A method for continuously detecting and analyzing the transverse magnetic property difference of an electrical steel coil online

Abstract

A kind of method for detecting and analyzing the transverse magnetic property difference of electrical steel coil in line continuously, the detection and analysis of real-time magnetic property of different parts in the width direction of strip are completed by the magnetic conductivity meter arranged in the width direction of strip;The magnetic conductivity meter includes: yoke, excitation coil wound in the middle of yoke, secondary coil wound in the end of yoke;The excitation coil is used to generate excitation magnetic field according to excitation power supply;Yoke is arranged in the mode of end facing strip, for forming approximate closed magnetic circuit with strip, to expand the excitation magnetic field generated by excitation coil, so that the induced electromotive force is generated in the approximate closed magnetic circuit of secondary coil, the signal of corresponding part of strip is characterized by the signal of secondary coil, and the magnetic property of corresponding part is obtained by capturing and calculating the signal.The method for detecting and analyzing the transverse magnetic property difference of electrical steel coil in line continuously of the application realizes the monitoring of real-time transverse magnetic property difference of strip full length.

Description

Technical Field

[0001] This invention belongs to the field of magnetic property measurement of electrical steel, specifically relating to a method for online continuous detection and analysis of differences in transverse magnetic properties of electrical steel coils. Background Technology

[0002] To adapt to the national green and low-carbon energy development strategy, the power industry's high requirements for the quality of electrical steel products are no longer limited to high performance levels and grade grades. For some high-end products, such as high-efficiency distribution transformers and ultra-high voltage transformers, the transverse properties of the strip steel are also crucial. Figure 1 As shown in the horizontal axis (A, B, C, ..., X), there are also clear requirements for the performance differences of different parts.

[0003] Current online magnetic property measurement technology can only measure and analyze the length direction of the strip. For measuring transverse performance differences, offline testing can only be performed by sampling from the beginning and end of the strip to obtain the transverse performance differences at the sampled locations. The direct drawback is that it can only obtain the differences at the sampled locations, not the differences of the entire roll; the indirect drawbacks include that sampling affects the production efficiency and yield of electrical steel, and the process is cumbersome and time-consuming.

[0004] Application CN201811544873.3 discloses "a monolithic permeameter, testing device, and testing method for performance testing of grain-oriented silicon steel sheets." The monolithic permeameter includes a U-shaped upper yoke, a U-shaped lower yoke, a primary coil winding, a secondary coil winding, an H-coil winding, and a support plate. The secondary coil windings are located inside the primary coil windings and are all arranged on the support plate. The test sample is placed on the support plate and located in the middle of the secondary coil windings. The H-coil windings are located below the middle portion of the lower surface of the test sample. The H-coil windings include 3 to 5 H-coil units of equal size, equally spaced, and arranged in series. All H-coil units are symmetrically distributed along the central axis of the test sample below the middle portion of the lower surface of the test sample. The application also provides a testing device and a testing method. The results obtained by directly measuring the magnetic polarization intensity of a monolithic sample of electrical steel strip using the H-coil windings and by using a testing method with digital air flux compensation are closer to the true value of the sample.

[0005] The invention application with application number CN202010839385.6 discloses "a continuous iron loss measuring device for electrical steel sheets". The device includes an inner frame, a cylinder, an outer frame, an induction coil, an excitation coil, an air flux compensation coil, and a magnetic field coil. The inner frame is supported and controlled by the cylinder and is movable up and down inside the outer frame. The induction coil is wound around the center of the outer frame and close to the outer frame. The excitation coil is fully wound on the outer frame and covers the induction coil. The air flux compensation coil is wound on the inner frame. The magnetic field coil is installed close to the air flux compensation coil and is located at the center above the inner frame. Summary of the Invention

[0006] To address the above problems, this invention provides a method for online continuous detection and analysis of differences in transverse magnetic properties of electrical steel coils, the specific technical solution of which is as follows:

[0007] A method for online continuous detection and analysis of differences in transverse magnetic properties of electrical steel coils, characterized in that:

[0008] Based on the set permeability meter, the real-time magnetic properties of different parts of the strip in the width direction are detected, and the online continuous transverse magnetic property difference of electrical steel coil is detected and analyzed.

[0009] The permeability meter includes: a magnetic yoke, an excitation coil wound around the middle of the magnetic yoke, and a secondary coil wound around the end of the magnetic yoke;

[0010] The excitation coil wound around the middle of the magnetic yoke is used to generate an excitation magnetic field according to the excitation power supply.

[0011] The magnetic yoke is positioned with its end facing the strip steel to form an approximately closed magnetic circuit with the strip steel, thereby expanding the excitation magnetic field generated by the excitation coil. This allows the secondary coil to generate an induced electromotive force within this approximately closed magnetic circuit.

[0012] The signal of the strip at the corresponding part is characterized by the signal of the secondary coil wound around the end of the yoke, and the magnetic properties of the corresponding part are obtained by capturing and calculating the signal.

[0013] A method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to the present invention is characterized in that:

[0014] The permeability gauges are three distributed along the width direction of the strip.

[0015] The yokes in each magnetometer are set at a distance greater than 20 mm from each other;

[0016] The two magnetic yokes at the edges are set at a distance greater than 20mm from the edges of their respective strips;

[0017] (The above settings are used to ensure signal integrity and interference resistance).

[0018] A method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to the present invention is characterized in that:

[0019] The aforementioned "capture of the signal" is achieved by establishing the excitation signal in series (this setting eliminates the influence caused by differences in signal sources) and by establishing the acquisition of their respective output signals in parallel.

[0020] A method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to the present invention is characterized in that:

[0021] The magnetic yokes in each permeameter used to detect the real-time magnetic properties of different parts of the strip in the width direction are composed of a set of symmetrically arranged upper and lower parts of the strip, with secondary coils symmetrically wound at the end of each magnetic yoke in the set.

[0022] Accordingly, the phrase "characterizing the signal of the strip at the corresponding part by the signal of the secondary coil wound around the end of the yoke" specifically means: calculating the average value of the signal of the secondary coil at each end of each yoke in each set of yokes, and using the result of the average value calculation to characterize the signal of the strip at that part.

[0023] A method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to the present invention is characterized in that:

[0024] A set of magnetic yokes is symmetrically arranged at the upper and lower parts of the strip, with the distance from the strip being equal to that of the strip.

[0025] A method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to the present invention is characterized in that:

[0026] The magnetic permeability meter is installed in a section of the strip length where support rollers are provided at both the front and rear.

[0027] A method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to the present invention is characterized in that:

[0028] The magnetic permeability meter is installed in a section of the strip length where support rollers are provided at both the front and rear ends along the strip length.

[0029] The distance between a set of magnetic yokes symmetrically arranged at the top and bottom of the strip and the strip is equal by adjusting the support rollers.

[0030] A method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to the present invention is characterized in that:

[0031] The span of the magnetic yoke is determined based on the speed of the steel coil and the frequency of the acquired signal.

[0032] A method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to the present invention is characterized in that:

[0033] The distance between the end of the magnetic yoke and the surface of the strip steel is set to be less than or equal to 200 mm.

[0034] A method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to the present invention is characterized in that:

[0035] The magnetic polarization intensity was calculated by capturing the induced electromotive force of the secondary coil wound around the end of the yoke, and a real-time characterization of the magnetic properties of different parts of the strip in the width direction was established.

[0036] A method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to the present invention is characterized in that:

[0037] The difference in transverse magnetic properties of the strip is characterized by calculating the difference in magnetic polarization intensity at different transverse positions compared to the center position.

[0038] The calculation of the difference in magnetic polarization intensity between different lateral positions and the center position is performed according to the following formula:

[0039]

[0040] In the above formula,

[0041] J x : Magnetic polarization intensity at different locations, unit: Tesla (T);

[0042] J c : Magnetic polarization intensity at the center, unit: Tesla (T).

[0043] A method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to the present invention is characterized in that:

[0044] The difference in transverse magnetic properties is characterized by the following formula:

[0045]

[0046] In the above formula,

[0047] Max(J1,J2,......,J N ): Maximum magnetic polarization at different locations across the entire plate width, in Tesla (T);

[0048] Min(J1,J2,......,J N ): Minimum magnetic polarization at different locations across the entire plate width, in Tesla (T);

[0049] Avg(J1,J2,......,J N ): Average magnetic polarization intensity across the entire plate, unit: Tesla (T).

[0050] A method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to the present invention is characterized in that:

[0051] By capturing the induced electromotive force of the secondary coil wound around the end of the yoke, the specific total loss is calculated, and a real-time characterization of the magnetic properties of different parts of the strip in the width direction is established.

[0052] A method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to the present invention is characterized in that:

[0053] The total loss is calculated according to the following formula (since it measures the difference between the individual losses, it is not necessary to calculate the actual value, so this formula is sufficient):

[0054]

[0055] In the above formula,

[0056] P s Total loss, unit: watt (W);

[0057] J(t): Magnetic polarization intensity, unit: Tesla (T);

[0058] dH(t): Differential of magnetic field strength, unit: amperes per meter (A / m);

[0059] ρ: Density, unit: kilograms per cubic meter (kg / m³) 3 ).

[0060] A method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to the present invention is characterized in that:

[0061] The difference in transverse magnetic properties of the strip is characterized by calculating the difference in total loss between different transverse positions and the center position.

[0062] The calculation of the difference in total loss between different lateral positions and the center position is performed according to the following formula:

[0063]

[0064] In the above formula,

[0065] P sx Total loss at different locations, unit: watts (W);

[0066] P sc Total loss at the center location, unit: watt (W).

[0067] A method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to the present invention is characterized in that:

[0068] The difference in transverse magnetic properties is characterized by the following formula:

[0069]

[0070] In the above formula,

[0071] Max(P s1 ,P s2 ,......,P sN ): Maximum specific total loss value at different parts of the entire plate width, unit: watts (W);

[0072] Min(P s1 ,P s2 ,......,P sN ): Minimum specific total loss value at different locations across the entire plate width, unit: watts (W);

[0073] Avg(P s1 ,P s2 ,......,P sN ): Average total loss of the entire plate as a percentage of its width, in watts (W).

[0074] This invention discloses a method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils. By winding a coil around a magnetic yoke and forming an approximately closed magnetic circuit with the yoke and the strip, the secondary coil wound at the yoke end generates an induced electromotive force under excitation because it is within the closed magnetic circuit. Simultaneously, by controlling the spacing between the yoke and the strip and the specific winding position of the secondary coil on the yoke, a characterization of the strip signal at the corresponding location is established through the signal from the secondary coil. Furthermore, to ensure stable and reliable signals, considerations are given to how to accurately represent signal values, the influence of strip fluctuations, and how to reduce interference between signals. Regarding more accurate signal value representation, the stability of the input signal and the reliability of the output signal are considered. A series excitation signal is established to ensure the stability and uniformity of the input signal. A symmetrical magnetic yoke is constructed, with secondary coils wound at the left and right ends of the yoke. The final output signal is then characterized by the average of the signals at the four positions (upper, lower, left, and right). To address the impact of strip fluctuations, the detection permeameter is placed in a strip section with support rollers at both ends. The support rollers are adjusted to straighten the strip in this section, ensuring equal distances from the upper and lower magnetic yokes. To reduce signal interference, the spacing between magnetic yokes and the distance between the edge magnetic yokes and the strip edge are rationally set. Magnetic properties in this invention are characterized by magnetic polarization intensity and / or specific total loss. Since only the difference in magnetic properties across the strip's transverse direction is measured, and the actual value is not required, the calculation of specific total loss does not rely on Epstein's square or complex fitting formulas; the calculation formula in this invention suffices. In summary, this invention provides a method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils. Through the internal structure of the permeameter and the consideration and setting of various external factors, it enables the acquisition and calculation of characterizable magnetic property signals at different locations along the strip's width, achieving real-time online monitoring of transverse magnetic property differences across the entire strip length. Attached Figure Description

[0075] Figure 1 Schematic diagram of different transverse parts of strip steel in existing technology;

[0076] Figure 2 This is a schematic diagram of the circuit connections during the working principle and process of the present invention;

[0077] Figure 3 for Figure 2 A simplified diagram;

[0078] Figure 4 This is a schematic diagram illustrating the installation position during the working principle and process of the present invention;

[0079] Figure 5 This is a schematic diagram of the single-sided magnetic yoke arrangement in the working principle and process of the present invention;

[0080] Figure 6 This is a schematic diagram illustrating the symmetrical arrangement of magnetic yokes on the upper and lower parts of the strip steel in the working principle and process of this invention.

[0081] Figure 7 This is a schematic diagram showing the overall installation of the detection device in the finished product annealing production line, illustrating the working principle and process of this invention. Detailed Implementation

[0082] The following is a detailed description of a method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to the present invention, based on the accompanying drawings and specific embodiments.

[0083] A method for online continuous detection and analysis of differences in transverse magnetic properties of electrical steel coils, characterized in that:

[0084] Based on the set permeability meter, the real-time magnetic properties of different parts of the strip in the width direction are detected, and the online continuous transverse magnetic property difference of electrical steel coil is detected and analyzed.

[0085] The permeability meter includes: a magnetic yoke, an excitation coil wound around the middle of the magnetic yoke, and a secondary coil wound around the end of the magnetic yoke;

[0086] The excitation coil wound around the middle of the magnetic yoke is used to generate an excitation magnetic field according to the excitation power supply.

[0087] The magnetic yoke is positioned with its end facing the strip steel to form an approximately closed magnetic circuit with the strip steel, thereby expanding the excitation magnetic field generated by the excitation coil. This allows the secondary coil to generate an induced electromotive force within this approximately closed magnetic circuit.

[0088] The signal of the strip at the corresponding part is characterized by the signal of the secondary coil wound around the end of the yoke, and the magnetic properties of the corresponding part are obtained by capturing and calculating the signal.

[0089] in,

[0090] The permeability gauges are three distributed along the width direction of the strip.

[0091] The yokes in each magnetometer are set at a distance greater than 20 mm from each other;

[0092] The two magnetic yokes at the edges are set at a distance greater than 20mm from the edges of their respective strips;

[0093] (The above settings are used to ensure signal integrity and interference resistance).

[0094] in,

[0095] The aforementioned "capture of the signal" is achieved by establishing the excitation signal in series (this setting eliminates the influence caused by differences in signal sources) and by establishing the acquisition of their respective output signals in parallel.

[0096] in,

[0097] The magnetic yokes in each permeameter used to detect the real-time magnetic properties of different parts of the strip in the width direction are composed of a set of symmetrically arranged upper and lower parts of the strip, with secondary coils symmetrically wound at the end of each magnetic yoke in the set.

[0098] Accordingly, the phrase "characterizing the signal of the strip at the corresponding part by the signal of the secondary coil wound around the end of the yoke" specifically means: calculating the average value of the signal of the secondary coil at each end of each yoke in each set of yokes, and using the result of the average value calculation to characterize the signal of the strip at that part.

[0099] in,

[0100] A set of magnetic yokes is symmetrically arranged at the upper and lower parts of the strip, with the distance from the strip being equal to that of the strip.

[0101] in,

[0102] The magnetic permeability meter is installed in a section of the strip length where support rollers are provided at both the front and rear.

[0103] in,

[0104] The magnetic permeability meter is installed in a section of the strip length where support rollers are provided at both the front and rear ends along the strip length.

[0105] The distance between a set of magnetic yokes symmetrically arranged at the top and bottom of the strip and the strip is equal by adjusting the support rollers.

[0106] in,

[0107] The span of the magnetic yoke is determined based on the speed of the steel coil and the frequency of the acquired signal.

[0108] in,

[0109] The distance between the end of the magnetic yoke and the surface of the strip steel is set to be less than or equal to 200 mm.

[0110] in,

[0111] The magnetic polarization intensity was calculated by capturing the induced electromotive force of the secondary coil wound around the end of the yoke, and a real-time characterization of the magnetic properties of different parts of the strip in the width direction was established.

[0112] in,

[0113] The difference in transverse magnetic properties of the strip is characterized by calculating the difference in magnetic polarization intensity at different transverse positions compared to the center position.

[0114] The calculation of the difference in magnetic polarization intensity between different lateral positions and the center position is performed according to the following formula:

[0115]

[0116] In the above formula,

[0117] J x : Magnetic polarization intensity at different locations, unit: Tesla (T);

[0118] J c : Magnetic polarization intensity at the center, unit: Tesla (T).

[0119] in,

[0120] The difference in transverse magnetic properties is characterized by the following formula:

[0121]

[0122] In the above formula,

[0123] Max(J1,J2,......,J N ): Maximum magnetic polarization at different locations across the entire plate width, in Tesla (T);

[0124] Min(J1,J2,......,J N ): Minimum magnetic polarization at different locations across the entire plate width, in Tesla (T);

[0125] Avg(J1,J2,......,J N ): Average magnetic polarization intensity across the entire plate, unit: Tesla (T).

[0126] in,

[0127] By capturing the induced electromotive force of the secondary coil wound around the end of the yoke, the specific total loss is calculated, and a real-time characterization of the magnetic properties of different parts of the strip in the width direction is established.

[0128] in,

[0129] The total loss is calculated according to the following formula (since it measures the difference between the individual losses, it is not necessary to calculate the actual value, so this formula is sufficient):

[0130]

[0131] In the above formula,

[0132] P s Total loss, unit: watt (W);

[0133] J(t): Magnetic polarization intensity, unit: Tesla (T);

[0134] dH(t): Differential of magnetic field strength, unit: amperes per meter (A / m);

[0135] ρ: Density, unit: kilograms per cubic meter (kg / m³) 3 ).

[0136] in,

[0137] The difference in transverse magnetic properties of the strip is characterized by calculating the difference in total loss between different transverse positions and the center position.

[0138] The calculation of the difference in total loss between different lateral positions and the center position is performed according to the following formula:

[0139]

[0140] In the above formula,

[0141] P sx Total loss at different locations, unit: watts (W);

[0142] P sc Total loss at the center location, unit: watt (W).

[0143] in,

[0144] The difference in transverse magnetic properties is characterized by the following formula:

[0145]

[0146] In the above formula,

[0147] Max(P s1 ,P s2 ,......,P sN ): Maximum specific total loss value at different parts of the entire plate width, unit: watts (W);

[0148] Min(P s1 ,P s2 ,......,P sN ): Minimum specific total loss value at different locations across the entire plate width, unit: watts (W);

[0149] Avg(P s1 ,P s2 ,......,P sN ): Average total loss of the entire plate as a percentage of its width, in watts (W).

[0150] Working principle and process

[0151] This technical solution aims to establish a method for online continuous analysis of the differences in transverse magnetic properties of electrical steel coils. It can measure and analyze the differences in transverse magnetic properties along the entire length of the electrical steel coil online. The following explanation can be understood in conjunction with... Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7 conduct.

[0152] like Figure 2 As shown, the assembled device includes a magnetometer, an excitation power supply, and a measurement host. The magnetometer consists of N (or more) sets of magnetic yokes, each set including an upper yoke and a lower yoke, arranged vertically opposite each other at the same position on the steel coil. The N (or more) sets of magnetic yokes are arranged laterally (including the sides and middle) of the electrical steel coil. Each set of yokes consists of upper and lower yokes, and each set of yokes is wound with one excitation winding and two secondary windings. The measurement host includes an excitation power supply, signal conditioning, a digital-to-analog converter, sampling resistors, a power amplifier, etc.

[0153] 1) Install the magnetometer:

[0154] The permeability meter 1 is installed at a position with support rollers 5 at both the front and rear to facilitate straightening of the electrical steel strip 4. The electrical steel strip 4 passes between the upper yoke 2 and the lower yoke 3 of the permeability meter 1. The support rollers 5 are adjusted so that the distance between the electrical steel strip 4 and the upper yoke 2 and the lower yoke 3 is approximately equal.

[0155] The distance d between the upper magnetic yokes 2 should be no less than 20mm, the distance δ between the upper magnetic yoke 2 and the edge of the electrical steel strip 4 should be no less than 20mm, and the distance t between the upper magnetic yoke 2 and the surface of the steel strip 4 should be no greater than 200mm. The lower magnetic yoke 3 is the same as the upper magnetic yoke 2.

[0156] Each upper yoke 2 has one set of excitation winding 6 and two sets of secondary windings 7 wound around it. The excitation winding 6 is located at the top of the upper yoke 2, and the two sets of secondary windings 7 are located at the two legs of the upper yoke 2 respectively. The lower yoke 3 is the same as the upper yoke 2.

[0157] 2) Device connection:

[0158] The excitation power supply connects the excitation windings 6 of N (3 or more) magnetic yokes (each group including one upper magnetic yoke 2 and one lower magnetic yoke 3) in series, and the secondary windings 7 of N (3 or more) magnetic yokes (each group including one upper magnetic yoke 2 and one lower magnetic yoke 3) in parallel to the measurement host.

[0159] 3) Measurement:

[0160] The required excitation current I for setting the magnetic polarization intensity is calculated according to formulas (1) and (2). The excitation current I output is adjusted and passed through the series-connected excitation winding 6 to excite the electrical steel strip 4. According to formulas (2) and (3), the induced voltages U1, U2, ..., U2 output from the secondary windings 7 of N groups (3 or more groups) of magnetic yokes (each group includes one upper magnetic yoke 2 and one lower magnetic yoke 3) are calculated. N Calculate the specific total loss P at different transverse positions of the corresponding electrical steel strip 4. s1 P s2 ... P sN .

[0161]

[0162]

[0163]

[0164] The required excitation current I for setting the magnetic field strength is calculated according to formula (1). The excitation current I is adjusted and output. It is then passed through the series-connected excitation winding 6 to excite the electrical steel strip 4. According to formula (2), the secondary induced voltages U1, U2, ..., U3 are output from the secondary windings 7 of N groups (3 or more groups) of magnetic yokes (each group includes one upper magnetic yoke 2 and one lower magnetic yoke 3). N Calculate the magnetic polarization intensities J1, J2, ..., J at different transverse positions of the corresponding electrical steel strip 4. N .

[0165] In Equation 1,

[0166] H(t): Magnetic field strength, unit: amperes per meter (A / m);

[0167] N1: Number of turns in the primary coil;

[0168] I(t): Excitation current, unit: Ampere (A);

[0169] l m Effective magnetic circuit length (equivalent magnetic circuit length), unit: meters (m).

[0170] In Equation 2,

[0171] J(t): Magnetic polarization intensity, unit: Tesla (T);

[0172] N2: Number of turns in the secondary coil;

[0173] A ε Cross-sectional area of ​​steel coil (strip), unit: square meters (m²) 2 );

[0174] U x(t): Secondary induced voltage, unit: volts (T);

[0175] μ: permeability, unit: Henry per meter (H / m);

[0176] H(t): Magnetic field strength, unit: amperes per meter (A / m).

[0177] In Equation 3,

[0178] P s Total loss, unit: watt (W);

[0179] J(t): Magnetic polarization intensity, unit: Tesla (T);

[0180] dH(t): Differential of magnetic field strength, unit: amperes per meter (A / m);

[0181] ρ: Density, unit: kilograms per cubic meter (kg / m³) 3 ).

[0182] 4) Analysis of differences in transverse magnetic properties

[0183] With the transverse center position P of the electrical steel strip 4 sc Based on the formula (4), the difference in total loss between different transverse positions and the middle position of the electrical steel strip 4 is calculated.

[0184] Among them, P sx The total loss at different locations (4)

[0185] Alternatively, according to formula (5), the ratio of the range of total loss at different locations to the average of total loss across the entire plate width can be used to evaluate the level of deviation of total loss in the transverse direction.

[0186]

[0187] Similarly, taking the transverse center position J of the electrical steel strip 4 as an example. c Based on the formula (6), the difference in magnetic polarization intensity at different transverse parts of the electrical steel strip 4 is calculated.

[0188] Among them, J x It represents the magnetic polarization intensity at different locations (6).

[0189] Alternatively, according to formula (7), the ratio of the range of magnetic polarization intensity at different locations to the average magnetic polarization intensity across the entire plate width can be used to evaluate the level of transverse magnetic polarization intensity deviation.

[0190]

[0191] 5) Online display of test results

[0192] The software interface enables continuous online monitoring of differences in magnetic properties at different parts of the strip, providing intuitive guidance for production.

[0193] This invention discloses a method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils. By winding a coil around a magnetic yoke and forming an approximately closed magnetic circuit with the yoke and the strip, the secondary coil wound at the yoke end generates an induced electromotive force under excitation because it is within the closed magnetic circuit. Simultaneously, by controlling the spacing between the yoke and the strip and the specific winding position of the secondary coil on the yoke, a characterization of the strip signal at the corresponding location is established through the signal from the secondary coil. Furthermore, to ensure stable and reliable signals, considerations are given to how to accurately represent signal values, the influence of strip fluctuations, and how to reduce interference between signals. Regarding more accurate signal value representation, the stability of the input signal and the reliability of the output signal are considered. A series excitation signal is established to ensure the stability and uniformity of the input signal. A symmetrical magnetic yoke is constructed, with secondary coils wound at the left and right ends of the yoke. The final output signal is then characterized by the average of the signals at the four positions (upper, lower, left, and right). To address the impact of strip fluctuations, the detection permeameter is placed in a strip section with support rollers at both ends. The support rollers are adjusted to straighten the strip in this section, ensuring equal distances from the upper and lower magnetic yokes. To reduce signal interference, the spacing between magnetic yokes and the distance between the edge magnetic yokes and the strip edge are rationally set. Magnetic properties in this invention are characterized by magnetic polarization intensity and / or specific total loss. Since only the difference in magnetic properties across the strip's transverse direction is measured, and the actual value is not required, the calculation of specific total loss does not rely on Epstein's square or complex fitting formulas; the calculation formula in this invention suffices. In summary, this invention provides a method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils. Through the internal structure of the permeameter and the consideration and setting of various external factors, it enables the acquisition and calculation of characterizable magnetic property signals at different locations along the strip's width, achieving real-time online monitoring of transverse magnetic property differences across the entire strip length.

Claims

1. A method for online continuous detection and analysis of differences in transverse magnetic properties of electrical steel coils, characterized in that: Based on the set permeability meter, the real-time magnetic properties of different parts of the strip in the width direction are detected, and the online continuous transverse magnetic property difference of electrical steel coil is detected and analyzed. The permeability meter includes: a magnetic yoke, an excitation coil wound around the middle of the magnetic yoke, and a secondary coil wound around the end of the magnetic yoke; The excitation coil wound around the middle of the magnetic yoke is used to generate an excitation magnetic field according to the excitation power supply. The magnetic yoke is arranged with its end facing the strip steel to form an approximately closed magnetic circuit with the strip steel, thereby expanding the excitation magnetic field generated by the excitation coil, so that the secondary coil is in the approximately closed magnetic circuit and generates an induced electromotive force. The signal of the strip at the corresponding part is characterized by the signal of the secondary coil wound around the end of the magnetic yoke, and the magnetic properties of the corresponding part are obtained by capturing and calculating the signal. The permeability gauges are three distributed along the width direction of the strip; The yokes in each magnetometer are set at a distance greater than 20 mm from each other; The two magnetic yokes at the edges are set at a distance greater than 20mm from the edges of their respective strips; The "capture of the signal" is achieved by establishing the excitation signal in series and acquiring the respective output signals in parallel. The magnetic yokes in each permeameter used to detect the real-time magnetic properties of different parts of the strip in the width direction are composed of a set of symmetrically arranged upper and lower parts of the strip, with secondary coils symmetrically wound at the end of each magnetic yoke in the set. Accordingly, the phrase "characterizing the signal of the strip at the corresponding part by the signal of the secondary coil wound around the end of the yoke" specifically means: calculating the average value of the signal of the secondary coil at each end of each yoke in each set of yokes, and using the result of the average value calculation to characterize the signal of the strip at that part. A set of magnetic yokes is symmetrically arranged at the upper and lower parts of the strip, with the distance from the strip being equal to that of the strip.

2. The method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to claim 1, characterized in that: The magnetic permeability meter is installed in a section of the strip length where support rollers are provided at both the front and rear.

3. The method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to claim 1, characterized in that: The magnetic permeability meter is installed in a section of the strip length where support rollers are provided at both the front and rear ends along the strip length direction; The distance between a set of magnetic yokes symmetrically arranged at the top and bottom of the strip and the strip is equal by adjusting the support rollers.

4. The method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to claim 1, characterized in that: The span of the magnetic yoke is determined based on the speed of the steel coil and the frequency of the acquired signal.

5. The method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to claim 1, characterized in that: The distance between the end of the magnetic yoke and the surface of the strip steel is set to be less than or equal to 200 mm.

6. The method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to claim 1, characterized in that: The magnetic polarization intensity was calculated by capturing the induced electromotive force of the secondary coil wound around the end of the yoke, and a real-time characterization of the magnetic properties of different parts of the strip in the width direction was established.

7. The method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to claim 6, characterized in that: The difference in transverse magnetic properties of the strip is characterized by calculating the difference in magnetic polarization intensity at different transverse positions compared to the center position. The calculation of the difference in magnetic polarization intensity between different lateral positions and the center position is performed according to the following formula: ， In the above formula, : Magnetic polarization intensity at different locations, unit: Tesla (T); : Magnetic polarization intensity at the center, unit: Tesla (T).

8. The method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to claim 6, characterized in that: The difference in transverse magnetic properties is characterized by the following formula: ， In the above formula, :Maximum magnetic polarization intensity at different locations across the entire plate width, unit: Tesla (T); Minimum magnetic polarization at different locations across the entire plate width, in Tesla (T). : Average magnetic polarization intensity across the entire plate, unit: Tesla (T).

9. The method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to claim 1, characterized in that: By capturing the induced electromotive force of the secondary coil wound around the end of the yoke, the specific total loss is calculated, and a real-time characterization of the magnetic properties of different parts of the strip in the width direction is established.

10. The method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to claim 9, characterized in that: The total loss is calculated using the following formula: ， In the above formula, : Total loss, unit: watt (W); : Magnetic polarization intensity, unit: Tesla (T); : The differential of magnetic field strength, unit: ampere per meter (A / m); Density, unit: kilograms per cubic meter (kg / m³) 3 ).

11. A method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to claim 9 or 10, characterized in that: The difference in transverse magnetic properties of the strip is characterized by calculating the difference in total loss between different transverse positions and the center position. The calculation of the difference in total loss between different lateral positions and the center position is performed according to the following formula: ， In the above formula, : Total loss at different locations, unit: watts (W). Total loss at the center location, unit: watt (W).

12. A method for online continuous detection and analysis of transverse magnetic property differences in electrical steel coils according to claim 9 or 10, characterized in that: The difference in transverse magnetic properties is characterized by the following formula: ， In the above formula, : Maximum specific total loss value at different parts of the entire plate width, unit: watts (W). Minimum specific total loss value at different parts of the entire plate width, unit: watts (W). : Average total loss of the entire plate as a percentage of width, in watts (W).

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