CN212932753U - Current sensor - Google Patents

Abstract

The utility model provides a current sensor, it detects according to the magnetic induction that is measured the electric current and produces measured the electric current, it includes: a current-carrying conductor for providing a flow path for the current to be measured, the current-carrying conductor comprising a first leg, a second leg, and a connection between the first and second legs; a first magnetic sensor comprising a first magnetic sensor cell and a second magnetic sensor cell, the first and second magnetic sensor cells being located above and below the first leg, respectively, to form a differential output. Compared with the prior art, the utility model discloses can promote current sensor detection precision under inhomogeneous external magnetic field environment.

Description

Current sensor

[ technical field ] A method for producing a semiconductor device

The utility model relates to a current sensor technical field especially relates to a can promote current sensor that external magnetic field restraines.

[ background of the invention ]

Current sensors for measuring the magnitude of current are widely used in various electronic devices. In the current sensor in the prior art, a U-shaped conductor is integrated inside the current sensor, two magneto-resistance sensor units are arranged around the conductor, so that a current to be measured flows through the U-shaped conductor integrated inside the current sensor, and the two magneto-resistance sensor units perform differential measurement on a magnetic field generated by the current in the conductor, thereby achieving the purpose of detecting (or detecting) the current to be measured.

However, in the conventional current sensor, the distance between the two magnetoresistive sensor units above or below the U-shaped conductor is relatively long, and the current sensor has a weak ability to suppress an external magnetic field in an inhomogeneous external magnetic field environment, thereby reducing the detection accuracy.

Therefore, it is necessary to provide a technical solution to overcome the above problems.

[ Utility model ] content

An object of the utility model is to provide a current sensor, it can promote current sensor detection precision under inhomogeneous external magnetic field environment.

According to an aspect of the present invention, the present invention provides a current sensor, which detects a measured current according to a magnetic induction intensity generated by the measured current, including: a current-carrying conductor for providing a flow path for the current to be measured, the current-carrying conductor comprising a first leg, a second leg, and a connection between the first and second legs; a first magnetic sensor comprising a first magnetic sensor cell and a second magnetic sensor cell, the first and second magnetic sensor cells being located above and below the first leg, respectively, to form a differential output.

Further, the current sensor further includes a second magnetic sensor including a third magnetic sensor unit and a fourth magnetic sensor unit, the third magnetic sensor unit and the fourth magnetic sensor unit being respectively located below and above the second leg to form a differential output.

Further, the first magnetic sensor unit and the second magnetic sensor unit are oppositely arranged; the third magnetic sensor unit and the fourth magnetic sensor unit are disposed opposite to each other.

Further, the first magnetic sensor and the second magnetic sensor are both magneto-resistance sensors.

Further, the current sensor may further include a signal processing circuit that averages the differential output of the first magnetic sensor and the differential output of the second magnetic sensor.

Further, the first leg portion and the second leg portion are located on the same side of the connecting portion; one end of the first leg portion serves as one end of the current-carrying conductor, and the other end of the first leg portion is connected with one end of the connecting portion; one end of the second leg portion serves as the other end of the current-carrying conductor, and the other end of the second leg portion is connected with the other end of the connecting portion.

Compared with the prior art, the utility model discloses a current sensor includes current-carrying conductor and magnetic sensor, it includes first magnetic sensor unit and second magnetic sensor unit, first magnetic sensor unit with second magnetic sensor unit is located respectively the top and the below of first shank or second shank to form differential output. Thus, the utility model discloses can promote current sensor detection precision under inhomogeneous external magnetic field environment.

[ description of the drawings ]

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without inventive labor. Wherein:

fig. 1 is a schematic structural diagram of a current sensor according to an embodiment of the present invention;

FIG. 2 is a schematic sectional view taken along line A-A of FIG. 1;

fig. 3 is a schematic structural diagram of a current sensor according to another embodiment of the present invention;

fig. 4 is a schematic sectional view taken along line B-B of fig. 3.

[ detailed description ] embodiments

In order to make the above objects, features and advantages of the present invention more comprehensible, the present invention is described in detail with reference to the accompanying drawings and the detailed description.

Reference herein to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with at least one implementation of the invention is included. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Unless otherwise specified, the terms connected, and connected as used herein mean electrically connected, directly or indirectly.

Please refer to fig. 1, which is a schematic structural diagram of a current sensor according to an embodiment of the present invention. The current sensor shown in fig. 1 comprises a current carrying conductor 101 and a first magnetic sensor 102.

The current-carrying conductor 101 is used for providing a flow channel for a current I to be measured, so that the current I to be measured can flow through the current-carrying conductor 101. The current carrying conductor 101 includes a first leg portion 101a, a second leg portion 101b, and a connecting portion 101c between the first leg portion 101a and the second leg portion 101 b.

In the embodiment shown in fig. 1, the current carrying conductor 101 is a U-shaped conductor, wherein the first leg portion 101a and the second leg portion 101b are located on the same side of the connecting portion 101 c; one end of the first leg portion 101a serves as one end of the U-shaped conductor 101, and the other end of the first leg portion 101a is connected to one end of the connecting portion 101 c; one end of the second leg portion 101b serves as the other end of the U-shaped conductor 101, and the other end of the second leg portion 101b is connected to the other end of the connecting portion 101 c.

The current I to be measured flows in from one end of the first leg 101a, sequentially flows through the first leg 101a, the connecting portion 101c, and the second leg 101b, and flows out from one end of the second leg 101 b.

The first magnetic sensor 102 is located around the current-carrying conductor 101, and detects the measured current I from a magnetic field (or magnetic induction) generated by the current in the current-carrying conductor 101.

Please refer to fig. 2, which is a cross-sectional view along line a-a of fig. 1. In the embodiment shown in fig. 1 and 2, the first magnetic sensor 102 is a magnetoresistive sensor including a first magnetoresistive sensor cell 102a and a second magnetoresistive sensor cell 102 b. The first magnetoresistive sensor cell 102a is positioned above the first leg 101a, and the second magnetoresistive sensor cell 102b is positioned below the first leg 101 a; the first magnetoresistive sensor cell 102a and the second magnetoresistive sensor cell 102b are oppositely arranged; the distance between the first magnetoresistive sensor cell 102a and the second magnetoresistive sensor cell 102b is very close.

The current I in the current carrying conductor 101 generates a magnetic field H at the first magnetoresistive sensor cell 102a₁₁A magnetic field-H is generated at the second magnetoresistive sensor cell 102b₁₂. The output of the first magnetoresistive sensor cell 102a is V₁₁＝S[(H₁₁/I)I+H₀]Where S is the sensitivity of the magnetoresistive sensor cell with respect to the magnetic field, H₀An external magnetic field; the output of the second magnetoresistive sensor cell 102b is V₁₂＝S[-(H₁₂/I)I+H₀](ii) a The output of the first magnetic sensor 102 is V₁＝V₁₁-V₁₂＝S[(H₁₁+H₁₂)/I]I. Because the distance between the first magnetoresistive sensor unit 102a and the second magnetoresistive sensor unit 102b is very close, the current sensor has very strong inhibition capability to the non-uniform external magnetic field, and the detection accuracy of the current sensor in the non-uniform external magnetic field environment is improved.

Since the first leg 101a and the second leg 101b are opposite to each other, in another implementation, the first magnetoresistive sensor unit 102a may be located above the second leg 101b, and the second magnetoresistive sensor unit 102b may be located below the second leg 101b to form a differential output, which is not described herein again.

Please refer to fig. 3, which is a schematic structural diagram of a current sensor according to another embodiment of the present invention. The current sensor shown in fig. 3 includes a current carrying conductor 201, a first magnetic sensor 202, and a second magnetic sensor 203. Fig. 3 differs from fig. 1 in that fig. 3 adds a second magnetic sensor 203 to the current sensor shown in fig. 1.

The current carrying conductor 201 is used for providing a flow channel for a measured current I, so that the measured current I can flow through the current carrying conductor 201. The current carrying conductor 201 includes a first leg 201a, a second leg 201b, and a connection portion 201c between the first and second legs 201a, 201 b.

In the embodiment shown in fig. 3, the current carrying conductor 201 is a U-shaped conductor, wherein the first leg portion 201a and the second leg portion 201b are located on the same side of the connecting portion 201 c; one end of the first leg portion 201a serves as one end of the U-shaped conductor 201, and the other end of the first leg portion 201a is connected to one end of the connecting portion 201 c; one end of the second leg portion 201b serves as the other end of the U-shaped conductor 201, and the other end of the second leg portion 201b is connected to the other end of the connecting portion 201 c.

The current I to be measured flows in from one end of the first leg 201a, sequentially flows through the first leg 201a, the connecting portion 201c, and the second leg 201b, and flows out from one end of the second leg 201 b.

The first and second magnetic sensors 202 and 203 are located around the current carrying conductor 201 and detect the measured current I from a magnetic field (or magnetic induction) generated by the current in the current carrying conductor 201.

Please refer to fig. 4, which is a cross-sectional view along line B-B of fig. 3. In the embodiment shown in fig. 3 and 4, the first magnetic sensor 202 and the second magnetic sensor 203 are each a magnetoresistive sensor, and the first magnetic sensor 202 includes a first magnetoresistive sensor cell 202a and a second magnetoresistive sensor cell 202 b. The first magnetoresistive sensor unit 202a is positioned above the first leg 201a, and the second magnetoresistive sensor unit 202b is positioned below the first leg 201 a; the first magnetoresistive sensor cell 202a and the second magnetoresistive sensor cell 202b are disposed oppositely; the distance between the first magnetoresistive sensor cell 202a and the second magnetoresistive sensor cell 202b is very close. The second magnetic sensor 203 includes a third magnetoresistive sensor cell 203a and a fourth magnetoresistive sensor cell 203 b. The third magnetoresistive sensor unit 203a is positioned below the second leg 201b, and the fourth magnetoresistive sensor unit 203b is positioned above the second leg 201 b; the third magnetoresistive sensor cell 203a and the fourth magnetoresistive sensor cell 203b are oppositely disposed; the distance between the third magnetoresistive sensor cell 203a and the fourth magnetoresistive sensor cell 203b is very close.

The current I in the current carrying conductor 201 generates a magnetic field H at the first magnetoresistive sensor cell 202a₁₁A magnetic field-H is generated at the second magnetoresistive sensor cell 202b₁₂A magnetic field H is generated at the third magnetoresistive sensor cell 203a₂₁A magnetic field-H is generated at the fourth magnetoresistive sensor cell 203b₂₂. The output of the first magnetoresistive sensor cell 202a is V₁₁＝S[(H₁₁/I)I+H₀]Where S is the sensitivity of the magnetoresistive sensor cell with respect to the magnetic field, H₀An external magnetic field; the output of the second magnetoresistive sensor cell 202b is V₁₂＝S[-(H₁₂/I)I+H₀](ii) a The output of the first magnetic sensor 202 is V₁＝V₁₁-V₁₂＝S[(H₁₁+H₁₂)/I]I. The output of the third magnetoresistive sensor unit 203a is V₂₁＝S[(H₂₁/I)I+H₀]Where S is the sensitivity of the magnetoresistive sensor cell with respect to the magnetic field, H₀An external magnetic field; the output of the fourth magnetoresistive sensor unit 203b is V₂₂＝S[-(H₂₂/I)I+H₀](ii) a The output of the second magnetic sensor 203 is V₂＝V₂₁-V₂₂＝S[(H₂₁+H₂₂)/I]I. The average value of the outputs of the first and second magnetic sensors 202 and 203 is V ═ V (V ═ V)₁+V₂)/2. In one embodiment, the differential output of the first magnetic sensor and the differential output of the second magnetic sensor are averaged by a signal processing circuit (not shown), i.e., V ═ V (V ═ V-₁+V₂)/2。

Because the distance between the first magnetoresistive sensor unit 202a and the second magnetoresistive sensor unit 202b is very close, and the distance between the third magnetoresistive sensor unit 203a and the fourth magnetoresistive sensor unit 203b is very close, the current sensor has very strong inhibition capability to the non-uniform external magnetic field, and the detection accuracy of the current sensor in the non-uniform external magnetic field environment is improved.

The "U-shaped" herein refers to a shape similar to U in a broad sense, and does not need to be strictly consistent with the shape of the letter U, and certain modifications can be made. That is, the U-shaped conductors 101, 201 in fig. 1 and 3 may be standard U-shaped conductors or U-like shaped conductors.

In the present invention, the terms "connected", "connecting", and the like denote electrical connections, and, unless otherwise specified, may denote direct or indirect electrical connections.

The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiment, but all equivalent modifications or changes made by those skilled in the art according to the present invention should be included in the protection scope of the claims.

Claims (6)

1. A current sensor for detecting a current to be measured based on magnetic induction generated by the current to be measured, comprising:

a current-carrying conductor for providing a flow path for the current to be measured, the current-carrying conductor comprising a first leg, a second leg, and a connection between the first and second legs;

a first magnetic sensor comprising a first magnetic sensor cell and a second magnetic sensor cell, the first and second magnetic sensor cells being located above and below the first leg, respectively, to form a differential output.

2. The current sensor of claim 1, further comprising a second magnetic sensor,

the second magnetic sensor includes a third magnetic sensor cell and a fourth magnetic sensor cell,

the third and fourth magnetic sensor units are located below and above the second leg, respectively, to form a differential output.

3. The current sensor of claim 2,

the first magnetic sensor unit and the second magnetic sensor unit are arranged oppositely;

the third magnetic sensor unit and the fourth magnetic sensor unit are disposed opposite to each other.

4. The current sensor of claim 2,

the first magnetic sensor and the second magnetic sensor are both magneto-resistance sensors.

5. The current sensor of claim 2, further comprising a signal processing circuit,

the signal processing circuit averages the differential output of the first magnetic sensor and the differential output of the second magnetic sensor.

6. The current sensor of claim 1,

the first leg and the second leg are located on the same side of the connecting portion;

one end of the first leg portion serves as one end of the current-carrying conductor, and the other end of the first leg portion is connected with one end of the connecting portion;

one end of the second leg portion serves as the other end of the current-carrying conductor, and the other end of the second leg portion is connected with the other end of the connecting portion.

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