CN1168992C - D.C. current sensing device - Google Patents

D.C. current sensing device Download PDF

Info

Publication number
CN1168992C
CN1168992C CNB02139203XA CN02139203A CN1168992C CN 1168992 C CN1168992 C CN 1168992C CN B02139203X A CNB02139203X A CN B02139203XA CN 02139203 A CN02139203 A CN 02139203A CN 1168992 C CN1168992 C CN 1168992C
Authority
CN
China
Prior art keywords
winding
iron core
secondary winding
wound
annular
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.)
Expired - Fee Related
Application number
CNB02139203XA
Other languages
Chinese (zh)
Other versions
CN1412568A (en
Inventor
任士焱
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.)
Huazhong University of Science and Technology
Original Assignee
Huazhong University of Science and Technology
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 Huazhong University of Science and Technology filed Critical Huazhong University of Science and Technology
Priority to CNB02139203XA priority Critical patent/CN1168992C/en
Publication of CN1412568A publication Critical patent/CN1412568A/en
Application granted granted Critical
Publication of CN1168992C publication Critical patent/CN1168992C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Landscapes

  • Transformers For Measuring Instruments (AREA)
  • Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)

Abstract

The present invention relates to a DC current sensing device which belongs to a DC current measurement device in electrotechnology. The present invention has the advantages of the DC current measurement of a commutation system of no oscillation sources, no large power drive, high precision, high stability and high reliability. The device comprises a sensing head, a power transformer, a driver transformer, a resistor, inductance, a diode, an operational amplifier and a driver, wherein the sensing head has the structure that a first annular detecting iron core and a second annular detecting iron core are respectively wound with first detecting winding and second detecting winding the number of turns of which is identical. After the assembly is finished, the outside of the sensing head is wound with compensation winding, and the integration is arranged in a screening iron core cavity the outside of which is wound with secondary winding. The present invention has both the advantages of open loop measurement and closed loop measurement, and has no oscillation brought by high voltage gain. The present invention avoids high-power drive, and has high measuring precision, high stability and strong anti-interference ability. The present invention can be widely used for the DC current online detection of the industry, such as electric smelting, electrochemistry, electroplating, electric power, electric vehicles, etc.

Description

The DC current sensing device
Technical field
The invention belongs to the dc current measurement equipment in the electrotechnics.
Background technology
The utility model patent of patent No. ZL 01219393.3 " high-precision strong direct current transducer ", no magnetic core in its sensor housing, detecting element is arranged in pairs evenly along the housing inside circumference, be filled in around the element with epoxy resin then, and detecting element is fixed in the housing.Detecting element directly detects the magnetic field that bus current produces, and by the amplification of circuit, output signal is reached with the test board data presented output signal stack of a plurality of detecting elements and is complementary.This device has the common advantage of open loop principle, and promptly the oscillation problem that does not exist the closed-loop system high voltage gain to bring does not exist for the high-power driving problem of keeping magnetic potential balance and bringing yet; Circuit, simple in structure.Shortcoming is accuracy, the poor stability of measuring, and this patent adopts no core structure in sensor housing, analyze from principle, and it can't realize being provided with infinite a plurality of detecting element, also just can't guarantee its measurement reliability; Poor anti jamming capability, particularly anti-external magnetic field is disturbed, the influence of temperature change ability.
The utility model patent of patent No. ZL 97240789.8 " dc high-current sensor ", its circuit comprise two coupling magnetic null detector acquired signal, utilize feedback technique, and the realization magnetic potential balance is measured.This device belongs to the closed-loop measuring principle, thereby has the common advantage of closed loop principle, and promptly the precision of Ce Lianging is higher, good stability; Antijamming capability is stronger.Shortcoming: there is the oscillation problem that the closed-loop system high voltage gain brings in (one) and keeps the high-power driving problem that magnetic potential balance brings; (2) circuit debugging complexity.
Summary of the invention
The invention provides the compensation DC current sensing device of a kind of magnetic potential self-balance and feedback, with the dead-beat source, the structure of no high-power driving and high precision, high stability, high reliability operation can be widely used in the measurement of commutation system DC current.
DC current sensing device of the present invention comprises sensing head, power transformer, driver transformer, resistance, diode, it is characterized in that:
(1) described sensing head structure is that the first identical annular of shape detects iron core and second annular detects iron core, be wound with the identical first detection winding and second of the number of turn respectively and detect winding, after assembly unit, their outsides are wound with the compensation winding, integral body places the toroidal cavity of shielding iron core, and the shielding iron core outside is wound with Secondary Winding;
(2) end of the same name of Secondary Winding is connected in series ground connection after first telefault, the measuring resistance successively, and Secondary Winding different name termination first diode cathode, first diode anode connect power transformer secondary winding end of the same name, this secondary winding different name end ground connection;
(3) first ends of the same name that detect winding link to each other with the second different name end that detects winding, and be connected with exciter transformer secondary winding different name end, this secondary winding end of the same name connects an end, first sample resistance another termination second diode anode and ground connection of first sample resistance and second sample resistance simultaneously, second diode cathode and first detects winding different name end and is connected, the second sample resistance other end concatenation operation amplification and driver input end and the 3rd diode anode, the 3rd diode cathode connect second and detect winding end of the same name;
(4) computing amplification and driver output end connect compensation winding different name end, compensation winding end of the same name is connected on the tie point of first telefault and measuring resistance after being connected in series second telefault.
Described DC current sensing device, described sensing head can be synthetic circular of two semi-rings, first annular iron core, the second annular detection iron core, shielding iron core, the first detection winding, the second detection winding, compensation winding and the Secondary Winding of detecting evenly arranged on two semi-rings, and each winding is electrically connected by lead between two semi-rings.
Described DC current sensing device, shielding iron core can be wound into ring-type by banded cold-reduced silicon sheet, and the annular of cavity is arranged in constituting through assembly unit.
The present invention had both had as the open loop of patent No. ZL 01219393.3 " high-precision strong direct current transducer " and had measured advantage, i.e. the oscillation problem that does not exist the closed-loop system high voltage gain to bring has also been avoided keeping magnetic potential balance and the high-power driving problem brought; The present invention also has the closed-loop measuring advantage as patent No. ZL97240789.8 " dc high-current sensor ", i.e. higher, the good stability of measuring accuracy, and antijamming capability is strong, has the characteristic of automatic tracking and compensating, complete machine ratio of performance to price height.Can be widely used in the online detection of industry DC current such as electric smelting, galvanochemistry, plating, electric power, electric vehicle.
Description of drawings
The sensing head external form figure of Fig. 1 DC current sensing device of the present invention.
Fig. 2 sensing head sectional view.
Fig. 3 DC current sensing device of the present invention circuit diagram.
Embodiment
Now the present invention is further described in conjunction with the accompanying drawings.
Shown in Figure 1, the sensing head external form of DC current sensor device be two semi-rings constitute circular, its cross section as shown in Figure 2: first annular that shape is identical detects iron core C 2Detect iron core C with second annular 3On be wound with respectively the number of turn identical first detect winding W D1, second detect winding W D2, through after the assembly unit they the outside around on compensation winding W C, then their integral body is placed shielding iron core C with toroidal cavity structure 1Cavity in, at shielding iron core C 1Outward again around last Secondary Winding W 2A winding W shown in Figure 3 1Promptly transmit measured DC I 1Bus, pass from as shown in Figure 1 sensing head center hole.
Fig. 3 has provided the circuit diagram of DC current sensing device.Secondary Winding W among the sensing head T 2End of the same name connect the secondary balancing electric current I successively 2SThe first telefault L 1, measuring resistance R SThe back links to each other the different name end and the first diode D with the earth 1Negative electrode link to each other the first diode D 1Anode and power transformer T 1The end of the same name of secondary winding link to each other, the different name end of secondary winding is connected to earth point; First detects winding WD 1End of the same name and second detect winding WD 2The different name end link to each other after, be connected to exciter transformer T 2Secondary winding different name end, its end of the same name is simultaneously with two detection signals, the first sample resistance R 1With the second sample resistance R 2An end link together; Resistance R 1The other end and the second diode D 2Anode be connected to ground, diode D simultaneously 2Negative electrode and first detect winding WD 1The different name end join; Resistance R 2The other end simultaneously with the input end of computing amplification and driver A, and the 3rd diode D 3Anode link to each other the 3rd diode D 3Negative electrode be connected to second and detect winding W D2End of the same name; The output terminal of computing amplification and driver A and compensation winding W CThe different name end link to each other the end of the same name and the second compensation electric current I of compensation winding 2CThe second telefault L 2An end link to each other, the other end is connected to the first telefault L 1With measuring resistance R SOn the node of series connection.
After this device puts into operation, by power transformer T 1Through diode D 1The half-wave current Secondary Winding W that flows through is provided 2, in half period by shielding iron core C 1With Secondary Winding W 2, set up the secondary balancing electric current I automatically 2SWith primary measured current I 1Between the direct current magnetic potential balance, this magnetic potential balance is that it has avoided the use high-power electronic device to drive the secondary balancing electric current I by the decision of the characteristic of the approximate rectangular magnetization curve of iron core 2SActive method, and realize the direct current magnetic potential balance.It is different from the direct current magnetic potential balance that is made of high open-loop voltage gain (generally greater than 1000 times), PID governing loop and high-power driven source driving in the traditional closed loop system, thereby does not have the vibration and the high-power driving problem of system.Because this magnetic potential balance does not generally have the degree of accuracy height of closed-loop system magnetic potential balance, the present invention reasonably becomes core design the center cavity structure, at shielding iron core C 1Zero ampere-turn is set in the cavity detects iron core C 2, C 3With detection winding W D1, W D2Poor in order to the ampere-turn that detects above-mentioned direct current magnetic potential balance in this semiperiod.Through exciter transformer T 2After excitatory, detect winding W D1, W D2Output current signal through diode D 2, D 3With the sample of signal resistance R 1, R 2And computing amplification and driver A, output DC compensation electric current I 2CFeed back to compensation winding W CThereby, realize detecting iron core C 2, C 3The compensation of direct current zero ampere-turn, kept high-precision direct current magnetic potential balance.The present invention is because of primary measured current I 1Magnetic potential W 1I 1, the overwhelming majority is by Secondary Winding W 2By ac power transformer T 1The electric current magnetic potential W that provides 2I 2SSelf-poise is fallen, by residue magnetic potential W 1I 1-W 2I 2SThe offset current I that produces 2CJust very little, the power consumption of computing amplification and driver A is little, and reliability height, price are also low.More meaningfully, detect iron core C 2, C 3, detect winding W D1, W D2, compensation winding W C, the offset current feedback system that constitutes such as electronic module A, it is the direct current self compensating system of a low-voltage enlargement factor, rather than the closed loop feedback system of high voltage enlargement factor formation, thereby the oscillation problem that does not also exist the closed-loop system high voltage gain to bring, yet the offset current I of this feedback system 2CThe characteristic that still has the closed-loop system automatic tracking and compensating.Though it is to be operated under the situation of half period the secondary balancing electric current I that this direct current magnetic potential balance flows back to the feedback bucking-out system with difference 2SWith the second compensation electric current I 2CThe filter inductor of flowing through respectively L 1And L 2After, can obtain desirable direct current.The secondary balancing electric current I 2SWith the second compensation electric current I 2CBy measuring resistance R SSuperpose, obtain the secondary current I of this DC current sensing device 2=I 2S+ I 2CThereby, realize secondary ampere-turn W 2I 2With a direct current ampere-turn W 1I 1Magnetic potential balance W almost completely 2I 2≈ W 1I 1, the number of turn of measured DC bus is 1 circle, i.e. W usually 1=1, Secondary Winding W 2With compensation winding W CThe number of turn identical, i.e. W 2=W CBe multiturn, so the little electric current I of secondary 2=(W 1/ W 2) I 1Represent tested once big electric current exactly, coefficient of ratio W 1/ W 2For once with the turn ratio of Secondary Winding, be a constant.Secondary current I 2Flow through measuring resistance R S, on measuring resistance, obtain magnitude of voltage I 2R S, to meet the demands with the digital implementation of voltage signal output, computer sampling etc.

Claims (3)

1. a DC current sensing device comprises sensing head, power transformer, driver transformer, resistance, diode, it is characterized in that:
(1) described sensing head structure is that the first identical annular of shape detects iron core and second annular detects iron core, be wound with the identical first detection winding and second of the number of turn respectively and detect winding, after assembly unit, the first detection winding and second detects the winding outside and is wound with the compensation winding, integral body places the toroidal cavity of shielding iron core, and the shielding iron core outside is wound with Secondary Winding;
(2) end of the same name of Secondary Winding is connected in series ground connection after first telefault, the measuring resistance successively, and Secondary Winding different name termination first diode cathode, first diode anode connect power transformer secondary winding end of the same name, this secondary winding different name end ground connection;
(3) first ends of the same name that detect winding link to each other with the second different name end that detects winding, and be connected with exciter transformer secondary winding different name end, this secondary winding end of the same name connects an end of first sample resistance and second sample resistance simultaneously, first sample resistance another termination second diode anode and ground connection, second diode cathode and first detects winding different name end and is connected, the second sample resistance other end concatenation operation amplification and driver input end and the 3rd diode anode, the 3rd diode cathode connect second and detect winding end of the same name;
(4) computing amplification and driver output end connect compensation winding different name end, compensation winding end of the same name is connected on the tie point of first telefault and measuring resistance after being connected in series second telefault.
2. DC current sensing device as claimed in claim 1, it is characterized in that described sensing head is synthetic circular of two semi-rings, first annular iron core, the second annular detection iron core, shielding iron core, the first detection winding, the second detection winding, compensation winding and the Secondary Winding of detecting evenly arranged on two semi-rings, and each winding is electrically connected by lead between two semi-rings.
3. DC current sensing device as claimed in claim 1 or 2 is characterized in that shielding iron core is wound into ring-type by banded cold-reduced silicon sheet, has the annular of cavity in constituting through assembly unit.
CNB02139203XA 2002-10-25 2002-10-25 D.C. current sensing device Expired - Fee Related CN1168992C (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CNB02139203XA CN1168992C (en) 2002-10-25 2002-10-25 D.C. current sensing device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CNB02139203XA CN1168992C (en) 2002-10-25 2002-10-25 D.C. current sensing device

Publications (2)

Publication Number Publication Date
CN1412568A CN1412568A (en) 2003-04-23
CN1168992C true CN1168992C (en) 2004-09-29

Family

ID=4749953

Family Applications (1)

Application Number Title Priority Date Filing Date
CNB02139203XA Expired - Fee Related CN1168992C (en) 2002-10-25 2002-10-25 D.C. current sensing device

Country Status (1)

Country Link
CN (1) CN1168992C (en)

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100433491C (en) * 2005-07-29 2008-11-12 华中科技大学 Magnetic potential balance controllable adjustable reactor
WO2009009878A1 (en) * 2007-07-13 2009-01-22 Kinects Solutions Inc. Transformer meter and system for using same
CN101593618B (en) * 2008-05-29 2011-11-02 栢怡国际股份有限公司 Inductor with current sensing function and circuit thereof
CN102136342B (en) * 2010-12-29 2012-09-26 浙江南瑞科技有限公司 Circuit for driving electromagnet at high speed
CN103308743B (en) * 2013-05-24 2015-05-06 华中科技大学 Direct current metering device
CN103487632A (en) * 2013-10-11 2014-01-01 上海飞轩电子有限公司 Shielded open loop type magnetic gathering ring-free tunneling magnetoresistive sensor
CN104198796B (en) * 2014-08-22 2019-03-12 安阳师范学院 D.C. current detecting circuit and method based on transformer
CN107942123B (en) * 2017-12-14 2024-02-02 华中科技大学 Direct current measuring device
CN108490239B (en) * 2018-03-16 2023-10-24 华中科技大学 Transient current measuring device
CN108226610B (en) * 2018-03-16 2023-12-26 华中科技大学 Clamp type measuring device for alternating current and direct current small current
CN111381084B (en) * 2020-01-16 2021-06-29 华中科技大学 Stray parameter becomes more meticulous adjustable high frequency current sensor
CN113030557B (en) * 2021-03-11 2023-06-27 北京动力源科技股份有限公司 Current detection circuit and current detection method

Also Published As

Publication number Publication date
CN1412568A (en) 2003-04-23

Similar Documents

Publication Publication Date Title
CN1243248C (en) Current sensor
CN1168992C (en) D.C. current sensing device
CN1021134C (en) Current intensity transformer device for measuring variable electric current
CN103308743A (en) Direct current metering device
CN102445583B (en) Voltage signal monitoring device of power energy quality monitoring device and circuit as well as application thereof
CN111323737B (en) Impedance sensitive type magnetic sensor and hardware detection circuit thereof
CN1267734C (en) Double detection type current sensor
CN2583682Y (en) Direct current sensor
CN109975616A (en) A kind of wide-range high-precision resistance meter
CN102436995B (en) Hall high voltage detection control method applied to traveling wave tube program control high voltage power supply
CN101571557B (en) DC high-current metering device
CN111474399A (en) High-voltage side large-current precise sampling conversion circuit
CN2670951Y (en) Current sensor
CN206649051U (en) Digital acceleration measurement apparatus with constant current source power supply
CN212658806U (en) Online battery internal resistance measuring device
Ghislanzoni et al. A DC current transformer for large bandwidth and high common-mode rejection
CN214585665U (en) Multi-shunt current sampling circuit, current measuring device and battery pack
CN212134792U (en) Balanced symmetrical sampling circuit of direct current electric meter
CN213633620U (en) Loop resistance tester
CN2689240Y (en) Double detecting current sensors
CN208939925U (en) A kind of analog to digital conversion circuit with linear isolation characteristic
CN112526412A (en) Method and system for testing polarity of current transformer of transformer lifting seat
CN1006007B (en) Multichannel open-type heavy d.c. comparator
CN111650526A (en) Online battery internal resistance measuring device and method
CN214201590U (en) Array sensor measuring circuit

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
C19 Lapse of patent right due to non-payment of the annual fee
CF01 Termination of patent right due to non-payment of annual fee