CN104064343A - Current mutual inductance device and current transformer - Google Patents
Current mutual inductance device and current transformer Download PDFInfo
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- CN104064343A CN104064343A CN201410313302.4A CN201410313302A CN104064343A CN 104064343 A CN104064343 A CN 104064343A CN 201410313302 A CN201410313302 A CN 201410313302A CN 104064343 A CN104064343 A CN 104064343A
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Abstract
The invention discloses a current mutual inductance device and a current transformer. The current mutual inductance device comprises an iron core, a primary winding and a secondary winding, wherein the primary winding and the secondary winding are arranged on the iron core. The secondary winding comprises a first output terminal, a second output terminal and a third output terminal, wherein the a first output resistor is connected between the first output terminal and the second output terminal, a second output resistor is connected between the first output terminal and the third output terminal, and the resistance value of the first output resistor is different from the resistance value of the second output resistor. The first output terminal and the second output terminal form a first output end. The first output terminal and the third output terminal form a second output end. By means of the current mutual inductance device and the current transformer, the problem that since a current transformer in the prior art is in a single-output pattern, the current transformer needs to be replaced when an output current needs to be converted is solved, dual output of the current transformer is achieved, and the current transformer does not need to be replaced when the output current changes (for example, from 1 A to 5 A).
Description
Technical field
The present invention relates to appliance field, in particular to a kind of current mutual-inductance apparatus summation current transformer.
Background technology
Precision current transformer is the high accuracy transmitter being applied in the intelligent arithmetic facilities such as electric power system secondary measurement, monitoring, protection; alternating current amount can be transformed into the voltage of corresponding amplitude phase place, thereby can supply the sampled data of computing for smart machine provides.
For electric power system secondary intelligent protection equipment, in the time breaking down in electric power system primary circuit, need intelligent protection equipment can make accurate judgement and accomplish not malfunction and not tripping, but of the prior artly can only protect the frequent misoperation of equipment, in order to tackle the impact of electric power system primary circuit short trouble to secondary monitoring and protecting equipment, secondary instrument transformer has corresponding limit value to the electric current progress of disease to the current amplitude of secondary, this just causes because type selecting is improper or system short-circuit fault is estimated deficiency, in the time of system short-circuit, cause the saturated of secondary current instrument transformer because electric current is excessive, thereby make secondary instrument transformer lose the ability of reflection primary current state.The precision transformer of for this reason selecting in current secondary intellectual monitoring, protection equipment all adopts the iron core with magnetic gap, to resist the intelligent protection equipment tripping problem causing because instrument transformer is saturated.The precision current transformer of employing with air-gap iron core technology; can effectively solve the problem that secondary is saturated; prevent the tripping of intelligent protection equipment; but the ruuning situation of the national intelligent protection equipment providing according to national grid research institute statistics; the whole nation has 4% intelligent protection equipment still to have differential protection malfunction problem; the failure wave-recording of all kinds of maloperations is carried out to waveform analysis known; with the current transformer of air gap; exist secondary progress of disease wave mode to fall the wave distortion phenomenon of sticking up tail with terminal, this phenomenon can cause the malfunction of intelligent protection equipment.
In addition, current intelligent protection equipment, for being divided into two shelves for the specified limit value of secondary current instrument transformer, is respectively 1A and 5A, according to power system capacity and may be on the impact of secondary, selects different secondary rated values.Existing precision transformer is all single output mode, this just needs equipment manufacturer to prepare the hardware plug of two kinds of specifications, inventory cost is relatively high, in the time occurring that supply of material equipment is different from field demand, be also rated at 1A, 5A when conversion smart machine at secondary system and need to change that instrument transformer is changed plug-in unit and manpower, time loss is all very large.
There is following defect in the precision transformer that to sum up, existing smart machine adopts:
1, iron core band air gap, because iron core exists air gap, the remanent magnetism of iron core reduces greatly, although solved preferably transient state saturation problem, but owing to there is leakage field, in transient process, there will be drop type decay and terminal to stick up the distortion situations such as tail, may cause the incorrect operation of intelligent protection equipment;
2, because the specified output valve of secondary current in power system is divided into two types of 1A, 5A, existing precision transformer is all single output mode, and in the time that secondary system is rated at 1A, 5A conversion, smart machine need to be changed instrument transformer, and manpower, time loss are all very large.
Be single output mode for current transformer in prior art, in the time that output current changes, need to change the problem of current transformer, not yet propose at present effective solution.
Summary of the invention
Be single output mode for current transformer in correlation technique, in the time that output current changes, need to change the problem of current transformer, not yet propose at present effective solution, for this reason, main purpose of the present invention is to provide a kind of current mutual-inductance apparatus summation current transformer, to address the above problem.
To achieve these goals, according to an aspect of the present invention, provide a kind of current mutual-inductance apparatus, this current mutual-inductance apparatus comprises: iron core; Armature winding, is arranged on iron core; Secondary winding, be arranged on iron core, secondary winding comprises the first lead-out terminal, the second lead-out terminal and the 3rd lead-out terminal, wherein, between the first lead-out terminal and the second lead-out terminal, be connected with the first output resistance, between the first lead-out terminal and the 3rd lead-out terminal, be connected with the second output resistance, wherein, the first output resistance is different from the resistance of the second output resistance; The first lead-out terminal and the second lead-out terminal form the first output, and the first lead-out terminal and the 3rd lead-out terminal form the first output.
Further, armature winding is through the centre bore of the coil of iron core; Secondary winding is evenly wound on iron core.
Further, secondary winding is evenly wound on iron core by loop wire winder.
Further, on the outer surface of secondary winding, be surrounded by two layers polyester thin dielectric film.
Further, the first output resistance comprises: the first resistance, and the first end of the first resistance is connected with the first lead-out terminal, and the second end of the first resistance is connected with the second lead-out terminal; The second output resistance comprises: the first resistance and the second resistance, and the first end of the second resistance is connected with the second end of the first resistance, and the second end of the second resistance is connected with the second end of the first resistance.
Further, iron core is without air gap annular silicon steel iron core.
Further, the iron core that is provided with armature winding and secondary winding is placed in shell, shell epoxy encapsulation.
Further, between armature winding and secondary winding, be provided with screen.
To achieve these goals, according to an aspect of the present invention, provide a kind of current transformer, this current transformer comprises: current mutual-inductance apparatus.
Pass through the above embodiment of the present invention, the secondary winding being arranged on iron core has three lead-out terminals, form two outputs by three lead-out terminals, realize the dual output of current mutual-inductance apparatus, making this current mutual-inductance apparatus can be used as 1A instrument transformer uses, also can be used as 5A instrument transformer uses, having solved current transformer in prior art is single output mode, in the time that need to changing, output current need to change the problem of current transformer, realize the dual output of current transformer, in the time that output current changes, (as 1A is converted to 5A) is without changing current transformer, reduce the kind of instrument transformer in smart machine, and this current mutual-inductance apparatus is simple in structure, cost is low, convenient installation, result of use is good.
Brief description of the drawings
Accompanying drawing described herein is used to provide a further understanding of the present invention, forms the application's a part, and schematic description and description of the present invention is used for explaining the present invention, does not form inappropriate limitation of the present invention.In the accompanying drawings:
Fig. 1 is according to the schematic diagram of the current mutual-inductance apparatus of the embodiment of the present invention; And
Fig. 2 is according to the structure chart of the current mutual-inductance apparatus of the embodiment of the present invention.
Embodiment
First the part noun or the term that, in the process that the embodiment of the present invention is described, occur are applicable to description below:
Capacity Margin coefficient: as long as in low load condition, having in sufficient " Capacity Margin coefficient " situation, is not to have better transient performance with the P level current transformer of air gap, ring-shaped core.Its Capacity Margin coefficient just can meet the undersaturated requirement of transient state when above substantially 30.Want to reach Capacity Margin coefficient more than 30, instrument transformer secondary rated current should adopt 1A, so for transient protection and instrument transformer used, 30 above secondary rated current have only had the standard of 1A, there is no the specification of 5A.Even in actual application, transient protection secondary rated current adopts 0.5A, and its instrument transformer " Capacity Margin coefficient " can reach more than 60.
In the time that Capacity Margin coefficient 30 is above, likely in double above short circuit, still correct progress of disease transient current of current transformer; If when Capacity Margin coefficient 60 is above, likely in continuous more than five times short circuit, still correct progress of disease transient current of current transformer.Thereby can ensure the correct operation of the protections such as quick-break, time delay quick-break and overcurrent completely, and main protection can misoperation in the time of external area error weight and lock.
Transient protection: China proposes Current Transformer for Transient Protection transient characterisitics technical requirement in GB-16847-1997 with reference to IEC44-6:1992 standard; in regulation, transient protection should adopt the instrument transformer with air gap TPY level with transient performance, has but ignored in Appendix D 1 and explicitly point out " ability that this does not get rid of P level current transformer and have transient performance ".
As long as in low load condition, have in sufficient " Capacity Margin coefficient " situation, not to there is better transient performance with the P level current transformer of air gap, ring-shaped core.Its Capacity Margin coefficient just can meet the undersaturated requirement of transient state when above substantially 30.Want to reach Capacity Margin coefficient more than 30, instrument transformer secondary rated current should adopt 1A, so for transient protection and instrument transformer used, 30 above secondary rated current have only had the standard of 1A, there is no the specification of 5A.Even in actual application, transient protection secondary rated current adopts 0.5A, and its instrument transformer " Capacity Margin coefficient " can reach more than 60.
In the time that Capacity Margin coefficient 30 is above, likely in double above short circuit, still correct progress of disease transient current of current transformer; If when Capacity Margin coefficient 60 is above, likely in continuous more than five times short circuit, still correct progress of disease transient current of current transformer.Thereby can ensure the correct operation of the protections such as quick-break, time delay quick-break and overcurrent completely, and main protection can misoperation in the time of external area error weight and lock.
In order to make those skilled in the art person understand better the present invention program, below in conjunction with the accompanying drawing in the embodiment of the present invention, technical scheme in the embodiment of the present invention is clearly and completely described, obviously, described embodiment is only the embodiment of a part of the present invention, instead of whole embodiment.Based on the embodiment in the present invention, those of ordinary skill in the art, not making the every other embodiment obtaining under creative work prerequisite, should belong to the scope of protection of the invention.
It should be noted that, term " first ", " second " etc. in specification of the present invention and claims and above-mentioned accompanying drawing are for distinguishing similar object, and needn't be used for describing specific order or precedence.The data that should be appreciated that such use suitably can exchanged in situation, so as embodiments of the invention described herein can with except diagram here or describe those order enforcement.In addition, term " comprises " and " having " and their any distortion, intention is to cover not exclusive comprising, for example, those steps or unit that process, method, system, product or the equipment that has comprised series of steps or unit is not necessarily limited to clearly list, but can comprise clearly do not list or for these processes, method, product or equipment intrinsic other step or unit.
To achieve these goals, according to an aspect of the present invention, provide a kind of current mutual-inductance apparatus, this current mutual-inductance apparatus can comprise: iron core; Armature winding, is arranged on iron core; Secondary winding, be arranged on iron core, secondary winding comprises the first lead-out terminal, the second lead-out terminal and the 3rd lead-out terminal, wherein, between the first lead-out terminal and the second lead-out terminal, be connected with the first output resistance, between the first lead-out terminal and the 3rd lead-out terminal, be connected with the second output resistance, wherein, the first output resistance is different from the resistance of the second output resistance; The first lead-out terminal and the second lead-out terminal form the first output, and the first lead-out terminal and the 3rd lead-out terminal form the first output.
Pass through the above embodiment of the present invention, the secondary winding being arranged on iron core has three lead-out terminals, form two outputs by three lead-out terminals, realize the dual output of current mutual-inductance apparatus, making this current mutual-inductance apparatus can be used as 1A instrument transformer uses, also can be used as 5A instrument transformer uses, having solved current transformer in prior art is single output mode, in the time that need to changing, output current need to change the problem of current transformer, realize the dual output of current transformer, in the time that output current changes, (as 1A is converted to 5A) is without changing current transformer, reduce the kind of instrument transformer in smart machine, and this current mutual-inductance apparatus is simple in structure, cost is low, convenient installation, result of use is good.
By the above embodiment of the present invention, two kinds of specification products of 1A and 5A can share an instrument transformer, can simplify the process of two kinds of mode conversions, meet user's all kinds of demands.
In the above embodiment of the present invention, armature winding is through the centre bore of the coil of iron core; Secondary winding is evenly wound on iron core.
Wherein, current mutual-inductance apparatus can comprise iron core, armature winding and secondary winding, and iron core wherein adopts high annular silicon steel iron core of leading, and secondary winding is evenly wound on iron core, and armature winding is a circle only, directly through Combined iron core centre bore.
Particularly, secondary winding is evenly wound on iron core by loop wire winder.
Need to be on the outer surface of secondary winding, to be surrounded by two layers polyester thin dielectric film with further illustrating.
According to the abovementioned embodiments of the present invention, the first output resistance can comprise: the first resistance, and the first end of the first resistance is connected with the first lead-out terminal, and the second end of the first resistance is connected with the second lead-out terminal; The second output resistance comprises: the first resistance and the second resistance, and the first end of the second resistance is connected with the second end of the first resistance, and the second end of the second resistance is connected with the second end of the first resistance.
In the above embodiment of the present invention, iron core is without air gap annular silicon steel iron core.Adopt the high structure of leading without air gap annular silicon steel iron core, effectively amplitude and the phase place of the electric weight of the first winding of the progress of disease.
Particularly, the iron core that is provided with armature winding and secondary winding is placed in shell, shell epoxy encapsulation.
Further, between armature winding and secondary winding, be provided with screen.
In the schematic diagram shown in Fig. 1, two resistance of configuration in the output of current mutual-inductance apparatus, between two resistance, draw a binding post 5 (being the second lead-out terminal in above-described embodiment), when binding post 4 and 5 (binding post 4 is wherein the 3rd lead-out terminal) is not when short circuit, the first lead-out terminal (being the binding post 6 shown in Fig. 1) and the 3rd lead-out terminal form the first output, are applicable to the input of 1A; In the time of terminal 4,5 short circuit, be applicable to the input of 5A, realize the input pattern of two kinds of specifications.Unify the instrument transformer board package of Microcomputer Protection equipment, in the time that 5A uses the input of 1A instead, can no longer need to change instrument transformer or change instrument transformer board package, needn't change instrument transformer or instrument transformer plate, can not cause scrapping and polluting of components and parts.
As depicted in figs. 1 and 2, current mutual-inductance apparatus comprises iron core 1, armature winding 3 and secondary winding 2, the first output resistance R1 and the second output resistance R2; Can with loop wire winder by even secondary winding 2 coiling to group iron core 1, the outer surface polyester film insulating barrier of double-baging, armature winding 3, directly through iron-core coil centre bore, adopts close circle lap wound and the shield technology that winds the line, and effectively expands capacity redundancy; In the output of current mutual-inductance apparatus, configure two resistance R 1, R2, between two resistance, draw a binding post 5, when binding post 4,5 is not the output of 1A when short circuit; In the time of binding post 4,5 short circuit, be the output of 5A, realize the output mode of two kinds of specifications.
Alternatively, the iron core 1 that is wound with winding is put into plastic shell epoxy encapsulation, wherein secondary winding 2 is by going between or drawing pin and draw shell, and armature winding 3 is drawn shell by lead-in wire.
When use, armature winding 3 is concatenated in test line, 4,5 pins are elementary input 20A when short circuit not, secondary output 0.80V; By the elementary input 100A of 4,5 pin short circuit, secondary output 0.80V,
R1 in above-described embodiment is connected between binding post 5,6, and resistance value can be 20 Ω; R2 is connected between binding post 4,5, and resistance value can be 80 Ω.Armature winding is 1 circle, and secondary winding is 2500 circles.
Alternatively, as shown in Figure 1, between armature winding and secondary winding, be provided with screen 8, this shielding layer grounding.
To achieve these goals, according to an aspect of the present invention, provide a kind of current transformer, this current transformer comprises: current mutual-inductance apparatus.
Pass through the above embodiment of the present invention, the secondary winding being arranged on iron core has three lead-out terminals, form two outputs by three lead-out terminals, realize the dual output of current mutual-inductance apparatus, making this current mutual-inductance apparatus can be used as 1A instrument transformer uses, also can be used as 5A instrument transformer uses, having solved current transformer in prior art is single output mode, in the time that need to changing, output current need to change the problem of current transformer, realize the dual output of current transformer, in the time that output current changes, (as 1A is converted to 5A) is without changing current transformer, reduce the kind of instrument transformer in smart machine, and this current mutual-inductance apparatus is simple in structure, cost is low, convenient installation, result of use is good.
As can be seen from the above description, the present invention has realized following technique effect:
Pass through the above embodiment of the present invention, the secondary winding being arranged on iron core has three lead-out terminals, form two outputs by three lead-out terminals, realize the dual output of current mutual-inductance apparatus, making this current mutual-inductance apparatus can be used as 1A instrument transformer uses, also can be used as 5A instrument transformer uses, having solved current transformer in prior art is single output mode, in the time that need to changing, output current need to change the problem of current transformer, realize the dual output of current transformer, in the time that output current changes, (as 1A is converted to 5A) is without changing current transformer, reduce the kind of instrument transformer in smart machine, and this current mutual-inductance apparatus is simple in structure, cost is low, convenient installation, result of use is good.
The foregoing is only the preferred embodiments of the present invention, be not limited to the present invention, for a person skilled in the art, the present invention can have various modifications and variations.Within the spirit and principles in the present invention all, any amendment of doing, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.
Claims (9)
1. a current mutual-inductance apparatus, is characterized in that, comprising:
Iron core;
Armature winding, is arranged on described iron core;
Secondary winding, be arranged on described iron core, described secondary winding comprises the first lead-out terminal, the second lead-out terminal and the 3rd lead-out terminal, wherein, between described the first lead-out terminal and described the second lead-out terminal, be connected with the first output resistance, between described the first lead-out terminal and described the 3rd lead-out terminal, be connected with the second output resistance
Wherein, described the first output resistance is different from the resistance of described the second output resistance; Described the first lead-out terminal and described the second lead-out terminal form the first output, and described the first lead-out terminal and described the 3rd lead-out terminal form the first output.
2. current mutual-inductance apparatus according to claim 1, is characterized in that,
Described armature winding is through the centre bore of the coil of described iron core;
Described secondary winding is evenly wound on described iron core.
3. current mutual-inductance apparatus according to claim 2, is characterized in that, described secondary winding is evenly wound on described iron core by loop wire winder.
4. according to the current mutual-inductance apparatus described in any one in claims 1 to 3, it is characterized in that, on the outer surface of described secondary winding, be surrounded by two layers polyester thin dielectric film.
5. current mutual-inductance apparatus according to claim 1, is characterized in that,
Described the first output resistance comprises: the first resistance, and the first end of described the first resistance is connected with described the first lead-out terminal, and the second end of described the first resistance is connected with described the second lead-out terminal;
Described the second output resistance comprises: described the first resistance and the second resistance, and the first end of described the second resistance is connected with the second end of described the first resistance, and the second end of described the second resistance is connected with the second end of described the first resistance.
6. current mutual-inductance apparatus according to claim 1, is characterized in that, described iron core is without air gap annular silicon steel iron core.
7. according to the current mutual-inductance apparatus described in claim 1 or 2 or 3 or 5 or 6, it is characterized in that, the described iron core that is provided with described armature winding and described secondary winding is placed in shell, described shell epoxy encapsulation.
8. according to the current mutual-inductance apparatus described in claim 1 or 2 or 3 or 5 or 6, it is characterized in that, between described armature winding and described secondary winding, be provided with screen.
9. a current transformer, is characterized in that, comprises the current mutual-inductance apparatus described in any one in claim 1 to 8.
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108878105A (en) * | 2017-05-08 | 2018-11-23 | 台达电子工业股份有限公司 | transformer |
US11250987B2 (en) | 2017-05-08 | 2022-02-15 | Delta Electronics, Inc. | Transformer |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6028422A (en) * | 1997-02-17 | 2000-02-22 | Vacuumschmelze Gmbh | Current transformer |
CN101206951A (en) * | 2007-11-16 | 2008-06-25 | 介国安 | Energy-saving current transformer |
CN101692399A (en) * | 2009-09-30 | 2010-04-07 | 淄博元星电子有限公司 | Transient current transformer |
CN201859771U (en) * | 2010-11-15 | 2011-06-08 | 山东浩特电气有限公司 | High-multiplying-power composite transformation ratio current transformer |
CN102760562A (en) * | 2012-08-08 | 2012-10-31 | 江苏中容科技有限公司 | Three-dimensional rolling iron core dry type transformer insulation tube between high voltage and low voltage |
CN102930967A (en) * | 2012-10-30 | 2013-02-13 | 中国西电电气股份有限公司 | Bundled current transformer for GIS and manufacturing method of transformer |
CN103050264A (en) * | 2012-12-12 | 2013-04-17 | 北京航空航天大学 | Multiple-transformation-ratio selectable outdoor open-type current transformer |
-
2014
- 2014-07-02 CN CN201410313302.4A patent/CN104064343A/en active Pending
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6028422A (en) * | 1997-02-17 | 2000-02-22 | Vacuumschmelze Gmbh | Current transformer |
CN101206951A (en) * | 2007-11-16 | 2008-06-25 | 介国安 | Energy-saving current transformer |
CN101692399A (en) * | 2009-09-30 | 2010-04-07 | 淄博元星电子有限公司 | Transient current transformer |
CN201859771U (en) * | 2010-11-15 | 2011-06-08 | 山东浩特电气有限公司 | High-multiplying-power composite transformation ratio current transformer |
CN102760562A (en) * | 2012-08-08 | 2012-10-31 | 江苏中容科技有限公司 | Three-dimensional rolling iron core dry type transformer insulation tube between high voltage and low voltage |
CN102930967A (en) * | 2012-10-30 | 2013-02-13 | 中国西电电气股份有限公司 | Bundled current transformer for GIS and manufacturing method of transformer |
CN103050264A (en) * | 2012-12-12 | 2013-04-17 | 北京航空航天大学 | Multiple-transformation-ratio selectable outdoor open-type current transformer |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108878105A (en) * | 2017-05-08 | 2018-11-23 | 台达电子工业股份有限公司 | transformer |
US11037723B2 (en) | 2017-05-08 | 2021-06-15 | Delta Electronics, Inc. | Transformer |
US11250987B2 (en) | 2017-05-08 | 2022-02-15 | Delta Electronics, Inc. | Transformer |
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Application publication date: 20140924 |