CN114441823A - Hall sensor, current detection device and current detection method - Google Patents

Abstract

The application provides a Hall sensor, a current detection device and a current detection method, wherein the Hall sensor comprises a first magnetizer, a second magnetizer and a first end, wherein the first end and the second end opposite to the first end are included; the second magnetizer comprises a third end and a fourth end opposite to the third end; a first Hall element; and a second hall element; a first air gap is formed between the first end and the third end, a second air gap is formed between the second end and the fourth end, a measuring hole for a wire to be measured to pass through is formed between the first magnetizer and the second magnetizer, the first hall element is arranged in the first air gap, and the second hall element is arranged in the second air gap. The Hall sensor has small size and strong anti-interference capability.

Description

Hall sensor, current detection device and current detection method

technical field

This article relates to current detection technology, especially a Hall sensor, a current detection device and a current detection method.

Background technique

With the increasing requirements for the integration of electric vehicle power systems, as one of the core components of electric vehicle power, the power density requirements of inverters (motor controllers) are also getting higher and higher. As one of the important devices in the power circuit of the inverter, the design size and performance of the current sensor will also seriously restrict its further improvement of the power density.

At present, the Hall current sensors commonly used in the market have different installation methods due to different packaging methods, and the size is basically determined by the size of the magnetic core. In addition, most of the current Hall sensors used in mainstream applications are in the form of a single air gap single chip (Hall element), which are large in size and are susceptible to external magnetic field interference, such as magnetic field interference between three phases.

SUMMARY OF THE INVENTION

In order to solve the above technical problems, the present application provides a Hall sensor, which includes:

a first magnetic conductor, including a first end and a second end opposite to the first end;

the second magnetic conductor includes a third end and a fourth end opposite to the third end;

a first Hall element; and

the second Hall element;

Wherein, a first air gap is formed between the first end and the third end, a second air gap is formed between the second end and the fourth end, and the first magnetic conductor and the first A measurement hole for the wire to be tested to pass through is formed between the two magnetic conductors, the first Hall element is arranged in the first air gap, and the second Hall element is arranged in the second air gap.

In an exemplary embodiment, the first and second magnetic conductors are both bar-shaped.

In an exemplary embodiment, both the first magnetic conductor and the second magnetic conductor are arc-shaped structures;

The middle portions of the first magnet conductor and the second magnet conductor are arched in a direction away from each other.

In an exemplary embodiment, the first magnetic conductor and the second magnetic conductor are in plane symmetry.

In an exemplary embodiment, the Hall sensor further includes a housing, and an annular cavity is provided in the housing;

The first magnet conducting body, the second magnet conducting body, the first hall element and the second hall element are all arranged in the annular cavity.

In an exemplary embodiment, the housing includes a top cover and a bottom case;

the bottom case comprises a bottom plate provided with a first through hole and a plurality of side plates arranged on the edge of the bottom plate;

The top cover comprises a top plate provided with a second through hole and a cylinder connected to the top plate and coaxially arranged with the second through hole;

Wherein, one end of the cylinder extends into the first through hole of the bottom plate.

In an exemplary embodiment, a snap connection is formed between the casing and the bottom casing.

The present application also proposes a current detection device, which includes the above-mentioned Hall sensor.

In an exemplary embodiment, the first Hall element and the second Hall element output a voltage signal when the wire to be tested has a current passing through it;

The current detection device further includes a first calculation unit, the first calculation unit is electrically connected to the first Hall element and the second Hall element;

The first calculation unit calculates the current value of the current passing through the wire under test according to the following algorithm:

Among them, I _p is the current value of the current passing through the wire to be tested, V _out1 is the voltage value of the voltage signal output by the first Hall element, V _out2 is the voltage value of the voltage signal output by the second Hall element, and A ₀ is Conversion coefficient between magnetic field strength and voltage, γ is the conversion coefficient between current and magnetic field strength.

In an exemplary embodiment, the current detection device further includes a second calculation unit, and the second calculation unit includes an arithmetic circuit, a second analog-to-digital conversion module, and a second calculation module;

The arithmetic circuit is electrically connected to the first Hall element and the second Hall element, and the first Hall element and the second Hall element are directed to each other when a current flows through the wire to be tested. The operation circuit outputs a voltage signal, and the operation circuit is used for averaging the voltage signals output by the first Hall element and the second Hall element to obtain an average voltage signal;

The second analog-to-digital conversion module is used to convert the signal type of the average voltage signal from an analog signal to a digital signal;

Calculate the current value of the current through the wire under test according to the following algorithm:

Among them, I _p is the current value of the current passing through the wire under test, V is the voltage value of the average voltage signal, A ₀ is the conversion coefficient between magnetic field strength and voltage, and γ is the conversion coefficient between current and magnetic field strength.

The present application also proposes a current detection method, the detection method is implemented based on the above Hall sensor, and the detection method includes:

Obtain power supply sampling correction coefficient, zero-point voltage offset sampling coefficient and temperature drift correction coefficient;

Calculate the first current value of the current through the wire under test according to the following algorithm;

Among them, I ₀ is the first current value, V _out1 is the voltage value of the voltage signal output by the first Hall element, V _out2 is the voltage value of the voltage signal output by the second Hall element, and G is the sensitivity coefficient of the Hall sensor , T is the temperature drift correction coefficient, z is the zero-point voltage offset sampling coefficient, and p is the power supply sampling correction coefficient;

Obtain the software linear error correction coefficient, and calculate the current value of the wire under test according to the following algorithm:

I _p =l·I ₀

Wherein, I _p is the current value of the current passing through the wire under test, I ₀ is the first current value, and l is the software linearity error correction coefficient.

In the technical solution of the present application, since the first air gap and the second air gap are arranged between the first magnetic conductor and the second magnetic conductor, the total air gap length is increased, and increasing the air gap length can reduce the residual magnetic flux density , improve the magnetic saturation point of the magnet conductor, increase the utilization rate of the magnet conductor, and reduce the cross-sectional area of the magnet conductor under the condition of measuring the current of the same size, that is, reduce the size of the first magnet conductor and the second magnet conductor, and then The size of the entire Hall sensor can be reduced. Even if it is susceptible to external magnetic field interference due to increasing the length of the air gap, the interference can be removed by averaging the electrical signals output by the first Hall element and the second Hall element.

Other features and advantages of the present application will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the present application. Other advantages of the present application may be realized and attained by the approaches described in the specification and drawings.

Description of drawings

The accompanying drawings are used to provide an understanding of the technical solutions of the present application, and constitute a part of the specification. They are used to explain the technical solutions of the present application together with the embodiments of the present application, and do not constitute a limitation on the technical solutions of the present application.

1 is a schematic diagram of the internal structure of a Hall sensor according to an embodiment of the present invention;

Fig. 2 is the dismantling schematic diagram of a kind of Hall sensor in the embodiment of the present invention;

3 is a schematic perspective view of a Hall sensor in an embodiment of the present invention;

4 is a schematic top view of a Hall sensor in an embodiment of the present invention;

FIG. 5 is a half-section schematic diagram of a Hall sensor in an embodiment of the present invention;

6 is a schematic diagram of a connection of a current detection device in an embodiment of the present invention;

FIG. 7 is a schematic diagram of connection of a current detection device in an embodiment of the present invention.

Detailed ways

As described in FIG. 1 , FIG. 1 shows the structure of the Hall sensor 100 in this embodiment. The Hall sensor 100 includes a first magnetic conductor 1 , a second magnetic conductor 2 , a first Hall element 5 and a second Hall element 6 .

Both the first magnet conductor 1 and the second magnet conductor 2 are magnetic flux concentrators. The first magnet conductor 1 and the second magnet conductor 2 may be made of silicon steel sheets or pure iron sheet laminations, or may be made of ferrite magnetic materials. Both the first magnet conductor 1 and the second magnet conductor 2 may be configured in a bar shape.

The first magnetic conductor 1 includes a first end 11 and a second end 12 opposite to the first end 11 . The second magnetic conductor 2 includes a third end 21 and a fourth end 22 opposite to the third end 21 . The end of the first end 11 and the end of the third end 21 are disposed opposite and close to each other. The first end 11 and the third end 21 are spaced apart, and a first air gap 72 is formed between the first end 11 and the third end 21 . The end of the second end 12 and the end of the fourth end 22 are disposed opposite and close to each other. The second end 12 and the fourth end 22 are spaced apart, and a second air gap 73 is formed between the second end 12 and the fourth end 22 . The two ends of the first magnetic conductor 1 and the two ends of the second magnetic conductor 2 are respectively close to each other, and the first magnetic conductor 1 and the second magnetic conductor 2 can be enclosed to form a roughly annular structure. In this embodiment, the first magnetic conductor 1 and the second magnetic conductor 2 are both arc-shaped structures. The middle portions of the first magnet conductor 1 and the second magnet conductor 2 are arched in a direction away from each other. A measurement hole is formed between the middle part of the first magnetic conductor 1 and the middle part of the second magnetic conductor 2 for the wire to be tested to pass through. The wire to be tested can be the DC input end or the AC output end of the inverter connected to the vehicle.

The first Hall element 5 and the second Hall element 6 are disposed in the first air gap 72 and the second air gap 73, respectively. The first Hall element 5 and the second Hall element 6 may be of the same type of Hall element, and the Hall element is a magnetic sensor based on the Hall effect, and works by using the Hall effect. The Hall element includes a Hall plate, a power supply terminal and an output terminal. The Hall plate is a rectangular semiconductor single crystal thin sheet used to induce magnetic fields. Both the power terminal and the output terminal are electrically connected to the Hall plate. Hall plates are usually encapsulated in insulating housings. The power terminal is used for external DC power supply. The rated voltage of the Hall element can be 5V, and the DC power supply loads the voltage of 5V on the power terminal. The output terminal is used for outputting a voltage signal corresponding to the magnetic field strength of the electric field after the magnetic field is induced, and the voltage signal is usually an analog signal.

When the Hall sensor 100 is used to detect the current value passing through the wire to be tested, the wire to be tested is passed through the hole between the first magnetic conductor 1 and the second magnetic conductor 2, and the wire to be tested has the wire to be tested when the current passes through it. A magnetic field to be measured is formed around, and the magnetic field lines of the magnetic field to be measured are concentrated by the first magnetic conductor 1 and the second magnetic conductor 2, and the closed magnetic field lines are along the annular structure formed by the first magnetic conductor 1 and the second magnetic conductor 2 Extending, these magnetic induction lines also pass through the first Hall element 5 and the second Hall element 6 , and the magnetic induction intensity of the magnetic field to be measured detected by the first Hall element 5 and the second Hall element 6 is the same. When the outside of the Hall sensor 100 also has an interference magnetic field, the magnetic field lines of the interference magnetic field pass through the first Hall element 5 and the second Hall element 6 . One of the first Hall element 5 and the second Hall element 6 is penetrated by the magnetic field lines of the interfering magnetic field in the same direction and the magnetic field lines of the magnetic field to be measured, and is affected by the interfering magnetic field. The amplitude of the voltage signal output by the sensor 100 increases; the other Hall element in the first Hall element 5 and the second Hall element 6 is penetrated by the magnetic field lines of the interfering magnetic field in the opposite direction and the magnetic field lines of the magnetic field to be measured , under the influence of the interference magnetic field, the amplitude of the voltage signal output by the Hall sensor 100 decreases. The average voltage signal can be obtained by averaging the voltage signal output by the first Hall element 5 and the voltage signal output by the second Hall element 6 , and the average voltage signal is used as the output voltage signal of the Hall sensor 100 . The output voltage signal obtained by averaging the voltage signal output by the first Hall element 5 and the voltage signal output by the second Hall element 6 eliminates the influence of the interfering magnetic field, which makes the measurement accuracy of the Hall sensor 100 higher.

Specifically, take the scenario shown in Figure 1 as an example:

The first Hall element 5 is penetrated by the magnetic field lines of the interfering magnetic field and the magnetic field lines of the magnetic field to be measured in the same direction, and the voltage signal output by the first Hall element 5 is:

V _out1 =A ₀ ·(H _i +H ₀ )

Among them, V _out1 is the voltage value of the voltage signal output by the first Hall element 5, A ₀ is the conversion coefficient between voltage and magnetic field strength, A ₀ is determined by the characteristics of the Hall element, H _i is the magnetic field strength of the magnetic field to be measured, H is the magnetic field strength of the interfering magnetic field.

The second hall element 6 is penetrated by the magnetic field lines of the interfering magnetic field and the magnetic field lines of the magnetic field to be measured in the same direction, and the voltage signal output by the second hall element 6 is V _out2 :

V _out2 =A ₀ ·(H _i -H ₀ )

Among them, V _out2 is the voltage value of the voltage signal output by the second Hall element 6, A ₀ is the conversion coefficient between the magnetic field strength and the voltage, A ₀ is determined by the characteristics of the Hall element, and H _i is the magnetic field of the magnetic field to be measured. strength, H ₀ is the magnetic field strength of the interfering magnetic field.

The average voltage signal is:

Among them, V is the voltage value of the average voltage signal, A ₀ is the conversion coefficient between the magnetic field strength and voltage, A ₀ is determined by the characteristics of the Hall element, and H _i is the magnetic field strength of the magnetic field to be measured.

Therefore, the voltage value _V of the average voltage signal is only determined by the conversion coefficient A ₀ of the voltage and the magnetic field strength and the magnetic field strength Hi of the magnetic field to be measured, eliminating the influence of the disturbing magnetic field.

In this embodiment, since the first air gap 72 and the second air gap 73 are provided, the total air gap length is increased. Increasing the air gap length can reduce the residual magnetic flux density, increase the magnetic saturation point of the magnet conducting body, and increase the conducting Magnet utilization, in the case of measuring the current of the same size, the cross-sectional area of the magnetizer can be reduced, that is, the size of the first magnetizer 1 and the second magnetizer 2 can be reduced, thereby reducing the entire Hall sensor 100. size. Even if it is susceptible to external magnetic field interference due to increasing the length of the air gap, the interference can be removed by averaging the electrical signals output by the first Hall element 6 and the second Hall element 7 .

In an exemplary embodiment, the first magnet conductor 1 and the second magnet conductor 2 are in plane symmetry.

The first magnet conductor 1 and the second magnet conductor 2 are configured as plane-symmetric structures, and the first air gap 72 and the second air gap 73 are located on the symmetry plane between the first magnet conductor 1 and the second magnet conductor 2 , so that the anti-interference ability of the Hall sensor 100 can be further enhanced, and at the same time, the assembly is more convenient.

In an illustrative embodiment, the Hall sensor 100 also includes a housing 8 . The housing 8 is made of resin material. The housing 8 includes a bottom case 82 and a top cover 81 . The bottom case 82 includes a bottom plate 821 and a plurality of side plates 822 . Bottom plate 821 may be configured as a generally rectangular plate. The bottom plate 821 is provided with two straight holes 8211 and a first through hole 8212 . Both the straight hole 8211 and the first through hole 8212 penetrate through the bottom plate 821 . The two straight holes 8211 are parallel to each other. The two straight holes 8211 are respectively close to two opposite edges of the bottom plate 821 . The first through holes 8212 may be circular holes. The first through hole 8212 is disposed between the two straight holes 8211 and is located in the middle area of the bottom plate 821 . A plurality of side plates 822 are disposed on the edge of the bottom plate 821 and are perpendicular to the side plates 822 .

The top cover 81 includes a top plate 811 and a cylindrical body 812 . The top plate 811 is configured as a flat plate structure. A second through hole 8111 is provided in the middle of the top plate 811 . The second through holes 8111 may be circular holes. The axis of the cylindrical body 812 is perpendicular to the top plate 811 . One end of the cylinder body 812 is connected to the top plate 811 and is coaxial with the second through hole 8111 . The cylindrical body 812 is connected to the edge of the second through hole 8111 . The top plate 811 of the top cover 81 is covered with one end of the side plate 822 facing away from the bottom plate 821 . One end of the cylinder 812 facing away from the top plate 811 extends into the first through hole 8212 .

The top cover 81 and the bottom case 82 enclose an annular cavity, and the first magnetic conductor 1, the second magnetic conductor 2, the first Hall element 5 and the second Hall element 6 are all arranged in the annular cavity, and the shell The body 8 can protect the first magnetic conductor 1 , the second magnetic conductor 2 , the first Hall element 5 and the second Hall element 6 from damage.

In an exemplary embodiment, the Hall sensor 100 further includes a plurality of first connectors 5 and a plurality of second connectors 6 . The plurality of first connecting members 5 are all connected to the first magnetic conductor 1 and protrude from the casing 8 from a straight hole 8211 of the bottom plate 821 . The first connection member 5 and the first magnetic conductor 1 may be connected by welding. The plurality of second connecting members 6 are all connected to the second magnetic conductor 2 and protrude from the casing 8 from another straight hole 8211 of the bottom plate 821 . The second connecting member 6 and the second magnet conducting body 2 may be connected by welding.

The ends of the first connector 5 and the second connector 6 extending out of the housing 8 are both used for external mounting bases, and the mounting bases may be printed circuit boards. In this way, the Hall sensor 100 can be firmly fixed on the mounting base through the first connecting piece 5 and the second connecting piece 6 .

In an exemplary embodiment, a snap connection is adopted between the top cover 81 and the bottom case 82 . The top cover 81 also includes a plurality of female buckles 813 . A plurality of female buckles 813 may be respectively disposed on a plurality of corners of the top plate 811 .

The female buckle 813 includes a post 8131 and a positioning beam 8132 . Two pillars 8131 are provided. The pillars 8131 protrude from the top plate 811 toward the bottom plate 821 . The two pillars 8131 are arranged at intervals. Two ends of the positioning beam 8132 are respectively connected to one end of the two pillars 8131 facing away from the top plate 811 . The positioning beam 8132 is perpendicular to the pillar 8131.

The bottom case 82 also includes a plurality of buckles 822 . The number of the buckles 822 is the same as the number of the female buckles 813 . A plurality of clips 822 are respectively disposed on the intersection of the bottom plate 821 . The plurality of buckles 822 are respectively arranged in a one-to-one correspondence with the plurality of female buckles 813 . The buckle 822 includes an elastic part 8231 and a hook part 8232 . The elastic portion 8231 is configured in a strip shape and protrudes from the bottom plate 821 to the direction close to the top plate 811 . The hook portion 8232 is provided on the side surface of the elastic portion 8231 . The hook portion 8232 of the buckle 822 hooks the positioning beam 8132 of the female buckle 813 corresponding to the buckle 822 and is located between the two pillars 8131 of the female buckle 813 .

In this way, the plurality of snaps 822 respectively hook the plurality of female snaps 813, so that the top cover 81 and the bottom case 82 are connected by the snaps 822, which is more convenient for assembly.

This embodiment also provides a current detection device 1000 , and the current detection device 1000 includes the above-mentioned Hall sensor 100 and the first calculation unit 200 . The first calculation unit 200 includes a first analog-to-digital conversion module 201 and a first calculation module 202 . The first analog-to-digital conversion module 201 may be an analog-to-digital conversion circuit. The first computing module 202 may be a single chip computer or a computer.

The first analog-to-digital conversion module 201 is electrically connected to the first Hall element 5 and the second Hall element 6 of the Hall sensor 100 . The first hall element 5 and the second hall element 6 send the voltage signal with the analog signal as the carrier to the first analog-to-digital conversion module 201 . The first analog-to-digital conversion module 201 is electrically connected to the first calculation module 202, and is used to convert the signal type of the voltage signal sent by the first Hall element 5 and the second Hall element 6 from an analog signal to a digital signal and then send it to the digital signal. The first computing module 202 . The first calculation unit 200 calculates the current value on the wire under test according to the voltage signals sent by the first Hall element 5 and the second Hall element 6 .

The first calculation module 202 calculates the current value of the current passing through the wire under test according to the following algorithm:

Among them, I _p is the current value of the current passing through the wire to be tested, V _out1 is the voltage value of the voltage signal output by the first Hall element 5, V _out2 is the voltage value of the voltage signal output by the second Hall element 6, A ₀ is the conversion coefficient between magnetic field strength and voltage, and γ is the conversion coefficient between current and magnetic field strength.

The conversion coefficient A ₀ between the magnetic field strength and the voltage and the conversion coefficient between the current and the magnetic field strength are fixed values, which are determined by the characteristics of the Hall element.

This embodiment also provides another current detection device 2000 , and the current detection device 2000 includes the above-mentioned Hall sensor 100 and the second calculation unit 300 . The second computing unit 300 includes an arithmetic circuit 301 , a second analog-to-digital conversion module 302 and a second computing module 303 . The second analog-to-digital conversion module 302 may be an analog-to-digital conversion circuit. The second computing module 303 may be a single chip computer or a computer.

The arithmetic circuit 301 is electrically connected to the first Hall element 5 and the second Hall element 6 of the Hall sensor 100 . The first Hall element 5 and the second Hall element 6 send the voltage signal with the analog signal as the carrier to the arithmetic circuit 301, and the arithmetic circuit 301 obtains the voltage signal output by the first Hall element 5 and the second Hall element 6. The average voltage signal is obtained by averaging, and the average voltage signal is sent to the second analog-to-digital conversion module 302 . The second analog-to-digital conversion module 302 is electrically connected to the second calculation module 303 , and is used for converting the signal type of the average voltage signal from an analog signal to a digital signal and then sending it to the second calculation module 303 . The second calculation unit 300 calculates the current value on the wire under test according to the average voltage signal.

The second calculation module 303 calculates the current value of the current passing through the wire to be measured according to the following algorithm:

Among them, I _p is the current value of the current passing through the wire under test, V is the voltage value of the average voltage signal, A ₀ is the conversion coefficient between magnetic field strength and voltage, and γ is the conversion coefficient between current and magnetic field strength.

The conversion coefficient A ₀ between the magnetic field strength and the voltage and the conversion coefficient between the current and the magnetic field strength are fixed values, which are determined by the characteristics of the Hall element.

In an exemplary embodiment, this embodiment also proposes a current detection method, the detection method is implemented based on the above-mentioned Hall sensor 100, and the detection method includes:

Step S1: obtaining the power supply sampling correction coefficient and the zero-point voltage offset sampling coefficient;

The power supply sampling correction coefficient is used to characterize the deviation between the actual voltage value of the power supply and the theoretical voltage value. This power supply is the power supply used to power the Hall sensors. A voltage sensor can be used to detect the actual voltage value of the power supply, and then the power supply sampling correction coefficient can be calculated according to the difference between the theoretical voltage value of the power supply and the actual voltage value. For example, the power sampling correction coefficient is the ratio of the theoretical voltage value to the actual voltage value. In this embodiment, the theoretical voltage value of the power supply is 5V, then the power supply sampling correction coefficient p can be calculated by the following formula:

Wherein, V _cc is the actual voltage value of the power supply detected by the voltage sensor.

The zero-point voltage shift sampling coefficient is used to represent the deviation between the actual value and the theoretical value of the voltage signal output by the Hall element of the Hall sensor when the wire to be tested has no current passing through the Hall sensor. The zero-point voltage offset sampling coefficient may be the difference between the theoretical value and the actual value. A voltage sensor can be used to detect the voltage value of the voltage signal output by the output terminal of the Hall element when the wire to be tested has no current passing through it. The Hall element can be the first Hall element 5 or the second Hall element 6 . In this implementation, the theoretical value of the voltage signal output by the Hall element of the Hall sensor when no current passes through the wire to be tested is 2.5v, and the zero-point voltage shift sampling coefficient z is calculated by the following formula:

z=2.5-V ₀

Wherein, V ₀ is the voltage value of the voltage signal output by the voltage sensor to detect the output terminal of the Hall element when the wire to be tested has no current passing through the voltage sensor.

Step S2: obtaining the temperature drift correction coefficient;

The temperature drift coefficient is used to characterize the effect of temperature on the measurement results of the Hall sensor. The relationship between the temperature of the Hall sensor and the temperature drift correction coefficient can be pre-calibrated, and the corresponding relationship between the temperature of the Hall sensor and the temperature drift correction coefficient can be stored in a temperature drift coefficient table in advance.

A temperature sensor is used to measure the temperature of the Hall sensor, and then a temperature drift correction coefficient corresponding to the temperature is obtained by querying the temperature drift coefficient table according to the temperature.

Step S3: Calculate the first current value of the current passing through the wire to be measured according to the following algorithm;

Among them, I ₀ is the first current value, V _out1 is the voltage value of the voltage signal output by the first Hall element 5, V _out2 is the voltage value of the voltage signal output by the second Hall element, and G is the sensitivity of the Hall sensor coefficient, T is the temperature drift correction coefficient, z is the zero-point voltage offset sampling coefficient, and p is the power supply sampling correction coefficient.

Step S4: Obtain the software linear error correction coefficient, and calculate the current value of the wire to be tested according to the following algorithm:

I _p =l·I ₀

Wherein, I _p is the current value of the current passing through the wire to be measured, I ₀ is the first current value, and l is the software linearity error correction coefficient;

Proceed to step S2.

The software linear error correction coefficient can be obtained according to the method of look-up table. The correspondence between the first current value I ₀ and the software linear error correction coefficient l can be pre-calibrated and stored in the software linear error correction coefficient table, and the software linear error correction coefficient table can be queried according to the first current value I ₀ to obtain the software linearity error correction coefficient l corresponding to the first current value I ₀ .

The measurement results of the Hall sensor are calibrated according to the power supply sampling correction coefficient, the zero point voltage offset sampling coefficient, the temperature drift correction coefficient and the software linear error correction coefficient, and the measured current value on the wire to be measured is more accurate.

In an exemplary embodiment, the wire to be tested is connected to an inverter of an automobile. The wire to be tested can be connected to the DC input of the inverter or the AC output of the inverter. Therefore, the detection method can measure the current value of the DC input terminal of the inverter or the AC output terminal of the inverter.

This application describes a number of embodiments, but the description is exemplary rather than restrictive, and it will be apparent to those of ordinary skill in the art that within the scope of the embodiments described in this application can be There are many more examples and implementations. Although many possible combinations of features are shown in the drawings and discussed in the detailed description, many other combinations of the disclosed features are possible. Unless expressly limited, any feature or element of any embodiment may be used in combination with, or may be substituted for, any other feature or element of any other embodiment.

This application includes and contemplates combinations with features and elements known to those of ordinary skill in the art. The embodiments, features and elements that have been disclosed in this application can also be combined with any conventional features or elements to form unique inventive solutions as defined by the claims. Any features or elements of any embodiment may also be combined with features or elements from other inventive arrangements to form another unique inventive arrangement defined by the claims. Accordingly, it should be understood that any of the features shown and/or discussed in this application may be implemented alone or in any suitable combination. Accordingly, the embodiments are not to be limited except in accordance with the appended claims and their equivalents. Furthermore, various modifications and changes may be made within the scope of the appended claims.

Furthermore, in describing representative embodiments, the specification may have presented methods and/or processes as a particular sequence of steps. However, to the extent that the method or process does not depend on the specific order of steps described herein, the method or process should not be limited to the specific order of steps described. Other sequences of steps are possible, as will be understood by those of ordinary skill in the art. Therefore, the specific order of steps set forth in the specification should not be construed as limitations on the claims. Furthermore, the claims directed to the method and/or process should not be limited to performing their steps in the order written, as those skilled in the art will readily appreciate that these orders may be varied and still remain within the spirit and scope of the embodiments of the present application Inside.

Claims (11)

1. a Hall sensor, is characterized in that, comprises: a first magnetic conductor, including a first end and a second end opposite to the first end; the second magnetic conductor includes a third end and a fourth end opposite to the third end; a first Hall element; and the second Hall element; Wherein, a first air gap is formed between the first end and the third end, a second air gap is formed between the second end and the fourth end, and the first magnetic conductor and the first A measurement hole for the wire to be measured to pass is formed between the two magnetic conductors, the first hall element is arranged in the first air gap, and the second hall element is arranged in the second air gap. 2 . The Hall sensor according to claim 1 , wherein the first magnetic conductor and the second magnetic conductor are both bar-shaped. 3 . 3 . The Hall sensor according to claim 2 , wherein the first and second magnetic conductors are arc-shaped structures; 4 . The middle portions of the first magnet conductor and the second magnet conductor are arched in a direction away from each other. 4 . The Hall sensor according to claim 3 , wherein the first magnetic conductor and the second magnetic conductor are in plane symmetry. 5 . 5. The Hall sensor according to any one of claims 1 to 4, wherein the Hall sensor further comprises a housing, and an annular cavity is provided in the housing; The first magnet conducting body, the second magnet conducting body, the first hall element and the second hall element are all arranged in the annular cavity. 6. The Hall sensor according to claim 5, wherein the housing comprises a top cover and a bottom case; The bottom case includes a bottom plate provided with a first through hole and a plurality of side plates arranged on the edge of the bottom plate; The top cover comprises a top plate provided with a second through hole and a cylinder connected to the top plate and coaxially arranged with the second through hole; Wherein, one end of the cylinder extends into the first through hole of the bottom plate. 7 . The Hall sensor according to claim 6 , wherein the casing and the bottom casing are connected by a snap connection. 8 . 8 . A current detection device, characterized in that , comprising the Hall sensor according to any one of claims 1 to 7 . 9 . The current detection device according to claim 8 , wherein the first Hall element and the second Hall element output a voltage signal when there is current passing through the wire to be tested; 10 . The current detection device further includes a first calculation unit, the first calculation unit is electrically connected to the first Hall element and the second Hall element; The first calculation unit calculates the current value of the current passing through the wire under test according to the following algorithm:

Among them, I _p is the current value of the current passing through the wire to be tested, V _out1 is the voltage value of the voltage signal output by the first Hall element, V _out2 is the voltage value of the voltage signal output by the second Hall element, and A ₀ is Conversion coefficient between magnetic field strength and voltage, γ is the conversion coefficient between current and magnetic field strength. 10 . The current detection device according to claim 8 , wherein the current detection device further comprises a second calculation unit, and the second calculation unit includes an arithmetic circuit, a second analog-to-digital conversion module and a second calculation module. 11 . ; The arithmetic circuit is electrically connected to the first Hall element and the second Hall element, and the first Hall element and the second Hall element are directed to each other when a current passes through the wire to be tested. The operation circuit outputs a voltage signal, and the operation circuit is used for averaging the voltage signals output by the first Hall element and the second Hall element to obtain an average voltage signal; The second analog-to-digital conversion module is used to convert the signal type of the average voltage signal from an analog signal to a digital signal; Calculate the current value of the current through the wire under test according to the following algorithm:

Among them, I _p is the current value of the current passing through the wire under test, V is the voltage value of the average voltage signal, A ₀ is the conversion coefficient between magnetic field strength and voltage, and γ is the conversion coefficient between current and magnetic field strength. 11. A current detection method, characterized in that, the detection method is implemented based on the Hall sensor according to any one of claims 1 to 7, and the detection method comprises: Obtain power supply sampling correction coefficient, zero-point voltage offset sampling coefficient and temperature drift correction coefficient; Calculate the first current value of the current through the wire under test according to the following algorithm;

Among them, I ₀ is the first current value, V _out1 is the voltage value of the voltage signal output by the first Hall element, V _out2 is the voltage value of the voltage signal output by the second Hall element, and G is the sensitivity coefficient of the Hall sensor , T is the temperature drift correction coefficient, z is the zero-point voltage offset sampling coefficient, and p is the power supply sampling correction coefficient; Obtain the software linear error correction coefficient, and calculate the current value of the wire under test according to the following algorithm: I _p =l·I ₀ Wherein, I _p is the current value of the current passing through the wire to be tested, I ₀ is the first current value, and l is the software linearity error correction coefficient.

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