CN116338276A - Measurement system for transient current - Google Patents
Measurement system for transient current Download PDFInfo
- Publication number
- CN116338276A CN116338276A CN202211688568.8A CN202211688568A CN116338276A CN 116338276 A CN116338276 A CN 116338276A CN 202211688568 A CN202211688568 A CN 202211688568A CN 116338276 A CN116338276 A CN 116338276A
- Authority
- CN
- China
- Prior art keywords
- tmr
- shell
- feedback
- measurement system
- current sensor
- 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.)
- Pending
Links
- 238000005259 measurement Methods 0.000 title claims abstract description 59
- 230000001052 transient effect Effects 0.000 title claims abstract description 34
- 238000012545 processing Methods 0.000 claims abstract description 33
- 238000001914 filtration Methods 0.000 claims abstract description 5
- 230000002401 inhibitory effect Effects 0.000 claims abstract description 5
- 238000004804 winding Methods 0.000 claims description 31
- 238000005070 sampling Methods 0.000 claims description 16
- 239000000463 material Substances 0.000 claims description 9
- 230000002093 peripheral effect Effects 0.000 claims description 8
- 230000006978 adaptation Effects 0.000 claims description 3
- 238000010030 laminating Methods 0.000 claims 1
- 230000004907 flux Effects 0.000 description 11
- 238000000034 method Methods 0.000 description 10
- 230000005389 magnetism Effects 0.000 description 9
- 230000008569 process Effects 0.000 description 7
- 238000010586 diagram Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- LVROLHVSYNLFBE-UHFFFAOYSA-N 2,3,6-trichlorobiphenyl Chemical compound ClC1=CC=C(Cl)C(C=2C=CC=CC=2)=C1Cl LVROLHVSYNLFBE-UHFFFAOYSA-N 0.000 description 4
- 230000035699 permeability Effects 0.000 description 4
- 230000035945 sensitivity Effects 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 229910000889 permalloy Inorganic materials 0.000 description 2
- 230000005641 tunneling Effects 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 230000003313 weakening effect Effects 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/0046—Arrangements for measuring currents or voltages or for indicating presence or sign thereof characterised by a specific application or detail not covered by any other subgroup of G01R19/00
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
Abstract
The invention relates to a measurement system for transient current, which comprises an electromagnetic shielding shell and a measurement device; the electromagnetic shielding shell is enclosed to form a containing cavity, the measuring device is contained in the containing cavity, and the electromagnetic shielding shell is used for inhibiting external electromagnetic interference; the measuring device comprises a TMR current sensor, a feedback assembly, a signal processing circuit and a PCB (printed circuit board), wherein the TMR current sensor, the feedback assembly and the signal processing circuit are all arranged on the PCB, the TMR current sensor is electrically connected with the feedback assembly, and the feedback assembly is electrically connected with the signal processing circuit; the signal processing circuit is used for converting the voltage signal output by the feedback component into a digital signal for output after filtering and amplifying the voltage signal; by arranging the electromagnetic shielding shell, the shielding effectiveness of the TMR current sensor is improved, and the measurement range of the TMR current sensor is enlarged; meanwhile, the measurement accuracy of the TMR current sensor is improved.
Description
Technical Field
The invention relates to the technical field of current metering, in particular to a measurement system for transient current.
Background
At present, current measurement is of great significance to monitoring of the running state of the power grid and parameter measurement, and along with the gradual development of the intelligent power grid, the current measurement requirement is improved. Because the measured objects and the application scenes are increasingly complex and various, the amplitude and the frequency span of the current to be measured are very large, and in order to adapt to the requirements, the current sensor rapidly develops.
The magnetic sensor can reversely push the current to be measured by measuring the magnetic field generated by the current, and provides possibility for realizing the current sensor which can be used for measuring alternating current, direct current and impact current at the same time. The tunneling magneto-resistance (TMR) current sensor is used as a Hall current sensor, is a novel magneto-resistance sensor behind an Anisotropic (AMR) current sensor and a giant magneto-resistance (GMR) current sensor, and has the advantages of high sensitivity, wide linear range and the like.
However, since the magnetic fields have superposition properties, and the TMR current sensor has high sensitivity, it is easily affected by a nearby large current, an environmental magnetic field, etc. when the measurement is performed, and it is difficult to adapt to a complicated field working environment. The magnetic field measured by the TMR chip can be more concentrated by adopting the magnetic focusing ring, the anti-interference capability of the TMR current transformer is improved to a certain extent, the chip is easy to saturate, and the measurement range of the TMR current sensor is limited. The closed loop control makes the TMR chip work in zero magnetic flux state, but consumes larger power consumption. How to simultaneously consider the anti-interference capability and the measurement range of the TMR current sensor, and reduce the power consumption required by closed-loop control as much as possible so as to ensure the accuracy and the reliability of the measurement result, and the problem to be solved is urgent.
Disclosure of Invention
Aiming at the defects existing in the prior art, the invention aims to provide a transient current measurement system, which has the advantages that the shielding effectiveness of a TMR current sensor can be improved, and the measurement range of the TMR current sensor is enlarged; meanwhile, the closed loop feedback efficiency is improved, so that the accuracy and the reliability of the measurement result of the TMR current sensor are ensured.
The above object of the present invention is achieved by the following technical solutions: a measurement system for transient current comprises an electromagnetic shielding shell and a measurement device; the electromagnetic shielding shell is enclosed to form a containing cavity, the measuring device is contained in the containing cavity, and the electromagnetic shielding shell is used for inhibiting external electromagnetic interference; the measuring device comprises a TMR current sensor, a feedback assembly, a signal processing circuit and a PCB board, wherein the TMR current sensor, the feedback assembly and the signal processing circuit are all arranged on the PCB board, the TMR current sensor is electrically connected with the feedback assembly, and the feedback assembly is electrically connected with the signal processing circuit; the TMR current sensor is used for converting a magnetic field difference value generated by the current to be detected and the feedback current into a voltage signal to be output, and the output voltage signal controls the feedback component; the feedback component is used for realizing closed-loop control; the signal processing circuit is used for converting the voltage signal output by the feedback component into a digital signal for output after filtering and amplifying.
Preferably, the measurement system for transient current provided by the invention comprises a circular part and a rectangular part, wherein an arc-shaped groove matched with the circular part is formed at one end of the rectangular part, the bottom end of the circular part is inserted into the arc-shaped groove, and the outer peripheral wall of the circular part is connected with the inner peripheral wall of the arc-shaped groove.
Preferably, the TMR current sensor provided by the invention comprises a magnetic flux collecting ring and 2n TMR chips, wherein n is a natural number greater than or equal to 1, and the magnetic flux collecting ring and the 2n TMR chips are arranged on one side of the circular part.
Preferably, in the measurement system for transient current provided by the invention, the magnetic flux collecting ring comprises 2n arc plates, wherein n is a natural number greater than or equal to 1, the 2n arc plates are arranged at intervals around the circumference of the circular part, a gap is arranged between every two adjacent arc plates, the 2n arc plates form 2n gaps, the TMR chips are arranged in a one-to-one correspondence with the gaps, and the 2n TMR chips are respectively arranged in the 2n gaps.
Preferably, the feedback assembly comprises a feedback winding, a control circuit, an output circuit and a sampling resistor, wherein the feedback winding is wound on the circular part and the magnetic focusing ring, and the control circuit, the output circuit and the sampling resistor are integrated on the rectangular part; the control circuit is coupled between the TMR chip and the output circuit, the output circuit is connected with the feedback winding, the feedback winding is connected with the sampling resistor, and the sampling resistor is connected with the signal processing circuit.
Preferably, the electromagnetic shielding shell comprises a body and a cover plate, wherein an opening is formed in the bottom end of the body, the body is enclosed to form the accommodating cavity, the opening is communicated with the accommodating cavity, and the cover plate is covered at the opening so that the accommodating cavity is closed.
Preferably, the body of the transient current measurement system provided by the invention comprises an outer shell and an inner shell, wherein the outer shell is enclosed to form a cavity, the inner shell is enclosed to form the accommodating cavity, the inner shell is inserted into the cavity, and the outer wall of the inner shell is attached to the inner wall of the cavity.
Preferably, in the measurement system for transient current provided by the invention, the inner shell comprises a first shell and a second shell, one side of the first shell is buckled on the second shell, and the first shell and the second shell are jointly enclosed to form the accommodating cavity; the bottom of first casing has seted up first logical groove, the bottom of second casing seted up with first logical groove looks adaptation's second logical groove, first logical groove with the second logical groove corresponds the setting, first logical groove with the second logical groove constitutes jointly the opening.
Preferably, in the transient current measurement system provided by the invention, a protrusion is arranged on one side of the first shell facing the second shell, a clamping groove matched with the protrusion is arranged on one side of the second shell facing the first shell, and the protrusion is inserted into the clamping groove so that the first shell is connected with the second shell.
Preferably, in the transient current measurement system provided by the invention, the outer shell is made of a high-conductivity material, and the inner shell is made of a high-permeability material.
In summary, the beneficial technical effects of the invention are as follows: the transient current measurement system comprises an electromagnetic shielding shell and a measurement device; the electromagnetic shielding shell is enclosed to form a containing cavity, the measuring device is contained in the containing cavity, and the electromagnetic shielding shell is used for inhibiting external electromagnetic interference; the measuring device comprises a TMR current sensor, a feedback assembly, a signal processing circuit and a PCB (printed circuit board), wherein the TMR current sensor, the feedback assembly and the signal processing circuit are all arranged on the PCB, the TMR current sensor is electrically connected with the feedback assembly, and the feedback assembly is electrically connected with the signal processing circuit; the TMR current sensor is used for converting a magnetic field difference value generated by the current to be detected and the feedback current into a voltage signal to be output, and the output voltage signal controls the feedback component; the feedback component is used for realizing closed-loop control; the signal processing circuit is used for converting the voltage signal output by the feedback component into a digital signal for output after filtering and amplifying the voltage signal; by arranging the electromagnetic shielding shell, the shielding effectiveness of the TMR current sensor is improved, and the measurement range of the TMR current sensor is enlarged; meanwhile, the measurement accuracy of the TMR current sensor is improved.
Drawings
Fig. 1 is a schematic diagram of an overall structure of a transient current measurement system according to an embodiment of the present invention.
Fig. 2 is a block diagram of a transient current measurement system according to an embodiment of the present invention.
Fig. 3 is a schematic structural diagram of a magnetic flux collecting ring in a transient current measurement system according to an embodiment of the present invention.
Fig. 4 is a front view of a connection structure of a TMR current sensor, a feedback winding and a PCB board in a measurement system for transient current according to an embodiment of the present invention.
Fig. 5 is a side view of a connection structure of a TMR current sensor, a feedback winding and a PCB board in a measurement system for transient current according to an embodiment of the present invention.
Fig. 6 is a schematic diagram of a connection structure between a feedback winding and a PCB board in a measurement system for transient current according to an embodiment of the present invention.
Fig. 7 is a schematic structural diagram of an inner case in a transient current measurement system according to an embodiment of the present invention.
Fig. 8 is a cross-sectional view of an inner housing in a measurement system for transient current according to an embodiment of the present invention.
In the figure, 1, a measuring system; 10. an electromagnetic shield case; 11. a body; 111. an opening; 1111. a first through groove; 1112. a second through slot; 112. an inner case; 1121. a receiving chamber; 1122. a first housing; 1123. a second housing; 1124. a protrusion; 113. a housing; 20. a measuring device; 21. TMR current sensor; 211. a magnetic ring; 2111. an arc plate; 2112. a slit; 212. TMR chip; 22. a feedback assembly; 221. a feedback winding; 23. a signal processing circuit; 24. a PCB board; 241. a circular portion; 242. rectangular parts.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
Referring to fig. 1 and 2, a transient current measurement system 1 according to the present invention includes an electromagnetic shielding case 113 and a measurement device 20; the electromagnetic shielding shell 113 encloses a receiving cavity 1121, the measuring device 20 is received in the receiving cavity 1121, and the electromagnetic shielding shell 113 is used for suppressing external electromagnetic interference.
In particular, the shape of the receiving cavity 1121 is adapted to the shape of the measuring device 20.
The measurement device 20 comprises a TMR (tunneling magneto resistance) current sensor, a feedback component 22, a signal processing circuit 23 and a PCB (printed circuit board) 24, wherein the TMR current sensor 21, the feedback component 22 and the signal processing circuit 23 are all arranged on the PCB 24, the TMR current sensor 21 is electrically connected with the feedback component 22, and the feedback component 22 is electrically connected with the signal processing circuit 23; the TMR current sensor 21 is configured to convert a magnetic field difference value generated by the current to be measured and the feedback current into a voltage signal for outputting, and the output voltage signal controls the feedback component 22; the feedback assembly 22 is used to implement closed loop control; the signal processing circuit 23 is configured to perform filtering and amplifying processing on the voltage signal output by the feedback component 22, and then convert the voltage signal into a digital signal for output; by providing electromagnetic shield case 113, thereby, the shielding effectiveness of TMR current sensor 21 is improved, and the measurement range of TMR current sensor 21 is increased; at the same time, the measurement accuracy of TMR current sensor 21 is improved.
Specifically, feedback component 22 is coupled between TMR current sensor 21 and the processing circuit.
With continued reference to fig. 4 and 5, in this embodiment, the PCB 24 includes a circular portion 241 and a rectangular portion 242, one end of the rectangular portion 242 is provided with an arc slot adapted to the circular portion 241, the bottom end of the circular portion 241 is inserted into the arc slot, and the outer peripheral wall of the circular portion 241 is connected with the inner peripheral wall of the arc slot.
Specifically, the outer peripheral wall of the circular portion 241 is bonded to the inner peripheral wall of the arcuate groove.
For example, the circular portion 241 may be integrally formed with the rectangular portion 242 by cutting, and the circular portion 241 and the rectangular portion 242 may be connected by welding, which is not limited in this embodiment.
Wherein TMR current sensor 21 is disposed on circular portion 241, feedback assembly 22 is partially disposed on circular portion 241, the remainder of feedback assembly 22 is disposed on rectangular portion 242, and signal processing circuit 23 is disposed on rectangular portion 242.
Specifically, the circular portion 241 is provided with a through hole, the through hole extends along the central axis direction of the circular portion 241, and the central axis of the through hole is parallel to the central axis of the circular portion 241.
Further, in the present embodiment, TMR current sensor 21 includes magnetism collecting ring 211 and 2n TMR chips 212, where n is a natural number equal to or greater than 1, and magnetism collecting ring 211 and 2n TMR chips 212 are disposed on one side of circular portion 241.
Specifically, the central axis of the magnetic focusing ring 211 is parallel to the central axis of the circular portion 241, and in some realizable manners, the central axis of the magnetic focusing ring 211 is arranged in line with the central axis of the circular portion 241. The 2n TMR chips 212 are arranged at intervals along the circumferential direction of the circular portion 241.
Wherein, 2n TMR chips 212 and magnetism collecting ring 211 are all disposed on the same side of circular portion 241.
With continued reference to fig. 3 to 4, in the present embodiment, the magnetism collecting ring 211 includes 2n arc plates 2111, where n is a natural number greater than or equal to 1, the 2n arc plates 2111 are circumferentially spaced around the circular portion 241, a gap 2112 is formed between every two adjacent arc plates 2111, the 2n arc plates 2111 form 2n gaps 2112, the TMR chips 212 are arranged in a one-to-one correspondence with the gaps 2112, and the 2n TMR chips 212 are respectively arranged in the 2n gaps 2112; on the one hand, by arranging 2n arc plates 2111, the magnetic field excited by the current to be measured at the measuring position of TMR chip 212 is more concentrated, thereby being beneficial to improving the sensitivity of TMR current sensor 21 and having a certain shielding effect on the interference magnetic field; on the other hand, by providing slit 2112 between adjacent two circular arc plates 2111, the magnetic resistance on the entire magnetic path of magnetism collecting ring 211 is thereby increased, saturation of TMR chip 212 is prevented, and the measurement range of the TMR sensor is increased.
Specifically, magnetic flux collecting ring 211 is made of a material with as high a magnetic permeability as possible, so that the sensitivity of TMR current sensor 21 is improved, and the characteristics of TMR chip 212 are matched to prevent the chip from exceeding the range.
Wherein 2n TMR chips 212 are placed in 2n slits 2112, respectively, and welded on circular portion 241. The sensitive axis direction of TMR chip 212 is perpendicular to the radial direction of circular portion 241.
The number of slits 2112 and the number of TMR chips 212 are the same as the number of circular arc portions.
In this embodiment, magnetism collecting ring 211 includes 4 circular arc plates 2111,4 circular arc plates 2111 constituting 4 slits 2112,4 TMR chips 212 respectively placed in 4 slits 2112.
For example, the arc plate 2111 may be made of permalloy, and of course, other materials having high magnetic permeability may be used for the arc plate 2111.
With continued reference to fig. 4 to 6, in the present embodiment, the feedback assembly 22 includes a feedback winding 221, a control circuit, an output circuit and a sampling resistor, the feedback winding 221 is wound on the circular portion 241 and the magnetic focusing ring 211, and the control circuit, the output circuit and the sampling resistor are integrated on the rectangular portion 242; the control circuit is coupled between TMR chip 212 and the output circuit, the output circuit is connected with feedback winding 221, feedback winding 221 is connected with sampling resistor, sampling resistor is connected with signal processing circuit 23; by arranging the control circuit, the control circuit is used for controlling the output circuit to generate feedback current, and finally, the magnetic flux in the magnetic focusing ring 211 is zero, so that closed-loop control is realized, and therefore, the magnetic focusing ring 211 is prevented from being saturated or the TMR chip 212 is prevented from exceeding the range, and the measurement range and the accuracy of the TMR sensor are improved.
Specifically, a part of the feedback winding 221 is wound on the circular portion 241, and another part of the feedback winding 221 is wound on the magnetism collecting ring 211 and then welded with the feedback winding 221 wound on the circular portion 241, so as to form a complete feedback winding 221 coil together. The number of turns of the feedback winding 221 wound on each arc plate 2111 is the same, so that the magnetic field distribution in the magnetic flux collecting ring 211 is more uniform, and when the same current is measured, the feedback winding 221 distributed winding of the closed loop control has smaller required feedback current and higher negative feedback efficiency compared with concentrated winding, thereby being beneficial to reducing the power consumption of the closed loop TMR current sensor 21.
The feedback winding 221 wound on the circular portion 241 may be disposed on a side of the circular portion 241 facing away from the magnetic focusing ring 211, or the feedback winding 221 wound on the circular portion 241 may be disposed on a side of the circular portion 241 facing toward the magnetic focusing ring 211, which is not limited in this embodiment.
In the use process, the current to be measured excites the magnetic field, the TMR current sensor 21 converts the difference between the magnetic field generated by the current to be measured and the magnetic field generated by the feedback current in the feedback winding 221 into a voltage signal to be output (namely, the direction of the magnetic field excited by the feedback current in the feedback winding 221 is opposite to that of the magnetic field generated by the current to be measured passing through the center of the magnetic flux focusing ring 211, the difference between the two is converted into a voltage signal to be output by the TMR chip 212), the average value of the voltage signals output by the 2n TMR chips 212 is output with the feedback current after passing through the control circuit and the output circuit, the feedback current flows through the feedback winding 221 to generate the feedback magnetic field, the feedback current is not changed any more after the feedback magnetic field and the magnetic field of the current to be measured are balanced, and the magnetic flux focusing ring 211 reaches a zero state. The feedback current is converted into a voltage output via a sampling resistor connected to the feedback winding 221. Thus, the magnitude of the current to be measured can be calculated.
It should be noted that the signal processing circuit, the control circuit, the output circuit and the sampling resistor are well known to those skilled in the art, and the structures of the signal processing circuit, the control circuit, the output circuit and the sampling resistor are not described in detail herein.
With continued reference to fig. 7 and 8, in the present embodiment, the electromagnetic shielding shell 113 includes a body 11 and a cover plate, the bottom end of the body 11 is provided with an opening 111, the body 11 encloses a containing cavity 1121, the opening 111 is communicated with the containing cavity 1121, and the cover plate is covered at the opening 111, so that the containing cavity 1121 is closed; the body 11 comprises an outer shell 113 and an inner shell 112, wherein the outer shell 113 is enclosed into a cavity, the inner shell 112 is enclosed into a containing cavity 1121, the inner shell 112 is inserted into the cavity, and the outer wall of the inner shell 112 is attached to the inner wall of the cavity; by providing two shells of the outer shell 113 and the inner shell 112, the anti-interference effect is improved.
Wherein, the outer shell 113 is made of high conductivity material, the inner shell 112 is made of high magnetic permeability material, and in the use process, the outer shell 113 has larger reflection loss to the external interference magnetic field, so that the high magnetic permeability material of the inner shell 112 can be prevented from weakening the shielding effect due to magnetic saturation when the interference magnetic field is stronger.
Illustratively, the outer shell 113 is copper and the inner shell 112 is permalloy.
In the use process, the cover plate is provided with a wire outlet hole matched with the wire outlet cable. The measuring device 20 is accommodated in the accommodating cavity 1121, and the wire outgoing cable on the measuring device 20 passes through the wire outgoing hole and out of the accommodating cavity 1121.
Further, in the present embodiment, the inner shell 112 includes a first shell 1122 and a second shell 1123, one side of the first shell 1122 is fastened on the second shell 1123, and the first shell 1122 and the second shell 1123 together enclose a receiving cavity 1121; the bottom end of the first shell 1122 is provided with a first through groove 1111, the bottom end of the second shell 1123 is provided with a second through groove 1112 adapted to the first through groove 1111, the first through groove 1111 and the second through groove 1112 are correspondingly arranged, and the first through groove 1111 and the second through groove 1112 together form the opening 111.
Taking the orientation shown in fig. 7 as an example, the first housing 1122 is located at an upper portion of the second housing 1123.
Specifically, the first through groove 1111 communicates with the cavity of the first housing 1122, and the second through groove 1112 communicates with the cavity of the second housing 1123. The first and second cases 1122 and 1123 each have a C-shaped cross-section with a plane parallel to the central axis of the circular portion 241.
In use, the opening 111 end of the first housing 1122 is fastened to the opening 111 end of the second housing 1123, so that the first housing 1122 and the second housing 1123 define a receiving cavity 1121.
The structure of the outer casing 113 is substantially identical to that of the inner casing 112, and the structure of the outer casing 113 is not described herein.
Further, in the present embodiment, a protrusion 1124 is disposed on a side of the first housing 1122 facing the second housing 1123, a slot adapted to the protrusion 1124 is disposed on a side of the second housing 1123 facing the first housing 1122, and the protrusion 1124 is inserted into the slot to connect the first housing 1122 and the second housing 1123.
Specifically, the clamping groove extends around the circumference of the second housing 1123, the protrusion 1124 extends around the circumference of the first housing 1122, and in use, the protrusion 1124 is inserted into the clamping groove, and the outer circumferential wall of the protrusion 1124 is attached to the inner circumferential wall of the clamping groove.
In order to further improve the connection strength between the first and second cases 1122 and 1123, the first and second cases 1122 and 1123 are increased in bolt connection on the basis of the connection of the protrusions 1124 and the clamping grooves, thereby improving the shielding effect of the electromagnetic shield case 113.
The use process of the transient current measurement system 1 provided in this embodiment is as follows: the magnetic field excited by the feedback current in the feedback winding 221 is opposite to the magnetic field generated by the current to be detected passing through the center of the magnetism collecting ring 211, the difference value of the magnetic field and the magnetic field is converted into a voltage signal by the TMR chip 212 to be output, the average value of the voltage signals output by the 2n TMR chips 212 passes through the control circuit, and the control circuit controls the feedback current output by the output circuit to keep zero magnetic flux in the magnetism collecting ring 211; and then the magnitude of the current to be measured can be calculated according to the voltage value of the sampling resistor connected in series in the feedback circuit.
The transient current measurement system 1 comprises an electromagnetic shielding shell 113 and a measurement device 20; the electromagnetic shielding shell 113 is enclosed to form a containing cavity 1121, the measuring device 20 is contained in the containing cavity 1121, and the electromagnetic shielding shell 113 is used for inhibiting external electromagnetic interference; the measuring device 20 comprises a TMR current sensor 21, a feedback component 22, a signal processing circuit 23 and a PCB 24, wherein the TMR current sensor 21, the feedback component 22 and the signal processing circuit 23 are all arranged on the PCB 24, the TMR current sensor 21 is electrically connected with the feedback component 22, and the feedback component 22 is electrically connected with the signal processing circuit 23; the TMR current sensor 21 is configured to convert a magnetic field difference value generated by the current to be measured and the feedback current into a voltage signal for outputting, and the output voltage signal controls the feedback component 22; the feedback assembly 22 is used to implement closed loop control; the signal processing circuit 23 is configured to filter and amplify the voltage signal output by the feedback component 22, and then convert the voltage signal into a digital signal for output; by providing electromagnetic shield case 113, thereby, the shielding effectiveness of TMR current sensor 21 is improved, and the measurement range of TMR current sensor 21 is increased; at the same time, the measurement accuracy of TMR current sensor 21 is improved.
It should be noted that in this document relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
Finally, it should be noted that: it is apparent that the above examples are only illustrative of the present invention and are not limiting of the embodiments. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. And obvious variations or modifications thereof are contemplated as falling within the scope of the present invention.
Claims (10)
1. A measurement system for transient current, characterized by: comprises an electromagnetic shielding shell and a measuring device;
the electromagnetic shielding shell is enclosed to form a containing cavity, the measuring device is contained in the containing cavity, and the electromagnetic shielding shell is used for inhibiting external electromagnetic interference;
the measuring device comprises a TMR current sensor, a feedback assembly, a signal processing circuit and a PCB board, wherein the TMR current sensor, the feedback assembly and the signal processing circuit are all arranged on the PCB board, the TMR current sensor is electrically connected with the feedback assembly, and the feedback assembly is electrically connected with the signal processing circuit;
the TMR current sensor is used for converting a magnetic field difference value generated by the current to be detected and the feedback current into a voltage signal to be output, and the output voltage signal controls the feedback component;
the feedback component is used for realizing closed-loop control;
the signal processing circuit is used for converting the voltage signal output by the feedback component into a digital signal for output after filtering and amplifying.
2. The transient current measurement system according to claim 1, wherein: the PCB comprises a round part and a rectangular part, wherein an arc-shaped groove matched with the round part is formed in one end of the rectangular part, the bottom end of the round part is inserted into the arc-shaped groove, and the outer peripheral wall of the round part is connected with the inner peripheral wall of the arc-shaped groove.
3. The transient current measurement system according to claim 2, wherein: the TMR current sensor comprises a magnetic focusing ring and 2n TMR chips, wherein n is a natural number greater than or equal to 1, and the magnetic focusing ring and the 2n TMR chips are arranged on one side of the circular part.
4. The measurement system for transient current according to claim 3, wherein: the magnetic focusing ring comprises 2n arc plates, wherein n is a natural number greater than or equal to 1, the 2n arc plates are arranged around the circumference of the circular part at intervals, a gap is formed between every two adjacent arc plates, the 2n arc plates form 2n gaps, the TMR chips are arranged in one-to-one correspondence with the gaps, and the 2n TMR chips are respectively arranged in the 2n gaps.
5. The measurement system for transient current according to any one of claims 3 to 4, wherein: the feedback assembly comprises a feedback winding, a control circuit, an output circuit and a sampling resistor, wherein the feedback winding is wound on the round part and the magnetic focusing ring, and the control circuit, the output circuit and the sampling resistor are integrated on the rectangular part;
the control circuit is coupled between the TMR chip and the output circuit, the output circuit is connected with the feedback winding, the feedback winding is connected with the sampling resistor, and the sampling resistor is connected with the signal processing circuit.
6. The transient current measurement system according to claim 1, wherein: the electromagnetic shielding shell comprises a body and a cover plate, an opening is formed in the bottom end of the body, the body is enclosed to form the accommodating cavity, the opening is communicated with the accommodating cavity, and the cover plate is covered at the opening so that the accommodating cavity is closed.
7. The transient current measurement system according to claim 6, wherein: the body includes shell and inner shell, the shell encloses to establish into the cavity, the inner shell encloses to establish the chamber holds, the inner shell inserts and locates in the cavity, the outer wall of inner shell with the inner wall laminating of cavity.
8. The transient current measurement system according to claim 7, wherein: the inner shell comprises a first shell and a second shell, one side of the first shell is buckled on the second shell, and the first shell and the second shell jointly enclose the accommodating cavity;
the bottom of first casing has seted up first logical groove, the bottom of second casing seted up with first logical groove looks adaptation's second logical groove, first logical groove with the second logical groove corresponds the setting, first logical groove with the second logical groove constitutes jointly the opening.
9. The transient current measurement system according to claim 8, wherein: the first casing towards one side of second casing is provided with the arch, the second casing towards one side of first casing seted up with protruding looks adaptation draw-in groove, protruding inserting is located the draw-in groove, so that first casing with the second casing is connected.
10. The transient current measurement system according to claim 7, wherein: the outer shell is made of high-conductivity materials, and the inner shell is made of high-permeability materials.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211688568.8A CN116338276A (en) | 2022-12-27 | 2022-12-27 | Measurement system for transient current |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211688568.8A CN116338276A (en) | 2022-12-27 | 2022-12-27 | Measurement system for transient current |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116338276A true CN116338276A (en) | 2023-06-27 |
Family
ID=86893649
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211688568.8A Pending CN116338276A (en) | 2022-12-27 | 2022-12-27 | Measurement system for transient current |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116338276A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117269559A (en) * | 2023-10-13 | 2023-12-22 | 珠海多创科技有限公司 | Current sensing device, metering equipment and on-line monitoring equipment |
-
2022
- 2022-12-27 CN CN202211688568.8A patent/CN116338276A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117269559A (en) * | 2023-10-13 | 2023-12-22 | 珠海多创科技有限公司 | Current sensing device, metering equipment and on-line monitoring equipment |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Ziegler et al. | Current sensing techniques: A review | |
| KR100211395B1 (en) | Dc current sensor | |
| JP4835868B2 (en) | Current sensor | |
| EP2622690B1 (en) | Battery current sensor | |
| EP0356171A2 (en) | Direct-coupled fluxgate current sensor and sensing method using the same | |
| CN107462758B (en) | Closed loop current sensor | |
| JP4788922B2 (en) | Current sensor | |
| JP2010071822A (en) | Current sensor | |
| CN116338276A (en) | Measurement system for transient current | |
| JP2007113965A (en) | Current sensor | |
| WO1995020167A1 (en) | Current sensor including magnetic sensors | |
| JP2008215970A (en) | Bus bar integrated current sensor | |
| CN102004203A (en) | Leakage current detection device | |
| EP1340092B1 (en) | Current sensor | |
| CN100365419C (en) | Non-contact measuring system for direct current | |
| EP2680013B1 (en) | Electrical current transducer | |
| US9547026B1 (en) | Plug-through energy monitor | |
| CA2326798A1 (en) | Current transformer and method for correcting asymmetries therein | |
| GB2438057A (en) | Magnetic sensor with electromagnetic radiation compensation | |
| US20230204686A1 (en) | Magnetic field detection device and magnetic field detection device array | |
| CN113791263B (en) | Current detection device and electronic equipment | |
| CN115524520A (en) | Magnetic shield device and current sensor | |
| CN210835038U (en) | Anti-external magnetic open-loop current sensor | |
| WO2014005431A1 (en) | Chip-type magnetic sensor | |
| JP2005055326A (en) | Conductor current measurement method and magnetic field sensor for measuring conductor current |
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 |