CN1103650C - Roll stand drive arrangement - Google Patents
Roll stand drive arrangement Download PDFInfo
- Publication number
- CN1103650C CN1103650C CN97180408A CN97180408A CN1103650C CN 1103650 C CN1103650 C CN 1103650C CN 97180408 A CN97180408 A CN 97180408A CN 97180408 A CN97180408 A CN 97180408A CN 1103650 C CN1103650 C CN 1103650C
- Authority
- CN
- China
- Prior art keywords
- drive unit
- current transformer
- power
- alternating voltage
- designed
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
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Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/483—Converters with outputs that each can have more than two voltages levels
- H02M7/487—Neutral point clamped inverters
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/46—Roll speed or drive motor control
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/18—Arrangements for adjusting, eliminating or compensating reactive power in networks
- H02J3/1892—Arrangements for adjusting, eliminating or compensating reactive power in networks the arrangements being an integral part of the load, e.g. a motor, or of its control circuit
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P2207/00—Indexing scheme relating to controlling arrangements characterised by the type of motor
- H02P2207/07—Doubly fed machines receiving two supplies both on the stator only wherein the power supply is fed to different sets of stator windings or to rotor and stator windings
- H02P2207/076—Doubly fed machines receiving two supplies both on the stator only wherein the power supply is fed to different sets of stator windings or to rotor and stator windings wherein both supplies are made via converters: especially doubly-fed induction machines; e.g. for starting
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/10—Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Mechanical Engineering (AREA)
- Inverter Devices (AREA)
- Control Of Ac Motors In General (AREA)
Abstract
The invention concerns a drive arrangement for industrial plants, in particular for plants used in the primary industry, said arrangement having at least one electric motor and at least one converter via which the electric motor is connected to an alternating voltage electricity supply system. The converter regulates the active-power input, rotational speed and torque of the electric motor, the converter being designed so as to feed adjustable reactive power into the alternating voltage electricity supply system.
Description
The present invention relates to a kind of roll stand drive arrangement.
To the industrial electrical network of large-scale drive unit power supply, for example be used for the alternating voltage power supply network of rolling mill, load has very big inductance type reactive power.This has caused local pressure drop and high transmission loss.Especially light current net and this situation can occur away from the electrical network of generator.Knownly can solve this problem by the reactive power compensating apparatus of costliness, this compensation equipment adds the stabilizer (thyristor adjuster and reactor) that is conditioned by the capacitor workbench that is switched on and under may situation and forms.
The object of the present invention is to provide a kind of drive unit, can obtain a kind of simple, cheap reactive power compensation with it.
The objective of the invention is to realize by the described a kind of drive unit of claim 1.Therefore this drive unit has at least one alternating current motor and at least one current transformer, alternating current motor is connected with an alternating voltage power supply network through this current transformer, wherein this current transformer is controlled the effective power that this alternating current motor obtains from the alternating voltage power supply network, and power supply property ground forms adjustable, an especially capacitive reactive power in the alternating voltage power supply network.Can avoid adopting the compensation equipment of the costliness that is used for drive unit thus.
In the form of implementation with advantage of the present invention, drive unit designs like this: it compensates that at least one is connected with the alternating voltage power supply network, as to produce the device of reactive power inductive and/or capacitive character reactive power.This is a form of implementation that has advantage especially, is connected with the alternating voltage power supply network because can not adopt like this, is used for reactive power compensation device, especially driver that other produces the costliness of reactive power device.Can conceive by this way be used for industrial equipment, in particular for the dog-cheap drive unit of milling train.
In the other arrangement form with advantage of the present invention, drive unit is designed like this: it comes compensating power according to the first-harmonic of the alternating voltage of alternating voltage power supply network.
In another arrangement form with advantage of the present invention, drive unit is designed like this: the one or more harmonic components according to the alternating voltage of alternating voltage power supply network compensate the star reactive power, so also can cancel the filter workbench that is used for the compensation harmonic component.
One has in the arrangement form of advantage coupling circuit voltage calculation element in the middle of drive unit has, coupling circuit voltage in the middle of it calculates according to the voltage of alternating voltage power supply network again of the present invention.
Have especially advantage be to use according to of the present invention being used for be to work in the power bracket of 2～10MW at a 1～20MW, primely, or relevantly be used for one 2～30MW, be the drive unit of shock loading of the power bracket of 4～20MW primely.
Drive unit of the present invention is proving particularly advantageous aspect the alternating current motor that is used to connect, that is in such circuit, wherein alternating current motor has the open circuit winding, and these windings are two-way powers by current transformer.
Drive unit of the present invention can be particularly advantageous for driving the rolling-mill housing of a milling train in addition.
Drive unit of the present invention also can particularly advantageously be used to support power supply network voltage by the reactive power feed-in.
The current transformer of drive unit of the present invention also can be implemented as air-cooled current transformer in addition.
Other advantage of the present invention and details can be understood by following description to embodiment with reference to the accompanying drawings and in conjunction with dependent claims.In the accompanying drawing:
Figure 1 shows that drive unit of the present invention,
Figure 2 shows that an adjusting device that is used for drive unit of the present invention,
Figure 3 shows that a converter device, be used for alternating current motor power supply minute converter that has connection in 3 o'clock in one of electrical network and machine side,
Figure 4 shows that a converter device, be used for an AC electrical device with open circuit winding with minute converter of connection in 3 o'clock is made bidirectional power supply.
Fig. 5 illustrates and will be used for a milling train according to current transformer of the present invention.
Fig. 1 illustrates one according to drive unit of the present invention, and it has an alternating current motor 6, and this alternating current motor 6 links to each other with a power supply network 1 with a transformer 2 or a reactor through a current transformer.This current transformer has a rectifier 3 of controlling automatically, a direct current voltage intermediate circuit 4 and a vibrapack 5 of control automatically.Alternating current motor 6 is regulated by an adjusting device 7 from the power that power supply network 1 obtains.The needed voltage intermediate circuit rated voltage of one vibrapack U is provided for this adjusting device for this reason
* ZK, be used to adjust torque, rotating speed and/or the power of alternating current motor 6.Adjusting device 7 following adjustings are the rectifier of control automatically, makes to have an intermediate circuit voltage U at its output
ZK, this voltage U
ZKCorresponding to desired intermediate circuit rated voltage U
* ZKIn addition, also be adjusting device 7 inputs one reactive power rated value Q
*Adjusting device 7 is regulated the rectifier 3 of automatic control like this, makes it provide a reactive power to power supply network 1, and this reactive power is corresponding to the rated reactive power Q of expectation
*In the exemplary form of implementation according to Fig. 1, drive unit of the present invention has one and is used for predetermined reactive power value Q
*Device 9.This device 9 is advantageously predesignated a reactive power rated value Q
*, this rated value Q
*Cause the output of a reactive power of drive unit of the present invention, the reactive power output of the device 8 of the generation reactive power of this reactive power output compensation on power supply network 1.Drive unit of the present invention thus can not only compensate the reactive power according to the alternating voltage first-harmonic of power supply network 1, and can compensate its high-frequency harmonic component.
Fig. 2 illustrates an exemplary detailed arrangement form of adjusting device 7 shown in Figure 1.This adjusting device 7 has an intermediate circuit voltage adjuster 10, an effective current adjuster 11, a reactive current preset device 12, a reactive current adjuster 13, a control device 14 and a measured value processor 15 in this exemplary arrangement.Intermediate circuit voltage adjuster 10 is from middle circuit rated voltage U
* ZKAnd intermediate circuit voltage U
ZKIn try to achieve a rated value I who is used for effective current
* wReactive power preset device 12 is from reactive power rated value Q
*In try to achieve a reactive current rated value I
* BEffective current adjuster 11 is from effective current rated value I
* wWith effective current actual value I
wMiddle generation one is used for the rated value of the voltage between transformer 2 and the automatic rectifier of controlling 3.Wattless current adjuster 13 is from reactive current set point I
* BWith reactive current actual value I
BIn also produce the rated value of the voltage between the rectifier 3 be used for transformer 2 and control automatically.The output of effective current adjuster 11 and reactive current adjuster 13 is transfused to a control device 14, this control device 14 produces in this wise and is used for the control signal of the power semiconductor of the rectifier 3 of control automatically, makes desirable voltage result from the AC side of the rectifier 3 of automatic control.
In having the arrangement form of advantage, the output of effective current adjuster 11 and reactive current adjuster 13 is added through control device 14.Effective current actual value I
w, reactive current actual value I
B, and intermediate circuit voltage U
ZKMeasured or advantageously be determined by a measured value processor 15.This processor 15 by power supply network 1 electric current and the current measurement value of orientation between the rectifier 3 of transformer 2 and control automatically of the phase place of voltage try to achieve effective current I
wWith reactive current I
B
Be used to predesignate reactive power rated value Q
*Device 9 by for example the electric current of alternating voltage power supply network 1 and the measurement of voltage being tried to achieve this rated value Q
*In the alternative arrangements form, be used to predesignate reactive power rated value Q
*Device 9 in from given data, try to achieve reactive power demand or an amount of equal value with it to the device that links to each other with power supply network.In particularly advantageous arrangement form, be used to predesignate reactive power rated value Q
*Device 9 be connected with higher level's control system, perhaps the part with a kind of like this control system links to each other, and with to trying to achieve the reactive power demand in the data that are connected device on the alternating voltage power supply network 1 and their operating state.So for example a plurality of just can have a single reactive power rated value Q who is used to predesignate them according to drive unit of the present invention
*Device 9.
Fig. 3 illustrates a converter device that is used for alternating current motor power supply, and wherein the branch current transformer 34 of the branch current transformer 33 of grid side and motor side is designed to identical and has GTO (gate circuit disconnecting apparatus) with 3 connections.The main current loop of a phase place assembly shown in it and routing network 40 or 41.Divide current transformer 33 and 34 to have three such phase place assemblies separately.The intermediate circuit 37 of positive terminal is formed dc voltage intermediate circuit with the intermediate circuit 39 of negative pole end, through this intermediate circuit two fens current transformers is connected.The wiring feedback resistance 36 of positive terminal and the wiring feedback resistance 38 of negative pole end are connected with a corresponding side of routing network 40 or 41.
The branch current transformer 33 of grid side is connected with electrical network 30 with power switch device 32 by transformer 31 at output.The branch current transformer 34 of motor one side is connected with alternating current motor 35 at output.
In the collocation form of Fig. 4, first current transformer 74 and second current transformer 75 are connected with 72 with a side 71 of open circuit three phase windings of alternating current motor 73 respectively at its output., power also can obtain a particularly advantageous operating characteristic one times except being increased by this configuration, because according to the pulse method of adjusting in advance, only when the low switching frequency of GTO thyristor, just on motor, reached one and be sine-shaped, as to have less harmonic component electric current change curve to a great extent.
First current transformer 74 for example is connected with power supply network 60 with the star/delta connection method with first transformer 61 by an additional inductor 63 that is chosen in grid side in grid side.Second current transformer 75 advantageously is connected with power supply network 60 with respect to 30 ° of ground, angle of the first transformer deflection (for example adopting star/Y-connection method) with second transformer 62 by an additional inductor 64 that is chosen in grid side.Especially when current transformer is made up of the branch current transformer that connects by the triangle connection method (as described in present embodiment), can produce particularly advantageous network-feedback to electrical network by such layout.Under these circumstances, even if at the first-harmonic of the automatic electrical network current transformer of control in the pulse period, also can to cause the electric current change curve be sinusoid and only have very little harmonic component.
Two current transformers 74 and 75 each comfortable grid side have branch current transformer 66 or 65 and have branch current transformer 69 or 70 separately at motor side, and they are respectively hung oneself and flow voltage intermediate circuit 67 or 68 always and be connected.Two dc voltage intermediate circuits 67 or 68 are electric each other separately.All divide current transformer 66,65,69,70 to be designed to 3 connections, preferably have RC gate circuit decoupler.
Fig. 5 illustrates equipment of the present invention is applied to a milling train.Rolled piece 103 is rolled in rolling-mill housing 104,105,106,107, and above-mentioned mill stand is 99,100,101,102 drivings of electromotor.Respectively a hang oneself transformer 91,92,93,94 and a current transformer 95,96,97,98 of motor 99,100,101,102 powered by a power supply network 90.In a possible embodiment, transformer 91, current transformer 95 and alternating current motor 99 are the part of drive unit of the present invention, and this drive unit compensation is by the reactive power that drive unit produced of other rolling-mill housing 105,106,107.The shared ratio of drive unit that is used for compensating power of the present invention and known drive unit is fully according to the demand of capacitive character reactive power is decided, so that compensate the inductive reactive power of common drive unit.
What have bigger meaning concerning reality is a kind of form of implementation, wherein the All Drives of a milling train is all designed and compensates the reactive power of the driver of other milling train according to the present invention.
Claims (10)
1. drive unit that is used for rolling-mill housing, it has at least one motor and at least one has the current transformer of power semiconductor, by this current transformer this motor is connected with an alternating voltage power supply network, wherein this current transformer is regulated effective power consumption or the rotating speed and/or the torque of motor, it is characterized in that: this drive unit has an adjusting device (7), regulate or the power controlling semiconductor device with this adjusting device (7), make current transformer with an adjustable reactive power feed-in alternating voltage power supply network, wherein, adjusting device (7) has a reactive current preset device (12) and a measured value processor (15).
2. drive unit as claimed in claim 1 is characterized in that: described drive unit is designed to compensate the reactive power that at least one produces the device (8) of reactive power, and this device (8) is connected with the alternating voltage power supply network.
3. drive unit as claimed in claim 2 is characterized in that: described drive unit is designed to come compensating power according to the first-harmonic of alternating voltage power supply network alternating voltage.
4. as claim 2 or 3 described drive units, it is characterized in that: described drive unit is designed to come compensating power according to one or more harmonic componentss of alternating voltage power supply network alternating voltage.
5. as the described drive unit of above-mentioned each claim, it is characterized in that: this drive unit has one and predesignates the device (9) of a reactive power rated value according to the reactive power of required feed-in alternating voltage power supply network.
6. as the described drive unit of above-mentioned each claim, it is characterized in that: described current transformer is designed to have the current transformer of taking three point-connected dc voltage intermediate circuits.
7. as each described drive unit in the claim 1 to 5, it is characterized in that: described current transformer is designed to have the current transformer of the dc voltage intermediate circuit of taking the connection of n point, and wherein n is more than or equal to 2.
8. as each described drive unit in the claim 1 to 7, it is characterized in that: the described power semiconductor that cuts off is designed to the GTO device, that is is formed gate circuit disconnection thyristor.
9. as each described drive unit in the claim 1 to 7, it is characterized in that: described current transformer has the power semiconductor that can cut off, and they are designed to power transistor, especially IGBT device, that is igbt.
10. as each described drive unit in the claim 1 to 9, it is characterized in that: the described power semiconductor that cuts off is designed to reverse-conducting.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19653182.9 | 1996-12-20 | ||
| DE19653182A DE19653182A1 (en) | 1996-12-20 | 1996-12-20 | Drive device for roll stands |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1239909A CN1239909A (en) | 1999-12-29 |
| CN1103650C true CN1103650C (en) | 2003-03-26 |
Family
ID=7815461
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN97180408A Expired - Fee Related CN1103650C (en) | 1996-12-20 | 1997-12-09 | Roll stand drive arrangement |
Country Status (4)
| Country | Link |
|---|---|
| CN (1) | CN1103650C (en) |
| AT (1) | AT410184B (en) |
| DE (2) | DE19653182A1 (en) |
| WO (1) | WO1998028095A1 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6798159B1 (en) * | 2003-04-14 | 2004-09-28 | Carrier Corporation | VSD control |
| WO2009134770A1 (en) * | 2008-04-28 | 2009-11-05 | Abb Research Ltd. | Apparatus and method for increasing efficiency in power generation plants |
| US9300131B2 (en) | 2009-06-01 | 2016-03-29 | Abb Research Ltd. | Internal electrification scheme for power generation plants |
| EP2438668A2 (en) * | 2009-06-01 | 2012-04-11 | ABB Research Ltd. | Improved internal electrification scheme for power generation plants |
| CA2832888A1 (en) * | 2011-04-14 | 2013-10-18 | Harold Wells Associates, Inc. | Electrical apparatus and control system |
| DE102012210138A1 (en) * | 2012-06-15 | 2013-12-19 | Siemens Aktiengesellschaft | Energy supply system for supplying electrical consumers in rail vehicles |
| EP2689864A1 (en) * | 2012-07-27 | 2014-01-29 | Siemens Aktiengesellschaft | Method for processing milled goods in a rolling mill |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4914375A (en) * | 1988-06-08 | 1990-04-03 | Arex Electronics Corporation | Saturable reactor apparatus for automatic control of power factor of inductive load |
| JPH06198318A (en) * | 1993-01-07 | 1994-07-19 | Hitachi Ltd | System for controlling rolling |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3725515C2 (en) * | 1987-07-29 | 1995-02-09 | Licentia Gmbh | Quenching procedure for controllable power converters |
| AT397321B (en) * | 1989-09-11 | 1994-03-25 | Elin Union Ag | CIRCUIT ARRANGEMENT FOR A CONTROLLED INVERTER |
| DE58907858D1 (en) * | 1989-09-11 | 1994-07-14 | Siemens Ag | METHOD AND DEVICE FOR DETECTING RESONANCE MEASURES OF A NETWORK CONNECTED TO A RECTIFIER. |
| JP2954333B2 (en) * | 1990-11-28 | 1999-09-27 | 株式会社日立製作所 | AC motor variable speed system |
| JPH04255427A (en) * | 1991-02-05 | 1992-09-10 | Toyo Electric Mfg Co Ltd | Compensator for higher harmonic and reactive power |
| JP2760666B2 (en) * | 1991-03-15 | 1998-06-04 | 株式会社東芝 | Method and apparatus for controlling PWM converter |
| JPH0844447A (en) * | 1993-07-01 | 1996-02-16 | Toshiba Corp | Self-excited static type reactive power compensating device |
| JP3352182B2 (en) * | 1993-11-09 | 2002-12-03 | 三菱電機株式会社 | Inverter device |
| GB2285523B (en) * | 1994-01-08 | 1997-10-15 | Gec Alsthom Ltd | Improvements in or relating to multilevel convertors |
-
1996
- 1996-12-20 DE DE19653182A patent/DE19653182A1/en not_active Ceased
-
1997
- 1997-12-09 WO PCT/DE1997/002865 patent/WO1998028095A1/en active Application Filing
- 1997-12-09 DE DE19781466T patent/DE19781466D2/en not_active Ceased
- 1997-12-09 CN CN97180408A patent/CN1103650C/en not_active Expired - Fee Related
- 1997-12-09 AT AT0912297A patent/AT410184B/en not_active IP Right Cessation
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4914375A (en) * | 1988-06-08 | 1990-04-03 | Arex Electronics Corporation | Saturable reactor apparatus for automatic control of power factor of inductive load |
| JPH06198318A (en) * | 1993-01-07 | 1994-07-19 | Hitachi Ltd | System for controlling rolling |
Also Published As
| Publication number | Publication date |
|---|---|
| DE19781466D2 (en) | 1999-09-23 |
| ATA912297A (en) | 2002-07-15 |
| WO1998028095A1 (en) | 1998-07-02 |
| CN1239909A (en) | 1999-12-29 |
| AT410184B (en) | 2003-02-25 |
| DE19653182A1 (en) | 1998-06-25 |
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| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20030326 Termination date: 20121209 |