CN102969719B - Be applicable to the intelligence filter harmonic energy saving device of intermediate frequency furnace - Google Patents
Be applicable to the intelligence filter harmonic energy saving device of intermediate frequency furnace Download PDFInfo
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- CN102969719B CN102969719B CN201210553934.9A CN201210553934A CN102969719B CN 102969719 B CN102969719 B CN 102969719B CN 201210553934 A CN201210553934 A CN 201210553934A CN 102969719 B CN102969719 B CN 102969719B
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- 239000003990 capacitor Substances 0.000 claims abstract description 23
- 238000012544 monitoring process Methods 0.000 claims description 12
- 230000005540 biological transmission Effects 0.000 claims description 5
- 238000006243 chemical reaction Methods 0.000 claims description 4
- 238000001914 filtration Methods 0.000 abstract description 9
- 230000008901 benefit Effects 0.000 abstract description 2
- 230000008878 coupling Effects 0.000 abstract description 2
- 238000010168 coupling process Methods 0.000 abstract description 2
- 238000005859 coupling reaction Methods 0.000 abstract description 2
- 230000008030 elimination Effects 0.000 description 3
- 238000003379 elimination reaction Methods 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000005272 metallurgy Methods 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- 230000004075 alteration Effects 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
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- 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
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/30—Reactive power compensation
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- 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
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/40—Arrangements for reducing harmonics
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Abstract
The invention discloses a kind of intelligence filter harmonic energy saving device being applicable to intermediate frequency furnace, it is characterized in that, comprise: harmonic main frame, the first/bis-contactor, reactor, capacitor, intermediate frequency power supply, instrument transformer and programmable controller, aforementioned harmonic main frame is connected with intermediate frequency power supply, in parallel with the first contactor, export tap and be connected with LC filtering compensation loop, V line is also connected with instrument transformer; Aforementioned programmable controller one end is connected with instrument transformer, the other end is connected on the control coil of the second contactor.Usefulness of the present invention is: by the second contactor control connection reactor and capacitor by programmable controller Based Intelligent Control in the output tap of harmonic main frame, provide the flow-guiding channel of an intelligent harmonic wave, the a large amount of harmonic waves produced by intermediate frequency power supply are cancelled out each other by the coupling of reactance and electric capacity, simultaneously, both the merit of capacitor can having been avoided because crossing benefit phenomenon, the problem that capacitor frequently switches can have been avoided again.
Description
Technical field
The present invention relates to a kind of filter harmonic device, be specifically related to a kind of intelligence filter harmonic device that is energy-conservation, that be applicable to intermediate frequency furnace.
Background technology
Along with metallurgy industry by the blast furnace (furnace cupola) of fire coal to the transformation of electric furnace, particularly intermediate frequency furnace is in the application of metallurgy industry, the intermediate frequency power supply of a large amount of intermediate frequency furnaces is in the process of carrying out frequency translation, current distortion rate reaches about 30%, voltage distortion rate about 10%, the conversion of electric current can cause power network current to distort, affect the power supply quality of electrical network, thus make the decline of mains supply quality, the increase of electrical network supplementary load loss, also can cause the power consumption equipment loss increase in netting, the lost of life simultaneously, have a strong impact on the normal work of periphery electrical equipment.
The improvement of current intermediate frequency furnace harmonic pollution, mainly take passive filter, junction filter and active filter three kinds of modes, equal parallel connection in the line.In these three kinds of modes, first two can only be administered 5 times and 7 subharmonic targetedly, after its harmonic wave control, current distortion rate reaches about 15%, harmonic current still can not reach the requirement of 12%, substantially regulation effect is not had to harmonic voltage, more can not meet the standard-required being less than 5%, can not effective harmonic carcellation; Although active power filtering mode good wave filtering effect, after harmonic elimination, harmonic content accounts for about 10%, there is the shortcomings such as expensive, failure rate is high, volume is large.
In addition, also there is the low problem of power factor in many domestic intermediate frequency furnaces, when adopting reactive power compensation, because intermediate frequency furnace load variations is relatively more frequent, so, capacitor automatic switching can be caused to act frequently, capacitor influence from harmonic is large, impulse current, and life-span, capacity attenuation are fast.
Summary of the invention
For solving the deficiencies in the prior art, the object of the present invention is to provide a kind of harmonic wave effectively can eliminated intermediate frequency furnace equipment and produce when frequency translation, and the filter harmonic energy saving device of surge current suppression, raising power factor (PF), guarantee electrical network quality, and this filter harmonic device can realize Based Intelligent Control to capacitor switching.
In order to realize above-mentioned target, the present invention adopts following technical scheme:
A kind of intelligence filter harmonic energy saving device being applicable to intermediate frequency furnace, it is characterized in that, comprise: harmonic main frame, the first contactor, the second contactor, reactor, capacitor, intermediate frequency power supply, instrument transformer and programmable controller, the input of aforementioned harmonic main frame is connected with three phase mains, output is connected with intermediate frequency power supply; Aforementioned first contactor is in parallel with harmonic main frame; The output of aforementioned reactor is connected with capacitor, input is connected with the second contactor, and the input of the second contactor is connected with the output tap of harmonic main frame again, and aforementioned capacitor inside adopts the wiring of triangle connected mode; The output of harmonic main frame have U V W tri-lines, aforementioned instrument transformer is connected on V line; The input of aforementioned programmable controller is connected with instrument transformer, output switch is connected on the control coil of the second contactor.
The aforesaid intelligence filter harmonic energy saving device being applicable to intermediate frequency furnace, it is characterized in that, aforementioned reactor is three-phase tuning reactor.
Preferably, the reactance Rate of aforementioned three-phase tuning reactor is 5-16%.
More preferred, the reactance Rate of aforementioned three-phase tuning reactor is 7%.
The aforesaid intelligence filter harmonic energy saving device being applicable to intermediate frequency furnace, it is characterized in that, aforementioned intermediate frequency power supply is the intermediate frequency power supply of three-phase six impulse commutation.
The aforesaid intelligence filter harmonic energy saving device being applicable to intermediate frequency furnace, it is characterized in that, also comprise: electric power monitoring instrument, the voltage sample line of aforementioned electric power monitoring instrument is connected on the input of harmonic main frame, current sample line is by access after instrument transformer conversion, and aforementioned instrument transformer is through on the output of three phase mains.
Preferably, aforementioned electric power monitoring instrument has data transmission module.
Usefulness of the present invention is: the harmonic current that harmonic main frame of connecting before intermediate frequency power supply can effectively stop intermediate frequency furnace to produce and harmonic voltage are to electrical grid transmission, then pass through in the output tap of harmonic main frame by the second contactor control connection reactor and capacitor of programmable controller Based Intelligent Control, form LC filter circuit, can provide the flow-guiding channel of an intelligent harmonic wave, a large amount of harmonic waves produced by intermediate frequency power supply are cancelled out each other by the coupling of reactance and electric capacity; While cancelling out each other, both can avoid because of filtering capacitor intermediate frequency furnace not the operating time phase devote oneself to work and the merit that causes because crossing benefit phenomenon, the problem because merit causes capacitor frequently to switch because of control mode can be avoided again.
Accompanying drawing explanation
Fig. 1 is the electrical block diagram that the present invention is applicable to a specific embodiment of the intelligence filter harmonic energy saving device of intermediate frequency furnace;
Fig. 2 (a) and (b) are install voltage, the current waveform figure that the present invention filters intermediate frequency furnace before harmonic device additional respectively;
Fig. 3 (a) and (b) are install voltage, the current waveform figure that the present invention filters intermediate frequency furnace after harmonic device additional respectively;
The implication of Reference numeral in figure: 1-harmonic main frame, 2-first contactor, 3-second contactor, 4-reactor, 5-capacitor, 6-intermediate frequency power supply, 7-instrument transformer, 8-programmable controller, 9-electric power monitoring instrument, 10-three phase mains.
Embodiment
Below in conjunction with the drawings and specific embodiments, concrete introduction is done to the present invention.
With reference to Fig. 1, the intelligence filter harmonic energy saving device being applicable to intermediate frequency furnace of the present invention comprises: harmonic main frame 1, first contactor 2, second contactor 3, reactor 4, capacitor 5, intermediate frequency power supply 6, instrument transformer 7 and programmable controller 8.The concrete connected mode of each device is as follows:
The input R of harmonic main frame 1 S T and three phase mains 10 A B C be connected, output U V W and intermediate frequency power supply 6 L1 L2 L3 be connected, harmonic main frame 1 and intermediate frequency power supply 6 form series relationship; The two ends of the first contactor 2 respectively with the input R of harmonic main frame 1 S T, output U V W be connected, the two forms parallel relationship; The output U1 of reactor 4 V1 W1 and capacitor 5 three binding post a b c be connected, input R1 S1 T1 be connected with the output of the second contactor 3, the input of the second contactor 3 again with the output tap CR of harmonic main frame 1 CS CT be connected, wherein, capacitor 5 inside adopts the wiring of triangle connected mode; The output of harmonic main frame 1 have U V W tri-lines, instrument transformer 7 is connected on V line; The input of programmable controller 8 is connected with instrument transformer 7, concrete, L and K of instrument transformer 7 is connected on I+ and I-of programmable controller 8, and the output switch of programmable controller 8 is connected on the control coil of the second contactor 3.
As the preferred scheme of one, reactor 4 is three-phase tuning reactor, and more preferably, the reactance Rate of this three-phase tuning reactor is 5-16%, is wherein that the result of use of the three-phase tuning reactor of 7% is best with reactance Rate.
As the preferred scheme of one, intermediate frequency power supply 6 is the intermediate frequency power supply of three-phase six impulse commutation.
In the present invention, first contactor 2 in parallel with harmonic main frame 1 can be switched to civil power operation in filter circuit fault or when safeguarding, thus makes intermediate frequency furnace can not affect normally carrying out of manufacturing schedule because filter circuit quits work; Instrument transformer 7 is for measuring electric current during filter circuit work, and electric current is inputed to programmable controller 8, the electric current that instrument transformer 7 measures by programmable controller 8 and setting electric current compare, determine whether the second contactor 3 starts, like this can according to the size of electric current, automatically, the control of intelligence be connected on harmonic main frame 1 output tap CR CS the work in LC filtering compensation loop on CT and the action of power factor compensation part, this LC filtering compensation loop is made up of filtering compensation reactor 4 and capacitor 5.Owing to being Current Control, when current value reaches set point, start LC filtering compensation circuit, both the problem that LC filtering compensation circuit works on when intermediate frequency furnace does not work had been avoided, also make power factor compensation capacitance can not occur with the change of external load to mend or few action switching of mending, decrease the phenomenon of capacitor 5 frequent switching.
In order to better monitor the effect of filter harmonic energy saving device, filter harmonic energy saving device of the present invention also comprises: electric power monitoring instrument 9.Electric power monitoring instrument 9 is installed on the input of harmonic main frame 1, its voltage sample line be connected on harmonic main frame 1 input R S on T, current sample line by access after instrument transformer (not shown) conversion, this instrument transformer be through three phase mains 10 output terminals A B on C.After access electric power monitoring instrument 9, can be real-time, effectively the operating state of filter harmonic energy saving device, electric power data tests and are shown, for operating personnel or equipment personnel observe and whether judgment device normally works, whether the electric power data of intermediate frequency furnace work normal.
As the preferred scheme of one, electric power monitoring instrument 9 has data transmission module, and it tests the data obtained can realize intelligent transportation, remote monitoring by data transmission module.
Intelligence filter harmonic energy saving device of the present invention has harmonic elimination concurrently, reduce surge and improve the effect of power factor, harmonic elimination after-current aberration rate drops to less than 10%, voltage distortion rate drops to less than 5%, voltage waveform and current waveform are corrected to sine wave, specifically see Fig. 2 (a) and (b) and Fig. 3 (a) and (b); Intelligence filter harmonic energy saving device of the present invention also has the features such as failure rate is low, reasonable price, capacity are large, and capacity can reach 175KW-6000KW; Meanwhile, because the capacitor of intelligence filter harmonic energy saving device absorbing except harmonic wave effect except having to compensate, also the power factor of system being compensated, thus making the power factor of system remain at more than 0.95.
It should be noted that, above-described embodiment does not limit the present invention in any form, the technical scheme that the mode that all employings are equal to replacement or equivalent transformation obtains, and all drops in protection scope of the present invention.
Claims (6)
1. be applicable to the intelligence filter harmonic energy saving device of intermediate frequency furnace, it is characterized in that, comprise: harmonic main frame (1), the first contactor (2), the second contactor (3), reactor (4), capacitor (5), intermediate frequency power supply (6), instrument transformer (7) and programmable controller (8), the input of above-mentioned harmonic main frame (1) is connected with three phase mains, output is connected with intermediate frequency power supply (6); Above-mentioned first contactor (2) is in parallel with harmonic main frame (1); The output of above-mentioned reactor (4) is connected with capacitor (5), input is connected with the second contactor (3), the input of the second contactor (3) is connected with the output tap of harmonic main frame (1) again, and above-mentioned capacitor (5) inside adopts the wiring of triangle connected mode; The output of harmonic main frame (1) have U V W tri-lines, above-mentioned instrument transformer (7) is connected on V line, instrument transformer (7) is for measuring electric current during filter circuit work, and electric current is inputed to programmable controller (8), the electric current that instrument transformer (7) measures by programmable controller (8) and setting electric current compare, and determine whether the second contactor (3) starts; The input of above-mentioned programmable controller (8) is connected with instrument transformer (7), and the normally opened contact of the second contactor (3) is connected with control coil; Also comprise: electric power monitoring instrument (9), the voltage sample line of above-mentioned electric power monitoring instrument (9) is connected on the input of harmonic main frame (1), and current sample line is by access after instrument transformer conversion, and above-mentioned instrument transformer is through on the output of three phase mains.
2. the intelligence filter harmonic energy saving device being applicable to intermediate frequency furnace according to claim 1, it is characterized in that, above-mentioned reactor (4) is three-phase tuning reactor.
3. the intelligence filter harmonic energy saving device being applicable to intermediate frequency furnace according to claim 2, it is characterized in that, the reactance Rate of above-mentioned three-phase tuning reactor is 5-16%.
4. the intelligence filter harmonic energy saving device being applicable to intermediate frequency furnace according to claim 3, it is characterized in that, the reactance Rate of above-mentioned three-phase tuning reactor is 7%.
5. the intelligence filter harmonic energy saving device being applicable to intermediate frequency furnace according to claim 1, is characterized in that, the intermediate frequency power supply that above-mentioned intermediate frequency power supply (6) is three-phase six impulse commutation.
6. the intelligence filter harmonic energy saving device being applicable to intermediate frequency furnace according to claim 1, it is characterized in that, above-mentioned electric power monitoring instrument (9) has data transmission module.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201210553934.9A CN102969719B (en) | 2012-12-19 | 2012-12-19 | Be applicable to the intelligence filter harmonic energy saving device of intermediate frequency furnace |
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| CN201210553934.9A CN102969719B (en) | 2012-12-19 | 2012-12-19 | Be applicable to the intelligence filter harmonic energy saving device of intermediate frequency furnace |
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| CN102969719A CN102969719A (en) | 2013-03-13 |
| CN102969719B true CN102969719B (en) | 2015-08-12 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106385032A (en) * | 2016-10-12 | 2017-02-08 | 中冶华天南京电气工程技术有限公司 | Harmonic management device for intermediate frequency furnace |
| CN106385033B (en) * | 2016-11-04 | 2019-01-25 | 中冶华天南京电气工程技术有限公司 | A kind of harmonic method and device of intermediate frequency furnace |
| CN110581666B (en) * | 2019-10-30 | 2021-10-01 | 渤海大学 | Six-pulse-wave low-quality-factor series resonance type medium-frequency induction heating inversion control method |
Citations (4)
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|---|---|---|---|---|
| CN201860109U (en) * | 2010-11-01 | 2011-06-08 | 东营市胜软石油技术开发有限公司 | Filtering compensation energy-saving device of oil drilling generator set |
| CN202034787U (en) * | 2011-04-25 | 2011-11-09 | 童淮安 | Anti-explosive filter compensation energy-saving set device for mines |
| CN202333812U (en) * | 2011-10-28 | 2012-07-11 | 保定华源电气新技术开发有限公司 | Quick switching reactive power filtration and compensation device |
| CN202978272U (en) * | 2012-12-19 | 2013-06-05 | 昆山协稳环保节能有限公司 | Intelligent harmonic wave filtering energy saving device suitable for intermediate frequency furnaces |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US7999418B2 (en) * | 2008-12-22 | 2011-08-16 | General Electric Company | Electrical system and control method |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201860109U (en) * | 2010-11-01 | 2011-06-08 | 东营市胜软石油技术开发有限公司 | Filtering compensation energy-saving device of oil drilling generator set |
| CN202034787U (en) * | 2011-04-25 | 2011-11-09 | 童淮安 | Anti-explosive filter compensation energy-saving set device for mines |
| CN202333812U (en) * | 2011-10-28 | 2012-07-11 | 保定华源电气新技术开发有限公司 | Quick switching reactive power filtration and compensation device |
| CN202978272U (en) * | 2012-12-19 | 2013-06-05 | 昆山协稳环保节能有限公司 | Intelligent harmonic wave filtering energy saving device suitable for intermediate frequency furnaces |
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Inventor after: Liu Hongjun Inventor after: Shen Qianqi Inventor before: Liu Hongjun Inventor before: Peng Zhenquan |
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Effective date of registration: 20160602 Address after: 201199 No. 89 East Friendship Road, Xhenzhuang Town, Shanghai, Minhang District Patentee after: JUNHUI ELECTRIC (CHINA) CO.,LTD. Address before: 215300 South Road, Lane three, Kunshan Development Zone, Jiangsu, Suzhou Patentee before: KUNSHAN XIEWIN ECONOMY SAVER Co.,Ltd. |
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