A current sensor based on a plurality of sampling windings and an electronic device
By designing multiple sampling windings and compensation windings, combined with signal processing and compensation modules, the problem of low sampling accuracy of current sensors was solved, achieving more accurate current detection and improved anti-interference capabilities.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-09
- Publication Date
- 2026-06-09
AI Technical Summary
Existing current sensors suffer from uneven magnetic field distribution in the main magnetic core, resulting in a difference between the magnetic induction intensity at the sampling winding location and the magnetic induction intensity at the primary winding location. This makes it impossible to accurately characterize the excitation current of the primary winding, leading to a large sampling error in the detected current.
By employing a design with multiple sampling windings and compensation windings, and through the combination of induction modules, compensation modules, and processing modules, signal processing and compensation are performed using amplitude and phase detection units, amplification units, filtering units, phase-sensitive detection units, and control units, accurate characterization and error compensation of the primary winding excitation current are achieved.
It improves the sampling accuracy and anti-interference performance of the current sensor, reduces the impact of noise, enhances the robustness and anti-interference ability of the current sensor, and reduces the influence of excitation current on the detection current.
Smart Images
Figure CN122171866A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of sensor technology, specifically to a current sensor and electronic device based on multiple sampling windings. Background Technology
[0002] Power system failures can easily damage electrical equipment. Monitoring the current in power equipment can provide strong evidence for ensuring its safe operation. Current sensors, as the most effective testing method, are widely used in power systems.
[0003] Current sensors provided by related technologies typically involve winding a sampling winding on the main magnetic core. This sampling winding detects the induced electromotive force (EMF) of the main magnetic core, extracts the excitation current of the primary winding, and then uses a compensation module and compensation winding to perform reverse compensation on the excitation current, thus achieving the acquisition of the detected current. However, the magnetic field distribution of the main magnetic core is often non-uniform; the magnetic induction intensity at the sampling winding location differs from that at the primary winding location, and the induced EMF also varies at different locations on the main magnetic core. Therefore, these technologies cannot accurately characterize the excitation current of the primary winding, resulting in a large sampling error in the detected current. In other words, the sampling accuracy of current sensors provided by these technologies is low. Summary of the Invention
[0004] To address the low sampling accuracy problem in existing technologies, this application provides a current sensor based on multiple sampling windings, which may include: a sensing module, a compensation module, and a processing module. The sensing module includes a main magnetic core, an auxiliary magnetic core, multiple sampling windings, a primary winding, a secondary winding, and a compensation winding.
[0005] The primary winding is wound on both the main and auxiliary magnetic cores. The secondary winding is wound on both the main and auxiliary magnetic cores and is connected to the processing module. Multiple sampling windings are wound on the main magnetic core and are all connected to the input of the compensation module. The compensation winding is wound on the auxiliary magnetic core and is connected to the output of the compensation module.
[0006] Optionally, multiple sampling windings are used to acquire the induced electromotive force at different locations of the main magnetic core.
[0007] The compensation module is used to: determine the excitation current of the primary winding based on the induced electromotive force at each position, and output a compensation current based on the excitation current of the primary winding.
[0008] The compensating winding is used to compensate for the induced current in the secondary winding based on the compensating current.
[0009] The secondary winding is used to: obtain the induced electromotive force of the secondary winding.
[0010] The processing module is used to output a detection current based on the induced electromotive force of the secondary winding.
[0011] In some possible implementations, the compensation module includes an amplitude and phase detection unit, a first processing unit, and a control unit.
[0012] The input terminal of the amplitude and phase detection unit is connected to multiple sampling windings, the output terminal of the amplitude and phase detection unit is connected to the input terminal of the first processing unit, the output terminal of the first processing unit is connected to the input terminal of the control unit, the output terminal of the control unit is connected to the input terminal of the conversion unit, and the output terminal of the conversion unit is connected to the compensation winding.
[0013] Furthermore, the amplitude and phase detection unit is used to detect the amplitude and phase of the induced electromotive force at each location.
[0014] The first processing unit is used to determine the excitation current of the primary winding based on the amplitude and phase of the induced electromotive force at each position.
[0015] The control unit is used to perform proportional-integral-derivative control on the excitation current of the primary winding and output compensation current to the compensation winding.
[0016] In some other possible implementations, the processing module includes an amplification unit, a filtering unit, a phase-sensitive detection unit, and a second processing unit.
[0017] The input terminal of the amplification unit is connected to the secondary winding, the output terminal of the amplification unit is connected to the input terminal of the filter unit, the output terminal of the filter unit is connected to the input terminal of the phase-sensitive detector unit, the output terminal of the phase-sensitive detector unit is connected to the input terminal of the second processing unit, and the output terminal of the second processing unit is used to output the detection current.
[0018] Furthermore, the amplification unit is used to amplify the induced electromotive force of the secondary winding to obtain the amplified induced electromotive force.
[0019] The filtering unit is used to filter the amplified induced electromotive force to obtain the filtered induced electromotive force.
[0020] The phase-sensitive detector unit is used to rectify and phase-discriminate the filtered induced electromotive force to obtain the amplitude and phase of the filtered induced electromotive force.
[0021] The second processing unit is used to output the detection current based on the amplitude and phase of the filtered induced electromotive force and the correspondence between the amplitude and phase of the filtered induced electromotive force and the detection current.
[0022] For example, the measured value of the induced electromotive force of the sampling winding satisfies:
[0023]
[0024] Among them, e n N represents the measured value of the induced electromotive force of the nth sampling winding. 0n S represents the number of turns in the nth sampling winding. n Let l represent the cross-sectional area of the nth sampling winding. n N represents the magnetic path length of the nth sampling winding, N1 represents the number of turns of the primary winding wound on the main core / auxiliary core, and ω represents the angular frequency of the excitation current of the main core. I represents the phase of the excitation current of the main magnetic core. 01m The peak value of the excitation current of the main magnetic core is represented by t, where t represents time. Δe represents the calculated electromotive force at the nth sampling winding. n This represents the difference between the calculated electromotive force at the nth sampling winding and the measured induced electromotive force at the nth sampling winding.
[0025] For example, the first part of the primary winding is wound on the main magnetic core, and the second part of the primary winding is wound on the auxiliary magnetic core. The number of turns in the first and second parts of the primary winding can be the same.
[0026] The winding direction of the first part of the primary winding is opposite to that of the second part of the primary winding. In other words, the primary winding is connected in reverse on the main magnetic core and the auxiliary magnetic core (which can be simply referred to as reverse connection).
[0027] Optionally, the first part of the secondary winding is wound on the main magnetic core, and the second part of the secondary winding is wound on the auxiliary magnetic core. The number of turns in the first and second parts of the secondary winding can be the same.
[0028] The winding direction of the first part of the secondary winding is the same as the winding direction of the second part of the secondary winding.
[0029] Furthermore, this application also provides an electronic device including the aforementioned current sensor.
[0030] Compared with the prior art, the beneficial effects of this application are as follows:
[0031] The current sensor provided in this application may include a sensing module, a compensation module, and a processing module. The sensing module includes a main magnetic core, an auxiliary magnetic core, multiple sampling windings, a primary winding, a secondary winding, and a compensation winding. The primary winding is wound on the main magnetic core and the auxiliary magnetic core. The secondary winding is wound on the main magnetic core and is connected to the processing module. The multiple sampling windings are wound on the main magnetic core and are all connected to the input terminal of the compensation module. The compensation winding is wound on the auxiliary magnetic core and is connected to the output terminal of the compensation module. It can be seen that the use of multiple sampling windings in this application can solve the problem of errors in the detected current caused by the magnetic induction intensity at different positions of the main magnetic core. Multiple sampling windings can accurately characterize the excitation current of the primary winding, thereby improving the sampling accuracy of the current sensor.
[0032] This application amplifies the induced electromotive force (EMF) of the secondary winding through an amplification unit, filters the amplified EMF through a filtering unit, and rectifies and phase-discriminates the filtered EMF through a phase-sensitive detection unit to obtain the amplitude and phase of the filtered EMF. It can be seen that this application can more accurately detect changes in the amplitude and phase of the filtered EMF, while reducing the influence of noise and improving the anti-interference performance of the current sensor.
[0033] The control unit in this application uses PID control to dynamically adjust the amplitude and phase of the compensation current in real time, achieving adaptive compensation for primary excitation under different electromagnetic environments. This enhances the anti-interference capability and robustness of the current sensor, and reduces the influence of the primary winding excitation current on the detection current.
[0034] This application achieves zero magnetic flux in the main magnetic core by using the compensation current output from the compensation winding, thereby effectively offsetting the influence of the excitation current on measurement errors. Attached Figure Description
[0035] To more clearly illustrate the technical solutions in this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0036] Figure 1 This is a schematic structural diagram of a current sensor based on multiple sampling windings in an embodiment of this application;
[0037] Figure 2 This is a schematic structural diagram of the compensation module in an embodiment of this application;
[0038] Figure 3This is a schematic structural diagram of a processing module in an embodiment of this application;
[0039] Figure 4 This is a schematic diagram of the magnetic induction intensity distribution of the main magnetic core in an embodiment of this application. Detailed Implementation
[0040] The technical solutions in this application will now be described with reference to the accompanying drawings.
[0041] The terms "first," "second," etc., used in the specification, embodiments, claims, and drawings of this application are for distinguishing purposes only and should not be construed as indicating or implying relative importance or order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, such as including a series of steps or units. A method, system, product, or apparatus is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products, or apparatuses.
[0042] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.
[0043] This application provides a current sensor based on multiple sampling windings, such as... Figure 1 As shown. The current sensor 10 includes a sensing module, a compensation module 2, and a processing module 3. The sensing module includes a main magnetic core 11, an auxiliary magnetic core 12, multiple sampling windings 13, a primary winding 14, a secondary winding 15, and a compensation winding 16.
[0044] Primary winding 14 is wound on the main magnetic core 11 and auxiliary magnetic core 12. Secondary winding 15 is wound on the main magnetic core 11 and auxiliary magnetic core 12, and secondary winding 15 is connected to processing module 3. Multiple sampling windings 13 are wound on the main magnetic core 11, and all sampling windings 13 are connected to the input terminal of compensation module 2. Compensation winding 2 is wound on auxiliary magnetic core 3, and compensation winding 16 is connected to the output terminal of compensation module 2.
[0045] Optionally, multiple sampling windings 13 are used to: acquire the induced electromotive force at different positions of the main magnetic core 11.
[0046] The compensation module 2 is used to: determine the excitation current of the primary winding 14 based on the induced electromotive force at each position, and output a compensation current (which can be represented by I3) based on the excitation current of the primary winding 14.
[0047] The compensation winding 16 is used to compensate the induced current of the secondary winding 15 according to the compensation current.
[0048] The secondary winding 15 is used to: obtain the induced electromotive force of the secondary winding 15.
[0049] The processing module 3 is used to output a detection current (which can be represented by I) based on the induced electromotive force of the secondary winding 15.
[0050] In some possible implementations, such as Figure 2 As shown, the compensation module 2 includes an amplitude and phase detection unit 21, a first processing unit 22, and a control unit 23.
[0051] The input terminal of the amplitude and phase detection unit 21 is connected to each of the multiple sampling windings 13, the output terminal of the amplitude and phase detection unit 21 is connected to the input terminal of the first processing unit 22, the output terminal of the first processing unit 22 is connected to the input terminal of the control unit 23, and the output terminal of the control unit 23 is connected to the compensation winding 16. Figure 2 In the middle, R L Indicates load.
[0052] Furthermore, the amplitude and phase detection unit 21 is used to detect the amplitude and phase of the induced electromotive force at each position.
[0053] The first processing unit 22 is used to: determine the excitation current (using I0) of the primary winding 14 based on the amplitude and phase of the induced electromotive force at each position. 01 express).
[0054] The control unit 23 is used to: perform proportional-integral-derivative (PID) control on the excitation current of the primary winding 14, and output the compensation current I3 to the compensation winding 16.
[0055] In some other possible implementations, such as Figure 3 As shown, the processing module 3 includes an amplification unit 31, a filtering unit 32, a phase-sensitive detection unit 33, and a second processing unit 34.
[0056] The input terminal of the amplification unit 31 is connected to the secondary winding 15, the output terminal of the amplification unit 31 is connected to the input terminal of the filter unit 32, the output terminal of the filter unit 32 is connected to the input terminal of the phase-sensitive detector unit 33, the output terminal of the phase-sensitive detector unit 33 is connected to the input terminal of the second processing unit 34, and the output terminal of the second processing unit 34 is used to output the detection current I.
[0057] Since the induced electromotive force of the secondary winding 15 is relatively weak and subject to noise interference, it needs to be filtered and the interference eliminated. Therefore, the amplification unit 31 is used to amplify the induced electromotive force of the secondary winding 15 to obtain the amplified induced electromotive force.
[0058] The filtering unit 32 is used to filter the amplified induced electromotive force to obtain the filtered induced electromotive force.
[0059] The phase-sensitive detector unit 33 is used to rectify and phase-discriminate the filtered induced electromotive force to obtain the amplitude and phase of the filtered induced electromotive force.
[0060] The second processing unit 34 is used to: output the detection current I based on the amplitude and phase of the filtered induced electromotive force and the correspondence between the amplitude and phase of the filtered induced electromotive force and the detection current.
[0061] Optionally, the relationship between the amplitude and phase of the filtered induced electromotive force and the detected current can be a curve, a table, etc., and this application embodiment does not limit it.
[0062] refer to Figure 1 The first part of the primary winding 14 is wound on the main magnetic core 11, and the second part of the primary winding 14 is wound on the auxiliary magnetic core 12. The number of turns in the first part and the second part of the primary winding 14 can be the same.
[0063] The winding direction of the first part of the primary winding 14 is opposite to that of the second part of the primary winding 14. That is, the primary winding 14 is connected in reverse on the main magnetic core 11 and the auxiliary magnetic core 12 (which can be simply referred to as reverse connection).
[0064] Optionally, the first part of the secondary winding 15 is wound on the main magnetic core 11, and the second part of the secondary winding 15 is wound on the auxiliary magnetic core 12. The number of turns in the first part and the second part of the secondary winding 15 can be the same.
[0065] The winding direction of the first part of the secondary winding 15 is the same as the winding direction of the second part of the secondary winding 15.
[0066] For example, the excitation current of the primary winding 14 is represented by I1, the induced current of the secondary winding 15 is represented by I2, the number of turns of the first and second parts of the primary winding 14 is represented by N1, the number of turns of the secondary winding 15 is represented by N2, and the excitation current of the secondary winding 15 is represented by I... 02 express.
[0067] Without using the compensation module 2 to output the compensation current I3, according to the principle of magnetomotive force balance, the magnetomotive force balance equation of the main magnetic core 11 is:
[0068] I1N1+I2N2=I 01 N1
[0069] The magnetomotive force balance equation for auxiliary magnetic core 12 is:
[0070] I1N1+I2N2=I 02 N1
[0071] It can be seen that I 01 =I 02 .
[0072] With the compensation module 2 outputting the compensation current I3, according to the principle of magnetomotive force balance, the magnetomotive force balance equation of the main magnetic core 11 is:
[0073] I1N1+I′2N2=I′ 01 N1
[0074] Among them, I′ 01 I′2 represents the excitation current of the main magnetic core 11 after the introduction of compensation module 2, and I′2 represents the induced current of the secondary winding 15 after the introduction of compensation module 2, satisfying I′2=I2+I″2, where I″2 is used to represent the induced current generated by I3 on the secondary winding 15.
[0075] The magnetomotive force balance equation for auxiliary magnetic core 12 is:
[0076] I1N1+I′2N2+I3N3=I′ 02 N1
[0077] Where I3 represents the compensation current, N3 represents the number of turns in compensation winding 16, and I′ 02 This indicates the excitation current of the auxiliary magnetic core 12 after the introduction of compensation module 2.
[0078] Since the excitation current that establishes magnetic flux in the main magnetic core 11 is the main factor affecting the measurement error of the current sensor 10, it is necessary to compensate the excitation current as much as possible to achieve the zero magnetic flux state of the main magnetic core 11.
[0079] To make the magnetic flux of the main magnetic core 11 zero, the amplitude and phase of I″2 can be indirectly adjusted by adjusting I3, so that I′2N2=-I1N1. At this time, the magnetomotive force balance equation of the main magnetic core 11 becomes:
[0080] I' 01 N1 = 0
[0081] The magnetomotive force balance equation for auxiliary magnetic core 12 becomes:
[0082] I3N3=I0′2N1
[0083] It can be seen that after the introduction of compensation module 2, the excitation current I0′1 of the main magnetic core 11 is 0, that is, the magnetic flux of the main magnetic core 11 is 0, thus achieving the compensation effect of zero magnetic flux.
[0084] The induced electromotive force at different positions of the main magnetic core 11 can be obtained by multiple sampling windings 13 wound on the main magnetic core 11. According to the magnetic circuit theorem, the induced electromotive force of the nth sampling winding can be expressed as:
[0085]
[0086] Among them, e n N represents the measured value of the induced electromotive force of the nth sampling winding. 0n Φ represents the number of turns in the nth sampling winding. n Let dt represent the magnetic flux of a single turn of the nth sampling winding, and let dt represent the time derivative. This represents the flux change rate of the nth sampling winding.
[0087] The magnetic field strength, magnetic induction intensity, and magnetic flux of the nth sampling winding satisfy the following:
[0088] B n =μH n
[0089] Φ n =B n S n
[0090] Among them, H n B represents the magnetic field strength of the nth sampling winding. n S represents the magnetic flux density of the nth sampling winding, μ represents the permeability of the main magnetic core, and S represents the magnetic flux density of the nth sampling winding. n This represents the cross-sectional area of the nth sampling winding.
[0091] It can be observed that e n With H n Relevant. Assuming I1 is a sinusoidal AC signal, then the excitation current I of the primary winding 14 is... 01 It can be represented as:
[0092]
[0093] Among them, I 01m Indicate I 01 The peak value, ω represents I 01 angular frequency, Indicate I 01 The phase, t represents time.
[0094] According to the magnetic circuit theorem, we can obtain:
[0095] I 01 N1=Hl
[0096] Where H represents the magnetic field strength of the primary winding 14, and l represents the magnetic circuit length of the primary winding 14, when H n When H = , the measured value of the induced electromotive force of the nth sampling winding satisfies:
[0097]
[0098] In reality, H n This is not equal to H. Therefore, the measured value of the induced electromotive force of the nth sampling winding should be expressed as:
[0099]
[0100] Among them, e n N represents the measured value of the induced electromotive force of the nth sampling winding. 0n S represents the number of turns in the nth sampling winding. n Let l represent the cross-sectional area of the nth sampling winding. n N represents the magnetic path length of the nth sampling winding, N1 represents the number of turns of the primary winding wound on the main core / auxiliary core, and ω represents the angular frequency of the excitation current of the main core. I represents the phase of the excitation current of the main magnetic core. 01m The peak value of the excitation current of the main magnetic core is represented by t, where t represents time. Δe represents the calculated electromotive force at the nth sampling winding. n This represents the difference between the calculated electromotive force at the nth sampling winding and the measured induced electromotive force at the nth sampling winding.
[0101] It can be observed that e n Contains I 01m and The induced electromotive force at different positions on the main magnetic core 11 is obtained through multiple sampling windings 13. The amplitude and phase of each induced electromotive force are obtained by the amplitude and phase detection unit 21. The first processing unit 22 calculates the excitation current I of the primary winding 14 according to electromagnetic theory. 01 The control unit 23 is based on I 01The output compensation current I3 acts on the compensation winding 16. This current is then transmitted through the secondary winding 15 to I... 01 Compensation is performed, therefore, the induced electromotive force at different positions of the main magnetic core 11 may change. I is then recalculated based on the changed induced electromotive force at different positions of the main magnetic core 11. 01 And adjust the compensation current I3 until I 01 The current is zero or less than the preset current threshold. When the excitation current I1 of the primary winding 14 changes, the compensation module 2 can adaptively adjust the output compensation current I3 to I... 01 Dynamic compensation is performed.
[0102] In this embodiment, the main magnetic core 11 and the auxiliary magnetic core 12 are the same size and shape, both being ring-shaped or the like. Both the main magnetic core 11 and the auxiliary magnetic core 12 have an outer diameter of 100 mm, an inner diameter of 60 mm, and a height of 30 mm. They are both made of permalloy, which has high permeability, low coercivity, and good temperature stability, helping to reduce measurement errors and improve accuracy. Specifically, the high permeability enhances the concentration of the magnetic field, thereby improving the sensitivity of the current sensor 10; the low coercivity ensures good magnetic performance even under high-frequency conditions, reducing hysteresis loss; and the good temperature stability guarantees the consistency of measurement results under different ambient temperatures.
[0103] The primary winding 14 uses 0.5mm diameter insulated copper wire and has 100 turns. The secondary winding 15 has 40 turns. Multiple sampling windings 13 all use 0.35mm diameter insulated copper wire and have 20 turns each. The compensation winding 6 has the same number of turns as any of the sampling windings.
[0104] like Figure 4 As shown, under the same conditions with a single coil, when the magnetic induction intensity of the primary winding 14 is 0.538T, the magnetic induction intensity B at sampling point ④ is 0.478T, with an error of 0.06T. The magnetic induction intensity of the primary winding 14, calculated by fitting the magnetic induction intensities at different positions of the main magnetic core 11 obtained from sampling points ① to ⑦, is 0.534T, with an error of only 0.004T. It is evident that multiple sampling windings can significantly correct measurement errors, thereby effectively improving the detection accuracy of the current.
[0105] This application also provides an electronic device, including the aforementioned current sensor 10. Further details regarding this application will not be provided.
[0106] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of the claims of the present invention pending approval.
Claims
1. A current sensor based on multiple sampling windings, characterized in that, It includes a sensing module, a compensation module, and a processing module; wherein, the sensing module includes a main magnetic core, an auxiliary magnetic core, multiple sampling windings, a primary winding, a secondary winding, and a compensation winding; The primary winding is wound on the main magnetic core and the auxiliary magnetic core; the secondary winding is wound on the main magnetic core and the auxiliary magnetic core, and the secondary winding is connected to the processing module; the plurality of sampling windings are wound on the main magnetic core, and the plurality of sampling windings are all connected to the input terminal of the compensation module; the compensation winding is wound on the auxiliary magnetic core, and the compensation winding is connected to the output terminal of the compensation module.
2. The current sensor according to claim 1, characterized in that, The plurality of sampling windings are used to: acquire the induced electromotive force at different positions of the main magnetic core; The compensation module is used to: determine the excitation current of the primary winding based on the induced electromotive force at each position, and output a compensation current based on the excitation current of the primary winding; The compensation winding is used to: compensate the induced current of the secondary winding according to the compensation current; The secondary winding is used to: obtain the induced electromotive force of the secondary winding; The processing module is used to output a detection current based on the induced electromotive force of the secondary winding.
3. The current sensor according to claim 1, characterized in that, The compensation module includes an amplitude and phase detection unit, a first processing unit, and a control unit; The input terminal of the amplitude and phase detection unit is connected to the plurality of sampling windings, the output terminal of the amplitude and phase detection unit is connected to the input terminal of the first processing unit, the output terminal of the first processing unit is connected to the input terminal of the control unit, and the output terminal of the control unit is connected to the compensation winding.
4. The current sensor according to claim 3, characterized in that, The amplitude and phase detection unit is used to detect the amplitude and phase of the induced electromotive force at each position; The first processing unit is used to: determine the excitation current of the primary winding based on the amplitude and phase of the induced electromotive force at each position; The control unit is used to: perform proportional-integral-derivative control on the excitation current of the primary winding, and output a compensation current to the compensation winding.
5. The current sensor according to claim 1, characterized in that, The processing module includes an amplification unit, a filtering unit, a phase-sensitive detection unit, and a second processing unit; The input terminal of the amplification unit is connected to the secondary winding, the output terminal of the amplification unit is connected to the input terminal of the filter unit, the output terminal of the filter unit is connected to the input terminal of the phase-sensitive detector unit, the output terminal of the phase-sensitive detector unit is connected to the input terminal of the second processing unit, and the output terminal of the second processing unit is used to output the detection current.
6. The current sensor according to claim 5, characterized in that, The amplification unit is used to amplify the induced electromotive force of the secondary winding to obtain an amplified induced electromotive force. The filtering unit is used to: filter the amplified induced electromotive force to obtain the filtered induced electromotive force. The phase-sensitive detector unit is used to: rectify and phase-discriminate the filtered induced electromotive force to obtain the amplitude and phase of the filtered induced electromotive force; The second processing unit is used to: output the detection current based on the amplitude and phase of the filtered induced electromotive force, and in combination with the correspondence between the amplitude and phase of the filtered induced electromotive force and the detection current.
7. The current sensor according to claim 1, characterized in that, The measured value of the induced electromotive force of the sampling winding satisfies: Among them, e n N represents the measured value of the induced electromotive force of the nth sampling winding. 0n S represents the number of turns in the nth sampling winding. n Let l represent the cross-sectional area of the nth sampling winding. n N1 represents the magnetic path length of the nth sampling winding, N1 represents the number of turns of the primary winding wound on the main magnetic core / auxiliary magnetic core, and ω represents the angular frequency of the excitation current of the main magnetic core. I represents the phase of the excitation current of the main magnetic core. 01m The value represents the peak value of the excitation current of the main magnetic core, and t represents time. Δe represents the calculated electromotive force at the nth sampling winding. n This represents the difference between the calculated electromotive force at the nth sampling winding and the measured induced electromotive force at the nth sampling winding.
8. The current sensor according to claim 1, characterized in that, The first part of the primary winding is wound on the main magnetic core, and the second part of the primary winding is wound on the auxiliary magnetic core; The winding direction of the first part of the primary winding is opposite to the winding direction of the second part of the primary winding.
9. The current sensor according to claim 8, characterized in that, The first part of the secondary winding is wound on the main magnetic core, and the second part of the secondary winding is wound on the auxiliary magnetic core; The winding direction of the first part of the secondary winding is the same as the winding direction of the second part of the secondary winding.
10. An electronic device, characterized in that, Includes a current sensor as described in any one of claims 1 to 9.