CN102436897A - Flexible Rogowski coil used for detecting direct-current system short-circuit current and method for designing same - Google Patents
Flexible Rogowski coil used for detecting direct-current system short-circuit current and method for designing same Download PDFInfo
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- CN102436897A CN102436897A CN2011102731440A CN201110273144A CN102436897A CN 102436897 A CN102436897 A CN 102436897A CN 2011102731440 A CN2011102731440 A CN 2011102731440A CN 201110273144 A CN201110273144 A CN 201110273144A CN 102436897 A CN102436897 A CN 102436897A
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Abstract
The invention discloses a flexible Rogowski coil used for detecting the direct-current system short-circuit current and a method for designing the same, the coil comprises a coil and a loop uniformly wound around an annular flexible framework with an opening, an outer layer insulating bush is sleeved outside the coil and the loop, a plug-type interface attached to the coil and the loop is installed on the opening of the annular flexible framework, the coil outgoing line is connected with a sampling resistance module after being educed through the hole of the plug-type interface, the sampling resistance module educes a signal and is connected with a post-integrating circuit. In the Rogowski coil loop winding technique adopted in the invention, the return wire and the coil winding are constituted by one wire. The head end and the tip end of the Rogowski coil are connected by the plug-type interface, which can improve the mechanical life of the Rogowski coil to a great extent, has the advantages of high reliability and convenience for disassembly and installation; the method for designing the Rogowski coil used for detecting the direct-current system short-circuit current can combine the short circuit physical circumstances and the field working condition of the direct-current system.
Description
Technical field
The invention belongs to electronic current mutual inductor, be specifically related to a kind of Luo-coil and method for designing thereof that is used for the direct current system short circuit current measurement.
Background technology
In order to detect fault fast when the direct current power system failed because,, be widely used based on the Luo-coil of electromagnetic induction principle simultaneously in order to be connected with the digital intelligent unit more easily realizing digitized measurement and protection.
Compare with other transient current detection method; The skeleton that the open-core type Luo-coil is adopted is the nonferromagnetic insulating material, because it does not contain iron core, does not have the magnetic saturation problem in theory; Receive the restriction of tested size of current hardly, be very suitable for measurement big electric current.
In being directed against the measurement of the big electric current of transient state; Measurement in the past based on Luo-coil, technologic performance still remains to improve open-core type Luo-coil in the past on the one hand; Since the coiling the enamelled wire that adopts thinner; Do the time spent when Luo-coil receives external force, enamelled wire is broken easily, causes the fault of Luo-coil product; On the other hand, the method for designing that lacks a kind of procedure is as guidance, better to be connected with the digital intelligent unit to realize digitized measurement and protection.
Summary of the invention
The object of the present invention is to provide and a kind ofly can convert the amplitude transient current signal to can be connected high-precision and be used for flexible Luo-coil and the method for designing thereof that the direct current system short circuit current detects with the digitalized intelligent cell in back.
For achieving the above object; Flexible Luo-coil of the present invention comprises coil and the loop line that evenly is wound on the annular flexible back bone that has opening; Outside coil and loop line, be set with the outer layer insulation sleeve pipe; The plug-in type interface that is connected with coil and loop line is installed on the opening of annular flexible back bone, and the coil outlet links to each other with the sample resistance module after draw in the hole of plug-in type interface, and the sample resistance module is drawn signal and is connected with back level integrating circuit.
Described sample resistance module comprises the sample resistance that is connected with the coil outlet through the plug-in type interface, and the two ends while of said sample resistance is connected with the BNC socket on the protecting sheathing.
Described flexible back bone is made up of flexible insulating material, and how much mid portions of this flexible back bone offer the through hole that loop line is passed through.
Described coil and loop line penetrate the through hole of flexible back bone from an end of flexible back bone; Draw the back by the other end and be wound on the flexible back bone uniformly, and on the loop line that passes the flexible back bone through hole, be set with fastening and Teflom Insulation Material protective effect with the individual layer mode.
The two ends of described plug-in type interface are matrix, are provided with thread groove in the middle of the plug-in type interface and are threaded with the sample resistance module.
Method for designing of the present invention is following:
1) earlier according to the spectrum analysis that direct current system is the short circuit current of index variation, confirms the lower-frequency limit of Luo-coil, confirm outer integration circuit time constant according to the lower-frequency limit of gained;
2) then according to the size of current carrying bus, under guaranteeing the condition that the insulation condition satisfies, confirm the Luo-coil flexible back bone size and according to tested current peak with outside integration circuit time constant confirm the mutual inductance of Luo-coil;
3) judge at first whether single layer coil and loop line satisfy the requirement of Luo-coil mutual inductance size,, then change the flexible back bone diameter of section and make single layer coil and loop line satisfy the requirement of mutual inductance size if can not satisfy;
4) if satisfy the requirement of Luo-coil mutual inductance then make the go forward side by side measurement of line parameter of Luo-coil, confirm the size of outer meeting resistance according to optimum Match.
Flexible hollow formula Luo-coil involved in the present invention improves the structural manufacturing process of Luo-coil, under the prerequisite that guarantees certainty of measurement, and the mechanical endurance of having improved Luo-coil.Simultaneously, propose a kind of general method for designing, be used for the detection of electric current under the direct current power system short circuit condition.
The flexible Luo-coil that is used for the detection of direct current system short circuit current proposed by the invention, framework material should be chosen temperature characterisitic material preferably, adopts the framework material of silicon rubber as Luo-coil.That silicon rubber has is high temperature resistant, high pressure resistant, waterproof, performance such as anticorrosion, can be operated in-60 ℃～+ 180 ℃, has good pliability, is the ideal material of flexible Luo-coil skeleton.
In the past about the loop line of flexible Luo-coil; Mostly be to utilize the heart yearn of cable own as the Luo-coil loop line; Though install simply, need heart yearn and enamelled wire be welded, the shortcoming that this technology is brought is exactly the electric capacity of distribution certainly that will increase coil itself; Reduce the frequency bandwidth of coil itself, influence certainty of measurement.The Luo-coil loop line wire winding that the present invention adopted, loop line and coil-winding itself is made up of a line, specifically is that the silicone rubber for cable inner core is taken out, and polytetrafluoroethylmaterial material is inserted in cable inside, as the protective casing of enamelled wire.The skin that described Teflom Insulation Material is enclosed within enamelled wire plays fastening and the protective effect that prevents to rupture, and the loop construction that this technology is made is compact, and fastness is good, can guarantee very high certainty of measurement simultaneously, suitable commercial production use.
Described Luo-coil coiling is adopted evenly close around mode; This winding mode can guarantee that good interference free performance and very big degree have reduced the inhomogeneous institute of coiling errors caused; The close mutual inductance that can increase coil around mode has simultaneously improved the signal to noise ratio of measuring.
Description of drawings
Fig. 1 is the structural representation of Luo-coil sensing head;
Fig. 2 is the structural representation of Luo-coil sensing head sample resistance module;
Fig. 3 is the structure chart of the outer integrating circuit of Luo-coil;
Fig. 4 is the design flow diagram of outer integral form Luo-coil.
Embodiment
Explain further details below in conjunction with accompanying drawing.
Referring to Fig. 1, the present invention includes flexible back bone 2, coil and loop line 1, outer layer insulation sleeve pipe 3, sample resistance module 4 and plug-in type interface 5; Said coil evenly is wound on the flexible back bone 2, and the coil loop line is embedded in the geometric center of flexible back bone 2, and draw after sample resistance module 4 through plug-in type interface 5 at the coiling two ends; Whole Luo-coil constitutes the annulus of an opening, and first end connects through plug-in type interface 5 in use, and Luo-coil is drawn signal and is connected with back level integrating circuit.The Luo-coil loop line wire winding that the present invention adopted, loop line and coil-winding itself is made up of a line, specifically is that the silicone rubber for cable inner core is taken out, and polytetrafluoroethylmaterial material is inserted in cable inside, as the protective casing of enamelled wire.The skin that described Teflom Insulation Material is enclosed within enamelled wire plays fastening and the protective effect that prevents to rupture, and the loop construction that this technology is made is compact, and fastness is good, can guarantee very high certainty of measurement simultaneously, suitable commercial production use.
Referring to Fig. 2, the sample resistance 8 of lead-out wires of coil after draw in the hole of plug-in type interface 5 and in the sample resistance module 4 is welded to connect.The sample resistance two ends simultaneously with protecting sheathing 7 on BNC socket 6 be welded to connect.BNC socket is connected with Shielded Twisted Pair, adopts screen to weakening Electrostatic Coupling and electromagnetic coupled effect clearly to be arranged, and screen should guarantee good earth simultaneously.Twisted-pair feeder then reduces inductive interference through the induction area that reduces go-and-return line.
Referring to Fig. 3, external integrating circuit adopts active integration, comprises four parts: i.e. voltage follower circuit, outer integrating circuit, filter circuit, amplifying circuit.
Referring to Fig. 4, the design cycle of the Luo-coil of outer integral form of the present invention is following:
1), confirms the lower-frequency limit of Luo-coil according to energy distributions characteristic in the signal spectrum characteristic, to guarantee to reflect accurately the frequency characteristic of primary signal earlier according to the spectrum analysis that direct current system is the short circuit current of index variation.Because the lower-frequency limit of outer integration type Luo-coil is decided by outer integration circuit time constant, promptly
(f
lFor the lower-frequency limit τ of Luo-coil is outer integration circuit time constant), so can confirm outer integration circuit time constant according to the lower-frequency limit of gained;
2) then according to the size of current carrying bus; Guaranteeing under the condition that the insulation condition satisfies; Guarantee that promptly system voltage air under setpoint distance is not breakdown; Confirm the size of Luo-coil flexible back bone and confirm the mutual inductance of Luo-coil, promptly according to formula according to tested current peak and outer integration circuit time constant
(wherein M is the mutual inductance of Luo-coil, u
0Maximum for according to the definite measurement output voltage of system is generally 10V or 5V etc., and τ is outer integration circuit time constant, and I is the peak value of current measured);
3) judge at first whether coil and loop line individual layer winding mode satisfy the requirement of Luo-coil mutual inductance size, promptly judge hypothesis in the individual layer coiling and evenly closely under mode, whether can satisfy the mutual inductance requirement, this point can be according to the formula mutual inductance
(μ wherein
0Be the magnetic permeability of air, value is 4 π * 10
-7, N is the number of turns under the individual layer winding mode, D is the diameter of Luo-coil, d is the flexible back bone diameter of section) draw, if can not satisfy, then change the flexible back bone diameter of section and make single layer coil and loop line satisfy the requirement of mutual inductance size;
4) if satisfy the requirement of Luo-coil mutual inductance then make the Luo-coil line parameter self-induction of loop L that goes forward side by side
c, stary capacity of coil C
cAnd coil internal resistance R
cMeasurement, according to optimum Match, promptly
Confirm outer meeting resistance R
sSize.
Claims (6)
1. one kind is used for the flexible Luo-coil that the direct current system short circuit current detects; It is characterized in that: comprise the coil and the loop line (1) that evenly are wound on the annular flexible back bone (2) that has opening; Outside coil and loop line (1), be set with outer layer insulation sleeve pipe (3); The plug-in type interface (5) that is connected with coil and loop line (1) is installed on the opening of annular flexible back bone (2); The coil outlet links to each other with sample resistance module (4) after draw in the hole of plug-in type interface (5), and sample resistance module (4) is drawn signal and is connected with back level integrating circuit.
2. the flexible Luo-coil that is used for the detection of direct current system short circuit current according to claim 1; It is characterized in that: described sample resistance module (4) comprises the sample resistance (8) that is connected with the coil outlet through plug-in type interface (5), and the two ends while of said sample resistance (8) is connected with the BNC socket (6) on the protecting sheathing (7).
3. the flexible Luo-coil that is used for the detection of direct current system short circuit current according to claim 1; It is characterized in that: described flexible back bone (2) is made up of flexible insulating material, and how much mid portions of this flexible back bone (2) offer the through hole that loop line is passed through.
4. the flexible Luo-coil that is used for the detection of direct current system short circuit current according to claim 1; It is characterized in that: described coil and loop line (1) penetrate the through hole of flexible back bone (2) from an end of flexible back bone (2); Draw the back by the other end and be wound on uniformly on the flexible back bone (2), and on the loop line that passes the flexible back bone through hole, be set with fastening and Teflom Insulation Material protective effect with the individual layer mode.
5. the flexible Luo-coil that is used for the detection of direct current system short circuit current according to claim 1; It is characterized in that: the two ends of described plug-in type interface (5) are matrix, are provided with thread groove in the middle of the plug-in type interface (5) and are threaded with sample resistance module (4).
6. method for designing that is used for the flexible Luo-coil that the direct current system short circuit current detects is characterized in that:
1) earlier according to the spectrum analysis that direct current system is the short circuit current of index variation, confirms the lower-frequency limit of Luo-coil, confirm outer integration circuit time constant according to the lower-frequency limit of gained;
2) then according to the size of current carrying bus, under guaranteeing the condition that the insulation condition satisfies, confirm the Luo-coil flexible back bone size and according to tested current peak with outside integration circuit time constant confirm the mutual inductance of Luo-coil;
3) judge at first whether single layer coil and loop line satisfy the requirement of Luo-coil mutual inductance size,, then change the flexible back bone diameter of section and make single layer coil and loop line satisfy the requirement of mutual inductance size if can not satisfy;
4) if satisfy the requirement of Luo-coil mutual inductance then make the go forward side by side measurement of line parameter of Luo-coil, confirm the size of outer meeting resistance according to optimum Match.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110273144.0A CN102436897B (en) | 2011-09-15 | 2011-09-15 | Flexible Rogowski coil used for detecting direct-current system short-circuit current and method for designing same |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110273144.0A CN102436897B (en) | 2011-09-15 | 2011-09-15 | Flexible Rogowski coil used for detecting direct-current system short-circuit current and method for designing same |
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| CN102436897A true CN102436897A (en) | 2012-05-02 |
| CN102436897B CN102436897B (en) | 2014-01-29 |
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Cited By (16)
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|---|---|---|---|---|
| CN102751081A (en) * | 2012-07-03 | 2012-10-24 | 深圳市创银科技股份有限公司 | Flexible coil current transformer and production method thereof |
| CN103235169A (en) * | 2013-04-25 | 2013-08-07 | 国家电网公司 | Measuring device for pre-discharging current before insulation breakthrough at VFTO (very fast transient overvoltage) |
| CN103777055A (en) * | 2013-12-03 | 2014-05-07 | 国家电网公司 | Multiple Rogowski coil parallel-connected outer integration sensor |
| CN103852627A (en) * | 2012-11-30 | 2014-06-11 | 海洋王（东莞）照明科技有限公司 | Alternating-current circuit current probing device |
| CN103852626A (en) * | 2012-11-30 | 2014-06-11 | 海洋王（东莞）照明科技有限公司 | Direct current circuit detection device |
| CN104076190A (en) * | 2013-03-29 | 2014-10-01 | 海洋王（东莞）照明科技有限公司 | Direct current detection circuit |
| CN104297558A (en) * | 2014-10-08 | 2015-01-21 | 中国科学院电工研究所 | Current measuring device |
| CN104345196A (en) * | 2014-10-30 | 2015-02-11 | 南京信息工程大学 | Active weak power frequency current induction coil |
| CN105448498A (en) * | 2015-12-07 | 2016-03-30 | 深圳供电局有限公司 | Traveling wave sensor and coil winding method for magnetic core for traveling wave sensor |
| CN106526279A (en) * | 2015-09-10 | 2017-03-22 | 赛米控电子股份有限公司 | Centering retaining device for Rogowski coil and method for arranging Rogowski coil |
| CN106526302A (en) * | 2016-10-25 | 2017-03-22 | 华中科技大学 | Method for manufacturing high-performance air-core coil with balanced turns |
| CN107768904A (en) * | 2017-10-26 | 2018-03-06 | 国网宁夏电力公司检修公司 | Plug-in Rogowski coil device |
| CN108594312A (en) * | 2018-07-30 | 2018-09-28 | 吉林省电力科学研究院有限公司 | A kind of the grounded screen breakpoint detection device and method of arch form solenoid transmission coil |
| CN109613316A (en) * | 2018-11-29 | 2019-04-12 | 江阴市星火电子科技有限公司 | A kind of high-precision rogowski coil |
| CN112730944A (en) * | 2020-12-19 | 2021-04-30 | 华中科技大学 | Current measuring method and device based on Rogowski coil |
| CN114740244A (en) * | 2022-04-01 | 2022-07-12 | 核工业西南物理研究院 | Rogowski coil probe for plasma current distribution diagnosis |
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| CN102751081A (en) * | 2012-07-03 | 2012-10-24 | 深圳市创银科技股份有限公司 | Flexible coil current transformer and production method thereof |
| CN103852627A (en) * | 2012-11-30 | 2014-06-11 | 海洋王（东莞）照明科技有限公司 | Alternating-current circuit current probing device |
| CN103852626A (en) * | 2012-11-30 | 2014-06-11 | 海洋王（东莞）照明科技有限公司 | Direct current circuit detection device |
| CN104076190A (en) * | 2013-03-29 | 2014-10-01 | 海洋王（东莞）照明科技有限公司 | Direct current detection circuit |
| CN103235169A (en) * | 2013-04-25 | 2013-08-07 | 国家电网公司 | Measuring device for pre-discharging current before insulation breakthrough at VFTO (very fast transient overvoltage) |
| CN103777055A (en) * | 2013-12-03 | 2014-05-07 | 国家电网公司 | Multiple Rogowski coil parallel-connected outer integration sensor |
| CN103777055B (en) * | 2013-12-03 | 2016-06-01 | 国家电网公司 | The outer integrator sensor of multiple Luo-coil parallel connection |
| CN104297558A (en) * | 2014-10-08 | 2015-01-21 | 中国科学院电工研究所 | Current measuring device |
| CN104297558B (en) * | 2014-10-08 | 2017-08-11 | 中国科学院电工研究所 | A kind of current measuring device |
| CN104345196A (en) * | 2014-10-30 | 2015-02-11 | 南京信息工程大学 | Active weak power frequency current induction coil |
| CN106526279A (en) * | 2015-09-10 | 2017-03-22 | 赛米控电子股份有限公司 | Centering retaining device for Rogowski coil and method for arranging Rogowski coil |
| CN105448498A (en) * | 2015-12-07 | 2016-03-30 | 深圳供电局有限公司 | Traveling wave sensor and coil winding method for magnetic core for traveling wave sensor |
| CN106526302A (en) * | 2016-10-25 | 2017-03-22 | 华中科技大学 | Method for manufacturing high-performance air-core coil with balanced turns |
| CN107768904A (en) * | 2017-10-26 | 2018-03-06 | 国网宁夏电力公司检修公司 | Plug-in Rogowski coil device |
| CN108594312A (en) * | 2018-07-30 | 2018-09-28 | 吉林省电力科学研究院有限公司 | A kind of the grounded screen breakpoint detection device and method of arch form solenoid transmission coil |
| CN108594312B (en) * | 2018-07-30 | 2024-05-07 | 吉林省电力科学研究院有限公司 | Grounding grid breakpoint detection device and method for arch solenoid transmitting coil |
| CN109613316A (en) * | 2018-11-29 | 2019-04-12 | 江阴市星火电子科技有限公司 | A kind of high-precision rogowski coil |
| CN109613316B (en) * | 2018-11-29 | 2020-12-29 | 江阴市星火电子科技有限公司 | High-precision Rogowski coil |
| CN112730944A (en) * | 2020-12-19 | 2021-04-30 | 华中科技大学 | Current measuring method and device based on Rogowski coil |
| CN112730944B (en) * | 2020-12-19 | 2022-03-11 | 华中科技大学 | Current measuring method and device based on Rogowski coil |
| CN114740244A (en) * | 2022-04-01 | 2022-07-12 | 核工业西南物理研究院 | Rogowski coil probe for plasma current distribution diagnosis |
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