Magnet coil monitoring method and system

Abstract

The invention provides a magnet coil monitoring method and system, and the method comprises the steps: obtaining a first voltage signal and a first current signal of pulse discharge in each pulse discharge process of a discharge circuit of a magnet coil; performing phase alignment on the first voltage signal and the first current signal to obtain a second voltage signal and a second current signal after phase alignment; calculating the impedance of the magnet coil during each pulse discharge by using the second voltage signal and the second current signal; determining a loss factor change characteristic of the magnet coil based on the impedances during the at least two pulse discharges; the magnet coil is monitored based on the loss factor change characteristic. In a transient pulse discharge mode of a magnet coil of a nuclear fusion device, phase alignment is carried out on current and voltage, loss factor change characteristics in at least two pulse discharge processes are calculated by using the current and the voltage after phase alignment, the aging / fault development trend of the magnet coil is accurately, rapidly and visually monitored, and early warning is carried out in advance.

Description

Technical Field

[0001] The present invention relates to the field of controllable nuclear fusion technology, and particularly relates to a method and system for monitoring magnet coils. Background Art

[0002] Fusion magnet coils are characterized by large passing currents, strong electromagnetic force bearing capacity, and high surrounding magnetic field intensity. Under the action of multiple factors such as overcurrent, overheating, electromagnetic force, and material aging during use, they will gradually age and fail with the increase of service life and number of times. It is necessary to conduct on-line monitoring of fusion magnet coils, timely discover their fault data, and avoid direct insulation faults of coils and equipment damage caused by the accumulation of coil aging factors.

[0003] Due to the uniqueness of the structure and working environment of fusion magnet coils, it is impossible to monitor and compare a single branch of the coil separately, and the strong magnetic field around the coil will interfere with measuring instruments. Therefore, it is difficult to implement the method of monitoring inside and on the surface of the coil, and the results directly measured near it are severely affected by the strong magnetic field interference, and accurate monitoring results cannot be obtained.

[0004] Therefore, how to effectively and accurately monitor the magnet coil in the transient pulse discharge mode of a nuclear fusion device has become an urgent technical problem to be solved. Summary of the Invention

[0005] An embodiment of the present invention provides a method for monitoring a magnet coil, which solves the existing technical problem of how to effectively and accurately monitor the magnet coil in the transient pulse discharge mode of a nuclear fusion device.

[0006] To overcome the above technical problems, according to an embodiment of the present invention, there is provided a method for monitoring a magnet coil, including: during each pulse discharge of the discharge circuit of the magnet coil, acquiring a first voltage signal and a first current signal of the pulse discharge; aligning the phases of the first voltage signal and the first current signal to obtain a second voltage signal and a second current signal after phase alignment; calculating the impedance of the discharge circuit of the magnet coil during each pulse discharge by using the second voltage signal and the second current signal; determining the change characteristics of the loss factor of the magnet coil based on the impedance during at least two pulse discharges; and monitoring the magnet coil based on the change characteristics of the loss factor.

[0007] In one embodiment, the aligning the phases of the first voltage signal and the first current signal includes: calculating the phase difference between the first voltage signal and the first current signal; and aligning the phases of the first voltage signal and the first current signal based on the phase difference.

[0008] In one embodiment, calculating the phase difference between the first voltage signal and the first current signal includes: segmenting one of the first voltage signal and / or the first current signal by using a sampling frequency and a main pulse discharge frequency; calculating a cross-correlation sequence for each signal segment respectively; determining the peak position of each cross-correlation sequence; and performing vertex position fitting within the domain of the peak position to obtain the phase difference.

[0009] In one embodiment, performing vertex position fitting within the domain of the peak position includes: respectively performing parabolic fitting on the domain of the peak position of each signal segment, and taking the vertex of the fitted parabola as the time delay corresponding to the current signal segment; calculating the median of the time delays corresponding to all signal segments to obtain the phase difference.

[0010] In one embodiment, phase-aligning the first voltage signal and the first current signal based on the phase difference includes: performing circular shift on the first voltage signal or the first current signal according to the phase difference to phase-align the first voltage signal and the first current signal, and obtaining the phase-aligned second voltage signal and second current signal; and performing interpolation filling on the boundary of the second voltage signal or the second current signal.

[0011] In one embodiment, before determining the change characteristic of the loss factor of the magnet coil based on the impedance during at least two pulse discharges, it includes: performing moving average filtering on the impedance.

[0012] In one embodiment, monitoring the magnet coil based on the change characteristic of the loss factor includes: calculating the change rate of the loss factor between different pulse discharges; and outputting an alarm signal when the change rate of the loss factor is greater than a preset change rate.

[0013] In one embodiment, calculating the change rate of the loss factor between different pulse discharge processes includes: obtaining the loss factors during the previous N pulse discharge processes as standard loss factors, where N is an integer greater than or equal to 1; respectively calculating the difference between the loss factor during each pulse discharge process and the standard loss factor; and calculating the ratio of the difference to the standard value as the change rate of the loss factor.

[0014] According to a second aspect, an embodiment of the present application provides a magnet coil monitoring system, including: a voltage acquisition module for acquiring a first voltage signal during the process of pulse discharge of the discharge circuit of the magnet coil; a current acquisition module for acquiring a first current signal during the process of pulse discharge of the discharge circuit of the magnet coil; and a data processing module for receiving the first voltage signal and the first current signal and executing the magnet coil monitoring method according to any one of the first aspects above.

[0015] In one embodiment, the voltage acquisition module includes: a voltage divider circuit and a first isolation differential amplifier connected to the output section of the voltage divider circuit, where the first isolation differential amplifier is configured to suppress common-mode interference for the first voltage signal; the current acquisition module includes a shunt resistor and a second isolation differential amplifier connected to the output terminal of the shunt resistor, where the isolation differential amplifier is configured to suppress common-mode interference for the first current signal; the data processing module includes a data collector, which is configured to convert the first current signal and the first voltage signal into corresponding digital signals.

[0016] The technical solution provided by the embodiments of the present invention may include the following beneficial effects:

[0017] In this application, during each process of the pulsed power supply discharging pulses to the magnet coil, the first voltage signal and the first current signal of the pulsed discharge are acquired; since there is a phase difference between the current and voltage in the magnet coil circuit during the transient pulsed discharge, the first voltage signal and the first current signal are phase-aligned to obtain the second voltage signal and the second current signal after phase alignment; the impedance of the magnet coil during each pulsed discharge is calculated using the second voltage signal and the second current signal after phase alignment; the variation characteristics of the loss factor of the magnet coil are determined based on the impedance during at least two pulsed discharges; the magnet coil is monitored based on the variation characteristics of the loss factor. It is possible to accurately, quickly, and intuitively monitor the aging / fault development trend in the discharge loop of the magnet coil in the transient pulsed discharge mode of the magnet coil in the nuclear fusion device, and give an early warning before a major fault occurs.

[0018] Further, calculate the difference between the loss factor in the current pulse discharge process and the loss factors in the previous N pulse discharge processes. Using the same measurement parameters, compare the loss factor curve tanδ obtained from the subsequent pulse discharge processes with it to obtain the loss factor change rate curve. The loss factor change rate is the relative change degree (i.e., the percentage of the difference between the current loss factor and the standard loss factor to the standard loss factor), which can associate the absolute difference with the original standard value and magnify the tiny changes. And it has nothing to do with the magnitude of the original value of the loss factor. Whether the loss factor itself is large or small, the loss factor change rate can fairly measure the severity of its change. In the initial stage of equipment aging or failure, the change of the loss factor is often small and not easily detectable directly. However, the loss factor change rate can highlight this tiny relative change and can detect abnormal trends in advance. Utilizing the sensitivity of the change rate to early tiny changes to avoid being ignored due to a small absolute difference, thus enabling early warning and preventing the expansion of faults.

[0019] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings herein are incorporated into the specification and form a part of the specification, showing embodiments consistent with the present invention and, together with the specification, are used to explain the principles of the present invention.

[0021] Figure 1 is a schematic flow chart of a magnet coil monitoring method shown according to an exemplary embodiment;

[0022] Figure 2 is a schematic diagram of the monitoring effects of two magnet coil monitoring methods in the present application shown according to an exemplary embodiment;

[0023] Figure 3 is a schematic diagram of a magnet coil monitoring system shown according to an exemplary embodiment;

[0024] Figure 4 is a schematic diagram of a magnet coil monitoring device shown according to an exemplary embodiment;

[0025] Figure 5 is a schematic diagram of the data processing module of the magnet coil monitoring system shown according to an exemplary embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] Among them, the accompanying drawings are only for illustrative purposes, showing only schematic diagrams rather than physical diagrams, and should not be construed as a limitation to this patent; in order to better illustrate the embodiments of the present invention, some components in the accompanying drawings may be omitted, enlarged or reduced, which do not represent the dimensions of the actual products; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the accompanying drawings may be omitted.

[0027] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components; in the description of the present invention, it should be understood that if terms such as "upper", "lower", "left", "right", "inner", "outer", etc. are used to indicate the orientation or positional relationship, it is based on the orientation or positional relationship shown in the accompanying drawings. This is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the accompanying drawings are only for illustrative purposes and should not be construed as a limitation to this patent. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0028] In the description of the present invention, unless otherwise clearly specified and defined, if terms such as "connection" are used to indicate the connection relationship between components, this term should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] In some related technologies, there are methods for monitoring the state of inductors. For example, in the field of power grid technology, there are some methods for monitoring air-core inductors, such as temperature field monitoring, equivalent inductance monitoring, equivalent impedance monitoring, distributed magnetic field monitoring, time-domain current monitoring, and current harmonic monitoring. However, when the applicant uses the inductor state monitoring method to detect the magnet coils in a nuclear fusion device, it is difficult to perform accurate monitoring. Through the applicant's research, it is found that the methods for monitoring air-core inductors in the field of power grid technology often monitor the state of air-core inductors based on steady-state data. However, the pulsed discharge process of the magnet coils in a nuclear fusion device is a transient pulse type, and the current reaches its peak value in a very short time and then rapidly decays. The electrical parameters change rapidly and significantly. Moreover, during the transient pulse discharge process, due to the essential differences in frequency characteristics, load types, signal forms, and energy conversion between the air-core inductors in a steady-state power grid, the existing steady-state monitoring methods cannot accurately capture the fault parameters in the magnet coils. Taking the equivalent impedance monitoring method as an example, for the accurate monitoring of air-core inductors in the field of power grid technology, it is difficult to achieve the accurate monitoring of magnet coils because in the power grid, its frequency is a fixed frequency, and the inductor is often a linear inductor. Therefore, its impedance is fixed, or it can be accurately calculated through current and voltage. Therefore, when the monitoring parameters are all in a steady state, accurate monitoring can be performed. However, the inductance of the magnet coil is strongly non-linear, and its frequency is a transient frequency, and the reactance is a dynamic reactance. Therefore, it is difficult to perform accurate monitoring through the steady-state monitoring methods in the field of power grid technology.

[0030] In addition, when directly monitoring and comparing the discharge circuit impedance and inductance of the magnet coil, due to the influence of factors such as instrument error and electromagnetic interference, the slight changes that occur can only collect fault data when there are drastic changes such as direct failure of the magnet coil, and cannot give an early warning before an accident occurs in the coil. Therefore, it is difficult to use the steady-state monitoring methods in the field of power grid technology to perform accurate monitoring in the magnet coil monitoring of a nuclear fusion device.

[0031] Based on this, the present application provides a method for monitoring magnet coils, which is applicable to the online monitoring of magnet coils in a nuclear fusion device under a transient pulse discharge mode, as Figure 1 shown. The method for monitoring magnet coils includes the following steps:

[0032] S101. During each pulse discharge of the discharge circuit of the magnet coil, obtain the first voltage signal and the first current signal of the pulse discharge. In a nuclear fusion device, an energy storage device is often used to perform pulse discharge on the magnet coil. For example, a capacitor module is used to perform transient pulse discharge on the magnet coil. The magnet coil operates in a pulse discharge mode. Before the pulse discharge, the coil can use an external power supply to charge the energy storage device. After the charging is completed, according to the discharge control instruction, the main circuit power switch is closed for a certain time length, and the energy storage device discharges the magnet coil; the instantaneous value of the discharge voltage of the energy storage device and the instantaneous value of the current on the magnet coil during the pulse discharge process are obtained through a voltage and current measurement system as the first voltage signal and the first current signal respectively. In this embodiment, the first current signal and the first voltage signal collected are time-domain data during the pulse discharge process, and the first current signal and the first voltage signal have transient and aperiodic characteristics. Due to the existence of this characteristic in the first current signal and the first voltage signal during the pulse discharge process, there is a phase difference between the first current signal and the first voltage signal, and this phase difference is not fixed but dynamically changes in the discharge device. Therefore, directly using the current data and voltage data to monitor the magnet coil results in a large monitoring error. Based on this, step S102 is executed.

[0033] S102. Align the phases of the first voltage signal and the first current signal to obtain the second voltage signal and the second current signal after phase alignment. Since there is a phase difference between the first current signal and the first voltage signal, when using the first current signal and the first voltage signal to monitor the magnet coil, it is necessary to first align the phases of the first voltage signal and the first current signal. In this embodiment, the phase alignment method can be through phase compensation. Exemplarily, perform a short-time Fourier transform on the collected signal, extract the phase differences of each frequency component, and compensate the phase differences through an all-pass filter. It can also be compensated online adaptively through the least mean square error algorithm. It is also possible to perform frequency-domain analysis on the time-domain data of the first current signal and the first voltage signal, calculate the phase difference, and then shift according to the phase difference to align the phases of the first voltage signal and the first current signal, obtaining the second voltage signal and the second current signal after phase alignment.

[0034] S103. Calculate the impedance of the magnet coil during each pulse discharge using the second voltage signal and the second current signal. In this embodiment, according to the impedance Z = Uc / Ic, the total line impedance is obtained, where Uc is the second voltage signal after phase alignment, Ic is the second current signal after phase alignment, and Z is the total impedance in the magnet coil discharge circuit. Among them, the total impedance Z = R + jX, R is the equivalent resistance of the discharge circuit, that is, the real part of the impedance. The equivalent resistance R includes the internal resistance of the capacitor module, the line resistance, and the magnet coil resistance. This value can be obtained through single-cell testing before the assembly of the magnet coil discharge circuit. X is the reactance component of the impedance, that is, the imaginary part of the impedance.

[0035] S104. Determine the change characteristics of the loss factor of the magnet coil based on the impedance during at least two pulse discharges. In this embodiment, the change characteristics of the loss factor can be the difference in the loss factor during different pulse discharge processes, or the change rate of the loss factor during different pulse discharge processes.

[0036] S105. Monitor the magnet coil based on the change characteristics of the loss factor.

[0037] Define the ratio of the real part and the imaginary part of the impedance as the loss factor, tanδ = R / X. Among them, R is the real part of the impedance, that is, the equivalent resistance of the discharge circuit, and X is the reactance component of the impedance, that is, the imaginary part of the impedance. Among them, the reactance component of the impedance is composed of the capacitive reactance of the bus capacitor and the inductive reactance of the magnet coil, and can be obtained according to the following formula:

[0038]

[0039] After obtaining the real part and the imaginary part of the impedance respectively, the loss factor during the current pulse discharge process is obtained through the ratio of the real part and the imaginary part. When the magnet discharge circuit gradually ages with the service life and number of times, and faults such as a decrease in the capacitance value of the capacitor or an increase in the circuit resistance and a decrease in the inductance caused by a magnet coil failure occur, the loss factor will change. Therefore, the magnet coil is monitored in real time through the change characteristics of the loss factor monitored at least twice.

[0040] In this application, during each pulse discharge of the magnet coil by the pulse power supply, a first voltage signal and a first current signal of the pulse discharge are acquired; due to the phase difference between the current and voltage in the magnet coil circuit of the transient pulse discharge, the first voltage signal and the first current signal are phase-aligned to obtain a second voltage signal and a second current signal after phase alignment; the impedance of the magnet coil during each pulse discharge is calculated using the second voltage signal and the second current signal after phase alignment; the change characteristics of the loss factor of the magnet coil are determined based on the impedance during at least two pulse discharges; and the magnet coil is monitored based on the change characteristics of the loss factor. It is possible to accurately, quickly, and intuitively monitor the aging / fault development trend in the discharge circuit of the magnet coil in the transient pulse discharge mode of the magnet coil of the nuclear fusion device, and give an early warning before a major fault occurs.

[0041] When the magnet discharge circuit gradually ages over the years and number of uses, and faults such as a decrease in the capacitance value of the capacitor or an increase in the circuit resistance and a decrease in the inductance caused by a magnet coil fault occur, the loss factor will change. However, since the magnet coil discharge is a transient pulse discharge, the absolute value of the change in the loss factor monitored each time may be small. When a large change in the absolute value of the loss factor is detected, the circuit of the magnet coil has often suffered a device damage fault. Therefore, it may be difficult to give a more accurate early warning before a major fault occurs by directly monitoring the difference in the loss factor during different pulse discharges. Therefore, in order to improve the accuracy and foresight of the monitoring, in this embodiment, the difference in the loss factor between different pulse discharge processes is acquired; the change rate of the loss factor is calculated based on the difference; and when the change rate is greater than a preset change rate, an alarm signal is output.

[0042] In this embodiment, when calculating the loss difference, the difference between the loss factor in the current pulse discharge process and the loss factors in the previous N pulse discharge processes can be calculated, where N is greater than or equal to 1. Exemplarily, the loss factor curve obtained from the initial discharge test of the magnet coil circuit can be used as the standard value Tanδ. For example, the loss factor obtained from the first pulse discharge process can be used as the standard value Tanδ. Of course, the loss factors of the first 5 or first 10 pulse discharges can also be used as the standard value Tanδ. Using the same measurement parameters, the loss factor curve tanδ obtained from the subsequent pulse discharge processes is compared with it, and the change rate Δtanδ of each measurement value is monitored, Δtanδ = (Tanδ - tanδ) / Tanδ * 100%, to obtain the loss factor change rate curve.

[0043] The loss factor change rate is the relative degree of change (that is, the difference between the current loss factor and the standard loss factor and the percentage of the standard loss factor), which can associate the absolute difference with the original standard value and amplify small changes. And it has nothing to do with the original value of the loss factor. Regardless of whether the loss factor itself is large or small, the rate of change can fairly measure the severity of its change. In the early stages of equipment aging or failure, the change in loss factor is often small and not easy to detect directly. However, the loss factor change rate can highlight this small relative change and detect abnormal trends in advance. For example, when the maximum value of the loss factor change rate is 5%, an early warning signal can be output. In this embodiment, the sensitivity of the change rate to early small changes is used to avoid being ignored due to small absolute differences, thereby achieving early warning and preventing the expansion of faults. For details, please refer to Figure 2 The schematic diagram of the test results using the loss factor change rate and loss factor difference is shown. Among them, tanδ1 is the first loss factor, tanδ2 is the second loss factor, Δtanδ1 is the change rate between the first loss factor and the standard loss factor Tanδ, and Δtanδ2 is the change rate between the second loss factor and the standard loss factor Tanδ. It can be seen that as time A to H, the loss factor change rate can amplify the slight change in the loss factor and detect abnormal trends in advance.

[0044] In another embodiment, when calculating the change rate of the loss factor, the change rate of the loss factor may be calculated based on the difference between the current loss factor and the loss factors of the previous N times.

[0045] In one embodiment, the phase-aligning the first voltage signal and the first current signal comprises:

[0046] Calculate the phase difference between the first voltage signal and the first current signal. In the present embodiment, since the circuit of the magnetic coil is in the form of transient pulse discharge during the pulse discharge process, its discharge waveform is a non-sinusoidal discharge, and the frequency variation range changes from DC to high frequency instantly, and factors such as the nonlinear characteristics of the inductance and capacitance present in the circuit cause the phase difference between the first current signal and the first voltage signal to be not fixed, but dynamically changes as the discharge proceeds. Therefore, in the present embodiment, when calculating the phase difference, the collected first voltage signal and / or first current signal can be segmented, and the voltage and current signals after segmentation can be cross-correlated, and parabola fitting can be performed to calculate the phase difference between the first voltage signal and the first current signal. Exemplarily, the first voltage signal can be segmented, and the first current signal can also be segmented. In the present embodiment, the segmentation of the first current signal can be used as an example for illustration:

[0047] The first current signal is segmented using the sampling frequency and the pulse discharge main frequency. The length of each segment is dynamically set according to the pulse discharge main frequency:

[0048] L segment = max(round(f main / F s ), t)

[0049] Fs is the data sampling rate, fmain is the main frequency of the transient pulse; t is the minimum length set according to the size of the test data.

[0050] Calculate the cross-correlation sequence with the first voltage signal for each segment of the current signal respectively. Among them, the following formula can be used for calculation:

[0051] Calculate the cross-correlation sequence for each segment of the signal:

[0052]

[0053] Among them, V[n] is the value of the voltage signal at the nth sampling point. (I[n + k] is the value of the first current signal at the (n + k)th sampling point, and k is the time offset of the first current signal relative to the first voltage signal. L is the length of each segment of the signal.

[0054] By measuring the similarity between the first voltage signal and the first current signal at different time offsets k. By traversing all possible time offsets k, calculate the sum of the products of the first voltage signal and the first current signal at the corresponding positions. When the time offset k makes the waveforms of the first voltage signal and the first current signal match best, the peak position of each cross-correlation sequence can be determined, that is, when R V,I [k] obtains the peak value, so as to locate the time delay relationship between the first voltage signal and the first current signal.

[0055] The peak position of the cross-correlation calculation May be limited by the sampling interval, and the accuracy only reaches the sampling period level. Therefore, for the accuracy of the phase difference calculation, in this embodiment, vertex position fitting is performed within the domain of definition of the peak position to obtain the phase difference. Specifically, the cross-correlation peak position can be determined, and then within the vicinity of the peak position, that is, within the domain of definition of the peak position, quadratic fitting is performed to obtain the accurate peak position. Exemplarily, a parabola fitting method can be used to obtain the vertex within the domain of definition of the peak value as the true peak position.

[0056] Specifically, the parabola formula: R(k) = ak^2 + bk + c can be used to fit the data near the peak value. According to the parabola vertex formula: k opt = -b / 2a, calculate the optimal time delay. To solve the time delay with sub-sampling accuracy and improve the fineness of the time delay calculation.

[0057] After obtaining the time delays with sub-sampling accuracy for each segment of the signal respectively, the median of all segment time delays can be used as the phase difference.

[0058] After obtaining the phase difference, align the phase of the first voltage signal and the first current signal based on the phase difference. In this embodiment, cyclically shift the first current signal according to the phase difference to align the phase of the first current signal and the first voltage signal. Among them, the following formula can be used for cyclic shift alignment:

[0059] I corrected [n]=I[n + Δφ]

[0060] I[n] is the value of the first current signal at the nth sampling point; Δφ is the phase difference; I corrected[n] is the value of the corrected second current signal at the nth sampling point. Interpolate and fill the boundary of the shifted second current signal. Cyclically shift the first current signal according to the phase difference Δφ to align the first voltage signal and the first current signal in time (phase synchronization). The boundary is filled by linear interpolation to avoid signal truncation or discontinuity caused by the shift and ensure the integrity and physical meaning of the corrected signal.

[0061] After obtaining the second current signal and the second voltage signal after phase correction, calculate the total line impedance using the second current signal and the second voltage signal. Since the collected data may contain interference noise from instruments or the environment, to avoid drastic fluctuations when calculating the loss factor, the following formula is used for moving average filtering of the impedance value:

[0062]

[0063] Among them, Z smooth[n] is the impedance value after moving average filtering at the nth data point. W is the width of the moving window, which determines the number of points participating in the average. Z[n + k] is the impedance value at the position offset by k centered on n in the original impedance data.

[0064] The embodiment of the present application also provides a magnet coil monitoring system, as Figure 3 shown, including:

[0065] A voltage acquisition module 100, a current acquisition module 200, and a data processing module 300. Among them, the voltage acquisition module 100 is used to acquire the first voltage signal during the pulse discharge of the discharge circuit of the magnet coil, and the current acquisition module 200 is used to acquire the first current signal during the pulse discharge of the discharge circuit of the magnet coil; the data processing module is used to receive the first voltage signal and the first current signal and execute the magnet coil monitoring method described in the above embodiment.

[0066] Specifically, the voltage acquisition module 100 includes: a voltage divider circuit and a first isolation differential amplifier connected to the output section of the voltage divider circuit. The first isolation differential amplifier is used to suppress common-mode interference of the first voltage signal; the current acquisition module 200 includes a shunt resistor and a second isolation differential amplifier connected to the output end of the shunt resistor. The isolation differential amplifier is used to suppress common-mode interference of the first current signal; the data processing module includes a data collector, which is used to convert the first current signal and the first voltage signal into corresponding digital signals.

[0067] In this embodiment, the voltage divider circuit collects the instantaneous value of the output voltage in the discharge circuit through resistor voltage division, and its output end is connected to the first isolation differential amplifier; the output end of the first isolation differential amplifier is connected to the data collector; after suppressing common-mode interference of the first voltage signal through differential amplification, it outputs according to the required ratio. The first isolation differential amplifier can adopt an opto-isolation amplifier. Its bandwidth is DC~1MHz, which can meet the requirements of transient pulse data acquisition.

[0068] The shunt resistor collects the instantaneous value of the output current in the discharge circuit, and its output end is connected to the second isolation differential amplifier. The output end of the second isolation differential amplifier is connected to the data collector; after suppressing common-mode interference of the first current signal through differential amplification, it outputs according to the required ratio. The second isolation differential amplifier can adopt an opto-isolation amplifier. Its bandwidth is DC~1MHz, which can meet the requirements of transient pulse data acquisition.

[0069] The first isolation differential amplifier and the second isolation differential amplifier use a metal shell with good grounding to cope with the complex electromagnetic environment on site.

[0070] Through differential measurement and opto-isolation technology and optimizing the position of the measurement sensor, the interference of strong magnetic fields on the measurement results is avoided, ensuring the accuracy of the monitoring data and the safety of the backend equipment; at the same time, the change range of the circuit electrical parameters is amplified, and abnormalities can be detected in time when there are small changes in the electrical parameters of the magnet coil, improving the sensitivity of the monitoring.

[0071] Data collector: Receives the first voltage signal and the first current signal collected by the voltage acquisition module 100 and the current acquisition module 200, converts the analog quantity into a digital quantity, and outputs it to the data processing module. The sampling rate of the data collector is above 10MHz, and it can capture the rapid current and voltage change values during the transient pulse discharge process. The data collector is installed in a shielded room with good grounding.

[0072] This embodiment provides a magnet coil monitoring device, as Figure 4 shown, including:

[0073] The first acquisition module 401 is configured to acquire a first voltage signal and a first current signal of the pulsed discharge during each pulsed discharge of the discharge circuit of the magnet coil.

[0074] The phase alignment module 402 is configured to perform phase alignment on the first voltage signal and the first current signal to obtain a second voltage signal and a second current signal after phase alignment.

[0075] The impedance calculation module 403 is configured to calculate the impedance of the magnet coil during each pulsed discharge by using the second voltage signal and the second current signal.

[0076] The loss factor calculation module 404 is configured to determine the change characteristic of the loss factor of the magnet coil based on the impedances during at least two pulsed discharges.

[0077] The monitoring module 405 is configured to monitor the magnet coil based on the change characteristic of the loss factor.

[0078] It should be noted here that the examples and application scenarios implemented by the above modules and the corresponding steps are the same, but are not limited to the content disclosed in the above embodiments.

[0079] It should be noted that the above modules can be implemented by software or hardware as part of the device. Among them, the hardware environment includes a network environment.

[0080] The embodiment of the present invention further provides a data processing module. The data processing module can adopt a computer device, including a processor, a communication interface, a memory, and a communication bus. Among them, the processor, the communication interface, and the memory complete communication with each other through the communication bus. The memory is used to store a computer program. The processor is configured to execute the method in the embodiment of any one of the above by running the computer program stored on the memory.

[0081] Figure 5 is a structural block diagram of an optional computer device according to an embodiment of the present application. As Figure 5 shown, it includes a processor 10, a communication interface 20, a memory 30, and a communication bus 40. Among them, the processor 10, the communication interface 20, and the memory 30 complete communication with each other through the communication bus 40. Among them,

[0082] The memory 30 is used to store a computer program.

[0083] When the processor 10 is configured to execute the computer program stored on the memory 30, it implements the method of any of the above embodiments.

[0084] Optionally, in this embodiment, the aforementioned communication bus may be a PCI (Peripheral Component Interconnect) bus, an EISA (Extended Industry Standard Architecture) bus, or the like. The communication bus can be divided into an address bus, a data bus, a control bus, etc. For the sake of convenience of representation, Figure 5 it is only represented by a thick line in the figure, but it does not mean that there is only one bus or one type of bus.

[0085] The communication interface is used for communication between the aforementioned computer device and other devices.

[0086] The memory may include RAM and may also include non-volatile memory, for example, at least one disk memory. Optionally, the memory may also be at least one storage device located far from the aforementioned processor.

[0087] The aforementioned processor may be a general-purpose processor, which may include but is not limited to: a CPU (Central Processing Unit), an NP (Network Processor), etc.; it may also be a DSP (Digital Signal Processing), an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0088] Optionally, the specific examples in this embodiment may refer to the examples described in the above embodiments, and will not be elaborated here.

[0089] Those of ordinary skill in the art can understand that Figure 5 the structure shown is only schematic. The device for implementing the method of any one of the above embodiments may be a terminal device, and the terminal device may be a smart phone (such as an Android phone, an IOS phone, etc.), a tablet computer, a palm computer, and a mobile Internet device (MID), a PAD, and other terminal devices. Figure 5 It does not limit the structure of the above electronic device. For example, the terminal device may also include more or fewer components (such as a network interface, a display device, etc.) than those shown Figure 5 in the figure, or have a structure different from that shown Figure 5The different configurations shown.

[0090] Those of ordinary skill in the art can understand that all or part of the steps in the various methods of the above embodiments can be completed by instructing the relevant hardware of the terminal device through a program, and the program can be stored in a computer-readable storage medium, and the storage medium can include: a flash drive, a ROM, a RAM, a magnetic disk, or an optical disc, etc.

[0091] As an exemplary embodiment, the present application also provides a computer-readable storage medium, in which a computer program is stored, and the computer program is set to execute the method steps of any one of the present embodiments when running.

[0092] Optionally, in the present embodiment, the above storage medium can be used to execute the program code of the method steps of the embodiments of the present application.

[0093] Optionally, in the present embodiment, the above storage medium can be located on at least one of the multiple network devices in the network shown in the above embodiments.

[0094] Optionally, in the present embodiment, the storage medium is set to store for executing the method in the above embodiments.

[0095] Optionally, the specific examples in the present embodiment can refer to the examples described in the above embodiments, and details are not described herein again.

[0096] Optionally, in the present embodiment, the above storage medium can include but is not limited to: various media such as a USB flash drive, a ROM, a RAM, a mobile hard disk, a magnetic disk, or an optical disc that can store program code.

[0097] The serial numbers of the embodiments of the present application above are only for description and do not represent the superiority or inferiority of the embodiments.

[0098] If the integrated unit in the above embodiments is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in the above computer-readable storage medium. Based on such an understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in the storage medium and includes several instructions for causing one or more computer devices (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method in the above embodiments.

[0099] In several embodiments provided by this application, it should be understood that the disclosed client can be implemented in other ways. Among them, the device embodiments described above are only illustrative. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling, direct coupling, or communication connection to each other can be through some interfaces. The indirect coupling or communication connection of units or modules can be in an electrical or other form.

[0100] The units described as separate components may or may not be physically separated. The components displayed as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution provided in this embodiment.

[0101] In addition, in each embodiment of this application, the functional units can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above integrated units can be implemented in the form of hardware or in the form of software functional units.

[0102] In the above embodiments of this application, the descriptions of each embodiment have their own emphases. For the parts not detailed in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0103] The above is only the preferred embodiment of this application. It should be noted that for those of ordinary skill in the art, without departing from the principle of this application, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of this application.

Claims

1. A method for monitoring a magnet coil, characterized in that, Including: During each pulse discharge of the discharge circuit of the magnet coil, acquiring a first voltage signal and a first current signal of the pulse discharge; Aligning the phases of the first voltage signal and the first current signal to obtain a second voltage signal and a second current signal after phase alignment; Calculating the impedance of the discharge circuit of the magnet coil during each pulse discharge by using the second voltage signal and the second current signal; Determining the change characteristic of the loss factor of the magnet coil based on the impedances during at least two pulse discharges; Monitoring the magnet coil based on the change characteristic of the loss factor.

2. The magnet coil monitoring method according to claim 1, wherein The aligning the phases of the first voltage signal and the first current signal to obtain a second voltage signal and a second current signal after phase alignment includes: Calculating the phase difference between the first voltage signal and the first current signal; Aligning the phases of the first voltage signal and the first current signal based on the phase difference.

3. The magnet coil monitoring method according to claim 2, wherein, The calculating the phase difference between the first voltage signal and the first current signal includes: Segmenting the first voltage signal and / or the first current signal by using the sampling frequency and the main frequency of the pulse discharge; Calculating the cross-correlation sequence for each signal segment respectively; Determining the peak position of each cross-correlation sequence; Performing vertex position fitting within the domain of the peak position to obtain the phase difference.

4. The magnet coil monitoring method according to claim 3, characterized in that The performing vertex position fitting within the domain of the peak position includes: Respectively performing parabolic fitting on the domain of the peak position of each signal segment, and taking the vertex of the fitted parabola as the time delay corresponding to the current signal segment; Calculating the median of the time delays corresponding to all signal segments to obtain the phase difference.

5. The magnet coil monitoring method according to claim 2, wherein The aligning the phases of the first voltage signal and the first current signal based on the phase difference includes: Performing circular shift on the first voltage signal or the first current signal according to the phase difference to align the first voltage signal and the first current signal, and obtaining the second voltage signal and the second current signal after phase alignment; Performing interpolation filling on the boundary of the second voltage signal or the second current signal.

6. The magnet coil monitoring method according to claim 1, wherein, Before determining the change characteristic of the loss factor of the magnet coil based on the impedances during at least two pulse discharges includes: Performing moving average filtering on the impedance.

7. The magnet coil monitoring method according to claim 1, characterized in that, The monitoring the magnet coil based on the change characteristic of the loss factor includes: Calculating the change rate of the loss factor between different pulse discharges; When the change rate of the loss factor is greater than a preset change rate, outputting an alarm signal.

8. The magnet coil monitoring method according to claim 7, characterized in that, The calculating the change rate of the loss factor between different pulse discharge processes includes: Acquiring the loss factors during the first N pulse discharge processes as the standard loss factors, where N is an integer greater than or equal to 1; Respectively calculating the difference between the loss factor during each pulse discharge process and the standard loss factor; Calculating the ratio of the difference to the standard value as the change rate of the loss factor.

9. A magnet coil monitoring system, characterized in that, Including: A voltage acquisition module, configured to acquire a first voltage signal during the process of pulse discharge of the discharge circuit of the magnet coil; A current acquisition module, configured to acquire a first current signal during the process of pulse discharge of the discharge circuit of the magnet coil; and a data processing module, configured to receive the first voltage signal and the first current signal, and execute the magnet coil monitoring method according to any one of claims 1-8.

10. The magnet coil monitoring system according to claim 9, wherein, The voltage acquisition module includes: a voltage divider circuit and a first isolation differential amplifier connected to the output section of the voltage divider circuit, and the first isolation differential amplifier is configured to suppress common-mode interference of the first voltage signal; The current acquisition module includes a shunt resistor and a second isolation differential amplifier connected to the output end of the shunt resistor, and the isolation differential amplifier is configured to suppress common-mode interference of the first current signal; The data processing module includes a data collector, configured to convert the first current signal and the first voltage signal into corresponding digital signals.

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