A remote configuration and dispatch method for electronic test instruments

Abstract

The application provides a remote configuration and scheduling method of an electronic test instrument, and relates to the field of remote calibration, which comprises the following steps: obtaining a compensation excitation amplitude, an excitation starting phase, a zero residual voltage and a magnetic core working point offset, and determining a current equivalent magnetization depth of the magnetic core; according to the current equivalent magnetization depth of the magnetic core and the excitation starting phase, performing correlation analysis on the coupling response of the zero residual voltage and the magnetic core working point offset, identifying a saturation drift excitation opportunity; determining a critical combination of the excitation starting phase and the compensation excitation amplitude for triggering the saturation drift under different magnetization depths, and generating a compensation injection judgment reference; when the current excitation starting phase and the compensation excitation amplitude combination break through the critical combination, adjusting the compensation excitation amplitude and the excitation starting phase to a safe interval; performing compensation injection and collecting observation according to the adjusted compensation excitation parameters, and outputting a calibration completion mark. The application can improve the stability of remote zero point calibration and reduce the risk of bottom noise lifting.

Description

Technical Field

[0001] This invention relates to the field of remote calibration, and more particularly to a method for remote configuration and scheduling of electronic testing instruments. Background Technology

[0002] In the field of remote configuration and scheduling of electronic test instruments, the accuracy of zero-point calibration is the fundamental guarantee of the reliability of results in high-sensitivity measurement scenarios such as small current and weak signals. The remote calibration process usually clears the residual magnetism of the magnetic core by sending a compensation excitation signal, so that the sensor operating point returns to the ideal origin, thereby controlling the residual voltage of the zero-point output within an acceptable low-noise range.

[0003] Current solutions generally rely on increasing the amplitude of the compensation excitation to achieve residual magnetism removal, assuming that as long as the amplitude is large enough, the operating point of the magnetic core can be fully pulled back, and the residual magnetism will be completely canceled. This approach treats the magnetic core as a near-memoryless linear device, assuming that the amplitude and the removal effect are monotonically positively correlated.

[0004] However, the inherent hysteresis characteristics of ferromagnetic materials determine that the core's response to excitation is essentially nonlinear and path-dependent. When the core has undergone deep magnetization during previous operation and retains a specific orientation of magnetic domain alignment, excessively strong reverse compensation excitation not only fails to bring the operating point back to the ideal origin accurately, but may also push it beyond the expected return region into the saturation branch of the hysteresis loop, forming a secondary bias in the new direction. This causes the zero-point residual voltage to rise instead of fall, increasing the noise floor of subsequent measurements and resulting in a directional deviation between the compensation action and the calibration target. Further analysis of this deviation reveals that what truly determines the landing point of the compensated operating point is not the single parameter of excitation amplitude, but the coupling relationship between the excitation initial phase and the current equivalent magnetization depth of the core. The equivalent magnetization depth is an internal state quantity gradually superimposed by the core in each magnetization cycle, which can be understood as a path memory on the hysteresis loop that has not yet been released. This state quantity cannot be directly read from the excitation parameters themselves, nor can it be obtained by reverse calculation from a single zero-point output reading; rather, it is implicit in the core's past operating history.

[0005] However, under remote calibration conditions, the scheduling terminal cannot directly observe this internal state of the magnetic core. Existing scheduling logic makes decisions based solely on two macroscopic quantities: the excitation amplitude and the zero-point output reading. It lacks both the means to perceive and the basis for judging the coupling effect between the excitation start phase and the equivalent magnetization memory. This means that when a specific start phase happens to form an unfavorable combination with the current magnetization memory state, the scheduling logic cannot identify the resulting saturation drift risk, and the compensation command may instead push the operating point into the deteriorated section of the hysteresis loop. Therefore, accurately identifying the saturation drift risk induced by the coupling between the excitation start phase and the equivalent magnetization memory within the remote calibration framework, where the historical magnetization state of the magnetic core cannot be directly observed, and avoiding the compensation action from negatively increasing the noise floor of small current measurements, becomes a key issue in achieving stable zero-point calibration of electronic test instruments. Summary of the Invention

[0006] This invention provides a method for remote configuration and scheduling of electronic testing instruments, mainly including: Obtain the compensation excitation amplitude, excitation start phase, zero-point residual voltage and core operating point offset, and determine the current equivalent magnetization depth of the core; Based on the current equivalent magnetization depth of the magnetic core and the excitation start phase, a correlation analysis is performed on the coupling response between the zero-point residual voltage and the magnetic core operating point offset to identify the saturation drift excitation timing induced by the coupling between the excitation start phase and the current equivalent magnetization depth of the magnetic core. Based on the saturation drift excitation timing, the critical combination of the excitation start phase and the compensation excitation amplitude that trigger saturation drift at different magnetization depths is determined, and a compensation injection judgment criterion is generated. Based on the compensation injection judgment criteria, the combination of the current excitation start phase and the compensation excitation amplitude is compared. When the critical combination is exceeded, the compensation excitation amplitude and the excitation start phase are adjusted to a safe range to obtain the adjusted compensation excitation parameters. Compensation injection is performed according to the adjusted compensation excitation parameters. The zero-point residual voltage and noise floor level after compensation are collected. A calibration completion mark is output when the zero-point residual voltage returns to the preset threshold and the noise floor level is lower than the measurement tolerance value.

[0007] The technical solutions provided by the embodiments of the present invention may include the following beneficial effects: This invention discloses a remote configuration and scheduling method for electronic test instruments. Addressing the problem of relying solely on the compensation excitation amplitude while neglecting the core hysteresis path memory during remote zero-point calibration, this invention proposes a closed-loop scheduling scheme based on the coupling relationship between the excitation start phase, the compensation excitation amplitude, and the current equivalent magnetization depth of the core. The invention determines the current equivalent magnetization depth of the core through low-disturbance detection excitation and performs correlation analysis on the coupling response between the zero-point residual voltage and the core operating point offset to identify the saturation drift excitation timing induced by both phase and magnetization depth. Furthermore, it constructs a compensation injection judgment benchmark based on different magnetization depth levels and selects the safe interval with the smallest deviation to perform compensation injection when the current compensation excitation parameters exceed the critical combination. This reduces the risk of the compensation excitation pushing the core operating point into the saturation branch of the hysteresis loop, improves the stability of remote zero-point calibration, reduces noise floor increase, and provides a clear iterative backoff and termination mechanism for the calibration process in abnormal scenarios. Attached Figure Description

[0008] Figure 1 This is a flowchart of a remote configuration and scheduling method for electronic testing instruments according to the present invention.

[0009] Figure 2 This is a flowchart illustrating the determination of the current equivalent magnetization depth of a magnetic core and the identification of the saturation drift excitation timing according to the present invention.

[0010] Figure 3 This is a flowchart illustrating the process of generating a compensation injection determination benchmark, selecting a safe range, and determining the completion of calibration according to the present invention. Detailed Implementation

[0011] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings.

[0012] The following specific examples illustrate the implementation of this disclosure. Those skilled in the art can easily understand other advantages and effects of this disclosure from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. This disclosure can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this disclosure. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0013] Example 1 This embodiment provides a remote configuration and scheduling method for electronic test instruments, aiming to solve the problems of zero-point residual voltage drift, core operating point offset, and easy entry into saturation branches caused by inconsistent historical magnetization states of the magnetic core and improper combination of compensation excitation phase and amplitude during remote calibration of electronic test instruments. When the remote scheduling platform coordinates the control of the programmable current source, zero flux compensation winding, and fluxgate sensor, the current operating point of the magnetic core is not in the same initial state every time it is started. The injection effect of compensation excitation is not only affected by the compensation excitation amplitude, but also has a coupling relationship with the excitation start phase and the current equivalent magnetization depth of the magnetic core. If the compensation command is directly issued based on fixed compensation parameters or a single residual voltage feedback, the compensation excitation may be applied without recognizing the critical saturation state of the magnetic core, making it impossible for the zero-point residual voltage to return stably and amplifying the subsequent measurement error. This embodiment obtains the compensation excitation amplitude, excitation start phase, zero-point residual voltage, and core operating point offset, and determines the current equivalent magnetization depth of the core. It then performs correlation analysis on the coupling response between the current equivalent magnetization depth and the excitation start phase to the zero-point residual voltage and the core operating point offset, identifying the saturation drift excitation timing induced by the coupling between the excitation start phase and the current equivalent magnetization depth. Based on the saturation drift excitation timing, it determines the critical combination of excitation start phase and compensation excitation amplitude that triggers saturation drift at different magnetization depths and generates a compensation injection judgment criterion. The current combination of excitation start phase and compensation excitation amplitude is compared according to the compensation injection judgment criterion. When the critical combination is exceeded, the compensation excitation amplitude and excitation start phase are adjusted to a safe range, obtaining the adjusted compensation excitation parameters. Compensation injection is performed according to the adjusted compensation excitation parameters, and the compensated zero-point residual voltage and noise floor level are collected. A calibration completion marker is output when the zero-point residual voltage returns to a preset threshold and the noise floor level is lower than the measurement tolerance value. Figures 1 to 3 As shown, the method specifically includes the following steps: S1, obtain the compensation excitation amplitude, excitation start phase, zero-point residual voltage and core operating point offset, and determine the current equivalent magnetization depth of the core.

[0014] The remote scheduling platform sends a low-disturbance detection excitation command to the programmable current source. The amplitude of the low-disturbance detection excitation is smaller than the compensation excitation amplitude and operates in the linear segment of the hysteresis loop. The programmable current source injects the low-disturbance detection excitation into the zero-flux compensation winding according to the command. The fluxgate sensor synchronously acquires the response curve of the core operating point offset changing over time. The slope of the response curve near the zero-crossing point is calculated to obtain the zero-crossing slope of the operating point. The zero-crossing slope of the operating point is matched with a pre-stored slope-magnetization depth mapping table to obtain the magnetization depth level. The compensation excitation amplitude, excitation start phase, zero-point residual voltage, core operating point offset, and magnetization depth level are synchronously aligned according to the acquisition time.

[0015] In scenarios involving remote configuration and scheduling of electronic test instruments, the hysteresis loop position of the magnetic core is not the same every time it is started due to differences in its historical magnetization state. If conventional compensation excitation is applied directly, it is impossible to determine whether the magnetic core is currently in a state that is easily pushed into the saturation branch. Therefore, it is necessary to first use low-disturbance excitation to initially detect the differential characteristics of the current operating point, and use the local slope of the operating point near zero magnetic flux as the basis for inferring the current equivalent magnetization depth of the magnetic core, so as to avoid the operating point jump caused by introducing a large excitation.

[0016] Specifically, the typical excitation amplitude for low-disturbance detection is 5mA, estimated based on 1 / 3 of the upper limit of the linear segment current determined by the BH curve test of the magnetic core, and can be adjusted within the range of 1mA to 15mA according to the magnetic core model and transformer specifications; the excitation start phase is sampled in steps within the range of 0° to 360°, with a typical phase step size of 5°, estimated based on the empirical phase width of 10° to 30° according to the non-monotonic characteristics of the hysteresis loop, and covering at least 2 sampling points according to the narrowest phase characteristic, and can be adjusted within the range of 1° to 5°; the typical sampling frequency of the fluxgate sensor is 10kHz, determined based on the low-disturbance excitation fundamental frequency of 50Hz to 1kHz and with a 10-fold margin reserved according to the Nyquist theorem, and can be adjusted within the range of 5kHz to 100kHz; the typical single-point acquisition duration is 200ms, determined based on covering at least 10 complete excitation cycles and taking into account the transmission delay of the remote link, and can be adjusted within the range of 50ms to 2s.

[0017] The output voltage of the fluxgate sensor is converted into the magnetic flux density offset of the core operating point offset using its factory calibration coefficient. The formula for calculating the zero-crossing slope of the operating point is as follows:

[0018] Where B(·) is the operating point offset response curve characterized by magnetic induction intensity, in nanotesla (nT); t z The time when the response curve crosses zero offset is measured in seconds (s); Δt represents the differential time window before and after the zero-crossing point, also measured in seconds (s); k is measured in nanoteslas per second (nT / s), which physically represents the instantaneous rate of change of the operating point offset at the zero-crossing point and can be used as a proportional indicator positively correlated with the differential permeability level at the zero flux point of the magnetic core. The typical value of the differential time window Δt is 100 μs, determined based on the single-step sampling interval corresponding to a sampling frequency of 10 kHz, and can be adjusted within the range of 20 μs to 500 μs.

[0019] In one embodiment, the slope-magnetization depth mapping table is divided into 5 levels according to the magnetization depth level, corresponding to the equivalent magnetization depths L1 to L5 respectively, where L1 indicates that the operating point is far from the saturation branch and the magnetic core is approximately near the initial magnetization curve, and L5 indicates that the operating point is close to the saturation inflection point; the slope thresholds for each level are k≥k0, 0.6k0≤k<k0, 0.3k0≤k<0.6k0, 0.1k0≤k<0.3k0, and k<0.1k0 respectively. The reference slope k0 typically takes a value of 1.5 nT / s, which is calculated based on the zero-crossing slope under no-load conditions during factory production and the initial permeability of the selected magnetic core material, and can be recalibrated within the range of 0.5 nT / s to 5 nT / s. The current equivalent magnetization depth record of the magnetic core after synchronous alignment is stored in the form of a five-tuple (I c , φ, vz, Boff, L), where I c is in milliamperes (mA), φ is in degrees (°), v z is in microvolts (μV), B off is in nanoteslas (nT), and L is dimensionless, serving as the standard input for subsequent coupling response analysis.

[0020] S2. According to the current equivalent magnetization depth of the magnetic core and the excitation starting phase, perform a correlation analysis on the coupling response between the zero residual voltage and the offset of the magnetic core operating point, and identify the saturation drift excitation timing induced by the coupling of the excitation starting phase and the current equivalent magnetization depth of the magnetic core.

[0021] Arrange the zero residual voltage samples in ascending order of the excitation starting phase to obtain an ordered sequence of phase and residual voltage. Take the first-order difference of the zero residual voltage of adjacent samples and use the sign change of the adjacent difference values as the sign change points. Mark the continuous phase segments between adjacent sign change points as candidate non-monotonic response intervals, and remove the sample segments with residual voltage amplitudes lower than the noise threshold to obtain the non-monotonic change characteristics of the residual voltage. Extract multiple groups of compensation excitation amplitude samples and the offset samples of the magnetic core operating point synchronously collected within the phase interval corresponding to the non-monotonic change characteristics of the residual voltage, arrange them in ascending order of the compensation excitation amplitude, and detect the sample segments where the absolute value of the offset of the magnetic core operating point increases synchronously while the compensation excitation amplitude increases and mark them as offset reversal response segments. Bin the offset reversal response segments according to the level of the current equivalent magnetization depth of the magnetic core, perform distribution density statistics on each level bin, and when the distribution density of a certain magnetization depth level bin exceeds the preset saturation determination density threshold, mark the combination of the excitation starting phase and the compensation excitation amplitude corresponding to the offset reversal response segments within the bin as the saturation drift excitation timing.

[0022] In scenarios where the residual voltage is conventionally considered to change monotonically with the initial phase of excitation, the differences in the historical magnetization state of the core cause a non-monotonic inflection point between the phase and the residual voltage. Furthermore, when the compensation excitation amplitude increases, the offset of the operating point, which should return to the zero flux point, actually deepens in the opposite direction after the amplitude critical point. The aforementioned non-monotonic inflection point and offset reversal phenomenon are both early characteristics of the operating point entering the saturation branch of the hysteresis loop. Since the saturation branch entry position varies significantly under different magnetization depths, it is necessary to categorize the saturation drift by magnetization depth level and then distinguish between phase-induced and magnetization depth-induced saturation drift by distribution density.

[0023] Specifically, the noise threshold is typically set to 3σ0, where σ0 is the standard deviation of the residual voltage at a single point obtained by repeatedly sampling the same phase 5 times. The typical value of σ0 is 0.5μV, determined statistically based on the noise floor level of the measurement channel, and can be adjusted within the range of 2σ0 to 5σ0. The criterion for determining the offset reversal response segment is as follows: for adjacent sample pairs arranged in ascending order of compensation excitation amplitude, if the amplitude is larger, the absolute value of the operating point offset is also larger, and the sample pair is included in the candidate segment; the minimum segment length threshold is typically set to 5 consecutive sampling points, determined based on the typical amplitude width of the saturated branch inflection point of 2.5mA to 5mA under an amplitude scan step size of 0.5mA, and can be adjusted within the range of 3 to 10 sampling points; the amplitude scan step size is typically set to 0.5mA, based on the minimum controllable resolution of 0.1mA in the factory parameters of the programmable current source and with a margin of 5 times, and can be adjusted within the range of 0.1mA to 2mA.

[0024] In one embodiment, candidate offset inversion response segments are repeatedly verified over multiple acquisition cycles. The typical acquisition cycle is 1 second, determined based on the average round-trip time of the remote link command-response of approximately 200 ms with a 5-fold margin, and can be adjusted within the range of 0.5 s to 5 s. The stability frequency is calculated as the ratio of the number of occurrences to the total number of cycles, with a typical stability threshold of 0.6, determined based on the statistical upper limit of the probability of random occurrence of pseudo-inversion segments caused by noise, and can be adjusted within the range of 0.4 to 0.8. Occasional segments with stability frequencies below the threshold are eliminated, and the remaining candidate segments are merged according to the criterion that the amplitude gap between adjacent segments does not exceed twice the amplitude scanning step size to obtain the offset inversion response segments.

[0025] The distribution density statistics are performed on the offset reversal response segments of each bucket level. The distribution density statistics formula is as follows:

[0026] Where ρL is the distribution density of the Lth level bucket, expressed in units of segment (°·mA). -1 N L SL represents the number of offset inversion response segments within the bucket, in segments; SL represents the effective coverage area of ​​the bucket on the phase-amplitude plane, in °·mA. The typical saturation threshold is 0.045 segments·(°·mA).-1 Based on the statistical distribution of historical operating data, the average density of the reversal segment within the normal magnetization depth barrel is determined to be 0.015 segments·(°·mA). -1 Take three times that value to determine the range, which can be found in the range of 0.02 to 0.10 (°·mA). -1 Adjustments can be made within the specified range.

[0027] Furthermore, for ρ L For buckets exceeding the saturation density threshold, extract the phase center φ of all inversion segments within the bucket. c With amplitude center I (c,c) As representative points, the phase center and amplitude center are obtained by weighted averaging of each sample in the reversal segment with the stability frequency within the segment as the weight. The representative point set is output according to level L as the saturation drift excitation timing, and is organized into five levels from L1 to L5, with no mixing between levels.

[0028] S3. Based on the saturation drift excitation timing, determine the critical combination of the excitation start phase and the compensation excitation amplitude that triggers saturation drift at different magnetization depths, and generate a compensation injection judgment criterion.

[0029] The saturation drift excitation timings are categorized according to the current equivalent magnetization depth of the magnetic core, resulting in subsets of saturation drift excitation timings at each magnetization depth level. Within each subset at each magnetization depth level, a two-dimensional distribution is constructed using the excitation start phase and compensation excitation amplitude as coordinate axes. The boundary contour between saturation drift excitation timings and non-saturation drift excitation timings is extracted from the two-dimensional distribution. The combination point sequence of critical excitation start phase and critical compensation excitation amplitude is obtained by sampling along the boundary contour. The combination point sequences at each magnetization depth level are then summarized to form a lookup reference table.

[0030] Before applying the compensation excitation, it is necessary to know in advance which combinations of excitation start phase and compensation excitation amplitude are in the critical state of just entering the saturation branch under the current magnetization depth level. The boundary on the phase-amplitude plane must be drawn based on the collected saturation drift excitation timing, so that the subsequent real-time comparison is transformed into a table lookup and boundary judgment operation, avoiding the additional delay caused by re-performing the full-plane density statistics for each calibration.

[0031] Specifically, the two-dimensional distribution uses the excitation start phase φ as the horizontal axis and the compensation excitation amplitude Ic as the vertical axis to determine the saturation drift excitation timing points (φ, Ic) within each level of the bucket. cThe coordinate system is plotted; the boundary contour is extracted using the alpha-shape algorithm, with the alpha parameter typically taking the value 1 / r0, where r0 is the average nearest neighbor distance of the critical point on the phase-amplitude plane, typically taking the value 8 (the plane distance normalized to degrees for phase and milliamperes for amplitude), determined based on the two-dimensional average spacing of representative points within each level bucket, and can be adjusted within the range of 4 to 16; the sampling spacing along the boundary contour typically takes the value 10° along the phase direction and 1mA along the amplitude direction, determined based on the resolution requirements of subsequent critical judgment, and can be adjusted within the ranges of 5° to 30° and 0.5mA to 3mA respectively.

[0032] When discretizing along the boundary contour, a sampling grid is first constructed on the phase-amplitude plane according to the above sampling interval. For each grid node g in the grid... k Boundary Ω L The point closest to it is taken as the corresponding critical combination point. The formula for determining the critical combination point is:

[0033] in Ω L Let g be the boundary of the set of saturation drift excitation opportunities at the Lth magnetization depth level. k Let be the k-th grid node in the sampling grid, dist be the Euclidean distance on the phase-amplitude plane, k be the grid node number, and φ be the distance between the k and k grid nodes. k Unit: degree (°), I (c,k) The unit milliampere (mA) physically represents the combination of the critical excitation start phase and the critical compensation excitation amplitude obtained by discretizing and sampling at the boundary. Traversing all grid nodes in the sampling grid yields the critical combination point sequence for that magnetization depth level. The typical length of the final critical combination point sequence for each magnetization depth level is 36 points (corresponding to a typical sampling interval of 10°). When the sampling interval is adjusted within the range of 5° to 30°, the sequence length varies between 12 and 72 points.

[0034] In one embodiment, the critical combination point sequences at each magnetization depth level are summarized to form a lookup reference table, with the table structure being (L, φ). k , I (c,k) (Boundary direction marker), the boundary direction marker takes the value of "entering saturation" or "leaving saturation", and the resulting compensation injection judgment benchmark is stored in the local database of the remote scheduling platform for low-latency query.

[0035] S4. Based on the compensation injection judgment criteria, the combination of the current excitation start phase and the compensation excitation amplitude is compared. When the critical combination is exceeded, the compensation excitation amplitude and the excitation start phase are adjusted to the safe range to obtain the adjusted compensation excitation parameters.

[0036] In the compensation injection judgment criteria, query the combination point sequence of critical excitation start phase and critical compensation excitation amplitude corresponding to the current magnetic core equivalent magnetization depth level; use the boundary defined by the combination point sequence as a constraint to select candidate safe intervals in the two-dimensional parameter plane of excitation start phase and compensation excitation amplitude; remove candidate safe intervals that intersect with the phase segment marked by the non-monotonic change characteristic of residual voltage; perform deviation calculation on the parameter combination in the remaining candidate safe intervals and the original compensation excitation parameters, select the parameter combination with the smallest deviation, and obtain the adjusted compensation excitation parameters.

[0037] In scenarios where the current combination of compensation excitation parameters is confirmed to be likely to exceed the critical boundary, directly adjusting the parameters significantly will introduce additional disturbances to the measured object and may pull the operating point to the non-monotonic region on the other side. Therefore, it is necessary to find a safe combination with the smallest deviation from the original parameters while satisfying the two constraints of staying away from the saturation boundary and avoiding the non-monotonic phase segment.

[0038] Specifically, the boundary is defined by the sequence of critical combination points. Ω L To constrain the phase-amplitude region on the unsaturated side, it is divided into multiple rectangular candidate windows. The width of each candidate window along the phase direction is typically 15° and the height along the amplitude direction is typically 1.5mA. The adjustment granularity of the phase and amplitude of the subsequent compensation excitation is determined and can be adjusted within the ranges of 5° to 45° and 0.5mA to 3mA, respectively.

[0039] The formula for calculating the deviation is:

[0040] Where (φ, I) c ) represents the parameter combinations within the candidate safe interval, with units of degrees (°) and milliamperes (mA), respectively; (φ0, I (c,0) ) represents the original compensation excitation parameter; φ scale Typical values ​​are 360° and I. scale A typical value of 10mA is used as the normalization scale; w φ with w I φ represents the phase and amplitude deviation weights, both of which are dimensionless; D represents the weighted normalized deviation, which is also dimensionless and physically represents a scalarized measure of parameter migration cost. Typical values ​​for wφ are 0.4 and w... I The typical value is 0.6, which is determined based on the experimental results that the magnetic core is more sensitive to amplitude than phase. It can be adjusted in the ranges of 0.2 to 0.6 and 0.4 to 0.8 respectively, and the sum of the two is kept at 1.

[0041] In one embodiment, for each candidate safe interval, it is first checked whether its phase range intersects with the phase segment recorded by the non-monotonic variation characteristic of residual voltage. If there is an intersection, it is eliminated. For the remaining candidate intervals, the D value of their center point is calculated according to the above deviation formula, and the center point of the candidate interval with the smallest D is selected as the adjusted compensation excitation parameter. Further, the phase distance and amplitude distance between the adjusted compensation excitation parameter and the nearest critical combination point are verified respectively. The typical value of the phase safe distance threshold is 5°, and the typical value of the amplitude safe distance threshold is 0.5mA. It is determined according to the upper limit of the phase and amplitude jitter statistics of the acquisition system, and can be adjusted within the range of 2° to 10° and 0.2mA to 1.5mA respectively. If it does not meet the requirements, the center of the candidate window is shifted away from the boundary until both safe distance thresholds are met simultaneously.

[0042] S5, perform compensation injection according to the adjusted compensation excitation parameters, collect the zero-point residual voltage and noise floor level after compensation, and output a calibration completion mark when the zero-point residual voltage returns to the preset threshold and the noise floor level is lower than the measurement tolerance value.

[0043] The adjusted compensation excitation parameters are sent to the programmable current source, which then injects compensation excitation based on these parameters. The core operating point offset response under the compensation excitation is collected by the fluxgate sensor, and the compensated zero-point residual voltage is calculated synchronously. The root mean square value of the zero-point residual voltage within the preset observation window is used to obtain the noise level. When the zero-point residual voltage returns to the preset threshold and the noise level is lower than the measurement tolerance, a calibration completion mark is output; otherwise, the iteration backoff branch is entered.

[0044] In scenarios where a single compensation injection may not be able to completely return the operating point to the zero flux point due to the combined effect of remote excitation sequence and the historical magnetization state of the magnetic core, it is necessary to verify the residual voltage and noise floor after compensation in real time within the closed loop, and provide a failure rollback mechanism to return to the previous step and reselect a safe range for cases that do not meet the standards.

[0045] Specifically, the typical value of the zero-point residual voltage return preset threshold is 5μV, which is determined based on the engineering requirements for zero-point stability in small current measurement scenarios and the basic resolution of the fluxgate sensor of 2μV. It can be adjusted within the range of 2μV to 20μV. The typical value of the noise floor level measurement tolerance is 3μV, which is determined based on the upper limit of the noise floor statistics allowed by the subsequent small current measurement channel. It can be adjusted within the range of 1μV to 10μV.

[0046] The formula for calculating the noise floor level is:

[0047] Where v (z,i) σ represents the residual voltage sample at the i-th zero point within the preset observation window, in microvolts (μV); M represents the total number of samples within the observation window;n The noise floor level, measured in microvolts (μV), is physically represented by the root mean square value of the zero-point residual voltage within the observation window, characterizing the background amplitude level of zero-point fluctuations. The typical observation window length is 1 second, determined based on the lowest frequency of interest (1Hz) of the measured small current signal and ensuring coverage of at least one complete cycle; it can be adjusted from 0.2s to 10s. The total number of samples M within the window is obtained by multiplying the observation window length by the sampling frequency, with a typical value of 10000.

[0048] In one embodiment, when the zero-point residual voltage returns to the preset threshold and the noise floor level is lower than the measurement tolerance, a calibration completion mark is output, and the adjusted compensation excitation parameters and the corresponding magnetization depth level are written back to the lookup reference table as priority candidates for subsequent calibrations of the same level. When any condition is not met, the iteration backtracking branch is entered: returning to S4, the parameter combination that failed this time is temporarily removed from the candidate safe interval set, the center point of the candidate interval with the second smallest D value is selected as the new adjusted compensation excitation parameter, and S5 is re-executed. The upper limit of the number of single calibration iterations is typically 5 times, which is determined based on the upper limit of the allowable duration of a single remote calibration of 30s and approximately 6s per iteration, and can be adjusted within the range of 3 to 10 times.

[0049] Furthermore, when the number of iterations exceeds the upper limit and still fails to meet the standard, a full-process rollback mechanism is triggered: first, rollback to S1, re-acquire the operating point response curve and refresh the magnetization depth level with a low-disturbance detection excitation amplitude reduced to 50% of the original value, and then re-execute S2 to S5 in sequence; if the standard is still not met after three consecutive full-process rollbacks, report an offline core reset alarm to the remote scheduling platform and save the current five-tuple data snapshot, waiting for manual intervention to reset the core magnetization state, ensuring that the calibration process has a definite termination condition under any abnormal situation.

[0050] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. The present invention has been described in detail with reference to preferred embodiments. Those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications and substitutions should be covered within the scope of the claims of the present invention.

[0051] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0052] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between apparatuses or units through some interfaces, and may be electrical, mechanical, or other forms.

[0053] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0054] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0055] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this 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. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

Claims

1. A method for remote configuration and scheduling of electronic testing instruments, characterized in that, include: Obtain the compensation excitation amplitude, excitation start phase, zero-point residual voltage and core operating point offset, and determine the current equivalent magnetization depth of the core; Based on the current equivalent magnetization depth of the magnetic core and the excitation start phase, a correlation analysis is performed on the coupling response between the zero-point residual voltage and the magnetic core operating point offset to identify the saturation drift excitation timing induced by the coupling between the excitation start phase and the current equivalent magnetization depth of the magnetic core. Based on the saturation drift excitation timing, the critical combination of the excitation start phase and the compensation excitation amplitude that trigger saturation drift at different magnetization depths is determined, and a compensation injection judgment criterion is generated. Based on the compensation injection judgment criteria, the combination of the current excitation start phase and the compensation excitation amplitude is compared. When the critical combination is exceeded, the compensation excitation amplitude and the excitation start phase are adjusted to a safe range to obtain the adjusted compensation excitation parameters. Compensation injection is performed according to the adjusted compensation excitation parameters. The zero-point residual voltage and noise floor level after compensation are collected. A calibration completion mark is output when the zero-point residual voltage returns to the preset threshold and the noise floor level is lower than the measurement tolerance value.

2. The method according to claim 1, characterized in that, The process of obtaining the compensation excitation amplitude, excitation start phase, zero-point residual voltage, and core operating point offset, and determining the current equivalent magnetization depth of the core, specifically includes: The low-disturbance detection excitation command is issued through the remote scheduling platform. The amplitude of the low-disturbance detection excitation is smaller than that of the compensation excitation and it operates in the linear section of the hysteresis loop. A low-disturbance detection excitation is injected by a programmable current source according to the low-disturbance detection excitation command, and the response curve of the magnetic core operating point offset changing with time is synchronously collected by a fluxgate sensor; The slope of the response curve near the zero-crossing point is calculated to obtain the zero-crossing slope of the operating point; The zero-crossing slope of the operating point is matched with the pre-stored slope and the magnetization depth mapping table to obtain the magnetization depth level. The compensation excitation amplitude, excitation start phase, zero-point residual voltage, core operating point offset, and magnetization depth level are synchronously aligned according to the acquisition time to obtain the current equivalent magnetization depth of the core.

3. The method according to claim 1, characterized in that, The correlation analysis of the coupling response between the zero-point residual voltage and the core operating point offset specifically includes: Arrange the zero-point residual voltage samples in ascending order according to the excitation start phase to obtain an ordered sequence of phase and residual voltage; Perform a first-order difference operation on the ordered sequence of phase and residual voltage, detect the sign change points of the residual voltage difference value, and mark the continuous phase segment between adjacent sign change points as candidate non-monotonic response intervals; Sample segments with residual voltage amplitudes below the noise threshold within the candidate non-monotonic response interval are eliminated to obtain the non-monotonic variation characteristics of the residual voltage.

4. The method according to claim 3, characterized in that, The identification of the saturation drift excitation timing induced by the coupling between the excitation start phase and the current equivalent magnetization depth of the core specifically includes: Multiple sets of compensation excitation amplitude samples and core operating point offset samples acquired synchronously are extracted within the phase interval corresponding to the non-monotonic variation characteristics of the residual voltage. The samples are arranged in ascending order of the compensation excitation amplitude to obtain a pairing sequence of amplitude and offset. The sample segment whose compensation excitation amplitude increases and whose absolute value of the core working point offset increases synchronously is detected. The sample segment whose continuous length exceeds the preset minimum segment length threshold is marked as the offset reversal response segment. The offset inversion response segments are divided into buckets according to the level of the current equivalent magnetization depth of the magnetic core, and the distribution density statistics of the offset inversion response segments in each bucket are performed. When the distribution density of a certain magnetization depth level barrel exceeds the preset saturation judgment density threshold, the combination of the excitation start phase and the compensation excitation amplitude corresponding to the offset reversal response segment within that level barrel is marked as the saturation drift excitation timing.

5. The method according to claim 4, characterized in that, The step of marking sample segments whose duration exceeds a preset minimum segment length threshold as offset inversion response segments specifically includes: The candidate offset inversion response segment is repeatedly verified in multiple acquisition cycles to obtain the occurrence record of the candidate offset inversion response segment in each acquisition cycle; The frequency of occurrence of the records is statistically analyzed to obtain the stability frequency. The occasional segments whose stability frequency is lower than the stability threshold are removed. The retained candidate segments are merged according to the compensation excitation amplitude range to obtain the offset inversion response segment.

6. The method according to claim 1, characterized in that, The step of determining the critical combination of the excitation start phase and the compensation excitation amplitude for triggering saturation drift at different magnetization depths based on the saturation drift excitation timing, and generating a compensation injection judgment criterion, specifically includes: The saturation drift excitation timings are categorized according to the current equivalent magnetization depth of the magnetic core to obtain a subset of saturation drift excitation timings for each magnetization depth level. Within the subset of each magnetization depth level, a two-dimensional distribution is constructed with the excitation start phase and the compensation excitation amplitude as coordinate axes; Extract the boundary profile between saturated drift excitation timing and unsaturated drift excitation timing from the two-dimensional distribution; A sequence of points combining the critical excitation start phase and the critical compensation excitation amplitude is obtained by sampling along the boundary contour. The combination point sequences at each magnetization depth level are summarized to form a query benchmark table, and the compensation injection judgment benchmark is obtained.

7. The method according to claim 3, characterized in that, The step of adjusting the compensation excitation amplitude and the excitation start phase to a safe range to obtain the adjusted compensation excitation parameters specifically includes: In the compensation injection judgment criteria, query the sequence of combination points of critical excitation start phase and critical compensation excitation amplitude corresponding to the current magnetic core equivalent magnetization depth level; Using the boundary defined by the combined point sequence as a constraint, a candidate safe interval is selected in the two-dimensional parameter plane of the excitation start phase and the compensation excitation amplitude; Candidate safe intervals that intersect with the phase segments marked by the non-monotonic variation characteristics of the residual voltage will be eliminated. The parameter combinations in the remaining candidate safe intervals are compared with the original compensation excitation parameters by performing deviation calculations. The parameter combination with the smallest deviation is selected from the remaining candidate safe intervals to obtain the adjusted compensation excitation parameters.

8. The method according to claim 2, characterized in that, The step of performing compensation injection according to the adjusted compensation excitation parameters and collecting the zero-point residual voltage and noise floor level after compensation specifically includes: The adjusted compensation excitation parameters are sent to the programmable current source; The programmable current source injects compensation excitation according to the adjusted compensation excitation parameters; The core operating point offset response under compensated excitation is acquired by a fluxgate sensor. The zero-point residual voltage is obtained by synchronously calculating the response of the magnetic core operating point offset; The root mean square value of the zero-point residual voltage within a preset observation window is calculated to obtain the noise floor level.

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