CN217060327U

CN217060327U - Micro current detector for magnetic ring coil

Info

Publication number: CN217060327U
Application number: CN202122695383.7U
Authority: CN
Inventors: 沈洁; 方建明; 冯文龙
Original assignee: GUANGZHOU SINO-AUTO TECHNOLOGY CO LTD
Current assignee: GUANGZHOU SINO-AUTO TECHNOLOGY CO LTD
Priority date: 2021-11-04
Filing date: 2021-11-04
Publication date: 2022-07-26
Anticipated expiration: 2031-11-04

Abstract

The utility model provides a magnetic ring coil micro current detector, which comprises a magnetic ring coil and a detection circuit, wherein the magnetic ring coil is connected with the detection circuit; the magnetic ring coil comprises a magnetic ring and a secondary winding, the secondary winding is wound on the magnetic ring, the detection circuit comprises a power supply circuit, an oscillation circuit, a sampling circuit, a filtering amplification circuit and a signal processing circuit, the input end of the power supply circuit is connected with the input and output interface of the power supply, the output end of the power supply circuit is respectively connected with the oscillation circuit, the signal processing circuit and the filtering amplification circuit, the oscillation circuit is connected with the magnetic ring coil, the sampling circuit, the first filtering amplification circuit and the signal processing circuit are sequentially connected, and the output end of the signal processing circuit is connected with the input and output interface of the power supply. The utility model has the advantages of simple structure, stable operation, low power consumption, high precision of micro current detection and suitability for both AC and DC.

Description

Magnetic ring coil micro current detector

Technical Field

The utility model relates to the field of electronic technology, especially, relate to a little current detection ware of magnetic ring coil.

Background

In engineering measurement, alternating current can be conveniently measured in a non-contact manner through a current transformer, the principle of the alternating current is the electromagnetic induction principle discovered by michael · faraday in 1831, but direct current, especially tiny direct current, is often not easy to be accurately measured in a non-contact state.

In the pipe for conveying the explosive medium, static electricity is generated due to friction during conveying, part of the static electricity is led to the ground through the metal pipe, and if the static electricity is too much, static electricity discharge can be caused in the process, and then explosion can be caused. If the micro current on the pipeline can be measured, the early warning and the accident prevention can be realized.

In the process of pneumatic conveying or gravity conveying, materials are charged with static electricity due to friction between the materials, the materials and pipelines, the materials and conveying media and the pipelines. If the charge amount between the charged material and the metal objects such as pipelines and bins exceeds a critical value under the condition of explosive dust or gas, electrostatic discharge is caused, and then explosion may be caused. If the micro current on the pipeline can be measured, the electrification condition of the material can be calculated, so that the early warning and the accident prevention can be realized.

In production and research, the combined current of a plurality of wires needs to be measured many times, so that the working state of the system is judged or the leakage current is measured, if the micro current on the pipeline can be measured, the electrification condition of the material can be calculated, and the occurrence of accidents is pre-warned and prevented.

With the demand increasing, the traditional ferrite materials have been unable to meet the demand in many occasions. The nanocrystalline magnetic ring made of the novel material is widely applied to the fields of household air conditioners, rail transit, solar energy, wind energy power generation and the like. Most of the nanocrystalline magnetic rings on the market are made of iron-based nanocrystalline soft magnetic alloy. It has good high-frequency characteristics, lower coercive force and loss. The manufacturing process is that five elements of iron, silicon, boron, copper and niobium are mixed and heated to 1400 ℃ according to a fixed proportion and then are rapidly cooled to manufacture the belt-shaped material. And then wound into a circular core. Then heat treatment is carried out to make the magnetic material crystallize again, thus having good soft magnetic performance.

SUMMERY OF THE UTILITY MODEL

The utility model provides a magnetic ring coil micro current detector, which comprises a magnetic ring coil and a detection circuit, wherein the magnetic ring coil is connected with the detection circuit; the magnetic ring coil comprises a magnetic ring and a secondary winding, the secondary winding is wound on the magnetic ring, the detection circuit comprises a power circuit, an oscillation circuit, a sampling circuit, a first filtering and amplifying circuit and a signal processing circuit, the input end of the power circuit is connected with an input and output interface of a power supply, the output end of the power circuit is respectively connected with the oscillation circuit, the signal processing circuit and the first filtering and amplifying circuit, the oscillation circuit is connected with the magnetic ring coil, the sampling circuit, the first filtering and amplifying circuit and the signal processing circuit are sequentially connected, and the output end of the signal processing circuit is connected with the input and output interface of the power supply.

As a further improvement of the present invention, the magnetic ring coil includes a feedback winding wound on the magnetic ring.

As a further improvement, the small current detector of this magnetic ring coil includes the on-the-spot zero setting circuit, the on-the-spot zero setting circuit with signal processing circuit links to each other.

As a further improvement, the small current detector of this magnetic ring coil includes on-the-spot calibration circuit, on-the-spot calibration circuit with signal processing circuit links to each other.

As a further improvement, the utility model discloses a little current detection ware of this magnetic ring coil includes frequency conversion circuit, second filter amplifier circuit, the magnetic ring coil with frequency conversion circuit links to each other, frequency conversion circuit with second filter amplifier circuit links to each other, second filter amplifier circuit with signal processing circuit links to each other, power supply circuit does frequency conversion circuit second filter amplifier circuit provides the power.

As a further improvement of the present invention, the magnetic ring is made of a material having a low coercive force and a high magnetic permeability.

As a further improvement of the utility model, the magnetic ring is made of permalloy or amorphous and nanocrystalline materials.

As a further improvement of the present invention, the number of the feedback windings is one or more.

As a further improvement of the present invention, the first filtering and amplifying circuit is connected to the magnetic ring coil through the feedback winding.

The utility model has the advantages that: 1. the structure is simple, the work is stable, the power consumption is low, the detection precision of the micro current is high, and the device is suitable for both alternating current and direct current; 2. the device has no contact with a primary wire to be measured, can measure various currents such as the current of a common wire, the combined current of a plurality of wires in a wire tube, the current generated by the movement of charged particles in a pipeline, the leakage current of the pipeline and the like, and has wide application; 3. zero setting and calibration can be carried out on site, and fixed interference on site is eliminated; 4. a feedback winding can be added to improve the measurement precision; 5. frequency auxiliary measurement can be added to improve the measurement effect.

Drawings

Fig. 1 is a schematic block diagram of the magnetic ring coil micro current detector of the present invention.

Detailed Description

The utility model discloses a small current detector of magnetic ring coil, including magnetic ring coil 1, detection circuitry, magnetic ring coil 1 with detection circuitry links to each other.

As shown in fig. 1, the magnetic loop coil 1 includes a magnetic loop and a secondary winding, and the secondary winding is wound on the magnetic loop. The detection circuit comprises a power supply circuit 20, an oscillation circuit 21, a sampling circuit 22, a first filtering and amplifying circuit 23 and a signal processing circuit 24, wherein the input end of the power supply circuit 20 is connected with an input/output interface 3 of a power supply, the output end of the power supply circuit 20 is respectively connected with the oscillation circuit 21, the signal processing circuit 24 and the first filtering and amplifying circuit 23, the oscillation circuit 21 is connected with the magnetic ring coil 1, the sampling circuit 22, the first filtering and amplifying circuit 23 and the signal processing circuit 24 are sequentially connected, and the output end of the signal processing circuit 24 is connected with the input/output interface 3 of the power supply.

Power is introduced into the system through the input output interface 29 and adapted by the power circuit 20. The oscillating circuit 21 generates a suitable waveform, and is connected to the secondary winding of the magnetic ring coil 1, and under the excitation of the signal, the magnetic ring repeatedly enters a magnetic saturation state. When no current flows through the primary line, the waveform is symmetrical up and down; when current passes through the primary wire, a magnetic field is generated around the primary wire, the magnetic field changes the saturation point of the magnetic ring, the waveform of the magnetic field deviates, the offset is obtained by the sampling circuit 22, and then the signal linearly related to the current of the primary wire can be obtained by amplifying the offset by the filtering wave amplifying circuit 23.

The magnetic ring coil 1 comprises a feedback winding, and the feedback winding is wound on the magnetic ring. One or more feedback windings may be provided, and the primary wire to be measured passes through the middle of the magnetic loop coil 1. For more accurate measurement, a feedback winding can be added in the magnetic loop coil 1, an output point is reversely led into the feedback winding, a magnetic field opposite to a magnetic field formed by primary line current can be formed on the feedback winding, the two magnetic fields are mutually offset when being exactly equal, the output is zero, namely, negative feedback is led into the magnetic loop coil 1, and the measurement precision and stability can be improved.

The first filtering and amplifying circuit 23 is connected with the magnetic loop coil 1 through the feedback winding. The signal from the first filtering and amplifying circuit 23 can form negative feedback to the magnetic loop coil 1 through the feedback winding, and the detection precision can be improved by using a negative feedback mechanism.

The magnetic loop coil micro current detector comprises a field zero setting circuit 25, and the field zero setting circuit 25 is connected with the signal processing circuit 24.

The magnetic loop coil micro current detector comprises a field calibration circuit 26, and the field calibration circuit 26 is connected with the signal processing circuit 24.

The magnetic loop coil micro current detector is provided with a field zero setting circuit 25 and a field calibration circuit 26, and zero setting and calibration can be carried out after the magnetic loop coil micro current detector is installed so as to eliminate field interference.

The magnetic loop coil micro current detector comprises a frequency conversion circuit 27 and a second filtering and amplifying circuit 28, wherein the magnetic loop coil is connected with the frequency conversion circuit 27, the frequency conversion circuit 27 is connected with the second filtering and amplifying circuit 28, the second filtering and amplifying circuit 28 is connected with the signal processing circuit 24, and the power supply circuit 20 supplies power to the frequency conversion circuit 27, the oscillating circuit 21, the signal processing circuit 24, the first filtering and amplifying circuit 23 and the second filtering and amplifying circuit 28. Besides affecting the saturation point of the magnetic loop coil 1, the primary line current magnetic field also causes the frequency of the oscillating circuit 21 to change slightly, so that a frequency conversion circuit 27 can be introduced, and the frequency is filtered and amplified by a second filter circuit 28 and then introduced into a signal processing circuit 24 for auxiliary measurement.

The utility model discloses a key point:

1. the magnetic loop coil is composed of a magnetic loop and a secondary winding, one or more feedback windings can be arranged, and a primary wire to be measured passes through the middle of the magnetic loop coil 1.

2. The magnetic ring of the magnetic ring coil 1 uses low coercive force and high magnetic permeability materials, including but not limited to permalloy, amorphous and nanocrystalline materials.

3. The utility model discloses utilize specific magnetic field to measure the influence of the magnetic saturation point of coil.

4. The utility model discloses zero set and calibration device with can adjust many times supply zero set and calibration to use to offset the detection site environmental disturbance.

5. The utility model discloses can set up frequency auxiliary measuring circuit, improve the testing performance.

6. The utility model discloses can set up the feedback winding and form negative feedback closed loop at magnetic ring coil 1 and measure, measurement accuracy is high.

7. The object of measurement (primary wire) is an object capable of forming directional moving charges, including but not limited to conductors, metal conveying pipes, non-metal conveying pipes, wire harnesses.

The foregoing is a more detailed description of the present invention, taken in conjunction with the specific preferred embodiments thereof, and it is not intended that the invention be limited to the specific embodiments shown and described. To the utility model belongs to the technical field of ordinary technical personnel, do not deviate from the utility model discloses under the prerequisite of design, can also make a plurality of simple deductions or replacement, all should regard as belonging to the utility model discloses a protection scope.

Claims

1. A magnetic loop coil micro current detector is characterized in that: the magnetic ring coil (1) is connected with the detection circuit; the magnetic ring coil (1) comprises a magnetic ring and a secondary winding, the secondary winding is wound on the magnetic ring, the detection circuit comprises a power supply circuit (20), an oscillation circuit (21), a sampling circuit (22), a first filtering amplification circuit (23) and a signal processing circuit (24), the input end of the power circuit (20) is connected with the input/output interface (3) of the power supply, the output end of the power supply circuit (20) is respectively connected with the oscillating circuit (21), the signal processing circuit (24) and the first filtering and amplifying circuit (23), the oscillation circuit (21) is connected with the magnetic ring coil (1), the sampling circuit (22), the first filtering and amplifying circuit (23) and the signal processing circuit (24) are sequentially connected, the output end of the signal processing circuit (24) is connected with the input and output interface (3) of the power supply.

2. The magnetic loop coil micro current detector as claimed in claim 1, wherein: the magnetic ring coil (1) comprises a feedback winding, and the feedback winding is wound on the magnetic ring.

3. The magnetic loop coil micro current detector as claimed in claim 1, wherein: the magnetic loop coil micro-current detector comprises a field zero setting circuit (25), wherein the field zero setting circuit (25) is connected with the signal processing circuit (24).

4. The magnetic loop coil micro current detector as claimed in claim 1, wherein: the magnetic loop coil micro current detector comprises a field calibration circuit (26), and the field calibration circuit (26) is connected with the signal processing circuit (24).

5. The magnetic loop coil micro current detector as claimed in claim 1, wherein: the magnetic loop coil micro current detector comprises a frequency conversion circuit (27) and a second filtering and amplifying circuit (28), wherein the magnetic loop coil is connected with the frequency conversion circuit (27), the frequency conversion circuit (27) is connected with the second filtering and amplifying circuit (28), the second filtering and amplifying circuit (28) is connected with the signal processing circuit (24), and the power supply circuit (20) supplies power to the frequency conversion circuit (27) and the second filtering and amplifying circuit (28).

6. The magnetic loop coil micro current detector as claimed in claim 1, wherein: the magnetic ring is made of a material with low coercive force and high magnetic permeability.

7. The magnetic loop coil micro current detector as claimed in claim 6, wherein: the magnetic ring is made of permalloy, amorphous and nanocrystalline.

8. The magnetic loop coil micro current detector as claimed in claim 2, wherein: the number of the feedback windings is one or more.

9. The magnetic loop coil micro current detector as claimed in claim 2, wherein: the first filtering and amplifying circuit (23) is connected with the magnetic loop coil (1) through the feedback winding.