CN106950441A - A kind of sensor for on-line checking transformer DC magnetic bias - Google Patents

A kind of sensor for on-line checking transformer DC magnetic bias Download PDF

Info

Publication number
CN106950441A
CN106950441A CN201710081811.2A CN201710081811A CN106950441A CN 106950441 A CN106950441 A CN 106950441A CN 201710081811 A CN201710081811 A CN 201710081811A CN 106950441 A CN106950441 A CN 106950441A
Authority
CN
China
Prior art keywords
excitation
transformer
magnetic
coil
magnetic core
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN201710081811.2A
Other languages
Chinese (zh)
Other versions
CN106950441B (en
Inventor
曹建安
刘懿莹
拉菲格·汗
虞珂
张维
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Xian Jiaotong University
Original Assignee
Xian Jiaotong University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Xian Jiaotong University filed Critical Xian Jiaotong University
Priority to CN201710081811.2A priority Critical patent/CN106950441B/en
Publication of CN106950441A publication Critical patent/CN106950441A/en
Application granted granted Critical
Publication of CN106950441B publication Critical patent/CN106950441B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere

Abstract

The invention discloses a kind of sensor for on-line checking transformer DC magnetic bias, including U-shaped special-shaped magnetic core, excitation coil and detection coil are wound with respectively on U-shaped special-shaped magnetic core, and detection coil is wound in outside excitation coil, and excitation coil is connected with excitation current source.The sensor combines Fluxgate Technique and devises a special-shaped magnetic core.After inside transformer magnetic field imports sensor, D.C. magnetic field is detected using Fluxgate Technique, detection coil sensing obtains voltage, and isolated DC component then can obtain inside transformer direct current flux, judge whether transformer occurs magnetic biasing by the monitoring to direct current flux.

Description

A kind of sensor for on-line checking transformer DC magnetic bias
【Technical field】
The invention belongs to power transformer and sensor field, it is related to a kind of for on-line checking transformer DC magnetic bias Sensor.
【Background technology】
When power transformer works, iron core is in remagnetization state and non DC bias phenomenon.But in static reacance During power back-off and high voltage direct current converter, Transformer Winding compole is also easy to produce DC component, so as to cause transformer Magnetic core magnetization center of curve point shifts, i.e. DC magnetic bias phenomena.Now the waveform Severe distortion of exciting current, harmonic wave are a large amount of Produce, noise is significantly increased, transformer is overheated, and directly affects the normal work of transformer, or even cause transformer to burn.Cause This, the D.C. magnetic biasing of detection transformer core is to ensure the important measures of transformer health operation.
At present, D.C. magnetic biasing detection can use electrical measuring method, i.e.,:Electric current is used at transformer neutral point ground outlet Transformer sampled signal, directly determines whether D.C. magnetic biasing by detecting at neutral point DC current.But this method is not The magnetic bias of single-phase transformer can be detected, and when suppressing D.C. magnetic biasing using low resistance grounding method, nearby stations can be made Transformer neutral point direct current increases, and now electrical measuring method can not help operating personnel to make accurate judgement, therefore electrical measuring method is accurate Property is not high, and uses limitation.
In addition, D.C. magnetic biasing detection can also use vibration and noise sensor, extract noise during transformer work And vibration signal waveforms, contrast, determined whether with this with the transformer noise under non DC bias and vibration signal waveforms The generation of D.C. magnetic biasing.But the working condition of transformer is influenceed by factors such as power, environment temperature and service lives.When right When there is deviation than noise and rumble spectrum, it is difficult to judgment bias be as D.C. magnetic biasing cause or the factor such as temperature caused by.
【The content of the invention】
It is an object of the invention to overcome the shortcoming of above-mentioned prior art there is provided one kind to be used for on-line checking transformer dc Whether the sensor of magnetic bias, the sensor occurs D.C. magnetic biasing when can detect transformer work, by detecting the straight of transformer Flow magnetic flux to detect magnetic bias, with higher sensitivity, and on-line measurement can be realized.
To reach above-mentioned purpose, the present invention is achieved using following technical scheme:
On a kind of sensor for on-line checking transformer DC magnetic bias, including U-shaped special-shaped magnetic core, U-shaped special-shaped magnetic core Excitation coil and detection coil are wound with respectively, detection coil is wound in outside excitation coil, excitation coil and excitation current source It is connected.
The present invention is further improved:
U-shaped special-shaped magnetic core is formed by stacking by multilayer cobalt-based band, and is provided with the middle part of U-shaped magnetic core through hole, through hole or so two Side is coil-wound parts;Excitation current source is used to produce the cycle in the excitation coil that winding is connected in the magnetic core through hole left and right sides Property change, identical, the in opposite direction excitation field of size.
Excitation coil, which is connected, is wound in the magnetic core of the through hole left and right sides.
The winding direction of excitation coil ensures that when there is exciting current to flow through excitation coil through hole surrounding can form closure Toroidal magnetic field.
The coil turn that excitation coil is wound in through hole both sides magnetic core is equal.
Insulation processing is used between detection coil and excitation coil.
Compared with prior art, the invention has the advantages that:
The present invention proposes the on-line checking of transformer iron core magnetic bias will be realized, using Fluxgate Technique to judge transformer Whether magnetic bias state is operated in.Fluxgate Technique has the advantages that sensitivity is high, by its magnetic circuit phase with electrical transformer cores With reference to.The present invention applies to fluxgate sensor principle in transformer bias detection, by observing DC current in circuit Change to reflect the working condition of transformer.When transformer normal work occurs without magnetic biasing phenomenon, sensor is put into and measured, prison Slowdown monitoring circuit will show no current DC component.When magnetic biasing occurs for transformer, observation circuit will be observed that current dc component increases Plus phenomenon.The voltage device over-heat inside as caused by voltage device magnetic bias, noise can be effectively prevented to become big, energy transfer efficiency reduction The problems such as, improve transformer operating efficiency and security performance.
【Brief description of the drawings】
Fig. 1 is the operating diagram of magnetic core of transformer alternating current-direct current magnetic flux on-line checking novel sensor of the present invention.
Fig. 2 is the design drawing and pictorial diagram of magnetic core of transformer alternating current-direct current magnetic flux on-line checking novel sensor of the present invention.
Fig. 3 is exciting current in the excitation coil of magnetic core of transformer alternating current-direct current magnetic flux on-line checking novel sensor of the present invention Oscillogram.
Wherein:1-U types abnormal shape magnetic core;2- excitation coils;3- excitation current sources;4- detection coils.
【Embodiment】
The present invention is described in further detail below in conjunction with the accompanying drawings:
Referring to Fig. 1-3, the present invention combines fluxgate sensor relative theory, it is proposed that one kind is used for on-line checking transformer The sensor of D.C. magnetic biasing, and the engine request of on-line checking can be realized.The present invention includes U-shaped special-shaped magnetic core 1, U-shaped abnormal shape Excitation coil 2 and detection coil 4 are wound with magnetic core 1 respectively, detection coil 4 is wound in outside excitation coil 3, excitation coil 2 It is connected with excitation current source 3.In order to prevent from being vortexed the loss caused, U-shaped special-shaped magnetic core 1 is formed by stacking by multilayer cobalt-based band, And through hole is provided with the middle part of U-shaped magnetic core, the through hole left and right sides is coil-wound parts.It is left that the series connection of excitation coil 2 is wound in through hole The magnetic core of right both sides, winding direction need to ensure that, when there is exciting current to flow through excitation coil 2, through hole surrounding can form close ring Shape magnetic field, and it is equal to be wound in the coil turn of through hole both sides iron core.
Excitation current source 3 of the present invention is used to produce the cycle in the excitation coil 2 that winding is connected in the magnetic core through hole left and right sides Property change, identical, the in opposite direction excitation field of size.Exciting current is the certain pulse of frequency, when exciting current is reached During peak value, correspondence magnetic core internal magnetic field is up to maximum, and now sensor magnetic core reaches saturation state.
Detection coil 4 is wound in outside excitation coil 3, and needs insulation processing between excitation coil 3.Working sensor When, according to Faraday's electromagnetic induction law, the coil will induce electromotive force.Extracted using FFT or integral transformation in circuit Voltage DC component is detectable direct current flux.
The present invention is simple in construction, can monitor inside transformer working condition by examining direct current flux, improve transformer Operating efficiency and security performance.
As shown in figure 1, the present invention is made up of U-shaped special-shaped magnetic core 1, excitation coil 2, excitation current source 3 and measuring coil 4. The excitation coil series connection of two equal turn numbers is wound in the magnetic core of the through hole left and right sides, when there is exciting current to pass through, through hole four Week can form closed annular magnetic field.The magnetic field that the excitation field and transformer introduce sensor is overlapped mutually so that sensor Reach saturation state.
Inside transformer magnetic field to be measured is divided into D.C. magnetic field and AC magnetic field, when sensor is accessed into transformer to be measured, Because sensor magnetic permeability is far above transformer, magnetic field is by flow sensor in transformer, if the friendship of flow sensor Flow component and DC component be divided into and.
Fig. 2 is U-shaped special-shaped Magnetic Core Design figure and processing pictorial diagram, and silicon steel sheet uses cobalt-based material, is induction coil, and Respectively magnet exciting coil, and the two number of turn is identical.
As shown in figure 3, in the presence of exciting current, week is produced in the coil and coil of the series connection winding of the groove left and right sides Identical, the in opposite direction excitation field of the change of phase property, size.Exciting current is the certain pulse of frequency, when exciting current is reached When maximum, the magnetic field in correspondence magnetic core also reaches that maximum, i.e. sensor reach saturation state.The excitation field is enabled to The toroidal magnetic field of change is formed in sensor monolithic magnetic core.According to Faraday's electromagnetic induction law, now measuring coil will be felt Electromotive force should be gone out.In both comprising the voltage that is induced by AC magnetic field, and the DC voltage induced comprising D.C. magnetic field.
Fast Fourier Transform (FFT) is carried out to gained induced electromotive force or Integral Processing eliminates AC compounent, you can by direct current Component extraction goes out.When magnetic biasing occurs for transformer to be measured, substantially conversion will occur for DC component, you can by monitoring DC component To judge whether transformer occurs magnetic bias.
The technological thought of above content only to illustrate the invention, it is impossible to which protection scope of the present invention is limited with this, it is every to press According to technological thought proposed by the present invention, any change done on the basis of technical scheme each falls within claims of the present invention Protection domain within.

Claims (6)

1. a kind of sensor for on-line checking transformer DC magnetic bias, it is characterised in that including U-shaped special-shaped magnetic core (1), U Excitation coil (2) and detection coil (4) are wound with respectively on type abnormal shape magnetic core (1), and detection coil (4) is wound in excitation coil (3) outside, excitation coil (2) is connected with excitation current source (3).
2. the sensor according to claim 1 for on-line checking transformer DC magnetic bias, it is characterised in that U-shaped different Type magnetic core (1) is formed by stacking by multilayer cobalt-based band, and is provided with through hole in the middle part of U-shaped magnetic core, and the through hole left and right sides twines for coil Around part;Excitation current source (3) is used in the excitation coil (2) of magnetic core through hole left and right sides series connection winding produce periodically change Identical, the in opposite direction excitation field of change, size.
3. the sensor according to claim 2 for on-line checking transformer DC magnetic bias, it is characterised in that excitation line Circle (2) series connection is wound in the magnetic core of the through hole left and right sides.
4. the sensor according to claim 3 for on-line checking transformer DC magnetic bias, it is characterised in that excitation line The winding direction for enclosing (2) ensures that when there is exciting current to flow through excitation coil (2) through hole surrounding can form closed annular magnetic .
5. the sensor according to claim 4 for on-line checking transformer DC magnetic bias, it is characterised in that excitation line The coil turn that circle (2) is wound in through hole both sides magnetic core is equal.
6. the sensor according to claim 1 for on-line checking transformer DC magnetic bias, it is characterised in that detection line Enclose and insulation processing is used between (4) and excitation coil (3).
CN201710081811.2A 2017-02-15 2017-02-15 A kind of sensor for on-line checking transformer DC magnetic bias Expired - Fee Related CN106950441B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201710081811.2A CN106950441B (en) 2017-02-15 2017-02-15 A kind of sensor for on-line checking transformer DC magnetic bias

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201710081811.2A CN106950441B (en) 2017-02-15 2017-02-15 A kind of sensor for on-line checking transformer DC magnetic bias

Publications (2)

Publication Number Publication Date
CN106950441A true CN106950441A (en) 2017-07-14
CN106950441B CN106950441B (en) 2019-07-23

Family

ID=59466414

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201710081811.2A Expired - Fee Related CN106950441B (en) 2017-02-15 2017-02-15 A kind of sensor for on-line checking transformer DC magnetic bias

Country Status (1)

Country Link
CN (1) CN106950441B (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108562778A (en) * 2018-06-21 2018-09-21 深圳市航智精密电子有限公司 A kind of open type current sensor and its control method
CN109358300A (en) * 2018-09-29 2019-02-19 河南理工大学 A kind of micro fluxgate sensor based on stereochemical structure iron core
CN110389250A (en) * 2019-07-29 2019-10-29 武汉新电电气股份有限公司 A kind of device and method of for transformer D.C. magnetic biasing event early warning
CN110596480A (en) * 2019-07-09 2019-12-20 国网江苏省电力有限公司徐州供电分公司 Excitation signal injection-based transformer direct-current magnetic bias detection system and detection method thereof
CN112327224A (en) * 2020-11-02 2021-02-05 国网江苏省电力有限公司电力科学研究院 Non-closed magnetic circuit magnetic field induction electricity taking testing device and method
CN114019220A (en) * 2022-01-07 2022-02-08 北京芯可鉴科技有限公司 Current detector and circuit

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111965569B (en) * 2020-07-06 2022-06-14 南方电网科学研究院有限责任公司 DC magnetic bias level measurement method, device and system for online operation transformer

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU971618A1 (en) * 1981-05-25 1982-11-07 Курский Политехнический Институт Device for sensing contact of tool with workpiece
CN1052302C (en) * 1993-12-29 2000-05-10 住友特殊金属株式会社 DC current sensor
CN201429587Y (en) * 2009-06-19 2010-03-24 长安大学 Novel sensor for steel rail detection
CN203204135U (en) * 2013-03-28 2013-09-18 中国船舶重工集团公司第七一〇研究所 U type single magnetic core magnetic flux gate probe
CN104614690A (en) * 2014-12-18 2015-05-13 哈尔滨理工大学 Micro-array type fluxgate sensor
CN105137370A (en) * 2015-08-27 2015-12-09 无锡伊佩克科技有限公司 Low power consumption miniature fluxgate sensor
CN105866239A (en) * 2016-04-25 2016-08-17 江南大学 Detection method for U-shaped pulse fusing sensor based on ferromagnetic test piece

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU971618A1 (en) * 1981-05-25 1982-11-07 Курский Политехнический Институт Device for sensing contact of tool with workpiece
CN1052302C (en) * 1993-12-29 2000-05-10 住友特殊金属株式会社 DC current sensor
CN201429587Y (en) * 2009-06-19 2010-03-24 长安大学 Novel sensor for steel rail detection
CN203204135U (en) * 2013-03-28 2013-09-18 中国船舶重工集团公司第七一〇研究所 U type single magnetic core magnetic flux gate probe
CN104614690A (en) * 2014-12-18 2015-05-13 哈尔滨理工大学 Micro-array type fluxgate sensor
CN105137370A (en) * 2015-08-27 2015-12-09 无锡伊佩克科技有限公司 Low power consumption miniature fluxgate sensor
CN105866239A (en) * 2016-04-25 2016-08-17 江南大学 Detection method for U-shaped pulse fusing sensor based on ferromagnetic test piece

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108562778A (en) * 2018-06-21 2018-09-21 深圳市航智精密电子有限公司 A kind of open type current sensor and its control method
CN109358300A (en) * 2018-09-29 2019-02-19 河南理工大学 A kind of micro fluxgate sensor based on stereochemical structure iron core
CN109358300B (en) * 2018-09-29 2021-02-05 河南理工大学 Miniature fluxgate sensor based on spatial structure iron core
CN110596480A (en) * 2019-07-09 2019-12-20 国网江苏省电力有限公司徐州供电分公司 Excitation signal injection-based transformer direct-current magnetic bias detection system and detection method thereof
CN110389250A (en) * 2019-07-29 2019-10-29 武汉新电电气股份有限公司 A kind of device and method of for transformer D.C. magnetic biasing event early warning
CN112327224A (en) * 2020-11-02 2021-02-05 国网江苏省电力有限公司电力科学研究院 Non-closed magnetic circuit magnetic field induction electricity taking testing device and method
CN112327224B (en) * 2020-11-02 2024-02-13 国网江苏省电力有限公司电力科学研究院 Non-closed magnetic circuit magnetic field induction electricity acquisition testing device and method
CN114019220A (en) * 2022-01-07 2022-02-08 北京芯可鉴科技有限公司 Current detector and circuit

Also Published As

Publication number Publication date
CN106950441B (en) 2019-07-23

Similar Documents

Publication Publication Date Title
CN106950441B (en) A kind of sensor for on-line checking transformer DC magnetic bias
Xiang et al. Foreign object detection in a wireless power transfer system using symmetrical coil sets
Surya et al. A simplified frequency-domain detection of stator turn fault in squirrel-cage induction motors using an observer coil technique
KR102242819B1 (en) Inductive power transmitter
CN102624325B (en) Motor drive system, detection method of ground faults, and common mode choker system
CA2739898C (en) Method and device for detecting short-circuits in the stator core of electric machines
Venikar et al. Search coil based online diagnostics of transformer internal faults
Fu et al. Online condition monitoring of onboard traction transformer core based on core-loss calculation model
CN104330660A (en) Power transformer DC magnetic bias state detection method based on noise method
Cabanas et al. Insulation fault diagnosis in high voltage power transformers by means of leakage flux analysis
US9052350B2 (en) On-line monitoring system for use with electrical assets and method of operating the same
JP6642230B2 (en) DC bias detection method for transformer core and DC bias detection system for transformer core
Ding et al. Investigation of vibration impacts on HVAC transformer from HVDC system under monopole operation
CN109342877A (en) A kind of the winding interturn short-circuit fault detection means and method of fractional-slot concentratred winding magneto
US20110012637A1 (en) Method for detection of interlaminar sheet short circuits in the stator sheet core of electromachines
Beltle et al. Usability of vibration measurement for power transformer diagnosis and monitoring
He et al. Analysis and simulation on the effect of rotor interturn short circuit on magnetic flux density of turbo–generator
CN106959406A (en) For carrying out the magnetized experimental rig of generator core and its method at lower voltages
JP2012159445A (en) Dc leakage detecting device
CN109212374A (en) A kind of the winding interturn short-circuit fault detection means and method of integer slot winding permanent magnet motor
Dirani et al. Finite element simulation of hydro generators with rotor inter turn short circuit
JP6461698B2 (en) Electric leakage detection device and electric leakage detection method
CN103439405A (en) Multifunctional electromagnetic detection sensor synchronized by iron core and ferrite core and detection method thereof
CN206594260U (en) Generator core magnetic examination device under a kind of low-voltage
CN104614688A (en) C-type sensor for DC magnetic bias dynamic magnetic-flux measurement and detection method thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20190723

Termination date: 20220215

CF01 Termination of patent right due to non-payment of annual fee