DE1513252A1 - Electrical device for the operation of reels for metal strips - Google Patents

Description

LIGSNTIA PATENT-VERWAITUIiGS-G-M.B.H. 6 Prankfurt / Main, Theodor-Stern-Kai 1

Wegener / nl P 15 13 25 2.2

23. 1. 69 (L 4-9 906)

Electrical device for operating winding reels for metal strips.

Winding devices for metal strips usually have to be in the Be able to have a re ' to enable relatively high tape tension, while when winding ' Band of small band thickness only a relatively low band tension is required. Have such winding devices a winding mandrel, which in most cases is operated directly or via an intermediate gear unit from one or more direct current shunt motors is driven.

Up to now, the collar diameter that changes during winding has been adjusted with normal collar diameter ratios the shunt excitation of the relevant DC motor is taken into account. Accordingly, the engine has become with a PeId weak area provided that corresponded to the collar diameter range. During the winding process, at essentially With the armature current kept constant, the shunt excitation is increased proportionally to the increasing collar diameter. Included is the adjustment range that corresponds to the ratio of maximum to

909828/0844 _ba d

(L 49 906)

corresponds to the minimum collar diameter, limited by the permissible field weakening. A winding drive has therefore been provided for larger coil diameter ratios the motor field up to a certain collar diameter was continuously amplified with a constant armature current. When the engine had reached its full field, it was then the armature current increases continuously while the motor field is kept constant at its maximum value became. Both winding drives were wound according to the principle of constant power, with the winding process in each case began at full field weakening. D-like winding urine drives have the disadvantage that the start-up of the winding reel to speeds below its maximum speed because of the field weakening that occurs in any case, relative going slowly. In addition, normal DC shunt motors are less at full field weakening shock-overloadable than with full shunt excitation. Has a motor that is sufficiently dimensioned for these conditions but a relatively large moment of inertia that changes when the belt speed changes the accuracy of compliance with a desired tape tension and the required Peak current in the armature circuit of the motor continues to increase.

Up to now the assumption has been made, that is, with constant Belt speed the motor power required for the reel is constant regardless of the coil diameter may be. This also applies to one from the German interpretation B 35 70S VIIIb / 21c of October 18, 1956 which became known Winding device too. In order to achieve a constant belt tension even when the belt speed changes, the known device provides for the torque of the reel motor required for a constant strip tension on an ongoing basis

BAD ORiGINAL

909828/0844

(L 49.906)

taking into account the influencing variables friction and Acceleration or deceleration with the help of an analog computing device to build. The torque of the reel motor calculated in this way is then primarily over. its field circle regulated. The start of winding takes place here too when the field weakening of the motor. Such However, the winding device only gives a constant one Tape tension when used for winding relatively thin tapes becomes, as has been the case up to now, for example in cold strip mills.

Man; however, it is more and more going on, especially on Hot strip mills to roll strips of greater thickness, for example up to 18 mm. This results in points of view which must be strictly observed when executing the reel control. In all previous reel regulations, the torque required to bend the strip during winding was not included in the determination of the motor size still taken into account when selecting the drive control ..

This bending moment decreases with increasing collar diameter easily off. As a first approximation, it can be compared to the collar diameter can be accepted independently and can easily * are in the order of magnitude of the belt tension. Neglection this moment would mean that with constant engine power the belt tension is no longer constant, but rather increases continuously according to the growing collar diameter. If the bending moment is taken into account, the one for a certain bundle speed and a constant one B. "aiG2ug required engine power no longer constant, but decreases with increasing collar diameter.

.3ie-r: enu> nent depends on the bandwidth, on the square of the

909828 / 08U bathroom

Tape thickness and the yield point of the material to be wound at Vickel temperature and belt speed. For example, for a special steel of ^ 2.7 mm thickness the required bending moment approx. 700 kpm. The required The belt pulling torque is between 220 and 590 kpm, depending on the variable collar diameter. At the start of wrapping so the bending moment is about three times as large as the belt tensile moment. ■

For reasons of rolling technology, thick material is made with smaller, Speed, thin material rolled at high speed. It follows that the reel motor power when rolling "of thick material, ie in the lower winding speed range mainly due to the bending and the belt tension and when rolling thin material, i.e. in the upper winding speed range, is mainly determined by the belt tension alone * - -

Based on these findings, the invention, which is of particular importance for the coil tension control on the take-up reel of a continuous broadband hot rolling mill, is based on the task, the mode of operation of winding reels for metal tape to improve and the size of the associated To keep winding mandrels driving motors as small as possible * -. · .-.

The invention is based on a prior art given by the above-mentioned reference and relates to an electrical device for operating winding reels for metal strip using an individually fed coupled to the reel, with a comparison of an armature current target value -the armature current actual value via the armature- ^ circuit regulated direct current life-circuit motor, whose secondary _{circuit excitation by (} a circuit arrangement automatically

909828/0844

-5 - P 15 15 25 2.2

(L 49 906) *

is adjustable, as well as a continuously working computing device, which determines the outer diameter of the lap bundle, from this and the tape tension target value and additionally a belt speed changes and the flywheels 'for the purpose of acceleration compensation taking into account the required engine torque calculated, which also the actual existing value of the lift-closing excitation is determined and by dividing the calculated engine torque by this value calculates the required armature current setpoint and adjusts.

The known device is avoided while avoiding the described Disadvantages according to the invention improved in that to take into account a curvature of the tape during winding of coils required bending moment an additional on the computing device acting, adjustable and one preferably independent of the collar diameter provided portion of the torque size determining adjusting device. is arranged and that a circuit arrangement for the armature voltage-dependent for the adjustment of the lift-closing excitation Field weakening is provided and designed such that the Field weakening only starts when almost the permissible, upper limit value of the armature voltage of the motor has been reached.

Although circuit arrangements for armature voltage-dependent field weakening were sufficiently known, see, for example, AEG Mitteilungen 1958 ₅ pages 630/31 and 646 / 47j, the advantageous application possibility for regulating winding reels had not yet been recognized. Rather, as soon as a field weakening range of the motor was provided to take account of the variable collar diameter, use was made of the field weakening in every case. On the other hand, if you wanted to consider the bending moment as a further influencing variable in the known winding device.

'.' - 909.828 / 0844

- 6 - P 15 ^ 3 252.2

(L 4-9 906)

then this would only be in the same way as already with the influencing variables acceleration torque and friction torque possible. Apart from the fact that this would initially require the influence and course of the bending moment were recognized at all during the winding process, this would, however, be the previous one, including the known arrangement the underlying principle of the EMF regulation is retained and 'inevitably require systems (motor and converter) that are many times larger.

Only the simultaneous use of the inventively provided ' Suggested measures to take into account the bending moment in connection with the measures for the armature stress-dependent Field weakening allow an improvement in the operation of reels for metal strip and a reduction in size the size of the reel motor. Thick material is at constant maximum shunt excitation of the motor and accordingly the · required motor speed increased armature voltage and thus also higher power wound. The regulation takes place here in the anchor circle. With thin material, depending on Belt speed in the upper armature voltage range with corresponding Field weakening worked. In the latter case, the regulation takes place both in the armature and in the "field circuit" of the motor. In addition to the above, such a solution offers the following advantages:

1. The fact that at low belt speeds, i.e. with thick material, with full shunt excitation the motor is being worked on, in these cases stands for acceleration, deceleration or other control processes the full engine torque is available.

2. Since up to a certain belt speed with full shunt excitation and corresponding current control work is being carried out, but thick material during the winding process with increasing waistband diameter.

909828/0844

(L 49 906)

knife requires a decreasing engine power and speed, a smaller engine can do the job Winding program can be implemented as with a shunt excitation of the motor also influencing in this case Regulation.

It should also be noted that "in the case of the known Belt tension control device, a proportion of the required motor torque is taken into account, which is independent of the outer diameter of the wrap is. However, this proportion is not operationally adjustable and should be relatively small Correction variable take the bearing friction torque into account. This frictional torque lies in the reels in question here at least one order of magnitude below the maximum belt tensile torque.

The invention is further explained using a Basic circuit diagram of a strip tension control shown in the figure of a winding reel of a continuous broadband hot rolling mill.

In the figure, a metal strip 1 moves in the direction of the arrow onto a winding reel which contains a winding mandrel 3. A winding collar 2 is formed on the latter. The band tension in the metal band 1 is applied by a direct current shunt motor; whose armature m ± t 5 i? Jid whose shunt field is denoted by 6. The counter-tension is applied by a driving apparatus 4 or a roll stand, not shown in detail. The feeding of the, Hotoranker _: 5 takes place via a converter 7 from one. Three-phase network .8 «. The valves of the converter 7, not shown in detail, are controlled with the aid of: Phase 1. ^: -ge displaceable control pulses which are emitted by a control device 9. The phase position

»The, control pulses are generated with the aid of a control amplifier 10 determined;. on its .input the in connection point 12

909828/0844 bad original

(L 49 906)

Difference obtained between the armature current setpoint and the armature current actual value acts. The armature current actual value is obtained with the help of a current transformer 11 is detected. .

An armature current setpoint value is initially applied for a start-up of the motor 5, 6 in that a voltage is applied to the input 60 of an integration element 17. This takes place after a switch 18 has been closed and switch 62 has been opened. The output voltage of the integration element 17 rises linearly in time and is compared at node 20 with the armature voltage of a tachometer machine 19, which is coupled to the motor 5, 6. The speed control deviation thus formed is used, after amplification in an amplifier 16, as an armature current setpoint value, which acts on node 12. As soon as it has been established, for example photoelectrically, that the tip of a strip 1 running to the Vickel reel has been detected by the winding mandrel 3, a. Switch 21 closed, as a result of which amplifier 16 receives a significantly higher input voltage via node 20. In a device 13, the output variable of the amplifier 16 serving as the armature current setpoint value is limited to a value which has been determined in a computing device. This computing device has an output I5, which feeds the device 13 via a monitoring device 14 and initially defines its limit values, the armature current setpoint value. The monitoring device 14 prevents the limit values from being able to assume impermissible sizes. The monitoring device 14 ensures that the maximum values of the armature current setpoint value are adapted to the still permissible peak current of the motor armature 5. For this purpose, the motor speed can act on an input 63 ′ on the monitoring device 14 and the shunt excitation of the motor 5, 6 acts on an input 64.

909828/0844

(L 49 906) ■

The excitation current of the motor 5 »6, ie. the current in the field winding 6 is controlled via an amplifier 27 ″ with a comparison between the field current setpoint value and the field current actual value taking place in the node 22. The field current m actual value is recorded with the aid of a current transformer 26. The field current setpoint value is determined via a Input 23 of a sufficiently known circuit arrangement 25, not shown in detail, for armature voltage-dependent field weakening. The arrangement 25 has a further input 24 on which the armature voltage of the motor 5 - 6 acts Exceeding the bias voltage leads to a current that reduces the field current setpoint value. The bias voltage can be around 95 % of the maximum value of the armature voltage. As soon as the armature voltage exceeds the bias voltage, the field current setpoint value and thus the excitation current in the winding 6 increasing is reduced / this will only be the case at a significant speed of the engine5.

Tachometer machines 40 and 41 are used to determine the outside diameter of the Vickel collar 2. The tachometer machine 40 is coupled to the driving apparatus 4 and supplies a voltage proportional to the belt speed. The tachometer machine 41 is with the motor 5 ?. 6 and the winding mandrel 3 coupled. The voltages of the two tachometer machines 40 and 41 are compared at node 42. The differential voltage formed in this way controls an amplifier 43, which feeds the closed circuit 44 of the Tuchonietermi-achine 41. With the appropriate design: the tachometer bidder machine 41 "'is proportional to the exciter flow rate. Servant exciter flow l: jt then: ·.!

BAD QBiGINAL 909828/0844

- 10 -. P 15 15 25 2.2

(L 49 906)

speed and speed of the Vickel mandrel 3 is a measure of the outer diameter D of the winder collar 2. The diameter value D determined in this way is used to calculate the required motor torque used.

A potentiometer 46 is opened by means of an IT run-on control set the diameter value. This setting value is set at node 45 with one of the field current of winding 44 proportional size compared. The difference formed in this way controls a servomotor 47 via an amplifier 48 The angle of rotation oC is then the outer diameter D of the winding collar 2 proportional. With the one set by the servomotor 47 Sliders of potentiometer 46 are mechanically coupled to sliders of potentiometers 49 and 50.

The desired strip tension in the metal strip 1 is preselected with the aid of a potentiometer 51. The output of the potentiometer 51 is set with the set value proportional to the diameter D. of potentiometer 49 is multiplied. The output size of the last-mentioned potentiometer is therefore the same. desired belt tensile torque proportionally. For consideration the width of the metal strip 1 is used by potentiometers 56 and 57> whose grinders are mechanically coupled to one another. The potentiometer 57 and potentiometers 58 and 59 are used for setting of the individual factors as independent of the bundle diameter D assumed bending moment. With the potentiometer 58 the square of the tape thickness and with the potentiometer 59 the yield point of the material to be wound must be taken into account.

A computing device 52 is used to compensate for at Belt speed changes occurring flywheel effects required portion of the engine torque is calculated. on an input 53 acts a corresponding to an empty winding mandrel 3 Input variable. The acts on an input 54

909828/0844 bad original

(L 4-9 906)

a potentiometer 50 adjusted diameter value. A Input 55 takes into account the bandwidth set on potentiometer 56. In the present case, the outcome comes the computing device 52 via a switch J6 at a further acceleration after the start of Winder or when the Vickel reel is decelerated to take effect.

From the three torque components of band tension torque, bending torque, acceleration and deceleration torque, three components 28, 29 and 50 which determine the armature current target value are calculated by forming a quotient with the excitation flow $ of the motor 5, which act on the output 15 of the entire arithmetic unit. The excitation flux $ is determined from the actual field current value detected with the aid of a current transformer 26 via a simulation 57 of the magnetization characteristic of the motor 5v 6. The output value of the simulation 37 is compared in the node 38 with the setting value of an overrun potentiometer 34-. The differential voltage formed in this way controls, via an amplifier 39, a servomotor 31Y, the angle of rotation of which is proportional to the excitation flux φ . With the wiper of the potentiometer 54- wipers of potentiometers 32, 33 and 35 are coupled. The tap voltages of the potentiometers 32, 33 and 35 are selected so that the minimum tap voltages correspond to the maximum excitation flow § , which is simulated on the NacBil on potentiometer 3 ^. Conversely, the minimum excitation flux corresponding maximum tap voltages at the potentiometers 32, 33 and 35 · It is readily possible, in place of the potentiometer 32, 33 and 35 a common actuator to provide the output of the first size φ is proportional Erregerlluß. The formation of the quotient could then take place with the aid of an additional electronic amplifier, as in the case of the known tension control device. Instead of the potentiometers shown here, inductive, capacitive or electronic actuators can also be used.

909828/0844 bad original

(L 49 906)

The switch 18 is opened to brake the winding reel. At the same time, switches 62 and 56 are closed. The switch 56 is used to do what is necessary to clear the road Influencing the armature current setpoint. This influence can lead to a reversal of the sign of the armature current setpoint and armature current of the motor 5j 6 result. A voltage 61 causes the integration device via the contact 62 and: I7 in. Not to be explained in more detail here Way the final shutdown of the winding reel.

Patent claims :

909828/084

Claims (1)

LIGENTIA PATENT-VERVAIiTIJNGS-G.M.B.H, 6 Ir ankfur t / Main, Theodor-Stern-Kai 1 Wegener / nl ■ _'- .. P 15 15 252.2 23.1. 69 (L-49 906) P ate nt ans ρ r ü g h e 1. Electrical device for operating winding reels for metal tape using a with the. Reel coupled individually fed, comparing one Armature current setpoint with the armature current actual value above the armature circuit regulated direct current shunt motor, whose shunt excitation is automatically adjustable by a circuit arrangement, and one continuously working computing device, which determines the outer diameter of the lap bundle, from this and the tape tension setpoint and additionally a belt speed change and the flywheel masses for the purpose of acceleration ■ Compensation taking into account the required motor torque is calculated, which also determines the actually existing value of the shunt excitation and through Division of the calculated motor torque by this value calculates the required armature current setpoint and sets, characterized in that to take into account a curvature of the tape (T) when winding 909 82 8/08 n / a Ίψ P 15 15 252.2 (L 49 906) of collars (2) required bending moment an additional on the computing device acting, adjustable and determining a portion of the torque magnitude that is preferably provided independently of the collar diameter (D) Adjusting device (57 ··· 59) is arranged and that for the. Adjustment of the shunt excitation one Circuit arrangement (23,24,25) for armature voltage-dependent field weakening • is provided and designed in such a way that that the field weakening only starts when almost the permissible, upper limit value of the armature voltage of the motor (5,6) has been reached. . Device according to Claim 1, characterized in that a monitoring device (14) is provided for the armature current setpoint value (13, 15), which monitors it in accordance with the permissible peak value of the armature current dec motor (5? 6) limited. 909828/08 A A