Method for measuring magnetic characteristic parameters of ferromagnetic material and related device

Abstract

The invention relates to the technical field of physical quantity measurement, in particular to a ferromagnetic material magnetic characteristic parameter measurement method and related device.The method comprises the steps that in the pulse excitation environment, the excitation current of an excitation coil and the capacitor voltage of an integrating capacitor are obtained; the effective cross sectional area, the integrating capacitance value, the integrating resistance value, the number of turns of a secondary winding, the number of turns of an excitation winding, the equivalent magnetic circuit length, the coil resistance of an excitation coil and the input instantaneous power of the sample piece to be measured are obtained; calculating the magnetic induction intensity according to the effective cross sectional area, the integral capacitance value, the integral resistance value, the number of turns of the secondary winding and the capacitance voltage; calculating the excitation magnetic field intensity according to the excitation current, the number of turns of the excitation winding and the equivalent magnetic circuit length; according to the exciting current, the coil resistance and the input instantaneous power, the magnetic core loss of the to-be-measured sample piece is calculated, and the technical problem that in the prior art, magnetic characteristic parameters of ferromagnetic materials under millisecond pulses are difficult to measure is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of physical quantity measurement, and in particular to a ferromagnetic material magnetic characteristic parameter measurement method and related device. BACKGROUND

[0002] Magnetic cores are one of the common main components of power equipment. In actual use, magnetic lines of force are gathered inside the magnetic cores to improve the magnetic permeability and increase the coupling between the winding coils. However, due to the limitation of the magnetic material used to make the magnetic cores, the high-frequency response capability of the magnetic cores is limited, and the magnetic cores are prone to saturation. With the increasing application of ferromagnetic materials in the field of pulse power, the application scenarios of the ferromagnetic materials cover multiple key fields such as high-power pulse power supply, electromagnetic launch, particle accelerator, radar system, and power electronic equipment. In the electromagnetic launch system, for example, the dynamic response performance of the magnetic cores is required to be more stringent in the Thompson coil launcher and the magnetic resistance coil launcher. For example, the working principle of the Thompson coil launcher is similar to that of the traditional induction coil gun. The armature of the Thompson coil launcher is made of a non-ferromagnetic conductor material, the guide structure is made of a ferromagnetic material, and the excitation coil is directly wound on the surface of the magnetic core. When the system is triggered, the magnetic core is rapidly magnetized, and the magnetic flux rises sharply, thereby inducing an eddy current in the armature, which is opposite to the direction of the current of the coil, so as to generate a strong electromagnetic thrust to accelerate the armature out of the magnetic core channel. The faster the change of the magnetic flux, the greater the induced current, and the stronger the thrust on the armature. Therefore, the magnetic cores are required to have high magnetic permeability, dynamic saturation performance, and response rate. At the same time, in order to reduce the large amount of eddy current loss generated in the pulse excitation process, the magnetic cores usually adopt a laminated structure, a magnetic powder compression molding, or a bundle-shaped magnetic core structure composed of multiple small magnetic rods to effectively suppress the circulating current path and reduce the heat loss and performance degradation caused by the eddy current.

[0003] The magnetic core material is usually a soft magnetic material such as silicon steel sheet, amorphous alloy, and nanocrystalline alloy. These materials can achieve low energy loss and high magnetic permeability under high-frequency magnetization conditions, thereby effectively improving the electromagnetic coupling efficiency from the primary winding to the secondary winding. In the millisecond pulse application, the magnetic core material not only needs to have excellent dynamic magnetic permeability and low hysteresis loss, but also needs to have good anti-eddy current capability to reduce the loss accumulation and temperature rise under the long-time wide pulse. In the pulse application environment, the commonly used magnetic core materials include ferromagnetic materials such as permalloy and high-performance silicon steel. These materials have significant differences in saturation characteristics, loss level, and dynamic response under pulse conditions.

[0004] However, current ferromagnetic material manufacturers usually only provide magnetic characteristic parameters under power frequency or low frequency conditions. These magnetic characteristic parameters are difficult to reflect the real working performance of the ferromagnetic materials under pulse conditions, thereby making it difficult to provide accurate data support for the structure design and performance prediction of the pulse magnetic elements, and easily leading to the performance of the pulse magnetic elements deviating from the design expectation in engineering practice. SUMMARY

[0005] The application provides a method for measuring magnetic characteristic parameters of ferromagnetic materials and a related device, and aims at solving the technical problem that the prior art cannot measure the magnetic characteristic parameters of ferromagnetic materials under millisecond pulses.

[0006] In one aspect, the application provides a method for measuring magnetic characteristic parameters of ferromagnetic materials, which is applied to a device for measuring magnetic characteristic parameters of ferromagnetic materials, the device comprising an excitation coil and a secondary coil which are coupled, and a sample to be measured arranged in the excitation coil and the secondary coil, and the secondary coil being connected in series with an integrating resistor and an integrating capacitor, and the method comprising the following steps.

[0007] In a pulse excitation environment, the excitation current of the excitation coil and the capacitor voltage of the integrating capacitor are obtained.

[0008] The effective cross-sectional area, the integrating capacitor value, the integrating resistor value, the number of turns of the secondary winding, the number of turns of the excitation winding, the equivalent magnetic path length, the coil resistance of the excitation coil and the input instantaneous power of the sample to be measured are obtained.

[0009] The magnetic induction intensity is calculated according to the effective cross-sectional area, the integrating capacitor value, the integrating resistor value, the number of turns of the secondary winding and the capacitor voltage.

[0010] The excitation magnetic field intensity is calculated according to the excitation current, the number of turns of the excitation winding and the equivalent magnetic path length.

[0011] The magnetic core loss of the sample to be measured is calculated according to the excitation current, the coil resistance and the input instantaneous power.

[0012] Optionally, the method further comprises the following steps.

[0013] The magnetization time of the sample to be measured is obtained, and the magnetic core loss power is obtained by dividing the magnetic core loss by the magnetization time.

[0014] Optionally, the method further comprises the following steps.

[0015] The effective volume of the magnetic core of the sample to be measured is obtained, and the magnetic core loss density is obtained by dividing the magnetic core loss by the effective volume of the magnetic core.

[0016] Optionally, the method further comprises the following steps.

[0017] The initial magnetization energy loss density is calculated according to the excitation magnetic field intensity and the magnetic induction intensity.

[0018] The eddy current and additional loss is calculated according to the magnetic core loss density and the initial magnetization energy loss density.

[0019] Optionally, the calculating the magnetic core loss of the sample to be measured according to the excitation current, the coil resistance and the input instantaneous power comprises:

[0020] integrating the product of the square of the excitation current and the coil resistance to obtain the excitation winding Joule loss;

[0021] subtracting the integrated input instantaneous power from the excitation winding Joule loss to obtain the magnetic core loss of the sample to be measured.

[0022] The application further provides an electronic device, which comprises a processor and a memory:

[0023] The memory is used for storing program codes and transmitting the program codes to the processor;

[0024] The processor is used for executing the method as described above according to the instructions in the program codes.

[0025] The application further provides a device for measuring magnetic characteristic parameters of ferromagnetic materials, which comprises an excitation coil and a secondary coil coupled, a current-voltage acquisition module and an electronic device as described above.

[0026] The sample to be measured is arranged in the excitation coil and the secondary coil, and the secondary coil is connected in series with an integrating resistor and an integrating capacitor.

[0027] The excitation coil is connected with a pulse current generating assembly.

[0028] The current-voltage acquisition module is connected with the electronic device and is used for acquiring the excitation current of the excitation coil and the capacitor voltage of the integrating capacitor.

[0029] Optionally, the pulse current generating assembly comprises a pulse power supply module.

[0030] The pulse power supply module is connected with both ends of the diode and is connected with both ends of the excitation coil through both ends of the diode.

[0031] A discharge switch is arranged at the connection between the pulse power supply module and the diode.

[0032] The discharge switch is connected with the discharge control unit.

[0033] Optionally, the pulse power supply module comprises a direct-current voltage regulating power supply and a pulse capacitor.

[0034] The direct-current voltage regulating power supply is connected with the pulse capacitor.

[0035] The pulse capacitor is connected with both ends of the diode and is connected with both ends of the excitation coil through both ends of the diode.

[0036] The discharge switch is arranged at the connection of the pulse capacitor and the diode.

[0037] Optionally, the number of the excitation coils is one or more; the connection mode of the multiple excitation coils is parallel or grouping.

[0038] The number of the pulse capacitors is one or more; the multiple pulse capacitors are connected in series or parallel.

[0039] The number of the freewheeling diodes is one or more, and the multiple diodes are connected in parallel.

[0040] From the above technical solutions, the present application has the following advantages:

[0041] The present application provides a kind of ferromagnetic material magnetic characteristic parameter measurement method, applied to ferromagnetic material magnetic characteristic parameter measurement device, the device includes coupling arrangement excitation coil and secondary coil;Excitation coil and secondary coil are provided with the sample piece to be measured, the secondary coil is connected in series with integrating resistance, integrating capacitor, the method includes: in the pulse excitation environment, the exciting current of the excitation coil, the capacitor voltage of the integrating capacitor is obtained;The effective cross-sectional area of the sample piece to be measured, integrating capacitance value, integrating resistance value, secondary winding number of turns, excitation winding number of turns, equivalent magnetic path length, coil resistance of excitation coil, input instantaneous power are obtained;According to the effective cross-sectional area, the integrating capacitance value, the integrating resistance value, the secondary winding number of turns and the capacitor voltage, calculate magnetic induction intensity;According to the exciting current, the excitation winding number of turns and the equivalent magnetic path length, calculate excitation magnetic field intensity;According to the exciting current, the coil resistance and the input instantaneous power, calculate the magnetic core loss of the sample piece to be measured.

[0042] The application provides a ferromagnetic material magnetic characteristic parameter measurement method, which comprises the following steps: obtaining excitation current of an excitation coil and capacitor voltage of an integral capacitor under pulse excitation, so as to realize measurement of magnetic characteristic parameters related to a sample to be measured under pulse working conditions and provide basic support for determining the magnetic characteristic parameters; and obtaining effective cross-sectional area of the sample to be measured, integral capacitor value, integral resistance value, secondary winding turns, excitation winding turns, equivalent magnetic path length, coil resistance of the excitation coil and input instantaneous power, calculating magnetic induction intensity according to the effective cross-sectional area, the integral capacitor value, the integral resistance value, the secondary winding turns and the capacitor voltage, and calculating excitation magnetic field intensity according to the excitation current, the excitation winding turns and the equivalent magnetic path length; calculating magnetic core loss of the sample to be measured according to the excitation current, the coil resistance and the input instantaneous power, so as to obtain magnetic characteristic parameters including the magnetic induction intensity, the excitation magnetic field intensity and the magnetic core loss, determine magnetic characteristics of the ferromagnetic material under different pulse working conditions based on the magnetic characteristic parameters, and solve the technical problem that the prior art is difficult to measure the magnetic characteristic parameters of the ferromagnetic material under millisecond pulse, so as to provide accurate and effective data support for structural design and performance prediction of a pulse magnetic element. BRIEF DESCRIPTION OF DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor under the premise of the drawings.

[0044] Figure 1 A structural schematic diagram of a ferromagnetic material magnetic characteristic parameter measurement device provided by the embodiment of the present application;

[0045] Figure 2 A connection relationship schematic diagram of the sample to be measured, the excitation coil and the secondary coil provided by the embodiment of the present application;

[0046] Figure 3 A structural schematic diagram of a discharge control unit provided by the embodiment of the present application;

[0047] Figure 4 A structural schematic diagram of a ferromagnetic material magnetic characteristic parameter measurement device provided by the embodiment of the present application;

[0048] Figure 5 A step flowchart of a ferromagnetic material magnetic characteristic parameter measurement method provided by the embodiment of the present application;

[0049] Figure 6Another step flow chart of a ferromagnetic material magnetic characteristic parameter measurement method provided by the embodiment of the application;

[0050] Figure 7 A use flow chart of a ferromagnetic material magnetic characteristic parameter measurement device provided by the application example of the application;

[0051] Figure 8 A measurement result graph of a ferromagnetic material magnetic characteristic parameter provided by the application example of the application. DETAILED DESCRIPTION

[0052] In pulse power technology, millisecond (ms) level pulses are widely used in energy storage, pulse magnetization, power electronic conversion, pulse plasma and special electromagnetic equipment fields. Compared with nanosecond (ns) level and microsecond (µs) level pulses, ms level pulses have longer electromagnetic energy transmission time, larger magnetic flux variation range and more significant magnetic hysteresis and eddy current effect. This puts higher requirements on the loss control ability, dynamic saturation characteristics and temperature rise stability of the magnetic core material. For example, in the high-voltage direct current circuit breaker in the power electronic field, the short-time pulse magnetization behavior directly affects the response speed and energy consumption level of the breaking process; and in electromagnetic launch scenes such as electromagnetic gun projectile launching, the magnetic field excited by the continuous pulse current acting on the conductor projectile can realize high-speed and high-stability acceleration launching. In order to select appropriate materials to make magnetic cores under pulse working conditions, the magnetic characteristics of various ferromagnetic materials need to be tested for pulse performance. Since the performance test of the magnetic core under the pulse current has high requirements on the measuring instrument and the excitation source, generally, material manufacturers do not have corresponding experimental equipment and the ability to measure the magnetization characteristics of ferromagnetic materials under various conditions, and cannot provide performance parameters of the magnetic core under pulse conditions, and users need to test the parameters of a specified material or structure size of the magnetic core according to actual needs.

[0053] Therefore, in order to improve the performance matching accuracy and design reliability of the magnetic element in the pulse power device, it is urgent to build a ferromagnetic material magnetization characteristic measurement method suitable for ms level pulse conditions, and to deeply study the dynamic magnetic response law, loss mechanism and thermal stability characteristics of the ferromagnetic material under the excitation of the pulse current, so as to provide a theoretical basis and experimental support for the design of an efficient, reliable and compact pulse electromagnetic system.

[0054] Therefore, in order to improve the performance matching accuracy and design reliability of the magnetic element in the pulse power device, it is urgent to build a ferromagnetic material magnetization characteristic measurement method suitable for ms level pulse conditions, and to deeply study the dynamic magnetic response law, loss mechanism and thermal stability characteristics of the ferromagnetic material under the excitation of the pulse current, so as to provide a theoretical basis and experimental support for the design of an efficient, reliable and compact pulse electromagnetic system.

[0055] Therefore, in order to improve the performance matching accuracy and design reliability of the magnetic element in the pulse power device, it is urgent to build a ferromagnetic material magnetization characteristic measurement method suitable for ms level pulse conditions, and to deeply study the dynamic magnetic response law, loss mechanism and thermal stability characteristics of the ferromagnetic material under the excitation of the pulse current, so as to provide a theoretical basis and experimental support for the design of an efficient, reliable and compact pulse electromagnetic system.

[0056] In order to make the application purposes, features and advantages of the present application more obvious and easy to understand, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings of the embodiments of the present application. Obviously, the embodiments described below are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0057] The electronic device provided by the embodiment of the present application comprises a processor and a memory.

[0058] The memory is configured to store program code and transmit the program code to the processor.

[0059] The processor is configured to execute the method for measuring the magnetic characteristic parameters of a ferromagnetic material according to the instructions in the program code.

[0060] Please refer to Figure 1 The embodiment of the present application provides a device for measuring the magnetic characteristic parameters of a ferromagnetic material, which comprises an excitation coil N1 and a secondary coil N2, a current and voltage acquisition module, and an electronic device 1 as described above; a sample to be measured is arranged in the excitation coil N1 and the secondary coil N2; the secondary coil N2 is connected in series with an integrating resistor R2 and an integrating capacitor C; the excitation coil N1 is connected with a pulse current generating assembly 3; the current and voltage acquisition module is connected with the electronic device 1 and is configured to acquire the excitation current of the excitation coil N1 and the capacitor voltage of the integrating capacitor C.

[0061] It should be noted that the sample to be measured refers to a ferromagnetic material that needs to be measured for the magnetic characteristic parameters, which can be a sheet silicon steel sheet, a ring-shaped sample or a standard-shaped sample made of other ferromagnetic materials. The standard-shaped sample refers to a sample that is processed according to the magnetic material test specification (a standardized method for measuring the characteristics of magnetic materials in the country or internationally), has a regular geometric size and is easy to place in a test coil, and its common forms include: a sheet sample cut into a rectangular or strip shape from a silicon steel sheet, a ring-shaped sample formed by overall processing or winding of a ferromagnetic material, and other regular geometric samples such as a square, a cylindrical or a C-shaped sample.

[0062] Before the test, the sample to be measured is arranged in the excitation coil N1 and the secondary coil N2. In one example, as shown in FIG. Figure 2 (a), which shows the structural relationship between the sample to be measured and the excitation coil N1 and the secondary coil N2 when the sample to be measured is a ring-shaped sample, wherein the excitation coil winding and the secondary coil winding are wound on the ring-shaped sample, R1 is a sampling resistor, U R1is the voltage of the sampling resistor, I1 is the current of the sampling resistor, C is the integrating capacitor C, Uc is the capacitor voltage of the integrating capacitor C, R2 is the integrating resistor, and I2 is the current of the integrating resistor R2. In another example, as shown in Figure 2 (b) shows the structural relationship between the test sample and the excitation coil N1 and the secondary coil N2 when the test sample is an electrical steel sheet sample, Figure 2 In the figure, the sample is the test sample, and the excitation and induction windings are the excitation coil winding and the induction coil winding. The test sample is arranged in the excitation coil winding and the induction coil winding.

[0063] In this embodiment, the pulse current generating assembly 3 is used to provide a pulse excitation current for the excitation coil N1, and the excitation coil N1 is used to generate an excitation signal applied to the test sample, so that the test sample is magnetized. The secondary coil N2 is used to induce the change of the magnetic flux in the test sample, and generate an induced electromotive force (i.e. an induced voltage signal). The integrating capacitor C and the integrating resistor R2 form an integrating module, which is used to integrate the induced voltage signal obtained by the secondary coil N2, so as to calculate the magnetic flux density and obtain the curve reflecting the change of the magnetic induction intensity in the magnetization process of the sample. In one example, the integration time constant of the integrating module is 10 times or more of the pulse width.

[0064] The current-voltage acquisition module includes a current acquisition unit 21 and a voltage acquisition unit 22. The current acquisition unit 21 is used to acquire the excitation current of the excitation coil N1, and the voltage acquisition unit 22 is used to acquire the capacitor voltage of the integrating capacitor C.

[0065] The current-voltage acquisition module and the electronic device 1 constitute a data acquisition and analysis system.

[0066] In one embodiment, the current acquisition unit 21 can be a current sensor or a Rogowski coil, or other devices that can realize current acquisition. The voltage acquisition unit 22 can be a voltage transformer or an oscilloscope and a voltage probe, or other devices that can realize voltage acquisition.

[0067] In one embodiment, the pulse current generating assembly 3 includes a pulse power supply module 4

[0068] The pulse power supply module 4 is connected across the diode D, and is connected across the excitation coil N1 through the diode D;

[0069] The connection between the pulse power supply module 4 and the diode D is provided with a discharge switch K.

[0070] The discharge switch K is connected with a discharge control unit 32.

[0071] It should be noted that the pulse power supply module 4 is used to generate excitation current through discharge for the excitation coil N1, so as to simulate the working condition of the actual pulse power device. The diode D plays a role of freewheeling in the whole loop. The discharge switch K is connected in series with the excitation coil N1, and is used to realize on-off control of the excitation current under the action of a control signal. The discharge control unit 32 is connected to the control end of the discharge switch K, and provides a control signal for the discharge switch K, so as to control the on-off of the discharge switch K. When the discharge switch K is closed, the loop is turned on, and the excitation coil N1 obtains the excitation current. When the discharge switch K is opened, the loop is turned off, and the excitation coil N1 loses power.

[0072] In the formula, the timing and duty cycle of the discharge switch K can be adjusted to adapt to the test requirements of different pulse widths and frequencies.

[0073] In one embodiment, the discharge control unit 32 includes a discharge control switch 321, a control chip 322, an optical coupler and the like components, as shown in the figure. Figure 3 As shown in the figure, the discharge control switch 321 is connected with the control chip 322, and the control chip 322 is connected with the optical coupler respectively.

[0074] It should be noted that the function of the optical coupler is to effectively isolate the high-voltage and low-voltage circuits, protect the control circuit from high-voltage impact, and at the same time ensure the stability of signal transmission. The optical coupler can effectively reduce electromagnetic interference (EMI), prevent electromagnetic wave radiation caused by high-frequency switching operation, and ensure the stability of the whole magnetic characteristic test system and the accuracy of the measurement data.

[0075] The working principle of the embodiment is that the discharge control switch 321 outputs a discharge signal, and after receiving the discharge signal, the control chip 322 of the discharge control unit 32 immediately sends a control signal to the discharge switch K to start the whole discharge process. In order to ensure reliable transmission and isolation of the signal, the control signal is first subjected to signal isolation through the optical coupler to avoid noise interference or signal transmission problems caused by direct electrical connection. Subsequently, the control signal after the optical coupler isolation is transmitted to the discharge switch K to control the on-off of the discharge switch K. It can be understood that the control signal in the control chip 322 can be changed and adjusted through the program. In one example, the control signal is a high-low level signal.

[0076] Therefore, the discharge control unit 32 in the embodiment can realize efficient, stable and low-interference control of the switch, and improve the performance and reliability of the pulse excitation system.

[0077] In one embodiment, the number of optical couplers can be determined according to actual measurement requirements.

[0078] In one embodiment, the pulse power supply module 4 includes a direct-current voltage regulating power supply 311 and a pulse capacitor 312.

[0079] The direct-current voltage regulator 311 is connected with the pulse capacitor 312;

[0080] The pulse capacitor 312 is connected with both ends of the diode D, and is connected with both ends of the excitation coil N1 through both ends of the diode D.

[0081] The discharge switch K is arranged at the connection between the pulse capacitor 312 and the diode D.

[0082] It should be noted that the direct-current voltage regulator 311 is used for supplying power to the entire measuring device and charging the pulse capacitor 312. The positive pole of the pulse capacitor 312 is connected to the input end of the discharge switch K, which is used for storing and releasing pulse energy. The output end of the discharge switch K is connected to the cathode of the diode D and one end of the excitation coil N1, which is used for supplying power to the excitation coil N1. The anode of the diode D and the other end of the excitation coil N1 are commonly connected to the negative pole of the capacitor bank, forming a complete loop, which ensures that the system can work normally and measure the pulse magnetization characteristics of the ferromagnetic material.

[0083] In one embodiment, the number of the excitation coil N1 is one or more; the connection mode of the plurality of excitation coils N1 is parallel or grouping;

[0084] The number of the pulse capacitor 312 is one or more; the plurality of pulse capacitors 312 are connected in series or parallel;

[0085] The number of the diode D is one or more, and the plurality of diodes D are connected in parallel.

[0086] It should be noted that the diode D is determined according to the test requirement, and the number thereof is one or more when being installed, which is used for freewheeling protection. The number of the excitation coil N1, the pulse capacitor 312 and the discharge switch K can be determined according to the actual test requirement. In addition, the capacity and the charging voltage amplitude of the pulse capacitor 312 can be adjusted according to the test requirement, so as to realize pulse discharge with different times, different interval times and different voltage amplitudes, so as to simulate the working characteristics of the ferromagnetic material under different working conditions.

[0087] In one embodiment, the electronic device 1 can be a host computer.

[0088] It should be noted that the host computer includes a software tool for receiving and processing current-voltage data, which can perform data analysis, graphical visualization and Fourier transform processing, and improve the accurate analysis of the magnetization characteristics of the magnetic material.

[0089] In one application example, the use process of the measuring device provided by the embodiment of the application can include:

[0090] Step S1: connect the pulse capacitor 312 to the DC voltage regulator 311, set the output voltage of the DC voltage regulator 311 according to the test requirements, connect the excitation coil N1 with the discharge switch K, and determine whether to install the diode D for freewheeling according to the test requirements, set the control timing and duty cycle of the discharge control unit 32 to the discharge switch K, and place the sample to be tested in the coil.

[0091] Step S2: the DC voltage regulator 311 charges the pulse capacitor 312, after charging, the discharge control unit 32 sends a control signal to the discharge switch K, the pulse power module 4 discharges the excitation coil N1, generates a pulse current, and measures the pulse current through the current sensor.

[0092] Step S3: the pulse current generates a magnetic field in the excitation coil N1, the sample to be tested is magnetized, the secondary coil N2 generates an induced voltage signal, the integration module integrates the induced voltage, and the voltage sensor measures the integrated signal.

[0093] Step S4: the host computer analyzes the collected current and voltage signals, calculates the magnetic field strength through the current signal measured by the current sensor, calculates the magnetic induction strength through the voltage on the capacitor in the integration circuit, and calculates the core loss by integrating the input voltage and current instantaneous power and subtracting the Joule loss of the excitation winding, to accurately characterize the magnetic properties of the ferromagnetic material under different pulse working conditions.

[0094] The ferromagnetic material magnetic property parameter measuring device provided by the embodiment of the application can measure the magnetic property parameters of the ferromagnetic material under single or multiple continuous pulse working conditions, the pulse excitation times, excitation voltage, pulse excitation amplitude and excitation interval are adjustable, the magnetic property of the ferromagnetic material can be tested and evaluated under different pulse working conditions, the theoretical support and experimental basis are provided for the optimal design of the magnetic core, the actual working conditions of the pulse power equipment are more in line with, and the engineering applicability of the test results is improved.

[0095] The above is the description of the ferromagnetic material magnetic property parameter measuring device provided by the embodiment of the application, and the following is the description of the ferromagnetic material magnetic property parameter measuring method provided by the embodiment of the application.

[0096] Please refer to Figure 5 The ferromagnetic material magnetic property parameter measuring method provided by the application comprises the following steps:

[0097] 101. In the pulse excitation environment, the excitation current of the excitation coil and the capacitance voltage of the integration capacitor are obtained.

[0098] It should be noted that the pulse excitation environment refers to that the excitation coil can normally obtain the millisecond pulse current provided by the pulse capacitor. The excitation current is the current in the excitation coil.

[0099] 102, obtain the effective cross-sectional area of the sample to be measured, the integral capacitance value, the integral resistance value, the number of turns of the secondary winding, the number of turns of the excitation winding, the equivalent magnetic circuit length, the coil resistance of the excitation coil, and the input instantaneous power.

[0100] It should be noted that the input instantaneous power is calculated by the input voltage and the input current. The input voltage refers to the instantaneous voltage applied to the input end of the excitation coil N1, and the input current refers to the instantaneous current flowing into the excitation coil N1 (i.e. the excitation current of the excitation coil). The coil resistance of the excitation coil refers to the DC resistance of the excitation coil N1, i.e. the resistance value measured under steady-state DC.

[0101] The effective cross-sectional area of the sample to be measured is determined according to the voltage amplitude of the excitation system, the number of turns of the secondary winding, the parameters of the integral module, and the desired measurement range. If the effective cross-sectional area is too small, the sample to be measured will enter the saturation state too early, losing the magnetic characteristic information in the low magnetic field region; if the effective cross-sectional area is too large, the induced signal will be too weak, the integral voltage output will be insufficient, and the measurement accuracy will be affected. To avoid the sample to be measured from entering the saturation state at the initial stage of excitation, causing the test curve to be distorted or unable to capture the response in the low magnetic induction region, the effective cross-sectional area of the sample to be measured should be reasonably set based on considering factors such as the excitation voltage amplitude, the pulse duration, the number of turns of the secondary coil, and the maximum allowable magnetic induction intensity of the sample to be measured, to ensure that the magnetic induction intensity does not exceed the saturation value during the measurement process, and the integral voltage is within the response range of the acquisition system.

[0102] Specifically, to ensure measurement accuracy and linear response, the minimum effective cross-sectional area should be back calculated according to the target maximum magnetic induction intensity and the characteristics of the integral module, and a margin should be reserved. In one example, the effective cross-sectional area S is determined according to the following formula:

[0103] (1)

[0104] In the formula, R2 is the integral resistance value, C is the integral capacitance value, Uc is the capacitor voltage of the integral capacitor, N2 is the number of turns of the secondary winding, B max is the target maximum saturation magnetic induction intensity of the sample to be measured.

[0105] 103, calculate the magnetic induction intensity according to the effective cross-sectional area, the integral capacitance value, the integral resistance value, the number of turns of the secondary winding, and the capacitor voltage.

[0106] It should be noted that in this step, the magnetic induction intensity is calculated using the effective cross-sectional area, the integral capacitance value, the integral resistance value, the number of turns of the secondary winding, and the capacitor voltage.

[0107] Wherein, the formula for calculating the magnetic induction intensity is:

[0108] (2)

[0109] In the formula, R2 is the integral resistance value, C is the integral capacitance value, Uc is the capacitor voltage of the integral capacitor, N2 is the number of turns of the secondary winding, and S is the effective cross-sectional area of the sample to be measured.

[0110] 104. Calculate the excitation magnetic field intensity according to the excitation current, the number of turns of the excitation winding, and the equivalent magnetic path length.

[0111] It should be noted that the excitation magnetic field intensity is calculated according to the excitation current, the number of turns of the excitation winding, and the equivalent magnetic path length. The formula for calculating the excitation magnetic field intensity is:

[0112] (3)

[0113] In the formula, N1 is the number of turns of the excitation winding, i is the excitation current, and L is the equivalent magnetic path length.

[0114] 105. Calculate the magnetic core loss of the sample to be measured according to the excitation current, the coil resistance, and the input instantaneous power.

[0115] It should be noted that the magnetic core loss refers to the magnetic core magnetization energy loss.

[0116] This step calculates the excitation winding Joule loss using the excitation current and the coil resistance based on the Joule law. The magnetic core loss of the sample to be measured is calculated according to the excitation winding Joule loss and the input instantaneous power.

[0117] In one embodiment, step 105 specifically includes the following sub-steps:

[0118] S51. Integrate the product of the square of the excitation current and the coil resistance to obtain the excitation winding Joule loss.

[0119] It should be noted that the winding resistance energy loss W R is:

[0120] (4)

[0121] In the formula, R is the coil resistance, N is the number of initial magnetization curve sampling points, i is the excitation current, k is the sampling point, is the sampling time interval.

[0122] S52. Subtract the integrated input instantaneous power from the excitation winding Joule loss to obtain the magnetic core loss of the sample to be measured.

[0123] It should be noted that based on S51, the magnetic core loss E loss That is, equal to the integral of the input voltage and current instantaneous power ui minus the excitation winding Joule loss W R Its expression is:

[0124] (5)

[0125] T is the sampling time.

[0126] The measurement method provided in the embodiment of the application, by obtaining the excitation current of the excitation coil and the capacitor voltage of the integration capacitor in the pulse excitation environment, realizes the measurement of the magnetic characteristic parameters related to the measured sample in the pulse working condition, and provides basic support for determining the magnetic characteristic parameters; and by obtaining the effective cross-sectional area of the measured sample, the integration capacitance value, the integration resistance value, the number of turns of the secondary winding, the number of turns of the excitation winding, the equivalent magnetic path length, the coil resistance of the excitation coil, and the input instantaneous power, the magnetic induction intensity is calculated according to the effective cross-sectional area, the integration capacitance value, the integration resistance value, the number of turns of the secondary winding and the capacitor voltage, and the excitation magnetic field intensity is calculated according to the excitation current, the number of turns of the excitation winding and the equivalent magnetic path length; the magnetic core loss of the measured sample is calculated according to the excitation current, the coil resistance and the input instantaneous power, so as to obtain the magnetic characteristic parameters including the magnetic induction intensity, the excitation magnetic field intensity and the magnetic core loss, determine the magnetic characteristics of the ferromagnetic material under different pulse working conditions based on the magnetic characteristic parameters, and solve the technical problem that the magnetic characteristic parameters of the ferromagnetic material under the millisecond pulse are difficult to measure in the prior art, thereby providing accurate and effective data support for the structural design and performance prediction of the pulse magnetic element.

[0127] It can be understood that steps 101 and 102 can be performed simultaneously or sequentially, and steps 102, 104 and 105 can be performed simultaneously or sequentially.

[0128] Please refer to Figure 6 On the basis of containing the above method embodiment, the ferromagnetic material magnetic characteristic parameter measurement method provided in the embodiment of the application further comprises:

[0129] 201, obtain the magnetization time of the measured sample, and divide the magnetic loss by the magnetization time to obtain the magnetic core loss power.

[0130] It should be noted that the excitation coil outputs an excitation signal to the measured sample, so that the measured sample is magnetized, and the magnetization time of the measured sample in this step is the time when the measured sample is magnetized.

[0131] Wherein, the expression of the magnetic core loss power is:

[0132] (6)

[0133] In the formula, Ploss E is the core loss power, loss E is the core loss, T is the magnetization time.

[0134] 202, obtain the effective volume of the core of the sample to be measured, divide the core loss by the effective volume of the core to obtain the core loss density.

[0135] It should be noted that the expression of the core loss density is:

[0136] (7)

[0137] In the formula, V r E is the effective volume of the core, W loss E is the core loss density.

[0138] 203, calculate the initial magnetization energy loss density according to the excitation magnetic field strength and the magnetic induction strength.

[0139] It should be noted that during the initial magnetization process, the area enclosed by the initial magnetization curve and the longitudinal axis is the initial magnetization energy loss of the unit effective volume core, that is, the initial magnetization energy loss density W i The calculation formula is:

[0140] (8)

[0141] 204, calculate the eddy current and additional loss according to the core loss density and the initial magnetization energy loss density.

[0142] It should be noted that the calculation formula of the eddy current and additional loss is:

[0143] (9)

[0144] In the formula, W loss E is the core loss density, W i E is the initial magnetization energy loss density, W E E is the eddy current and additional loss.

[0145] In the embodiment, the magnetic core loss power is obtained by dividing the magnetic loss by the magnetization time, the magnetic core effective volume of the sample to be measured is obtained, the magnetic core loss density is obtained by dividing the magnetic core loss by the magnetic core effective volume, the initial magnetization energy loss density is calculated according to the excitation magnetic field intensity and the magnetic induction intensity, the eddy current and additional loss is calculated according to the magnetic core loss density and the initial magnetization energy loss density, and thus the magnetic core loss power, the magnetic core loss density and the eddy current and additional loss are further obtained as the magnetic characteristic parameters of the sample to be measured on the basis of the magnetic induction intensity, the excitation magnetic field intensity and the magnetic core loss, so that more abundant magnetic characteristic parameters are provided, the technical problem that the magnetic characteristic parameters of the ferromagnetic material under the millisecond pulse are difficult to measure in the prior art is solved, and accurate and effective data support is provided for the structural design and performance prediction of the pulse magnetic element.

[0146] It should be understood that, although Figure 6 The steps in the flowchart shown are displayed in sequence according to the arrows, but these steps are not necessarily executed in sequence according to the arrows. Unless otherwise specified herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other sequences. Moreover, Figure 6 At least part of the steps in the flowchart can include multiple sub-steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of the sub-steps or stages is not necessarily sequential, but can be executed in rotation or alternation with at least part of other steps or sub-steps or stages of other steps.

[0147] In one application example, the ferromagnetic material magnetic characteristic parameter measurement method and device provided by the present application will be described in combination with a specific example.

[0148] The application example uses a silicon steel sheet with a single piece length of 300 mm and a width of 30 mm to lap the sample. The total number of pieces of the built sample is 100. The application example uses three excitation coils, which are uniformly wound and connected in parallel. The wire used for the three excitation coils is 1 mm enameled copper wire, and each excitation coil is wound 100 turns. The wire used for the secondary coil is 0.2 mm enameled copper wire, and the number of turns is 100. The number of pulse capacitors is three, and they are connected in parallel to the voltage output port of the DC voltage regulator to form a capacitor bank. The pulse capacitor used in the application example is a high-voltage energy storage capacitor, which has a low equivalent series resistance, can reduce energy loss during charging and discharging, and improve overall charging and discharging efficiency. In addition, high-voltage energy storage capacitors usually have high pulse resistance and fast discharge characteristics, which can maintain low loss under millisecond pulse excitation conditions, while ensuring high stability and high repeatability of the pulse current source, thereby meeting the test requirements of the pulse magnetization characteristics of the ferromagnetic material. Specifically, the pulse capacitor used in the application example has a withstand voltage of 450 V, a capacity of 1 mF for a single pulse capacitor, and an output voltage adjustable range of the DC voltage regulator of 0-450 V. The number of input and output ports of the control chip used in the application example is 37, and the output voltage range of the optocoupler used is 15-30 V, and the peak output current is 1 A. In the application example, the number of optocouplers is three, as shown in Figure 3 The specific steps of the method are as follows:

[0149] The use process of the ferromagnetic material magnetic property parameter measuring device is as shown in Figure 7 The specific steps of the method are as follows:

[0150] Before starting, place the sample to be tested in the excitation coil and the secondary coil to ensure that the sample can accept pulse magnetization, then connect the pulse current generating assembly according to the relationship as shown in Figure 1 、 Figure 2 、 Figure 4 Connect the excitation coil with the discharge switch, use a diode for freewheeling, and build the connection of the pulse capacitor, the discharge switch, the discharge control unit, and the DC voltage regulator. The application example can also be connected to the grounding device as needed. The application example sets the control timing of the control chip in the discharge control unit through the upper computer to ensure the stability and controllability of the pulse signal and the accuracy and repeatability of the pulse excitation.

[0151] After starting, according to the pre-tested voltage level, the output voltage value of the DC voltage regulating power supply is set and adjusted to ensure the stability and safety of the pulse test. The voltage output by the adjusted DC voltage regulating power supply charges the capacitor bank to provide sufficient energy reserve, and waits for the discharge signal.

[0152] When receiving the discharge signal output by the discharge control switch, the control chip of the discharge control unit immediately sends a control signal to the discharge switch to close the discharge switch and start the entire discharge process, so that the pulse capacitor bank discharges for the exciting coil. In order to ensure reliable transmission and isolation of signals, ensure reliable driving and synchronous control of switches, reduce power loss and electromagnetic interference, such as Figures 3-4 As shown in

[0153] The oscilloscope and the Rogowski coil are used to measure the exciting current, wherein three Rogowski coils are used to measure the current in the three exciting coils to obtain current data and calculate the magnetic field strength; the voltage probe is used to measure the voltage across the integrating capacitor to obtain the magnetic flux density of the measured sample, and a high-precision differential measurement method is used to reduce measurement error. The current and voltage signals collected by the upper computer are analyzed to extract the change rule of the magnetic hysteresis characteristics and loss characteristics of the material. The data analysis process includes Fourier transform processing to separate harmonic components and improve the accuracy of magnetic core loss calculation. The exciting magnetic field strength is calculated by the current signal measured by the Rogowski coil, the magnetic induction intensity is obtained by measuring the voltage on the capacitor in the integrating circuit, and the magnetic core loss is calculated by integrating the input voltage and current instantaneous power and subtracting the Joule loss of the exciting winding to accurately represent the magnetic properties of the ferromagnetic material under multiple continuous pulse working conditions.

[0154] As shown in Figure 8 As shown in Figure 8 The curves of the exciting magnetic field strength H and the magnetic induction intensity B changing with time when the magnetic voltage is 100V and the pulse interval is 0.5ms are shown in Figure 8 As shown in

[0155] From the above, the measuring method and the measuring device provided by the application can measure the magnetic characteristic parameters of the ferromagnetic material under single or multiple continuous pulse working conditions, the pulse excitation times, the excitation voltage, the pulse excitation amplitude and the excitation interval are adjustable, the magnetic characteristic test and evaluation of the ferromagnetic material can be carried out for different pulse working conditions, the theoretical support and the experimental basis are provided for the optimal design of the magnetic core, the actual working conditions of the pulse power equipment are more in line with, the engineering applicability of the test results is improved, and the magnetic hysteresis characteristics, the loss characteristics and the change rule of the magnetic characteristics of the material under different pulse parameters can be effectively measured, more accurate basis is provided for the selection of the magnetic core. Through the in-depth analysis of the magnetic characteristics, the application can provide guidance for the structure optimization, material selection and working parameter setting of the magnetic core of the pulse power equipment, and improve the overall performance and reliability of the equipment.

[0156] In several embodiments provided in the present application, it should be understood that the disclosed apparatus and method can be implemented in other manners. For example, the described apparatus embodiments are merely schematic. The division of the units is merely a logical function division. There can be another division manner in actual implementation. For example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed coupling or direct coupling or communication connection between the units can be indirect coupling or communication connection through some interfaces, devices or units, and can be electrical, mechanical or other forms.

[0157] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e. they can be located in one place, or distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0158] In addition, each functional unit in each embodiment of the application can be integrated into a processing unit, or each functional unit can be a separate physical unit, or two or more functional units can be integrated into a processing unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0159] If the integrated unit is implemented in the form of a software function unit and sold or used as an independent product, it can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application essentially or the part that contributes to the prior art or the whole or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the embodiments of the method of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various media that can store program codes.

[0160] The terms "first", "second", "third", "fourth" and the like in the description of the present application and the above-mentioned drawings, if any, are used to distinguish similar objects, and do not necessarily have to describe a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0161] It should also be noted that in the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0162] The above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can modify the technical solutions recorded in the foregoing embodiments, or make equivalent substitutions for part of the technical features; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for measuring the magnetic property parameters of ferromagnetic materials, characterized in that, The application is applied to a magnetic characteristic parameter measuring device of ferromagnetic material, the device comprises an excitation coil and a secondary coil which are coupled, a sample to be measured is arranged in the excitation coil and the secondary coil, the secondary coil is connected with an integrating resistor and an integrating capacitor in series, and the method comprises the following steps: In a pulse excitation environment, the excitation current of the excitation coil and the capacitor voltage of the integrating capacitor are obtained; The effective cross-sectional area, the integrating capacitor value, the integrating resistor value, the secondary winding number, the excitation winding number, the equivalent magnetic path length, the coil resistance of the excitation coil and the input instantaneous power of the sample to be measured are obtained; The magnetic induction intensity is calculated according to the effective cross-sectional area, the integrating capacitor value, the integrating resistor value, the secondary winding number and the capacitor voltage; The excitation magnetic field intensity is calculated according to the excitation current, the excitation winding number and the equivalent magnetic path length; The magnetic core loss of the sample to be measured is calculated according to the excitation current, the coil resistance and the input instantaneous power.

2. The method of claim 1, wherein, Further comprising: The magnetization time of the sample to be measured is obtained, the magnetic core loss power is obtained by dividing the magnetic core loss by the magnetization time.

3. The method of claim 1, wherein, Further comprising: The effective volume of the magnetic core of the sample to be measured is obtained, and the magnetic core loss density is obtained by dividing the magnetic core loss by the effective volume of the magnetic core.

4. The method of claim 3, wherein, Further comprising: The initial magnetization energy loss density is calculated according to the excitation magnetic field intensity and the magnetic induction intensity; The eddy current and additional loss is calculated according to the magnetic core loss density and the initial magnetization energy loss density.

5. The method of claim 1, wherein, The magnetic core loss of the sample to be measured is calculated according to the excitation current, the coil resistance and the input instantaneous power, which comprises the following steps: The excitation winding joule loss is obtained by integrating the product of the square of the excitation current and the coil resistance; The magnetic core loss of the sample to be measured is obtained by subtracting the integrating input instantaneous power from the excitation winding joule loss.

6. An electronic device, comprising: The device comprises a processor and a memory: The memory is used for storing program code and transmitting the program code to the processor; The processor is used for executing the method according to the instructions in the program code.

7. A device for measuring a magnetic property parameter of a ferromagnetic material, characterized in that Comprising: The excitation coil and the secondary coil which are coupled, a current and voltage acquisition module, and the electronic device of claim 6 are arranged; The sample to be measured is arranged in the excitation coil and the secondary coil, and the secondary coil is connected with an integrating resistor and an integrating capacitor in series; The excitation coil is connected with a pulse current generating assembly; The current and voltage acquisition module is connected with the electronic device and is used for acquiring the excitation current of the excitation coil and the capacitor voltage of the integrating capacitor.

8. The measuring device of claim 7, wherein, The pulse current generating assembly comprises a pulse power supply module; The pulse power supply module is connected with two ends of a diode and is connected with two ends of the excitation coil through the two ends of the diode; A discharge switch is arranged at the connection position of the pulse power supply module and the diode; The discharge switch is connected with a discharge control unit.

9. The measuring device of claim 8, wherein, The pulse power supply module comprises a direct-current voltage regulating power supply and a pulse capacitor; The direct-current voltage regulating power supply is connected with the pulse capacitor; The pulse capacitor is connected across the diode and across the excitation coil through the diode; The discharge switch is arranged at the connection between the pulse capacitor and the diode.

10. The measuring device of claim 9, wherein, The number of the excitation coil is one or more; the connection mode of the multiple excitation coils is parallel or grouping; The number of the pulse capacitor is one or more; the multiple pulse capacitors are connected in series or parallel; The number of the diode is one or more, and the multiple diodes are connected in parallel.

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