Current sensor, current measurement method, device and storage medium

Abstract

The present application relates to the field of current measurement technology, and discloses a current sensor, a current measurement method, a device and a storage medium. The current sensor includes: a magnetic field acquisition module, including a three-axis magnetic sensor chip, for acquiring the current magnetic field information around it; a driving module, for driving the three-axis magnetic sensor chip to rotate along a rotating circle; a motion information module, for acquiring the current rotation position information of the three-axis magnetic sensor chip; a control module, respectively connected to the magnetic field acquisition module, the driving module and the motion information module, for acquiring the corresponding relationship between the rotation position and the magnetic field information of the three-axis magnetic sensor chip, and determining the current current value of the conductor to be measured based on the corresponding relationship. The present application realizes the accurate measurement of the conductor current in a non-contact manner under the premise that the position of the conductor and the current sensor is not fixed through the coordinated action of the magnetic field acquisition module, the driving module, the motion information module and the control module, and has the beneficial effects of simple structure and high measurement accuracy.

Description

Technical Field

[0001] The present invention relates to the field of current measurement technology, and in particular to a current sensor, a current measurement method, a device and a storage medium. Background Art

[0002] In order to achieve non-contact measurement of the current of a conductor, the existing current sensor generally places a magnetic sensor unit on the periphery of the conductor to measure the magnetic field around the conductor, and then determines the current value to be measured of the conductor.

[0003] Since the magnetic field around the magnetic sensor unit is weak, the current value to be measured generally has a large error due to the measurement accuracy of the magnetic sensor unit. In order to improve the problem of weak magnetic field around the magnetic sensor, a magnetic field around the magnetic sensor is generally enhanced by a magnetic focusing ring, thereby reducing the measurement error of the current value to be measured. Since the volume of the magnetic focusing ring is large, the volume of the current sensor is generally large.

[0004] Furthermore, in order to achieve a small volume and accurately obtain the current value to be measured, a dot matrix current sensor is generally used, that is, without adding a magnetic focusing ring, the number of magnetic sensing units in the current sensor is set to multiple, and the multiple magnetic sensing units are arranged in a circular array on the periphery of the conductor to be measured and the conductor to be measured is limited to the central area of ​​the circular array. The output of each magnetic sensing unit is summed or averaged to determine the current value to be measured of the conductor. The current value to be measured is greatly affected by the number of magnetic sensing units. The more magnetic sensing units there are, the more accurate the current value to be measured is. When the measuring conductor is freely set in the internal area surrounded by the circular array, since the magnetic sensing unit can only measure the magnetic field in a specific direction, the current value to be measured generally has a large error, mainly due to the influence of the conductor to be measured being far away from the central area of ​​the circular array or being tilted relative to the circular array. Summary of the invention

[0005] The main purpose of the present invention is to provide a current sensor, a current measurement method, a device and a storage medium, aiming to improve the problem of low current measurement accuracy caused by the unfixed position of the current sensor and the measuring conductor.

[0006] To achieve the above object, the present invention provides a current sensor, comprising:

[0007] A magnetic field acquisition module, including a three-axis magnetic sensor chip, is used to obtain current magnetic field information around the three-axis magnetic sensor chip;

[0008] A driving module, used for driving the three-axis magnetic sensor chip to rotate along a rotating circle;

[0009] A motion information module, used to obtain current rotation position information of the three-axis magnetic sensor chip;

[0010] A control module is respectively connected to the magnetic field acquisition module, the driving module and the motion information module, and is used to obtain the corresponding relationship between the rotation position of the three-axis magnetic sensor chip and the magnetic field information, and determine the current current value of the conductor to be measured according to the corresponding relationship, wherein the conductor to be measured is located in the area surrounded by the rotating circle.

[0011] Optionally, the control module is used to control the movement of the driving module to make the three-axis magnetic sensor chip rotate along a first direction;

[0012] The control module is further used to determine whether the three-axis magnetic sensor chip rotates to at least one preset position through the motion information module;

[0013] The control module is further configured to obtain current magnetic field information around the three-axis magnetic sensor chip when determining that the three-axis magnetic sensor chip rotates to the at least one preset position.

[0014] Optionally, the rotating circle includes m preset positions, where m>1, so as to obtain magnetic field information of multiple preset positions;

[0015] The current current value is related to the placement position of the conductor to be measured and the magnetic field information corresponding to the m preset positions.

[0016] Optionally, the three-axis magnetic sensor chip includes an X-axis magnetic sensor unit, a Y-axis magnetic sensor unit and a Z-axis magnetic sensor unit, wherein the X-axis magnetic sensor unit is used to sense the magnetic field strength along the X-axis direction around the three-axis magnetic sensor chip and output an X-axis electrical signal; the Y-axis magnetic sensor unit is used to sense the magnetic field strength along the Y-axis direction around the three-axis magnetic sensor chip and output a Y-axis electrical signal; the Z-axis magnetic sensor unit is used to sense the magnetic field strength along the Z-axis direction around the three-axis magnetic sensor chip and output a Z-axis electrical signal; the X-axis direction, the Y-axis direction and the Z-axis direction are orthogonal to each other;

[0017] The magnetic field information corresponding to each preset position includes the X-axis electrical signal, the Y-axis electrical signal and the Z-axis electrical signal;

[0018] The current value I conforms to the formula:

[0019]

[0020] Among them, H ix H is the X-axis electrical signal of the three-axis magnetic sensor chip at the i-th rotation position; iy H is the Y-axis electrical signal of the three-axis magnetic sensor chip at the i-th rotation position; iz is the Z-axis electrical signal of the three-axis magnetic sensor chip at the i-th rotation position; k is related to the placement position of the wire to be tested.

[0021] Optionally, when the wire to be measured is orthogonal to the first plane where the rotating circle is located, k is a preset fixed value;

[0022] When the wire to be measured is obliquely intersecting the first plane, k=k1×k2, where k1 is a constant, and k2 is related to the magnetic field information corresponding to the m preset positions;

[0023] Optionally, the Z-axis direction is parallel to the first plane;

[0024] When the wire to be tested is obliquely intersecting the first plane in the X-axis direction,

[0025]

[0026] Among them, max(H 1z , …, H mz ) is the maximum value of each Z-axis electrical signal in the magnetic field information corresponding to the m preset positions; max(H 1y , …, H my ) is the maximum value of each Y-axis electrical signal in the magnetic field information corresponding to the m preset positions.

[0027] Optionally, the motion information module includes a grating and a photoelectric gate sensor;

[0028] The grating is fixedly connected to the three-axis magnetic sensor chip;

[0029] The photoelectric gate sensor is used to sense the position of the grating.

[0030] In addition, to achieve the above object, the present invention also proposes a current measurement method, which is applied to the current sensor to detect the current of the wire to be measured, and the method includes:

[0031] Acquire the current magnetic field information around the three-axis magnetic sensor chip in real time;

[0032] Driving the three-axis magnetic sensor chip to rotate along a rotating circle, wherein the conductor to be measured is located in an area surrounded by the rotating circle;

[0033] When the three-axis magnetic sensor chip is in a rotating state, obtaining current rotation position information of the three-axis magnetic sensor chip, and determining whether the three-axis magnetic sensor chip passes through a preset position of the rotation circle according to the current rotation position information, wherein the preset positions include a plurality of positions;

[0034] When it is determined that the three-axis magnetic sensor chip passes through the preset position, current magnetic field information around the three-axis magnetic sensor chip is used as magnetic field information corresponding to the preset position, thereby obtaining a corresponding relationship between the rotation position of the three-axis magnetic sensor chip and the magnetic field information;

[0035] The current value of the conductor to be tested is determined according to the corresponding relationship between the rotation position and the magnetic field information.

[0036] In addition, to achieve the above-mentioned purpose, the present invention also provides a current measuring device, which includes: a memory, a processor, and a current measuring program stored in the memory and executable on the processor, wherein the current measuring program is configured to implement the steps of the current measuring method.

[0037] In addition, to achieve the above-mentioned purpose, the present invention further provides a storage medium, on which a current measurement program is stored, and when the current measurement program is executed by a processor, the steps of the current measurement method are implemented.

[0038] The present invention obtains the current magnetic field information around the three-axis magnetic sensor chip in real time; drives the three-axis magnetic sensor chip to rotate along the rotating circle, wherein the conductor to be measured is located in the area surrounded by the rotating circle; when the three-axis magnetic sensor chip is in a rotating state, obtains the current rotation position information of the three-axis magnetic sensor chip, and determines whether the three-axis magnetic sensor chip passes through the preset position of the rotating circle according to the current rotation position information, and the preset position includes multiple; when determining that the three-axis magnetic sensor chip passes through the preset position, the current magnetic field information around the three-axis magnetic sensor chip is used as the magnetic field information corresponding to the preset position, and then the corresponding relationship between the rotation position and the magnetic field information of the three-axis magnetic sensor chip is obtained; according to the corresponding relationship between the rotation position and the magnetic field information, the current current value of the conductor to be measured is determined. Through the coordinated action of the magnetic field acquisition module, the drive module, the motion information module and the control module, the accurate measurement of the conductor current is realized in a non-contact manner under the premise that the positions of the conductor and the current sensor are not fixed, and the beneficial effects of simple structure and high measurement accuracy are achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is a structural block diagram of a first embodiment of a current sensor of the present invention;

[0040] Figure 2 This is a schematic diagram of the eccentricity of the present invention;

[0041] Figure 3 It is a flow chart of the first embodiment of the current measurement method of the present invention;

[0042] Figure 4 It is a flow chart of a second embodiment of a current measurement method of the present invention;

[0043] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0044] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0045] Reference Figure 1 , Figure 1 FIG. 4 is a structural block diagram of a first embodiment of a current sensor according to the present invention.

[0046] In this embodiment, the current sensor includes a control module 10 and a magnetic field acquisition module 20, a driving module 30 and a motion information module 40 respectively connected to the control module.

[0047] The magnetic field acquisition module 20 includes a three-axis magnetic sensor chip and is used to acquire current magnetic field information around the three-axis magnetic sensor chip.

[0048] It is understandable that the three-axis magnetic sensor chip is an integrated circuit that can simultaneously measure the magnetic field strength in three-dimensional space (three orthogonal axes of X, Y, and Z). In this embodiment, the three-axis magnetic sensor chip can be based on but not limited to the Hall effect or anisotropic magnetoresistance effect, giant magnetoresistance effect, tunneling magnetoresistance effect and other principles. These chips are widely used in navigation systems, electronic compasses, drone positioning, attitude sensing of mobile phones and tablets, industrial automation control and other fields. It can be used to accurately sense the magnetic field changes in the environment, and due to its high integration, it can achieve all-round real-time monitoring of the magnetic field on a single chip. In practical applications, the three-axis magnetic sensor chip can not only provide static magnetic field data, but also detect dynamically changing magnetic field information, which plays an important role in estimating the position, direction and speed of moving objects. Through the corresponding signal processing algorithm, the data accuracy can be further improved and the influence of external noise interference can be reduced. In this embodiment, the magnetic field acquisition module 20 installs the three-axis magnetic sensor chip on the rotating and connecting mechanism so that the three-axis magnetic sensor chip moves on a fixed circumference, detects the magnetic field distribution of each point on the circumference, and the processed three-dimensional magnetic field data can be pushed to the control module in real time. The sensor uses only one chip, and there is no need to match the chip, and the corresponding relationship between the position and the magnetic field data is obtained in real time. The whole process is a continuous process, ensuring that the sensor can monitor the three-dimensional magnetic field changes in the environment in real time.

[0049] Figure 2This is a schematic diagram of the eccentricity. When the cylindrical conductor is located at the center of the circle, the magnetic field direction A generated at the three-axis magnetic sensor chip is parallel to the sensitivity direction B of the three-axis magnetic sensor chip, and the sensor works normally. When the conductor deviates from the original position or tilts, the magnetic field direction A' generated at the position of the three-axis magnetic sensor chip is not parallel to the sensitivity direction B' of the three-axis magnetic sensor chip. The eccentricity caused by the deviation of the conductor from the original position or tilt will cause the magnetic field generated at the position of the three-axis magnetic sensor chip to be not parallel to the sensitivity direction of the three-axis magnetic sensor chip, making the accuracy of collecting the three-axis magnetic field information low, resulting in a large deviation in the measured current value.

[0050] The driving module 30 is used to drive the three-axis magnetic sensor chip to rotate along a rotating circle.

[0051] It should be understood that in this embodiment, the driving module is composed of a motor, a transmission mechanism and a rotating platform. Among them, the motor provides power, and the transmission mechanism converts the linear motion or high-speed rotation of the motor into a low-speed stable rotation suitable for the three-axis magnetic sensor chip. The magnetic field acquisition module is connected to the rotating platform of the driving module through the three-axis magnetic sensor chip. When the driving module is working, it will drive the rotating platform through the transmission mechanism to make the three-axis magnetic sensor chip rotate along a preset circular trajectory. This embodiment does not limit the structure of the driving module, and is not limited to the structure described in the embodiments detailed herein. All technical solutions obtained in the form of equivalent replacement or equivalent transformation based on the contents disclosed in the present invention are deemed to be within the scope of protection required by the present invention as long as they do not exceed the spirit and scope disclosed by the present invention.

[0052] The motion information module 40 is used to obtain the current rotation position information of the three-axis magnetic sensor chip.

[0053] It should be understood that in this embodiment, the motion information module 40 includes a grating and a photoelectric gate sensor. The grating is fixedly connected to the three-axis magnetic sensor chip. The photoelectric gate sensor is used to sense the position of the grating. The grating is usually an encoding disk with holes or lines. The grating rotates with the monitored object, and the photoelectric gate is fixed at a specific position. When the holes or lines on the grating pass through the photoelectric gate, periodic blocking and transmission phenomena will be formed. When the grating rotates, the light source inside the photoelectric gate emits light, which is irradiated onto the receiver through the holes or lines of the grating. When the holes or lines of the grating block the light, the light intensity received by the receiver will change, thereby generating a level signal. The photoelectric gate sensor converts these light intensity changes into electrical signals, and performs shaping, amplification and other processing through the built-in circuit to generate a series of pulse signals. Each pulse signal represents a unit displacement of the grating. The motion information module 40 can accurately measure the rotation speed, angle and rotation direction of the grating and other motion information by counting the number and frequency of these pulse signals, and send these data to the control module 10 in real time. The motion information module 40 uses a grating and a matching photoelectric gate to determine the current rotation position of the three-axis magnetic sensor chip, which can provide detailed information about the dynamic behavior of the three-axis magnetic sensor chip, and is helpful to achieve accurate motion control and state monitoring. This embodiment does not limit the structure of the motion information module, and is not limited to the structure described in the embodiments detailed herein. All technical solutions obtained in the form of equivalent replacement or equivalent transformation based on the content disclosed in the present invention are deemed to be within the scope of protection claimed by the present invention as long as they do not exceed the spirit and scope disclosed by the present invention.

[0054] The control module 10 is respectively connected to the magnetic field acquisition module 20, the driving module 30 and the motion information module 40, and is used to obtain the corresponding relationship between the rotation position of the three-axis magnetic sensor chip and the magnetic field information, and determine the current current value of the conductor to be tested based on the corresponding relationship, wherein the conductor to be tested is located in the area surrounded by the rotating circle.

[0055] It should be understood that, in addition to calculating the current value, the control module 10 is also used to issue various instructions inside the sensor to the control parts of other modules.

[0056] This embodiment obtains the current magnetic field information around the three-axis magnetic sensor chip through the magnetic field acquisition module; the driving module drives the three-axis magnetic sensor chip to rotate along the rotating circle; the motion information module obtains the current rotation position information of the three-axis magnetic sensor chip; the control module obtains the corresponding relationship between the rotation position and the magnetic field information of the three-axis magnetic sensor chip, and determines the current current value of the conductor to be measured based on the corresponding relationship. Through the coordinated action of the magnetic field acquisition module, the driving module, the motion information module and the control module, the accurate measurement of the conductor current is achieved in a non-contact manner under the premise that the position of the conductor and the current sensor is not fixed, which has the beneficial effects of simple structure and high measurement accuracy.

[0057] Based on the structural block diagram of the first embodiment described above, a second embodiment of the current sensor of the present invention is proposed.

[0058] In this embodiment, the control module 10 is used to control the movement of the driving module 30 so that the three-axis magnetic sensor chip rotates along a first direction.

[0059] It should be understood that, in this embodiment, the first direction is preset to clockwise rotation, and the driving module 30 drives the three-axis magnetic sensor chip to rotate along a rotating circle. In this embodiment, the rotating circle includes m preset positions, where m>1, so as to obtain the magnetic field information of multiple preset positions; the current current value is related to the placement position of the conductor to be measured and the magnetic field information corresponding to the m preset positions.

[0060] The control module 10 is further configured to determine, through the motion information module 40 , whether the three-axis magnetic sensor chip rotates to at least one preset position.

[0061] It should be noted that, in this embodiment, when the three-axis magnetic sensor chip starts to rotate, the magnetic field acquisition module 20 starts real-time monitoring of the surrounding magnetic field strength on the three orthogonal axes X, Y, and Z. Whenever the magnetic field change caused by the rotation of the three-axis magnetic sensor chip is detected and the counter in the motion information module 40 increases, the three-dimensional magnetic field data value at the current moment is synchronously acquired to ensure that each incremental position corresponds to a set of accurate magnetic field readings. This process will continue until the control module 10 detects that the three-axis magnetic sensor chip has completed a complete rotation cycle, that is, it has rotated one circle. At this time, three-dimensional magnetic field data points evenly distributed on the entire circumference will be collected. By continuously acquiring the three-dimensional magnetic field data measured by the three-axis magnetic sensor chip at different rotation angles, and combining mathematical models and algorithm processing, the accurate magnetic field distribution within the entire circumference can be finally restored.

[0062] The control module 10 is further configured to obtain current magnetic field information around the three-axis magnetic sensor chip when determining that the three-axis magnetic sensor chip rotates to at least one preset position.

[0063] It should be understood that when the three-axis magnetic sensor chip rotates with the object being measured, the three orthogonally arranged magnetic sensitive elements inside it will continuously sense the changes in the components of the surrounding magnetic field in the three axes of X, Y, and Z. The communication interface control module regularly reads the values ​​in the registers output by the three-axis magnetic sensor chip. These values ​​correspond to the magnetic field strength of the X-axis, Y-axis, and Z-axis, that is, the magnetic field measurement values ​​of each axis of the three-axis magnetic field sensor chip are Hx, Hy, and Hz. As the three-axis magnetic sensor chip rotates, the system continuously records the corresponding three-dimensional magnetic field measurement values ​​at each angular position.

[0064] It can be understood that the three-axis magnetic sensor chip includes an X-axis magnetic sensor unit, a Y-axis magnetic sensor unit and a Z-axis magnetic sensor unit, wherein the X-axis magnetic sensor unit is used to sense the magnetic field strength along the X-axis direction around the three-axis magnetic sensor chip and output an X-axis electrical signal; the Y-axis magnetic sensor unit is used to sense the magnetic field strength along the Y-axis direction around the three-axis magnetic sensor chip and output a Y-axis electrical signal; the Z-axis magnetic sensor unit is used to sense the magnetic field strength along the Z-axis direction around the three-axis magnetic sensor chip and output a Z-axis electrical signal; the X-axis direction, the Y-axis direction and the Z-axis direction are orthogonal to each other; the magnetic field information corresponding to each preset position includes an X-axis electrical signal, a Y-axis electrical signal and a Z-axis electrical signal.

[0065] The current value I conforms to the formula:

[0066]

[0067] Among them, H ix is the X-axis electrical signal of the three-axis magnetic sensor chip at the i-th rotation position; H iy is the Y-axis electrical signal of the three-axis magnetic sensor chip at the i-th rotation position; H iz is the Z-axis electrical signal of the three-axis magnetic sensor chip at the i-th rotation position; k is related to the placement position of the wire to be tested.

[0068] In this embodiment, the electrical signal refers to a voltage value proportional to the magnetic field strength. According to Ampere's loop theorem, in a steady magnetic field, the line integral of the magnetic induction intensity B along any closed path is equal to the algebraic sum of the currents enclosed by the closed path multiplied by the magnetic permeability. Since the magnetic permeability in the air is uniform and approximately equal to the magnetic permeability of a vacuum, the relationship between the magnetic field strength on the loop and the enclosed current after the change is as follows:

[0069] ∮Bdl=u0ΣI;

[0070] Assuming that the grating resolution is φ°, there are 360 / φ possible positions of the magnetic field sensor, recorded as m, and the count value of the counter after one rotation is m. When the initial count value is 1 and the counter is recorded as n (1≤n≤m), the components of the three axes of the three-axis magnetic field sensor chip, X, Y, and Z, are Hxn, Hyn, and Hzn respectively. The magnetic field value Hn collected at each point and the magnetic field output value of each axis collected have the following relationship:

[0071]

[0072] After discretization, assuming that the radius of the moving circle of the three-axis magnetic sensor chip is r, and k is a certain proportional coefficient related to n and r, the approximate relationship between the measured current I and the magnetic field value Hn at each acquisition point can be obtained by the principle of integration:

[0073]

[0074] When the measured wire is orthogonal to the first plane where the rotating circle is located, k is a preset fixed value; when the measured wire is oblique to the first plane, k=k1×k2, where k1 is a constant and k2 is related to the magnetic field information corresponding to the m preset positions.

[0075] It is understandable that the above k2 may have different values, which are related to the inclination angle of the wire to be measured. The Z-axis direction is parallel to the first plane. When the wire to be measured is oblique to the first plane in the X-axis direction,

[0076]

[0077] Among them, max(H 1z , …, H mz ) is the maximum value of each Z-axis electrical signal in the magnetic field information corresponding to the m preset positions; max(H 1y , …, H my ) is the maximum value of each Y-axis electrical signal in the magnetic field information corresponding to the m preset positions.

[0078] In this embodiment, the control module controls the movement of the driving module to rotate the three-axis magnetic sensor chip along the first direction; the control module determines whether the three-axis magnetic sensor chip rotates to at least one preset position through the motion information module; when the control module determines that the three-axis magnetic sensor chip rotates to at least one preset position, the control module obtains the current magnetic field information around the three-axis magnetic sensor chip, and can obtain multi-directional magnetic field information of the three-axis magnetic sensor chip in real time, thereby improving the comprehensiveness and accuracy of magnetic field measurement.

[0079] Reference Figure 3 , Figure 3 FIG. 4 is a flow chart of a first embodiment of a current measurement method according to the present invention.

[0080] Step S10, obtaining the current magnetic field information around the three-axis magnetic sensor chip in real time.

[0081] It should be understood that the magnetic field acquisition module obtains the current magnetic field information around the three-axis magnetic sensor chip. The working environment of the sensor is to measure low-frequency AC current or low-frequency DC current. The three-axis magnetic sensor chip collects magnetic field data including initializing the internal circuit after power-on, and setting the sensor's working mode, sampling rate, resolution, range and other parameters through the I2C or SPI interface according to application requirements. The sensor contains three mutually perpendicular magnetic sensitive elements, corresponding to the X, Y, and Z axis directions respectively. When the external magnetic field acts on the sensor, each axial element will generate a voltage signal proportional to the magnetic field strength. These weak voltage signals will be amplified and adjusted by the internal integrated signal conditioning circuit for further processing. The amplified analog signal will be converted into a digital signal through the ADC. The main controller reads the digitized magnetic field strength values ​​of the three axes of X, Y, and Z from the three-axis magnetic sensor chip through the I2C or SPI interface. After receiving the original value, the controller may need to calibrate the data to improve the accuracy, such as offset compensation and temperature compensation, and perform necessary calculations according to the actual application scenario, such as calculating geomagnetic inclination, magnetic declination, and heading angle information.

[0082] Step S20, driving the three-axis magnetic sensor chip to rotate along a rotating circle, wherein the conductor to be measured is located in an area surrounded by the rotating circle.

[0083] It should be understood that the drive module drives the three-axis magnetic sensor chip to rotate along the circumference of the rotation. When the drive module is started, it will drive the three-axis magnetic sensor chip to make a circular motion around a fixed axis. During this process, the three-axis magnetic sensor chip continuously captures and converts the magnetic field change information into electrical signals.

[0084] Step S30, when the three-axis magnetic sensor chip is in a rotating state, obtaining current rotation position information of the three-axis magnetic sensor chip, and determining whether the three-axis magnetic sensor chip passes through a preset position of the rotation circle according to the current rotation position information, wherein the preset positions include multiple ones.

[0085] It should be noted that, in this embodiment, the motion information module includes a grating and a photoelectric gate sensor. The grating is a coding disk, which is used to accurately measure the rotation angle or position information. The driving module is composed of a motor, a transmission mechanism and a rotating platform. In order to avoid external interference caused by motor vibration on the acquisition of the three-axis magnetic sensor chip, the three-axis magnetic sensor chip and the grating are fixed on the same rotating platform, and the rotating platform is driven to rotate by the transmission mechanism. Then the three-axis magnetic sensor chip and the grating rotate synchronously, so that there is no direct contact between the motor and the three-axis magnetic sensor chip. Since the grating rotates with the three-axis magnetic sensor chip, and the photoelectric gate is fixed at a specific position, when the holes or lines on the grating pass through the photoelectric gate sensor, periodic blocking and transmission phenomena will be formed. When the grating rotates, the light source inside the photoelectric gate emits light, which is irradiated onto the receiver through the holes or lines of the grating. When the holes or lines of the grating block the light, the light intensity received by the receiver will change, thereby generating a level signal. According to the analysis of the level signal, the rotation position information of the three-axis magnetic sensor chip is obtained.

[0086] Step S40, when it is determined that the three-axis magnetic sensor chip passes through the preset position, the current magnetic field information around the three-axis magnetic sensor chip is used as the magnetic field information corresponding to the preset position, thereby obtaining the corresponding relationship between the rotation position of the three-axis magnetic sensor chip and the magnetic field information.

[0087] It is understandable that the system drives the electromagnetic motor to rotate the connection structure, which includes the components of the three-axis magnetic sensor chip and the grating. When the electromagnetic motor receives the command to start running, the counter is started to count at the same time. As the three-axis magnetic sensor chip rotates with the motor drive, the magnetic field acquisition module will monitor and record the three-dimensional magnetic field data around the three-axis magnetic sensor chip at each incremental position in real time, including the magnetic field measurement values ​​of the X-axis, Y-axis, and Z-axis. Every time the counter increases by one unit, the magnetic field acquisition module will obtain and save the three-dimensional magnetic field data at the current moment again. This process continues until it is detected that the three-axis magnetic sensor chip has completed a full circle rotation.

[0088] Step S50, determining the current value of the conductor to be tested according to the corresponding relationship between the rotation position and the magnetic field information.

[0089] The control module obtains the corresponding relationship between the rotation position of the three-axis magnetic sensor chip and the magnetic field information, and determines the current current value of the conductor to be measured according to the corresponding relationship, wherein the conductor to be measured is located in the area surrounded by the rotating circle.

[0090] This embodiment obtains the current magnetic field information around the three-axis magnetic sensor chip in real time; drives the three-axis magnetic sensor chip to rotate along the rotating circle, wherein the conductor to be measured is located in the area surrounded by the rotating circle; when the three-axis magnetic sensor chip is in a rotating state, obtains the current rotation position information of the three-axis magnetic sensor chip, and determines whether the three-axis magnetic sensor chip passes through a preset position of the rotating circle based on the current rotation position information, and the preset position includes multiple; when determining that the three-axis magnetic sensor chip passes through the preset position, the current magnetic field information around the three-axis magnetic sensor chip is used as the magnetic field information corresponding to the preset position, and then the corresponding relationship between the rotation position and the magnetic field information of the three-axis magnetic sensor chip is obtained; based on the corresponding relationship between the rotation position and the magnetic field information, the current current value of the conductor to be measured is determined. Through the coordinated action of the magnetic field acquisition module, the drive module, the motion information module and the control module, the accurate measurement of the conductor current is realized in a non-contact manner under the premise that the position of the conductor and the current sensor is not fixed, which has the beneficial effects of simple structure and high measurement accuracy.

[0091] Reference Figure 4 , Figure 4 FIG. 4 is a flow chart of a second embodiment of a current measurement method according to the present invention.

[0092] Before step 40 of the second embodiment, the method further includes:

[0093] Step S401: The control module controls the driving module to move so that the three-axis magnetic sensor chip rotates along a first direction.

[0094] It is understandable that when the three-axis magnetic sensor chip rotates with the object being measured, the three orthogonally arranged magnetic sensitive elements inside it will continuously sense the changes in the components of the surrounding magnetic field in the three axes of X, Y, and Z. The communication interface control module regularly reads the values ​​in the registers output by the three-axis magnetic sensor chip. These values ​​correspond to the magnetic field strength of the X, Y, and Z axes. As the three-axis magnetic sensor chip rotates, the system continuously records the corresponding three-dimensional magnetic field measurement values ​​at each angular position until a complete circle rotation is completed.

[0095] Step S402: The control module determines, through the motion information module, whether the three-axis magnetic sensor chip rotates to at least one preset position.

[0096] It should be noted that the control module and the motion information module work closely together to ensure that the three-axis magnetic sensor chip completes the rotation operation in the expected manner and reaches the preset detection position. In actual operation, the control module monitors and analyzes the data feedback from the motion information module in real time. These data contain key information about the motion state of the three-axis magnetic sensor chip, such as the current position, speed, acceleration, and angular position. The motion information module can capture and record the angle changes of the three-axis magnetic sensor chip during the rotation process with high precision. When the three-axis magnetic sensor chip starts to rotate in the first direction, the motion information module continuously collects its dynamic data and transmits these data to the control module in real time.

[0097] Step S403 : when determining that the three-axis magnetic sensor chip rotates to at least one preset position, the control module obtains current magnetic field information around the three-axis magnetic sensor chip.

[0098] It should be understood that in this embodiment, every time the three-axis magnetic sensor chip rotates a circle, the control module will receive the information transmitted by the motion information module. After receiving this information, the control module compares and calculates the current position of the three-axis magnetic sensor chip with the preset position list through the built-in algorithm. Once it is confirmed that the three-axis magnetic sensor chip has reached any preset position point, it will collect the magnetic field data at that moment.

[0099] In this embodiment, the control module controls the movement of the driving module to rotate the three-axis magnetic sensor chip along the first direction; the control module determines whether the three-axis magnetic sensor chip rotates to at least one preset position through the motion information module; when the control module determines that the three-axis magnetic sensor chip rotates to at least one preset position, the control module obtains the current magnetic field information around the three-axis magnetic sensor chip, which can more completely and accurately describe the real distribution of the magnetic field in the three-dimensional space and improve the measurement accuracy.

[0100] In addition, to achieve the above objectives, the present invention also proposes a current measuring device, which includes: a memory, a processor, and a current measuring program stored in the memory and executable on the processor, wherein the current measuring program is configured to implement the steps of the current measuring method as described above.

[0101] Since the current measuring device adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0102] In addition, an embodiment of the present invention further provides a storage medium, on which a current measurement program is stored. When the current measurement program is executed by a processor, the steps of the current measurement method described above are implemented.

[0103] Since the storage medium adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0104] It should be understood that the above is only an example and does not constitute any limitation on the technical solution of the present invention. In specific applications, technicians in this field can make settings as needed, and the present invention does not limit this.

[0105] It should be noted that the workflow described above is merely illustrative and does not limit the scope of protection of the present invention. In practical applications, technicians in this field can select part or all of them according to actual needs to achieve the purpose of the present embodiment, and no limitation is made here.

[0106] In addition, for technical details that are not described in detail in this embodiment, reference can be made to the engineering mode control method provided in any embodiment of the present invention, and will not be repeated here.

[0107] In addition, it should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0108] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0109] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes a number of instructions for a terminal device (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in each embodiment of the present invention.

[0110] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A current sensor, characterized in that: include: A magnetic field acquisition module, including a three-axis magnetic sensor chip, is used to obtain current magnetic field information around the three-axis magnetic sensor chip; A driving module, used for driving the three-axis magnetic sensor chip to rotate along a rotating circle; A motion information module, used to obtain current rotation position information of the three-axis magnetic sensor chip; a control module, connected to the magnetic field acquisition module, the driving module and the motion information module respectively, for obtaining a corresponding relationship between the rotation position of the three-axis magnetic sensor chip and the magnetic field information, and determining a current current value of the conductor to be measured according to the corresponding relationship, wherein the conductor to be measured is located in an area surrounded by the rotating circle; The three-axis magnetic sensor chip includes an X-axis magnetic sensor unit, a Y-axis magnetic sensor unit and a Z-axis magnetic sensor unit, wherein the X-axis magnetic sensor unit is used to sense the magnetic field strength along the X-axis direction around the three-axis magnetic sensor chip and output an X-axis electrical signal; the Y-axis magnetic sensor unit is used to sense the magnetic field strength along the Y-axis direction around the three-axis magnetic sensor chip and output a Y-axis electrical signal; the Z-axis magnetic sensor unit is used to sense the magnetic field strength along the Z-axis direction around the three-axis magnetic sensor chip and output a Z-axis electrical signal; the X-axis direction, the Y-axis direction and the Z-axis direction are orthogonal to each other; The magnetic field information corresponding to each preset position includes the X-axis electrical signal, the Y-axis electrical signal and the Z-axis electrical signal; The current value I conforms to the formula: Among them, H ix H is the X-axis electrical signal of the three-axis magnetic sensor chip at the i-th rotation position; iy H is the Y-axis electrical signal of the three-axis magnetic sensor chip at the i-th rotation position; iz is the Z-axis electrical signal of the three-axis magnetic sensor chip at the i-th rotation position; k is related to the placement position of the wire to be tested; When the wire to be tested is orthogonal to the first plane of the rotating circle, k is a preset fixed value; When the wire to be measured is obliquely intersected with the first plane, k=k1×k2, wherein k1 is a constant, and k2 is related to the magnetic field information corresponding to the current rotation position information of the three-axis magnetic sensor chip; the Z-axis direction is parallel to the first plane; When the wire to be tested is obliquely intersecting the first plane in the X-axis direction, Among them, max(H 1z ,…,H mz ) is the maximum value of each Z-axis electrical signal in the magnetic field information corresponding to the m preset positions; max(H 1y ,…,H my ) is the maximum value of each Y-axis electrical signal in the magnetic field information corresponding to the m preset positions.

2. The current sensor according to claim 1, characterized in that: The control module is used to control the movement of the driving module so that the three-axis magnetic sensor chip rotates along a first direction; The control module is further used to determine whether the three-axis magnetic sensor chip rotates to at least one preset position through the motion information module; The control module is further configured to obtain current magnetic field information around the three-axis magnetic sensor chip when determining that the three-axis magnetic sensor chip rotates to the at least one preset position.

3. The current sensor according to claim 2, characterized in that: The rotating circle includes m preset positions, where m>1, so as to obtain magnetic field information of multiple preset positions; The current current value is related to the placement position of the conductor to be measured and the magnetic field information corresponding to the m preset positions.

4. The current sensor according to any one of claims 1 to 3, characterized in that: The motion information module includes a grating and a photoelectric gate sensor; The grating is fixedly connected to the three-axis magnetic sensor chip; The photoelectric gate sensor is used to sense the position of the grating.

5. A current measurement method, characterized in that: Using the current sensor as described in any one of claims 1 to 4 to detect the current of the conductor to be measured, the method comprises: Acquire the current magnetic field information around the three-axis magnetic sensor chip in real time; Driving the three-axis magnetic sensor chip to rotate along a rotating circle, wherein the conductor to be measured is located in an area surrounded by the rotating circle; When the three-axis magnetic sensor chip is in a rotating state, obtaining current rotation position information of the three-axis magnetic sensor chip, and determining whether the three-axis magnetic sensor chip passes through a preset position of the rotation circle according to the current rotation position information, wherein the preset positions include a plurality of positions; When it is determined that the three-axis magnetic sensor chip passes through the preset position, current magnetic field information around the three-axis magnetic sensor chip is used as magnetic field information corresponding to the preset position, thereby obtaining a corresponding relationship between the rotation position of the three-axis magnetic sensor chip and the magnetic field information; Determining the current value of the conductor to be tested according to the corresponding relationship between the rotation position and the magnetic field information; The three-axis magnetic sensor chip includes an X-axis magnetic sensor unit, a Y-axis magnetic sensor unit and a Z-axis magnetic sensor unit, wherein the X-axis magnetic sensor unit is used to sense the magnetic field strength along the X-axis direction around the three-axis magnetic sensor chip and output an X-axis electrical signal; the Y-axis magnetic sensor unit is used to sense the magnetic field strength along the Y-axis direction around the three-axis magnetic sensor chip and output a Y-axis electrical signal; the Z-axis magnetic sensor unit is used to sense the magnetic field strength along the Z-axis direction around the three-axis magnetic sensor chip and output a Z-axis electrical signal; the X-axis direction, the Y-axis direction and the Z-axis direction are orthogonal to each other; The magnetic field information corresponding to each preset position includes the X-axis electrical signal, the Y-axis electrical signal and the Z-axis electrical signal; The current value I conforms to the formula: Among them, H ix H is the X-axis electrical signal of the three-axis magnetic sensor chip at the i-th rotation position; iy H is the Y-axis electrical signal of the three-axis magnetic sensor chip at the i-th rotation position; iz is the Z-axis electrical signal of the three-axis magnetic sensor chip at the i-th rotation position; k is related to the placement position of the wire to be tested; When the wire to be tested is orthogonal to the first plane of the rotating circle, k is a preset fixed value; When the wire to be measured is obliquely intersected with the first plane, k=k1×k2, wherein k1 is a constant, and k2 is related to the magnetic field information corresponding to the current rotation position information of the three-axis magnetic sensor chip; the Z-axis direction is parallel to the first plane; When the wire to be tested is obliquely intersecting the first plane in the X-axis direction, Among them, max(H 1z ,…,H mz ) is the maximum value of each Z-axis electrical signal in the magnetic field information corresponding to the m preset positions; max(H 1y ,…,H my ) is the maximum value of each Y-axis electrical signal in the magnetic field information corresponding to the m preset positions.

6. A current measuring device, characterized in that: The device comprises: a memory, a processor, and a current measurement program stored in the memory and running on the processor, wherein the current measurement program is configured to implement the steps of the current measurement method according to claim 5 .

7. A storage medium, characterized in that: The storage medium stores a current measurement program, and when the current measurement program is executed by the processor, the steps of the current measurement method according to claim 5 are implemented.

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