KR20120111523A - Tention control device - Google Patents

Abstract

PURPOSE: A tension control device is provided to maintain stable system by simultaneously stopping a velocity control motor and a torque control motor. CONSTITUTION: A tension control device comprises a velocity control motor(10) and a torque control motor(20). The velocity control motor operates in a velocity mode. The torque control motor operates in a torque mode. When an emergent stop signal is inputted during the operation of the torque mode, the torque control motor is operated in a converted state from the torque mode to the velocity mode.

Description

Tension Control Device {TENTION CONTROL DEVICE}

The present invention relates to a tension control device, and more particularly, to a tension control device capable of stopping the torque control motor and the speed control motor at the same time in order to maintain a stable tension even when the system suddenly stopped.

Tension control devices using inverters drive rollers simultaneously in a series of production lines in the steel, paper, textile and film industries. The purpose of the control of the roller for the continuous process is to maintain a constant line speed of the line while maintaining a constant tension on the material.

The tension control device has two modes, a speed control mode and a torque control mode, and the control mode that is applied varies depending on the type and characteristic of the material. Both modes use the Quick Stop function to suddenly stop the interlocking system when an accident occurs during interlocking motion.

However, if an emergency stop is input while the system is operating in the torque control mode and the system is suddenly stopped, there is a risk that the system may be damaged due to a different time for stopping the speed control motor and the torque control motor.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a tension control device capable of stably stopping a speed control motor and a torque control motor even when an emergency stop is input and the system is suddenly stopped. .

It is also an object of the present invention to provide a tension control device that can be stopped at the same time all the motors that interlock at the time of sudden stop of the system.

According to an aspect of the present invention, there is provided a tension control device, including: a speed control drive motor operating in a speed mode and a torque mode; And a torque control drive motor operating in the torque mode. When an emergency stop signal is input during operation in the torque mode, the torque control drive motor may operate by converting from the torque mode to the speed mode.

In addition, the speed mode may be a mode in which the linear speed of the speed control drive motor or the torque control drive motor is controlled and operated during motor rotation.

The torque mode may be a mode in which the torque of the speed control drive motor or the torque control drive motor is controlled and operated in the rotation of the motor.

The apparatus may further include an emergency stop device for receiving the emergency stop signal from a user.

The speed control drive motor and the torque control drive motor may be motors for rotating a cylinder.

According to the tension control device according to one aspect of the present invention, even when an emergency stop is input and the system suddenly stops, it is possible to stop the speed control motor and the torque control motor at the same time, thereby creating an environment in which the system can be stably maintained. Can provide.

1 is a view showing a basic environment in which the tension control device according to an embodiment of the present invention is used,
2 is an algorithm illustrating an operation of a torque control drive motor operating in a torque mode;
3 is an algorithm showing the operation of the speed control drive motor 10 operating in the speed mode,
4 is an algorithm illustrating an operation of the torque control driving motor 20 which is operated by converting to a speed mode when an emergency stop signal is input in the tension control device according to an embodiment of the present invention.
5A and 5B are graphs for comparing the existing method with respect to the effect of the tension control device according to an embodiment of the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Terms including ordinal numbers such as first and second may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

When a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that other components may be present in between. Should be. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, the terms "comprises" or "having" and the like refer to the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

In the following description of the present invention with reference to the accompanying drawings, the same components are denoted by the same reference numerals regardless of the reference numerals, and redundant explanations thereof will be omitted. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

1 is a view showing a basic environment in which the tension control device according to an embodiment of the present invention is used. As shown in FIG. 1, the control apparatus according to the exemplary embodiment includes a speed control driving motor 10 and a torque control driving motor 20. In addition, in FIG. 1, only two motors 10 and 20 are briefly shown because they are difficult to describe and represent a plurality of drive motors, and a mechanical device such as a nip-roll or a sensor, a control device, or a mechanical device for addition of a motor The device is shown uniaxially with reference numeral 50. On the other hand, each motor can measure the rotation speed using an encoder (encoder).

As shown in FIG. 1, the speed control drive motor 10 and the torque control drive motor 20 interlock to produce paper, fiber, film, steel products, and the like.

Here, the speed control drive motor 10 is a motor driven by controlling the linear speed of the motor, the torque control drive motor 20 is a motor driven by controlling the torque (torque). Here, the linear velocity is a term used to distinguish from the angular velocity and may be referred to as the length of the arc moved for a predetermined time.

Torque is a term commonly used in physics and can be referred to as the amount of pairing that rotates an object around a point. In other words, torque can also be referred to as the force that drives the engine.

Hereinafter, the operation of the motor operating in the speed mode and the torque mode will be described in detail with reference to FIGS. 2 and 3 through an algorithm.

2 is an algorithm showing the operation of the torque control drive motor 20 operating in the torque mode.

In the torque mode, first, when the induction motor 116 rotates, the speed detector 115 detects and outputs the rotation speed ω _r . The diameter calculating unit 107 receives the rotational speed ω _r detected by the speed detector 115 and the minimum diameter and linear speed command inputted from the outside. Equation 1 is a formula for calculating the diameter, and the calculated diameter is input to the command torque calculating unit 100 and used to calculate the command torque.

[Equation 1]

Where D is the diameter, rpm is the speed of the motor, and V is the linear speed command.

The command torque calculating unit 100 calculates the command torque using the diameter calculated by the diameter calculating unit 107 and the reference tension input from the outside, and Equation 2 is an equation for obtaining the command torque.

&Quot; (2) "

Where D _cur is the current computed diameter. The reference tension input from the outside through the third comparator 108 is compared with the actual tension (F _bk ), and goes through a PID to compensate for this output error. The output of the first adder 101 which adds the command torque calculated by the command torque calculating unit 100 and the output of the PID controller 109 becomes the torque current command value i ^{e *} _qs .

The torque current command value i ^{e *} _qs is input to the non-inverting terminal (+) of the first comparator 102, and the non-inverting terminal of the magnetic flux current command value (i ^{e *} _ds ) fmf comparator 117 is input from the outside. Enter as (+). The three-phase currents i _as , i _bs , and i _cs detected by the induction motor 116 are output as the fixed coordinate system two-phase currents i ^s _ds and i ^s _qs by the two-phase current converter 114. The fixed coordinate system two-phase currents i ^s _ds , i ^s _qs output from the two-phase current converter 114 are input to the current coordinate converter 113, so that the actual magnetic flux current i ^e _ds and torque current of the rotational coordinates ( i ^e _qs ) The magnetic flux currents ieds output from the current coordinate converter 113 are input to the inverting terminal (−) of the second comparator 117. Then, the second comparator 117 obtains an error between the magnetic flux current command value i ^{e *} _ds and the actual magnetic flux current i ^e _ds output from the current coordinate converter 113 and inputs it to the current controller 103. .

The first comparator 102 inputs the torque current command value i ^{e *} _qs output from the first adder 101 to the non-inverting terminal (+), and outputs the actual torque current output from the current coordinate converter 113. i ^e _qs ) is input to the inverting terminal (-), and the error between these two values can be obtained.

The current controller 103 which receives the torque component current output from the first comparator 102 and the magnetic flux current output from the second comparator 117 as input has a magnetic flux voltage command value v ^{e *} _ds and a torque voltage command value through control. (v ^{e *} _qs ) is output, and the output value is input to the voltage coordinate converter 104.

The voltage coordinate converter 104 outputs the magnetic flux voltage command value v ^{s *} _ds and the torque voltage command value v ^{s *} _qs , converts the three-phase voltage into v _as , v _bs , and v _cs , and controls the control inverter 106. )

The control inverter 106 rotates the induction motor 116 by applying three-phase voltages v _as , v _bs , and v _cs to the induction motor 116. The induction motor 116 is connected to the current coordinate converter 114. The two-phase current converter 113 generates the actual magnetic flux current (i ^e _ds ) and the torque current (i ^e _qs ) converted to the d-axis and q-axis by the actual rotation coordinates, and among the generated currents, the magnetic flux current (i ^e _ds ) is input to the second comparator 117, and the torque current i ^e _qs is input to the first comparator 102.

In addition, the slip calculator 110 includes a torque current command value i ^{e *} _qs output from the first adder 101, a flux current command value i ^{e *} _ds input from the outside, and an induction motor rotor time constant T. _r ) is used to calculate the slip frequency ω _sl . The slip frequency ω _sl can be obtained by the following equation.

&Quot; (3) "

The calculated slip frequency ω _sl is input to the integrator 112 in addition to the speed ω _r output from the speed detector 115. Integrator 112 is represented by 1 / s. The integrator 112 outputs the position θ of the rotor magnetic flux, which is an integral value with respect to the output value of the adder 111, which is input to the voltage coordinate converter 104 and the current coordinate converter 113.

Accordingly, the voltage coordinate converter 104 and the current coordinate converter 113 control the coordinate transformation according to the position θ of the rotor magnetic flux input to the integrator 112.

Through this coordinate transformation, torque is controlled to keep the line velocity constant and at the same time the tension on the material.

3 is an algorithm showing the operation of the speed control drive motor 10 operating in the speed mode. As shown in FIG. 3, in the case of the speed control drive motor 10 operating in the speed mode, a plurality of comparators, PID controllers, speed controllers, current controllers, phase shifters, and the like are based on command speeds and the like. It can be driven by controlling the linear velocity.

In the present invention, it is assumed that the emergency stop signal is drawn in during the operation in the torque mode. Thus, in order to provide a clear explanation within the scope of not obscuring the essence of the present invention, FIG. It will be described in detail with reference to.

4 is an algorithm illustrating an operation of a torque control driving motor 20 which is operated by converting to a speed mode when an emergency stop signal is input while operating in a torque mode in a tension control device according to an embodiment of the present invention. to be.

In the case of the tension control device used in the inverter application, when the motor receives the emergency stop signal, the speed control drive motor 10 driven in the speed mode stops within a certain time, and the motor driven in the torque mode is free run ( Although a control method of free-run is used, a tension control device according to an embodiment of the present invention shown in FIG. 4 is configured such that an emergency stop signal is input to a torque control drive motor 20 driven in a torque mode. In this case, since the driving is performed in the speed mode, the speed control driving motor 10 and the torque control driving motor 20 may be provided at the same time.

In order to more clearly describe the features of the present invention with reference to FIG. 4, first, a case where an emergency stop signal is not input will be described first, and then a case where an emergency stop signal is input will be described.

When the emergency stop signal is not input, the internal switch of the emergency stop device 224 is turned to 2, which means to drive the torque control drive motor 20 in the torque mode.

When the induction motor 216 rotates in the torque mode, the speed detector 215 detects the rotation speed ω _r and outputs it.

The diameter calculating unit 207 receives the rotational speed omega _r detected by the speed detector 215 and the minimum diameter and linear velocity command input from the outside. The equation for calculating the diameter is the same as that of Equation 1, and the calculated diameter is input to the command torque calculator 208 and used to calculate the command torque. The torque command calculating unit 200 calculates the command torque using the diameter calculated by the diameter calculating unit 207 and the reference tension input from the outside. The equation for obtaining the command torque is the same as that in Equation 2 above.

The reference tension input from the outside through the third comparator 208 and the actual tension (F _bk ) is compared, and passes through the PID controller 209 to compensate for this output error.

Since the command torque calculated by the command torque calculating unit 200 and the PID controller 209 should have an I-term regardless of the input of the emergency stop signal, both cases of receiving the command speed and receiving the command torque are required. Indicated.

The torque current command value i ^{e *} _qs is input to the non-inverting terminal (+) of the first comparator 202, and the magnetic flux current command value i ^{e *} _ds is input from the second comparator i ^s _ds , i. ^s _qs ) as the non-inverting terminal (+).

The three-phase currents i _as , i _bs , i _cs detected by the induction motor 216 are output by the two-phase current converter 214 as fixed coordinate two-phase currents i ^s _ds , i ^s _qs . The fixed coordinate system two-phase current i ^s _ds , i ^s _qs output from the two-phase current converter 214 is input to the current coordinate converter 213 to input the actual magnetic flux current i ^e _ds and the torque current i of the rotational coordinates. ^e _qs )

The magnetic flux current i ^e _ds output from the current coordinate converter 213 is input to the inverting terminal (−) of the second comparator 217. Then, the second comparator 217 obtains an error between the flux current command value i ^{e *} _ds input from the outside and the actual flux current i ^e _ds output from the current coordinate converter 213 to the current controller 203. Is entered.

The first comparator 202 inputs the torque current command value i ^{e *} _qs output from the first adder 201 to the non-inverting terminal (+), and outputs the actual torque current output from the current coordinate converter 213. (i ^e _qs ) is input to the inverting terminal (-) to obtain an error between these two values.

The current controller 203 that receives the torque component current output from the first comparator 202 and the magnetic flux current output from the second comparator 217 as an input controls the magnetic flux voltage command value v ^{e *} _ds and the torque voltage. The command value v ^{e *} _qs is output, and the output value is input to the voltage coordinate converter 204.

The voltage coordinate converter 204 outputs the magnetic flux voltage command value (v ^{s *} _ds ) and the torque voltage command value (v ^{s *} _qs ), and the three-phase voltage (v _as , v _bs , v) through the three-phase voltage converter 205. _cs ) to provide to the control inverter 206.

The control inverter 206 causes the induction motor 216 to rotate by applying the three-phase voltages v _as , v _bs , and v _cs to the induction motor 216. Induction motor 216 is the actual magnetic flux current (i ^e _ds ) and torque current (i ^e _qs ) converted to the d-axis and q-axis in the actual rotation coordinates through the current coordinate converter 214 and the two-phase current converter 213 The magnetic flux current i ^e _ds of the generated current is input to the second comparator 217, and the torque current i ^e _qs is input to the first comparator 202.

In addition, the slip calculator 210 includes a torque current command value i ^{e *} _qs output from the first adder 201, a flux current command value i ^{e *} _ds input from the outside, and an induction motor rotor time constant T. _r ), the slip frequency ω _sl is calculated.

The calculated slip frequency ω _sl is input to the integrator 212 in addition to the speed ω _r output from the speed detector 215. The integrator 212 outputs the position θ of the rotor magnetic flux, which is an integral value with respect to the output value of the adder 211, which is input to the voltage coordinate converter 204 and the current coordinate converter 213. Accordingly, the voltage coordinate converter 204 and the current coordinate converter 213 control the coordinate transformation according to the position θ of the rotor magnetic flux input to the integrator 212. By controlling the torque through such coordinate transformation, the tension control device operates while maintaining a constant linear velocity while maintaining a constant linear velocity.

On the other hand, when the emergency stop signal is input, the internal switch of the emergency stop device 224 is directed to 1, and the torque control drive motor driven in the torque mode is driven in the speed mode.

In order to operate the motor in the speed mode, a third comparator 208 compares the reference tension input from the outside with the actual tension F _{bk and} passes through the PID controller 209 to compensate for the output error. .

The output value of the PID controller 209 is the speed detector 215 for detecting the rotation speed of the first adder 218 and the induction motor 216, the rotation speed omega _r detected by the speed detector 215, and the adder. Compare the command value (ω ^* _r ) output from 218. The speed controller 220 outputs the torque current command value i ^{e *} _qs for compensating the speed error output from the first comparator 219.

The input of the speed controller 220 is a value obtained by comparing the torque current command value i ^{e *} _qs with the actual torque current i ^e _qs as the output of the second comparator 222. The magnetic flux to be input from an external current command value (i ^{e *} _ds) from the original and output flux current third comparator 223 for outputting by comparing (i ^e _ds), the torque current outputted from the second comparator 222 is It enters the input of the current controller 203, through which the magnetic flux voltage command value (ve ^{e *} _ds ) and torque voltage command value ( _ve ^{e *} _qs ) is output.

The output of the current controller 203 is converted from the rotational coordinates to the fixed coordinates through the voltage coordinate converter 204, and the flux voltage command value (v ^{s *} _ds ) and torque voltage command value (v ^{s *} _qs ) converted to the fixed coordinates. Is output _as v _as , v _bs , and v _cs through the three-phase voltage converter 205.

Three-phase voltages v _as , v _bs , and v _cs of fixed coordinates are applied to the control inverter 206 to rotate the induction motor 216. The three-phase currents i _as , i _bs , i _cs detected when the induction motor 216 rotates are converted into the d-axis and q-axis of the fixed coordinate system through the two-phase current converter 214 to i ^s _ds , i ^s _qs . and the converted i _ds ^{s, s} i _qs values are converted to the actual current of the magnetic flux rotating coordinate (i _ds ^e) and the torque current (i _qs ^e) through the current coordinate converter (213).

The slip calculator 221 receives the torque current command value i ^{e *} _qs output from the speed controller 220 and the magnetic flux current command value i ^{e *} _ds input from the outside and receives the induction motor rotor time constant T _r . Calculate the slip frequency (ω _sl ) using.

The slip frequency ω _sl may be obtained in the same manner as in Equation 3 above. The slip frequency ω _sl calculated by the slip calculator 221 is added through the second adder 211 together with the speed detector 215, and the added value is integrated through the integrator 212 to position the rotor magnetic flux. Let (θ) be known. Coordinate transformation is controlled according to the position of the rotor magnetic flux, thereby providing a tension control device which maintains a constant linear velocity and at the same time a tension applied to the material.

In other words, in the case of the tension control device according to an embodiment of the present invention, when the emergency stop signal is not input, the switch of the emergency stop device 224 is connected to 2 and the torque control drive motor in the conventional torque mode ( 20), when the emergency stop signal is input, the switch of the emergency stop device 224 is connected to 1 to rotate the torque control drive motor 20 in the speed mode.

5A and 5B are graphs for comparing the existing method with respect to the effect of the tension control device according to an embodiment of the present invention.

5A illustrates a case where an emergency stop signal is input in a conventional tension control device. In FIG. 5A, reference numeral 300 denotes a graph showing the operation of the speed control driving motor when the emergency stop signal is input at the time t1, and reference numeral 310 denotes the operation of the torque control driving motor when the emergency stop signal is input at the time t1. Graph showing the action. In FIG. 5A, the horizontal axis represents time and the vertical axis represents speed.

When the emergency stop signal is input t1 in the existing tension control device as shown by reference numeral 300, the speed control drive motor operating in the speed mode is constantly reduced in time between t1 and t2 to stop.

However, when the emergency stop signal is input t1 in the existing tension control device as indicated by reference numeral 310, the torque control drive motor operating in the torque mode free-runs to freely rotate and slowly stops.

As such, when the emergency stop signal is input, the two motors operate in different aspects to stop each other, which may cause serious damage to the system, and may cause material damage or sagging.

5B illustrates a case where an emergency stop signal is input in the tension control device according to an embodiment of the present invention. In FIG. 5B, reference numeral 400 denotes a graph showing the operation of the speed control driving motor when the emergency stop signal is input at the time t1, and reference numeral 410 denotes the operation of the torque control driving motor when the emergency stop signal is input at the time t1. It is a graph. In FIG. 5B, the horizontal axis represents time and the vertical axis represents speed.

When the emergency stop signal is input t1 in the tension control device according to the exemplary embodiment of the present invention as shown by reference numeral 400, the speed control drive motor operating in the speed mode decreases and stops for a time between t1 and t2. .

When the emergency stop signal is input t1 in the tension control device according to the exemplary embodiment of the present invention as shown by reference numeral 410, the torque control drive motor operating in the torque mode also operates in the speed mode, and thus, between t1 and t2. Constantly decreases over time and stops.

That is, when the emergency stop signal is input in the tension control device according to an embodiment of the present invention, unlike the conventional two motors can be stopped at the same time.

This not only prevents the breakage or sagging of the material, but also makes it possible to use more sensitive materials than previously used materials.

In the foregoing description, each component and / or function described in various embodiments may be implemented in combination with each other, and those skilled in the art may recognize the present invention described in the claims below. It will be understood that various modifications and variations can be made in the present invention without departing from the spirit and scope.

10 ........................... Speed Control Drive Motor
20 ........................... Torque Control Drive Motor

Claims (5)

In the tension control device operating in the speed mode and the torque mode,
A speed control drive motor operating in the speed mode; And
A torque control drive motor operating in the torque mode;
And when an emergency stop signal is input during operation in the torque mode, the torque control drive motor converts from the torque mode to the speed mode to operate the tension control device. The method of claim 1,
The speed mode is
A tension control device, characterized in that the motor is rotated by controlling the linear speed of the speed control drive motor or the torque control drive motor. The method of claim 1,
The torque mode is,
And a mode for controlling the torque of the speed control drive motor or the torque control drive motor to operate the motor. The method of claim 1,
And a emergency stop device for receiving the emergency stop signal from a user. The method of claim 1,
And said speed control drive motor and said torque control drive motor are motors for rotating a cylinder.

Images