CN1967266A - Spiral type hollow coil current-sensing device - Google Patents
Spiral type hollow coil current-sensing device Download PDFInfo
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- CN1967266A CN1967266A CN 200610032481 CN200610032481A CN1967266A CN 1967266 A CN1967266 A CN 1967266A CN 200610032481 CN200610032481 CN 200610032481 CN 200610032481 A CN200610032481 A CN 200610032481A CN 1967266 A CN1967266 A CN 1967266A
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Abstract
The invention discloses a helical tube hollow coil current sensor, including even number, more than four, of helical tube sensing coils winding on the non-magnetic straight-shaped frame, and all helical tube sensing coils surrounding an axis with parallel symmetric distribution, and serial connecting according to limitation mode, and its configuration makes that a public electromagnetic field induces the electromotive force in all of the helical tube sensing coils to stack and mutual counteract, and it retains the two ends as the output signal ends, to form the second coil. The first coil surrounds half number of the helical tube sensing coils without mutual adjacent, to establish a single-circle or multi-circle helical tube coils, or close to each second helical tube coils to windingly make the same number of serial connecting multi-circle single-layer or multi-layer helical tube coil. The invention has the advantages of strong electromagnetic resistance interference ability, high precision, good linearity, and fast response, suitable for the production of the sensor head of electronic current transformer, and also can be used to produce the current sensor for secondary measurement, monitoring and computer protection devices of conventional current transformer.
Description
Technical field
The present invention relates to a kind of current sensor, particularly relate to and measure the spiral type hollow coil current-sensing device of using and protecting usefulness in a kind of electric system.
Background technology
At present, the current transformer that uses in electric system mainly is an electromagnetic current transducer.In order to satisfy power system development and Automation of Electric Systems, digitized needs, also developed both at home and abroad utilize other principle of induction current transformer.According to the difference of selecting sensing head for use, mainly be divided into two kinds: based on the pure optical current mutual inductor of Faraday magnetooptical effect principle with based on the electronic current mutual inductor of Rogowski (hollow) coil.
Electromagnetic current transducer is made of unshakable in one's determination and first and second winding, and its major defect has: 1, insulation technology requires complicated, inflammable easily sudden and violent.2, dynamic range is little, and frequency band is narrow, and error is big.Electromagnetic current transducer all has iron core.Along with the continuous lifting of net capacity, rated voltage is more and more higher, and short-circuit current is increasing.Under the influence of aperiodicity electric current, unshakable in one's determination can be saturated, cause the increase of the kinetic current that excitation can not be correct, can cause very big transient error, limited its measurement range.If residual flux is arranged in the iron core, can cause that more output current seriously distorts, even can cause serious consequence.3, with high costs.For the electromagnetic current transducer of UHV (ultra-high voltage), because the complexity of its insulation mode and the consumption of material, cause that it is bulky, production cost significantly increases, also brought difficulty to transportation.4, increased secondary side strict.Mainly contain: 1. the secondary side load can not be opened a way, otherwise can cause high voltage, and equipment or personnel are damaged; 2. to the burden requirement strictness, if the secondary side load is excessive, numerical value and phase angle error will increase.5, increased intermediate conversion links.The electric current of secondary output is generally the current signal of 1A or 5A, needs to change into little current signal through power pack, is input to microcomputer measurement or protective device again.6, electromagnetic current transducer is subject to shortcomings such as electromagnetic interference (EMI), maintenance workload are big, oil leaking pollution environment in addition.
Based on the pure optical current mutual inductor of Faraday magnetooptical effect principle owing to be subjected to the influence of factors such as temperature, mechanical vibration bigger, though domestic existing procucts linked network trial run, but stability, reliability is not high, and cost an arm and a leg, also have many key issues not to be resolved, therefore fail to form product and use in electric system.
Based on the electronic current mutual inductor of Rogowski (hollow) coil have that volume is little, in light weight, cost is low, no iron core, responding range is big, frequency response is wide advantage, do not have magnetic saturation and ferromagnetic oscillation problem; Also avoided the temperature and the vibration problem that exist in the pure optical sensing head.But, the hollow coil current sensing head of being developed at present that is used for electronic current mutual inductor, all be the direct center of the non magnetic annular skeleton by being wound with secondary coil with straight conductor, or secondary coil is produced on the printed circuit board (PCB) (PCB) of intermediate hollow, straight conductor is by the center of PCB.These two kinds of hollow coil current-sensing devices mainly contain two shortcomings: a little less than the coupling of (1) Primary Conductor and secondary coil, so that coefficient of mutual inductance is less, be difficult to improve coefficient of mutual inductance, otherwise can cause coil resistance, area, volume to increase by increasing coil turn and area; (2) be subject to the influence in external interference magnetic field; In addition, ring skeleton is not easy to the evenly closely coiling of sensing coil, so also can influence the precision and the anti-electromagnetic interference (EMI) of measurement.Because above these shortcomings, when existing hollow coil current sensing technology is used for the measurement of electric system three-phase current, wherein the current measurement meeting of a phase is subjected to the interference of the electromagnetic field of other biphase current generation, especially when measuring little electric current (electric system underloading), a little less than the induced signal, be vulnerable to external magnetic field again and disturb, cause measuring error bigger.
Summary of the invention
For solving existing easily saturated, the low-response of existing current sensor, the linearity is relatively poor, anti-electromagnetic interference capability is low problem, the invention provides a kind of precision height, the linearity is good, anti-electromagnetic interference capability is strong spiral type hollow coil current-sensing device.
The technical scheme that the present invention solves the problems of the technologies described above is: comprise the spiral pipe sensing coil of even number on the non magnetic straight cylindrical skeleton more than 4, all spiral pipe sensing coils are symmetrically distributed around an axis parallel, be connected in series by the mode that limits, and the feasible induction electromotive force stack that is caused in all spiral pipe sensing coils by a public electromagnetic field of its configuration is cancelled out each other, keep two terminations as output signal end, constitute secondary coil, primary winding, tightly make into a single turn or multiturn toroidal winding around half spiral pipe sensing coil not adjacent to each other
In the above-mentioned spiral type hollow coil current-sensing device, described secondary spiral pipe sensing coil all adopts the evenly close toroidal winding of making the multiturn single or multiple lift on the skeleton of identical lead, and the number of plies of shape, size and the coil of all secondary spiral pipe sensing coils and every layer of number of turn are all identical.
In the above-mentioned spiral type hollow coil current-sensing device, the cross section of described spiral pipe sensing coil on non magnetic straight cylindrical skeleton is a kind of of Any shape such as circle, 1/4 circle, rectangle, triangle.
A kind of spiral type hollow coil current-sensing device, comprise the spiral pipe sensing coil of even number on the non magnetic straight cylindrical skeleton more than 4, all spiral pipe sensing coils are symmetrically distributed around an axis parallel, be connected in series by the mode that limits, and the feasible induction electromotive force stack that is caused in all spiral pipe sensing coils by a public electromagnetic field of its configuration is cancelled out each other, keep two terminations as output signal end, constitute secondary coil; Primary winding is close to the toroidal winding that each secondary toroidal winding turns to the multiturn single or multiple lift of same number serial connection.
In the above-mentioned spiral type hollow coil current-sensing device, described secondary spiral pipe sensing coil all adopts the evenly close toroidal winding of making the multiturn single or multiple lift on the skeleton of identical lead, and the number of plies of shape, size and the coil of all secondary spiral pipe sensing coils and every layer of number of turn are all identical.
In the above-mentioned spiral type hollow coil current-sensing device, in the primary winding that a plurality of toroidal winding serial connections are made, the number of plies of all helical coil shape, size and coil and every layer of number of turn are all identical, be connected in series by the mode that limits, and its configuration makes the induction electromotive force that is once caused in the toroidal winding in institute by a public electromagnetic field superpose and cancels out each other, keeps two terminations as tested current input terminal.
Technique effect of the present invention is: 1) this spiral type hollow coil current-sensing device does not have iron core, has bandwidth, the quick advantage of response, has overcome that traditional electromagnetic type current sensor is easily saturated, low-response, the relatively poor problem of the linearity; 2) this spiral type hollow coil current-sensing device comprises a plurality of around the equally distributed spiral pipe sensing coil in center, be connected in series by the mode that limits, and the feasible induction electromotive force stack that is caused in all spiral pipe sensing coils by a public electromagnetic field of its configuration is cancelled out each other, eliminate the interference of external magnetic field, do not needed to add in addition electro-magnetic screen layer; 3) each cored screw pipe secondary coil can be made identically fully, is convenient to produce in batches, reduces cost; 4) primary winding can be close to half or all secondary toroidal windings are made spiral pipe around a circle or multiturn as required, can easily increase or reduce the coefficient of mutual inductance of current sensor.
In a word, spiral hollow coil current sensor involved in the present invention has obviously improved the saturation characteristic and the linearity of current sensor, has improved measuring accuracy and anti-electromagnetic interference capability greatly; Simple in structure, in light weight, cost is low, installs, calibrates, debugs, safeguards all very convenient.
The present invention is further illustrated below in conjunction with the drawings and specific embodiments.
Description of drawings
Fig. 1 is the vertical view of the preferred a kind of spiral type hollow coil current-sensing device of the present invention;
Fig. 2 is the construction profile of Fig. 1 hollow core coil current sensor secondary coil;
Fig. 3 is the structural representation of single spiral pipe sensing coil among Fig. 1;
The disturbing magnetic field that Fig. 4 produces near the relatively big electric current of the preferred current sensor of the present invention does not have the schematic diagram of response;
Fig. 5 is the structural representation of another embodiment of the present invention.
Fig. 6 is the structural representation of the embodiment of the invention 3.
Embodiment
Referring to Fig. 3,1 is non magnetic straight cylindrical skeleton among Fig. 3, and 2,3 is the two ends of the secondary coil on the skeleton, and wherein secondary coil adopts thinner enamel covered wire evenly close on skeleton, from the skeleton head end around to tail end, the wraparound head end repeats coiling so again, can form multilayer multiturn spiral pipe sensing coil at last, preferred coiled odd number circle, be convenient to distinguish the two ends of coil, thereby be convenient to secondary coil head end or terminal linking to each other, this point as can be seen from Figure 2 successively on the adjacent skeleton.
Among Fig. 1,4,5,6,7 are the identical spiral pipe sensing coil that is wound with secondary coil, and closely are evenly distributed on the circle around a center, and the space of being stayed is each other passed through for Primary Conductor.Primary Conductor 8 is made the spiral pipe primary winding of a circle or multiturn around the non-conterminous secondary spiral pipe of above-mentioned half sensing coil.Wherein too tight during a toroidal winding coiled multiturn, consider a spiral pipe heat radiation and with the insulation of secondary spiral pipe.In conjunction with Fig. 2, adjacent spiral pipe secondary coil is head end or terminal linking to each other successively, and 9,10 is whole secondary toroidal winding head and the tail lead end, as the output terminal of secondary induced signal.When feeding tested alternating current in the Primary Conductor, the induction electromotive force direction that 4,5,6,7 secondary coil produces is all identical, the serial connection mutual superposition, and total induction electromotive force is from 9,10 outputs.
Among Fig. 4,11,12,13 are near the electric conductor the above-mentioned spiral hollow coil current sensor of the present invention, and can pass through big electric current.When passing to alternating current in the conductor 11, relatively sensor produces the alternating magnetic field that disturbs, and 5 is opposite because of induction electromotive force equal and opposite in direction, the direction of this disturbing magnetic field generation with 6 secondary coil, cancels out each other after the serial connection; Same 4 and 7 secondary coil is also cancelled out each other because of the induction electromotive force that this disturbing magnetic field produces.When passing to alternating current in the conductor 12, relatively sensor produces the alternating magnetic field that disturbs, and 6 is opposite because of induction electromotive force equal and opposite in direction, the direction of this disturbing magnetic field generation with 7 secondary coil, and serial connection is cancelled out each other; Same 4 and 5 secondary coil is also cancelled out each other because of the induction electromotive force that this disturbing magnetic field produces.When passing to alternating current in the conductor 13, sensor produces the alternating magnetic field that disturbs relatively, 5 is identical because of the induction electromotive force direction that this disturbing magnetic field produces with 7 secondary coil, 4 is identical because of the induction electromotive force direction that this disturbing magnetic field produces with 6 secondary coil, and 5,7 secondary coil and 4,6 secondary coil is opposite because of the induction electromotive force direction that this disturbing magnetic field produces, what electric current produced in the straight again lead 13 is a linear gradient magnetic field, so 5, the induction electromotive force sum and 4 that 7 secondary coil produces because of this disturbing magnetic field, the induction electromotive force sum equal and opposite in direction that 6 secondary coil produces because of this disturbing magnetic field, direction is opposite, and final serial connection is cancelled out each other.Equally, when the related hollow coil current-sensing device of the present invention was used for the measurement of electric system three-phase current, the electromagnetic interference (EMI) that the current sensor of a certain phase also can avoid other biphase current to produce had guaranteed that promptly the measurement of three-phase current is unaffected mutually.When the interference alternating magnetic field (uniform magnetic field) of far-end generation vertically passes above-mentioned secondary coil, the half spiral pipe secondary coil of former conductor inboard is opposite because of electromotive force sum equal and opposite in direction, the direction that this disturbing magnetic field produces with its outside half spiral pipe secondary line because of the electromotive force sum that this disturbing magnetic field produces, and cancels out each other.When the external interference magnetic field levels was passed above-mentioned secondary coil, secondary coil was non-inductive.
Therefore, spiral hollow coil current sensor of the present invention disturbs electromagnetism not have response to external world.
Among Fig. 5, adopt six non magnetic straight tube skeletons, 18,19,20,21,22,23 be the identical spiral hollow coil that is wound with secondary coil, and closely be evenly distributed on the circle around a center, the space of being stayed is each other passed through for a toroidal winding 17, its winding as shown in FIG. can be around a circle or multiturn.Wherein the secondary of each spiral hollow coil coiling is as Fig. 1, and adjacent spiral hollow coil head end or end successively is connected, and not continuous cropping of Liu Yichu is the output of secondary induced signal, the connection of spiral pipe secondary coil among similar Fig. 2.
Among Fig. 6,28,29,30,31 are the identical spiral hollow coil that is wound with secondary coil, its outboard profile and connect similar Fig. 2, and serial connection constitutes secondary coil.24,25,26,27 be the identical spiral hollow coil that is wound with primary winding, its outboard profile and connect similar Fig. 2, serial connection constitutes primary winding.This method can increase the coefficient of mutual inductance of sensor greatly, and guarantees that primary winding and secondary coil all are not subjected to the interference of external magnetic field.
More than among all embodiment, each secondary toroidal winding around to also can be different, connected mode also can be made corresponding change, the induced potential stack that the connection of adjacent secondary toroidal winding should make primary winding produce at the secondary toroidal winding, the induction electromotive force stack that public electromagnetic field causes in all secondary toroidal windings is cancelled out each other, and promptly avoids the interference of external electromagnetic field.Each toroidal winding among the embodiment 3 around to also can be different, connected mode also can be made corresponding change, makes primary winding avoid the interference of external electromagnetic field equally.
Claims (6)
1, a kind of spiral type hollow coil current-sensing device, it is characterized in that: comprise the spiral pipe sensing coil of even number on the non magnetic straight cylindrical skeleton more than 4, all spiral pipe sensing coils are symmetrically distributed around an axis parallel, be connected in series by the mode that limits, and the feasible induction electromotive force stack that is caused in all spiral pipe sensing coils by a public electromagnetic field of its configuration is cancelled out each other, keep two terminations as output signal end, constitute secondary coil; Primary winding tightly makes into a single turn or multiturn toroidal winding around half spiral pipe sensing coil not adjacent to each other.
2, spiral type hollow coil current-sensing device according to claim 1, it is characterized in that: described secondary spiral pipe sensing coil all adopts the evenly close toroidal winding of making the multiturn single or multiple lift on the skeleton of identical lead, and the number of plies of shape, size and the coil of all secondary spiral pipe sensing coils and every layer of number of turn are all identical.
3, spiral type hollow coil current-sensing device according to claim 1 and 2 is characterized in that: the cross section of the spiral pipe sensing coil on the non magnetic straight cylindrical skeleton is a kind of of Any shape such as circle, 1/4 circle, rectangle, triangle.
4, a kind of spiral type hollow coil current-sensing device, it is characterized in that: comprise the spiral pipe sensing coil of even number on the non magnetic straight cylindrical skeleton more than 4, all spiral pipe sensing coils are symmetrically distributed around an axis parallel, be connected in series by the mode that limits, and the feasible induction electromotive force stack that is caused in all spiral pipe sensing coils by a public electromagnetic field of its configuration is cancelled out each other, keep two terminations as output signal end, constitute secondary coil; Primary winding is close to the toroidal winding that each secondary toroidal winding turns to the multiturn single or multiple lift of same number serial connection.
5, spiral type hollow coil current-sensing device according to claim 4, it is characterized in that: described secondary spiral pipe sensing coil all adopts the evenly close toroidal winding of making the multiturn single or multiple lift on the skeleton of identical lead, and the number of plies of shape, size and the coil of all secondary spiral pipe sensing coils and every layer of number of turn are all identical.
6, according to claim 4 or 5 described spiral type hollow coil current-sensing devices, it is characterized in that: in the primary winding that a plurality of toroidal winding serial connections are made, the number of plies of all helical coil shape, size and coil and every layer of number of turn are all identical, be connected in series by the mode that limits, and its configuration makes the induction electromotive force that is once caused in the toroidal winding in institute by a public electromagnetic field superpose and cancels out each other, keeps two terminations as tested current input terminal.
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| Application Number | Priority Date | Filing Date | Title |
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| CN 200610032481 CN1967266A (en) | 2006-10-29 | 2006-10-29 | Spiral type hollow coil current-sensing device |
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| CN 200610032481 CN1967266A (en) | 2006-10-29 | 2006-10-29 | Spiral type hollow coil current-sensing device |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103869143A (en) * | 2014-03-05 | 2014-06-18 | 西北核技术研究所 | Gas discharging current measuring device |
| CN105335613A (en) * | 2015-10-30 | 2016-02-17 | 重庆大学 | Mutual induction coefficient calculation method of PCB (printed circuit board) planar spiral coil current mutual inductor |
| CN105390261A (en) * | 2015-10-19 | 2016-03-09 | 长沙润智电源有限公司 | Anti-jamming current transformer |
| CN107037251A (en) * | 2015-11-23 | 2017-08-11 | 施耐德电器工业公司 | Current sensor and the device for measuring electric current |
| CN108761164A (en) * | 2018-04-19 | 2018-11-06 | 江苏大学 | A kind of hollow difference coil and its measurement method for impulse current measurement |
| CN109100558A (en) * | 2018-06-06 | 2018-12-28 | 中国电力科学研究院有限公司 | A kind of Rogowski coil and current measuring device |
| CN110431428A (en) * | 2017-03-16 | 2019-11-08 | 莱姆知识产权股份有限公司 | Current transducer with magnetic field gradient sensor |
| CN111837043A (en) * | 2018-01-31 | 2020-10-27 | Nl咨询公司 | Sensor for sensing instantaneous rate of change of current using galvanic isolation and integration on printed circuit board |
| CN113283255A (en) * | 2021-05-17 | 2021-08-20 | 盛视科技股份有限公司 | Card reading coil winding method, card reading device and card reading system |
| CN117330813A (en) * | 2023-09-27 | 2024-01-02 | 苏州万龙电气集团股份有限公司 | Hollow current measurement method, hybrid current transformer and circuit breaker |
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2006
- 2006-10-29 CN CN 200610032481 patent/CN1967266A/en active Pending
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103869143A (en) * | 2014-03-05 | 2014-06-18 | 西北核技术研究所 | Gas discharging current measuring device |
| CN103869143B (en) * | 2014-03-05 | 2017-06-20 | 西北核技术研究所 | A kind of gas-discharge current measurement apparatus |
| CN105390261A (en) * | 2015-10-19 | 2016-03-09 | 长沙润智电源有限公司 | Anti-jamming current transformer |
| CN105335613A (en) * | 2015-10-30 | 2016-02-17 | 重庆大学 | Mutual induction coefficient calculation method of PCB (printed circuit board) planar spiral coil current mutual inductor |
| CN105335613B (en) * | 2015-10-30 | 2018-06-29 | 重庆大学 | The mutual inductance computational methods of PCB plane solenoid current mutual inductor |
| CN107037251A (en) * | 2015-11-23 | 2017-08-11 | 施耐德电器工业公司 | Current sensor and the device for measuring electric current |
| CN110431428A (en) * | 2017-03-16 | 2019-11-08 | 莱姆知识产权股份有限公司 | Current transducer with magnetic field gradient sensor |
| CN110431428B (en) * | 2017-03-16 | 2022-07-15 | 莱姆电子(中国)有限公司 | Current transducer with magnetic field gradient sensor |
| CN111837043A (en) * | 2018-01-31 | 2020-10-27 | Nl咨询公司 | Sensor for sensing instantaneous rate of change of current using galvanic isolation and integration on printed circuit board |
| CN111837043B (en) * | 2018-01-31 | 2023-11-17 | Nl咨询公司 | Sensor for sensing instantaneous rate of change of current using electrical isolation and integration on printed circuit board |
| CN108761164A (en) * | 2018-04-19 | 2018-11-06 | 江苏大学 | A kind of hollow difference coil and its measurement method for impulse current measurement |
| CN109100558A (en) * | 2018-06-06 | 2018-12-28 | 中国电力科学研究院有限公司 | A kind of Rogowski coil and current measuring device |
| CN113283255A (en) * | 2021-05-17 | 2021-08-20 | 盛视科技股份有限公司 | Card reading coil winding method, card reading device and card reading system |
| CN113283255B (en) * | 2021-05-17 | 2024-04-02 | 盛视科技股份有限公司 | Card reading coil winding method, card reading device and card reading system |
| CN117330813A (en) * | 2023-09-27 | 2024-01-02 | 苏州万龙电气集团股份有限公司 | Hollow current measurement method, hybrid current transformer and circuit breaker |
| CN117330813B (en) * | 2023-09-27 | 2024-05-14 | 上海磊跃自动化设备有限公司 | Hollow current measurement method, hybrid current transformer and circuit breaker |
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Application publication date: 20070523 |