleration / deceleration rate with shockless control (acceleration rate α, deceleration rate -β, acceleration / deceleration rate change rate b, -b) Are respectively shown.

The speed limit value V _TOPHL is _obtained by the automatic deceleration interference suppression signal generator 3. The method for _{obtaining the} speed limit value V _TOPHL will be described below.

Now, when the current speed during acceleration and V _IST0, the distance L ₁ which is considered to have moved at this speed, the acceleration and alpha, is given by the following equation.

On the other hand, 'When, from the relationship of FIG. 2, L' remaining length from the previous stop position to the next stop position L = L ₀ + L ₁ ... a (2). Also, the maximum arrival speed that can be predicted from the stopped state
Assuming that V _TOP is an acceleration rate is α, and a deceleration rate is β, the following relationship is established between these and the remaining length L ′.

By transforming equation (3), V _TOP = {2αβL ′ / (α + β)} ^1/2 (4) Therefore, the speed limit value V _TOPHL is _calculated by (4)
It is expressed as follows by multiplying the equation by a limiting constant K.

As described above, the shockless control is performed by the shockless signal generator 4 with each change rate of the acceleration rate α and the deceleration rate β as b. However, the dead time at a constant speed after the completion of the acceleration shown in FIG. It is desirable to make t _c as close to 0 as possible, and the adjustment is performed using the limiting constant K described above.

Although the winding control has been mainly described above,
The present invention can be generally applied to those which perform the same position control. Further, although an example in which the acceleration is started from the stop position has been described here, the case where the acceleration is started from a constant speed can be applied in the same manner as described above.

Further, in the above description, the speed limit value is obtained by using the automatic deceleration interference suppression signal generator, but may be obtained by software.

〔The invention's effect〕

According to the present invention, when acceleration is started from a stop state or a constant speed state, an arithmetic circuit for calculating a speed limit value is added to predict this speed limit value, and after acceleration is completed, the speed is limited to this speed and fixed. After a period of operation, the vehicle is decelerated and stopped, so that a rapid change in the speed command can be eliminated, and as a result, there is obtained an advantage that breakage, slippage, product defects and stop position defects can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is an explanatory diagram for explaining an example of a speed command in FIG. 1, and FIG. 3 is a relationship between a speed command and an acceleration / deceleration rate in FIG. FIG. 4 is a block diagram showing a conventional control device for a winder, FIG. 5 is an explanatory diagram for explaining an example of a conventional speed command, and FIG. 6 is a conventional speed command. FIG. 4 is an explanatory diagram for explaining a relationship between a command and an acceleration / deceleration rate. 1, 1A: Upper limiter, 2: Automatic deceleration signal generator, 3: Automatic deceleration interference suppression signal generator, 4: Shockless signal generator.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-49-37342 (JP, A) JP-A-51-74183 (JP, A) JP-A-51-53189 (JP, A) JP-A-54-37189 79374 (JP, A) JP-A-2-197907 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G05D 3/12 306

Claims (1)

(57) [Claims] An acceleration operation is performed from a stop or a constant speed operation state while performing position control, and when deceleration is performed during acceleration, the amount of movement so far during acceleration, the movement amount set value, and the actual movement amount value are compared. The speed limit value is calculated from the sum of the remaining length indicated by the deviation, the acceleration rate, and the deceleration rate. If the control value is reached during acceleration, the speed is limited to this speed, the vehicle is driven for a certain period of time, and then deceleration is performed. Deceleration control method.