A calibration method and apparatus for multi-loop diagnostic devices

Abstract

This invention discloses a verification method and apparatus for a multi-loop diagnostic device. The method includes: S1: establishing a unified electrical reference, connecting multiple voltage channels and multiple current channels of the diagnostic device to the meter station according to a preset access scheme, and applying operating conditions; S2: issuing initialization parameters to the diagnostic device according to the actual electrical connection of the diagnostic device; S3: starting data acquisition in the diagnostic device, calculating the electrical parameters of each channel based on the acquired real-time data; S4: issuing calibration instructions and standard values ​​to the diagnostic device, where the standard values ​​are theoretical test data; S5: comparing the calculated electrical parameters of each channel with the received standard values, calculating the calibration coefficient of each channel, and returning to step S2 after calibration is completed; after step S3, in response to not starting calibration, the method further includes: S6: starting meter testing; calculating the power error of each channel and each test condition, which is used as the measurement error of each channel and each test condition.

Description

Technical Field

[0001] This application relates to the field of medium and low voltage power technology, and in particular to a verification method and device for multi-circuit diagnostic devices. Background Technology

[0002] Driven by the energy internet and new digital infrastructure, multi-loop intelligent diagnostic devices have become core equipment for the refined monitoring of medium and low voltage systems, and are widely used in energy consumption management and power analysis in scenarios such as data centers, smart buildings, and distributed photovoltaic power stations. Multi-loop power diagnostic devices have certain requirements for metering accuracy, typically needing to meet 0.5s or 2s level, and therefore also require calibration.

[0003] Existing calibration methods are mainly applied to electricity meters, requiring phase-by-phase calibration of each channel. For multi-loop power diagnostic devices with multiple current channels, voltage and current channels that are arbitrarily matched, this method is inefficient and cannot guarantee any arbitrary channel matching, thus failing to meet the requirements for efficient calibration. Summary of the Invention

[0004] To address the aforementioned issues, this application provides a calibration method and apparatus for multi-loop diagnostic devices, which improves metering accuracy and enables rapid and accurate calibration of multi-loop power diagnostic devices.

[0005] In a first aspect, embodiments of this application provide a verification method applied to a multi-loop diagnostic device, the method comprising: S1: Establish a unified electrical reference, and according to the preset access scheme, connect multiple voltage channels and multiple current channels of the diagnostic device to the meter platform and apply operating conditions; the operating conditions applied to the meter platform include frequency, effective voltage value, effective current value, and power factor; S2: Based on the actual electrical connection of the diagnostic device, issue initialization parameters to the diagnostic device; the initialization parameters include the rated power grid frequency, rated sampling frequency, the correspondence between the current channel and the voltage channel, and the CT type of the current channel; S3: The diagnostic device starts data acquisition and calculates the electrical parameters of each channel based on the acquired real-time data; the electrical parameters include the effective value of the acquired voltage, the effective value of the acquired current, and the phase; S4: Send a calibration command and standard values ​​to the diagnostic device. The standard values ​​are theoretical test data. The standard values ​​include: current transformer type, effective voltage value, phase between each voltage channel and the target voltage channel, effective current value, and phase between each current channel and the target voltage channel. S5: Compare the electrical parameters calculated from each channel with the received standard values, and calculate the calibration coefficient for each channel. After calibration, return to step S2.

[0006] Preferably, the diagnostic device includes multiple voltage channels and multiple current channels, each current channel is connected to a current transformer, and all current transformers are current transformers of the same type and standard. The access scheme specifically includes: connecting each voltage channel to the same phase of the meter station, and having each current channel collect the current signal of that phase of the meter station through the same current transformer.

[0007] Preferably, step S3 specifically includes: performing gain compensation and phase offset compensation on the acquired real-time data based on the calibration coefficient of the preceding time step, processing the compensated data, and calculating the electrical parameters of each channel.

[0008] Preferably, the acquired real-time data is subjected to gain compensation and phase shift compensation based on the calibration coefficient of the previous moment, specifically including: Obtain the calibration coefficients from the preceding time step, wherein the calibration coefficients include the gain coefficient and the phase compensation value; The real-time data is corrected based on the gain coefficient to obtain gain data; Based on the data cached in the preceding time step and the corresponding phase compensation value, the gain data is phase offset compensation is performed using linear interpolation or quadratic interpolation algorithms to obtain the compensated data.

[0009] Preferably, the compensated data is processed, specifically including: The collected voltage and current data are buffered for N cycles. The N cycles of data are copied M times to form a data sequence of (M*N) cycles; M≥2; The data sequence corresponding to each acquisition channel is filtered, and the last N cycles of the filtered data are taken to calculate the electrical parameters of each channel.

[0010] Preferably, the calculation of the calibration coefficient specifically includes: Upon receiving the calibration command, obtain the calibration coefficients from the previous moment and stop updating the calibration coefficients; Upon receiving the standard value, the electrical parameters of each channel calculated under the calibration coefficient of the previous moment are obtained, the phase difference between each voltage and current channel and the target voltage channel is calculated, and the calculated value is output. The updated value of the calibration coefficient is calculated based on the standard value, the calculated value, and the calibration coefficient of the previous moment. The calibration coefficient is updated based on the updated value and used for the calculation of electrical parameters in step S2.

[0011] Preferably, the method further includes limiting the amplitude of the new calibration coefficient: The limit range of the calculated values ​​of the preset calibration coefficient; Obtain the calculated value of the new calibration coefficient, and determine the accuracy of the calculated value based on the limiting range: If the calculated value does not meet the amplitude limit range, the calibration coefficient is not saved, and recalibration is performed. If the calculated value meets the amplitude limit range, then the new calibration coefficient is saved and the calibration coefficient is updated.

[0012] Preferably, after step S3, in response to not initiating calibration, the method further includes: S6: Start the checklist; specifically includes: The system detects different test conditions applied to the meter platform and reads the active and reactive power values ​​of each channel of the diagnostic device, as well as the active and reactive power values ​​of the standard meter on the meter platform. Calculate the power error for each channel and under each test condition, which will be used as the measurement error for each channel and under each test condition.

[0013] In a second aspect, the present invention also proposes a verification device for a multi-loop diagnostic device, comprising: a processor and a memory, wherein the memory stores a computer program, and the computer program, when executed by the processor, implements the method described in any one of the first aspects above.

[0014] The beneficial effects of this invention are as follows: This invention relates to a verification method and apparatus for multi-circuit diagnostic devices. For multi-circuit power diagnostic devices with arbitrarily matched voltage and current channels, it adopts a single-phase power access method and sends out a minimal number of standard values ​​to achieve amplitude gain calibration and phase offset calibration for all voltage and current channels. By using data copying and filtering, it can effectively suppress the impact of low-frequency fluctuations in meter signals and is compatible with various current transformer types and multiple rated grid frequencies, making it applicable to most power consumption scenarios in various countries.

[0015] This invention, with a real hardware architecture that equips each current channel with an independent CT, enables parallel calibration of all channels without changing the original design of the diagnostic device. Instead, it improves calibration efficiency through ingenious external wiring and internal algorithms.

[0016] By using the two control conditions of "same standard CT" and "same current", the channel error is isolated and located on each independent measurement channel, thereby achieving precise compensation for each channel. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A flowchart illustrating a verification method for a multi-loop diagnostic device provided in this application embodiment; Figure 2 This is a wiring diagram of the calibration process in an embodiment of this application; Figure 3 This is a time-domain waveform diagram of the stable RMS value method in the embodiments of this application; Figure 4 This is an RMS detection graph of the stable RMS method in the embodiments of this application; Figure 5 This is a phase detection diagram of the stable effective value method in the embodiments of this application. Detailed Implementation

[0019] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0020] In the following description, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The following description provides multiple embodiments of this application, which can be substituted or combined with each other. Therefore, this application can also be considered to include all possible combinations of the same and / or different embodiments described. Thus, if one embodiment includes features A, B, and C, and another embodiment includes features B and D, then this application should also be considered to include embodiments containing one or more other possible combinations of A, B, C, and D, even if such embodiments are not explicitly described in the following text.

[0021] The following description provides examples and does not limit the scope, applicability, or examples set forth in the claims. Changes may be made to the function and arrangement of the described elements without departing from the scope of this application. Various processes or components may be appropriately omitted, substituted, or added to the examples. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Furthermore, features described with respect to some examples may be combined into other examples.

[0022] Please see Figure 1 , Figure 1 This is the overall flowchart of the present invention.

[0023] In this embodiment of the application, the method includes: S1. Establish a unified electrical standard and connect multiple voltage channels and multiple current channels of the diagnostic device to the meter station according to the preset access scheme. The operating conditions applied to the meter include frequency, effective voltage value, effective current value, and power factor.

[0024] It is feasible to select a current with a rated frequency of 50Hz, a rated voltage of 220V, half the range of the current transformer, and a power factor of 0.5L.

[0025] The implementing entity of this application can be a multi-loop diagnostic device, which, together with a platform and a host computer, enables rapid and accurate calibration of the multi-loop diagnostic device.

[0026] It should be clarified that the diagnostic device includes multiple voltage channels and multiple current channels. Each current channel is connected to a current transformer, and all current transformers are of the same type and standard.

[0027] Secondly, this application provides a specific access scheme for the diagnostic device, which is as follows: each voltage channel is connected to the same phase of the meter, and each current channel collects the current signal of that phase of the meter through the same current transformer.

[0028] Based on this access scheme, the method of this application is implemented based on the same benchmark and controlled variables. All CT types are identical, and their ideal transformation ratio and frequency characteristics are consistent. Therefore, any differences in the measured values ​​of each current channel when the same current is passed can be accurately attributed to the gain and phase offset errors of the channel itself (including individual differences of CTs and errors of subsequent sampling circuits).

[0029] Please see Figure 2 , Figure 2 The diagram below shows the wiring diagram of the calibration process in this embodiment of the invention. The meter outputs single-phase voltage and single-phase current. The phase line of the meter voltage is connected to the phase line voltage port of the diagnostic device. The meter outputs single-phase current, and the current phase and voltage are the same. The current signal is collected through a current transformer and connected to the current sampling circuit of the diagnostic device. One current transformer connected to one current acquisition channel constitutes one current channel.

[0030] With the above access method, it is not limited by single-phase or three-phase meter stands, and multiple voltage and current simultaneous calibrations can be achieved by inputting a small number of standard values.

[0031] S2. Issue initialization parameters to the diagnostic device based on its actual electrical connections; The initialization parameters include the rated grid frequency, the rated sampling frequency, the correspondence between the current channel and the voltage channel, and the CT type of the current channel.

[0032] In practice, the initialization parameters should include at least the rated grid frequency and the sampling frequency.

[0033] In one possible implementation, the host computer sends operating parameters to the diagnostic device, including the rated power grid frequency, rated sampling frequency, CT type, etc. At the same time, the calibration mode should be specified to switch the operating state. For example, it should be specified that the diagnostic device is currently in single-phase parallel calibration mode, thereby activating subsequent steps, such as expecting to receive simplified standard values ​​(S4) and enabling parallel calibration logic (S5) instead of the traditional phase-by-phase calibration logic.

[0034] After the diagnostic device is connected according to the access scheme, the actual electrical connection of the diagnostic device is a known state or predictable data. Therefore, when the initialization parameters are issued according to the actual electrical connection of the diagnostic device, the initialization parameters can be considered to be relatively fixed based on the determined access scheme.

[0035] Simultaneously, data processing and filter selection can be performed based on the initialization parameters to determine the filter coefficients, so as to facilitate the filtering of the cycle data of each acquisition channel in the subsequent step S3.

[0036] S3. The diagnostic device starts data acquisition and calculates the electrical parameters of each channel based on the acquired real-time data. The electrical parameters include the effective value of the acquired voltage, the effective value of the acquired current, and the phase.

[0037] When calculating electrical parameters, bandpass filtering can be used to avoid instability in the detection results caused by low-frequency (<50Hz) fluctuations and ripple signals.

[0038] Preferably, the acquired real-time data is subjected to gain compensation and phase offset compensation based on the calibration coefficient of the preceding time step, and the compensated data is processed and the electrical parameters of each channel are calculated.

[0039] After the diagnostic device is powered on, the sampling frequency and filter parameters are configured according to the issued rated (grid) frequency (e.g., 50Hz). The acquired raw data is first "pre-compensated," that is, multiplied by the old gain coefficient and then phase interpolation compensation is performed.

[0040] In one possible implementation, gain compensation and phase offset compensation based on the preceding time calibration coefficients are performed on the acquired real-time data, specifically including: Obtain the calibration coefficients from the preceding time step, wherein the calibration coefficients include the gain coefficient and the phase compensation value; The real-time data is corrected based on the gain coefficient to obtain gain data; Based on the data cached in the preceding time step and the corresponding phase compensation value, the gain data is phase offset compensation is performed using linear interpolation or quadratic interpolation algorithms to obtain the compensated data.

[0041] The preceding time step can be specifically the previous 1-2 time steps. Taking the previous time step as an example, the calibration coefficient of the previous time step is obtained. Based on the gain coefficient and phase compensation value of that time step, gain compensation and phase offset compensation are performed on the real-time data of the current time step.

[0042] After obtaining the compensated data, processing can be performed based on the compensated data to suppress the impact of signal fluctuations and the initial transient response of the filter on the calculation accuracy.

[0043] In one feasible embodiment, the compensated data is processed, specifically including: The collected voltage and current data are buffered for N cycles. The N cycles of data are copied M times to form a data sequence of (M*N) cycles; M≥2; The data sequence corresponding to each acquisition channel is filtered, and the last N cycles of the filtered data are taken to calculate the electrical parameters of each channel.

[0044] For example, two cycles of data can be cached, copied 10 times, filtered using an IIR bandpass filter, and the last two stable cycles in the filtered data can be taken. The fundamental RMS value and phase are then calculated using the true RMS algorithm and FFT to obtain the electrical parameters. The electrical parameters are calculated based on real-time data acquired by the diagnostic device.

[0045] Please see Figure 3 , Figure 3 The image shows the time-domain waveform of the stable RMS value method in this embodiment of the invention. The data is composed of a 50Hz signal with an RMS value of 10 and a 7Hz signal with an RMS value of 0.2 (low-frequency signal interference). As shown in the first part, the signal envelope fluctuates due to the superposition of the 7Hz signal. After IIR filtering, as shown in the second part, the signal tends to be stable and there is no obvious envelope.

[0046] Please see Figure 4 , Figure 4 The diagram shows the effective value detection of the stable effective value method in this embodiment of the invention. As shown in the previous section, before data filtering, the effective value of the signal fluctuates, with a maximum amplitude of about 2‰. If this result is used for calibration, or if the low-frequency signal interference is more severe, the calibrated result will have a certain deviation. After IIR filtering, as shown in the later section, the calculated effective value of the signal is stable, and the error between it and the true value is extremely small.

[0047] Please see Figure 5, Figure 5 The phase detection diagram of the stable effective value method in this embodiment of the invention shows that, as shown in the first part, the phase of the signal fluctuates, with a phase fluctuation exceeding 0.002 rad, or more than 0.1 degrees. For the operating condition with a power factor < 0.5, a phase angle error of 0.1 degrees will introduce an error of more than 3‰. After IIR filtering, as shown in the second part, the phase detection result tends to be stable, with a fluctuation range of less than 0.01 degrees, which can achieve more accurate phase calibration.

[0048] S4. Send calibration instructions and standard values ​​to the diagnostic device. The standard values ​​are theoretical test data. The standard values ​​include: current transformer type, effective voltage value, phase between each voltage channel and the target voltage channel, effective current value, and phase between each current channel and the target voltage channel.

[0049] Under the access scheme of this application, the host computer only needs to input five parameters to realize the calibration of multiple channels, namely, the current transformer type, the effective value of the actual voltage measured on the meter, the effective value of the actual current measured on the meter, the angle between the same voltage, and the phase between the actual voltage and current measured on the meter.

[0050] These five parameters correspond to the standard values. Among them, each voltage channel and the target voltage channel have the same voltage, and the phase angle should be 0.

[0051] After receiving the standard value, the diagnostic device compares it with the actual measured value of each channel to obtain the deviation of each channel. The actual measured value can be obtained based on the electrical parameters in step S3.

[0052] S5. Compare the electrical parameters calculated for each channel with the received standard values, and calculate the calibration coefficient for each channel. After calibration, return to step S2.

[0053] In the embodiments of this application, based on the deviation between the measured value / electrical parameter and the standard value, a new gain coefficient and phase compensation value for each channel can be calculated in parallel using a preset algorithm (e.g., proportional calculation), thereby obtaining a new calibration coefficient for subsequent calculation of electrical parameters.

[0054] In one specific embodiment, the calculation of the calibration coefficient includes: Upon receiving a calibration command, retrieve the calibration coefficients from the previous moment and stop updating the calibration coefficients; Upon receiving the standard value, the electrical parameters of each channel calculated under the calibration coefficient of the previous moment are obtained, the phase difference between each voltage and current channel and the target voltage channel is calculated, and the calculated value is output. The updated value of the calibration coefficient is calculated based on the standard value, the calculated value, and the calibration coefficient of the previous moment. The calibration coefficients are updated based on the updated values ​​and used for the calculation of electrical parameters in step S2.

[0055] After updating the calibration coefficients, new calibration coefficients are obtained. These new calibration coefficients are used for the calculation of electrical parameters in the next round. That is, we can return to step S2 to perform the calculation of electrical parameters in the next round.

[0056] For new calibration coefficients, a limit judgment can be performed to ensure their rationality. If they are rational, they can be saved and updated for subsequent measurements; if they are not rational, an error will be reported and a recalibration request will be made.

[0057] In one feasible embodiment, the limiting determination of the new calibration coefficient specifically includes: The limit range of the calculated values ​​of the preset calibration coefficient; Obtain the calculated values ​​of the new calibration coefficients, and determine the accuracy of the calculated values ​​based on the limiting range: If the calculated value does not meet the limit range, the calibration coefficient will not be saved, and recalibration will be performed. If the calculated value meets the limit range, save the new calibration coefficient and update the calibration coefficient.

[0058] Specifically, a reasonable limiting range can be set (such as gain ±20%, phase ±5°). If the new coefficient exceeds the limit, it is judged as calibration failure (possibly due to wiring errors or signal abnormalities), triggering an alarm and refusing to update, thus preventing "false calibration".

[0059] For example, the reasonable range for the gain coefficient is set to [0.8, 1.2]. If the new gain coefficient calculated for a channel is 1.25, the channel is considered to have an abnormal calibration, the process is terminated, and an error is reported. If all coefficients are normal, the new coefficients are saved and enabled.

[0060] S6. Start the checklist.

[0061] Following step S3, in response to not initiating calibration, the check is initiated, specifically including: The instrument detects different test conditions applied to the instrument platform and reads the active and reactive power values ​​of each channel of the diagnostic device, as well as the active and reactive power values ​​of the standard meter on the instrument platform. Calculate the power error for each channel and under each test condition, which will be used as the measurement error for each channel and under each test condition.

[0062] One of the conditions for not initiating calibration should be that after calibrating each channel in the diagnostic device, the calibration effect needs to be verified.

[0063] After the calibration of each channel in the diagnostic device is completed, after step S3, the calibration can be stopped and step S6 can be executed to start the test table to verify the calibration effect, thereby obtaining the measurement error of each channel under each test condition.

[0064] In a preferred embodiment, after completing the calibration of each channel of the diagnostic device, after step S3, the calibration is not started, but the test meter is started to verify the calibration effect. The host computer controls the test meter to go through a series of typical operating conditions, record and compare the power readings of the diagnostic device and the standard meter, and finally generate a detailed error report to intuitively verify the calibration effect of the present invention.

[0065] After step S3, if calibration is initiated, in step S4, the host computer sends a calibration command and standard value to the diagnostic device; when the diagnostic device receives the calibration command, it initiates calibration and executes step S4.

[0066] It should be clarified that the initiation of calibration does not depend on the data acquisition and calculation process itself, but is an "external event" determined by external quality, internal state, and preset conditions. Among them, the basic conditions for continuous operation during data acquisition and calculation provide the necessary data preparation for calibration; while calibration is a triggered, non-periodic process.

[0067] In specific implementation, the following methods can be used to determine when to initiate calibration: Firstly, external explicit commands are preferred, such as calibration commands issued by a host computer. This method offers clear control, simple logic, and high reliability.

[0068] For example, a calibration command can be issued to the host computer by an operator or an automated test script.

[0069] Specifically, the operator observes the host computer software interface to confirm that the voltage, current, frequency, and power factor output by the meter have reached the target values ​​and remain stable. Then, the operator manually clicks the "Start Calibration" button.

[0070] Specifically, in an automated production line, after the output of the control panel stabilizes, the control computer (host computer) automatically waits for a preset stabilization time (such as 10 seconds), and then automatically sends a "calibration command" to the device through a communication protocol (such as Modbus-TCP, GPIB, etc.).

[0071] An exemplary implementation step may be as follows: The diagnostic device continuously acquires and calculates data (S3); the host computer (or operator) sends a specific "calibration instruction" command frame to the device after determining that the table's operating condition has stabilized; upon receiving this command, the diagnostic device immediately enters the calibration preparation state (e.g., obtains the calibration coefficients from the previous moment and stops updating the calibration coefficients).

[0072] Secondly, internal state and condition triggering (assisted or automatic methods) has a higher degree of automation and reduces human intervention; however, the corresponding logic is more complex, and thresholds and judgment conditions should be carefully set to avoid false triggering.

[0073] For example, the calibration command may be triggered by the firmware logic inside the diagnostic device or the intelligent logic of the host computer.

[0074] Specifically, based on the continuously calculated S3 data, the stability of the operating conditions is first determined, and then the calibration process is triggered according to preset conditions. In practical implementation, self-calibration after power-on or reset can also be considered.

[0075] An example of the determination logic is as follows: The diagnostic device or host computer continuously monitors and calculates the effective values ​​of voltage and current. When the fluctuation of these values ​​is less than a preset threshold (e.g., 0.02%) within several consecutive calculation cycles (e.g., 5 cycles), the operating condition is considered stable, and calibration is automatically triggered. A series of calibration points (e.g., 100%Ib, 50%Ib, 10%Ib...) can be preset in the host computer. When the control panel output switches to a certain calibration point and stabilizes, the host computer automatically compares the current operating condition with the target calibration point. If a match is found, the calibration process for that calibration point is automatically triggered.

[0076] Secondly, after the device is powered on for the first time or after a software reset, it can automatically start a calibration process to obtain an initial and accurate calibration coefficient. If the device has a built-in temperature sensor, it can automatically trigger calibration to compensate for temperature drift when it detects that the ambient temperature change exceeds a certain range.

[0077] Therefore, the above judgment logic can be integrated into steps S3 and S4, combining external triggers and internal judgments to make the inspection process more complete, as detailed below: While executing step S3 (starting data acquisition and calculation), a monitoring loop is executed in parallel: The diagnostic device firmware continuously calculates and updates the electrical parameters of each channel; These real-time data are periodically and proactively reported to the host computer via communication interfaces (such as Ethernet, data cables, etc.) or queried by the host computer.

[0078] The host computer is responsible for the core judgment. These data are displayed in real time on the host computer interface, allowing operators to see whether the data is stable. At the same time, the internal program of the host computer is also monitoring the stability of the data (volatility < threshold).

[0079] When the triggering conditions are met, the host computer sends a calibration command and standard value to the diagnostic device. After receiving the calibration command, the diagnostic device obtains the calibration coefficients from the previous moment and stops updating the calibration coefficients. It uses the latest effective value and phase value (electrical parameters in S3) calculated under the currently used old calibration coefficients as the calculation value to complete the calculation and update of the calibration coefficients.

[0080] The triggering conditions include: Method A (Manual Confirmation): The operator observes that the data on the host computer interface is stable and then manually clicks "Calibrate".

[0081] Method B (Automatic Confirmation): The host computer program determines that the data is stable and matches the current preset calibration point.

[0082] It should be clarified that the calibration command is issued by the host computer after confirming that the output of the instrument is stable, or the calibration command is automatically triggered by the diagnostic device or the host computer after monitoring that the electrical parameter data is stable, so as to realize a triggering mechanism based on external triggering and selectively combined with internal stability judgment.

[0083] According to a second aspect of the present invention, a verification device for use in a multi-loop diagnostic device is provided, comprising: a processor and a memory, wherein a computer program is stored in the memory, and the computer program, when executed by the processor, implements the method described in the first aspect.

[0084] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, as some steps may be performed in other orders or simultaneously according to this application. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to this application.

[0085] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0086] Those skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, which may include: a flash drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, etc.

[0087] The foregoing description is merely an exemplary embodiment of this disclosure and should not be construed as limiting the scope of this disclosure. Any equivalent changes and modifications made in accordance with the teachings of this disclosure shall still fall within the scope of this disclosure. Those skilled in the art will readily conceive of embodiments of this disclosure upon considering the specification and practicing the disclosure herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not described herein. The specification and embodiments are to be considered exemplary only, and the scope and spirit of this disclosure are defined by the claims.

Claims

1. A verification method for multi-loop diagnostic devices, characterized in that, The method includes: S1: Establish a unified electrical reference, and according to the preset access scheme, connect multiple voltage channels and multiple current channels of the diagnostic device to the meter platform and apply operating conditions; the operating conditions applied to the meter platform include frequency, effective voltage value, effective current value, and power factor; S2: Based on the actual electrical connection of the diagnostic device, issue initialization parameters to the diagnostic device; the initialization parameters include the rated power grid frequency, rated sampling frequency, the correspondence between the current channel and the voltage channel, and the CT type of the current channel; S3: The diagnostic device starts data acquisition and calculates the electrical parameters of each channel based on the acquired real-time data; the electrical parameters include the effective value of the acquired voltage, the effective value of the acquired current, and the phase; S4: Send a calibration command and standard values ​​to the diagnostic device. The standard values ​​are theoretical test data. The standard values ​​include: current transformer type, effective voltage value, phase between each voltage channel and the target voltage channel, effective current value, and phase between each current channel and the target voltage channel. S5: Compare the electrical parameters calculated for each channel with the received standard values, and calculate the calibration coefficient for each channel. After calibration, return to step S2. The diagnostic device includes multiple voltage channels and multiple current channels. Each current channel is connected to a current transformer, and all current transformers are of the same type and standard. The access scheme specifically includes: connecting each voltage channel to the same phase of the meter station, and collecting the current signal of that phase of the meter station through the same current transformer for each current channel; Step S3 specifically includes: performing gain compensation and phase offset compensation on the collected real-time data based on the calibration coefficient of the preceding time step, processing the compensated data and calculating the electrical parameters of each channel. Specifically, the real-time data collected is subjected to gain compensation and phase offset compensation based on the calibration coefficients of the preceding time step, including: Obtain the calibration coefficients from the preceding time step, wherein the calibration coefficients include the gain coefficient and the phase compensation value; The real-time data is corrected based on the gain coefficient to obtain gain data; Based on the data cached in the preceding time step and the corresponding phase compensation value, the gain data is phase offset compensation is performed using linear interpolation or quadratic interpolation algorithm to obtain the compensated data; The processing of the compensated data specifically includes: The collected voltage and current data are buffered for N cycles. The N cycles of data are copied M times to form a data sequence of (M*N) cycles; M≥2; The data sequence corresponding to each acquisition channel is filtered, and the last N cycles of the filtered data are taken to calculate the electrical parameters of each channel.

2. The method according to claim 1, characterized in that, The calculation of the calibration coefficient specifically includes: Upon receiving the calibration command, obtain the calibration coefficients from the previous moment and stop updating the calibration coefficients; Upon receiving the standard value, the electrical parameters of each channel calculated under the calibration coefficient of the previous moment are obtained, the phase difference between each voltage and current channel and the target voltage channel is calculated, and the calculated value is output. The updated value of the calibration coefficient is calculated based on the standard value, the calculated value, and the calibration coefficient of the previous moment. The calibration coefficient is updated based on the updated value and used for the calculation of electrical parameters in step S3.

3. The method according to claim 2, characterized in that, This also includes limiting the new calibration coefficients: The limit range of the calculated values ​​of the preset calibration coefficient; Obtain the calculated value of the new calibration coefficient, and determine the accuracy of the calculated value based on the limiting range: If the calculated value does not meet the amplitude limit range, the calibration coefficient is not saved, and recalibration is performed. If the calculated value meets the amplitude limit range, then the new calibration coefficient is saved and the calibration coefficient is updated.

4. The method according to claim 1, characterized in that, Following step S3, in response to not initiating calibration, the method further includes: S6: Start the checklist; specifically includes: The system detects different test conditions applied to the meter platform and reads the active and reactive power values ​​of each channel of the diagnostic device, as well as the active and reactive power values ​​of the standard meter on the meter platform. Calculate the power error for each channel and under each test condition, which will be used as the measurement error for each channel and under each test condition.

5. The method according to claim 4, characterized in that, In step S4, a calibration command and standard value are sent to the diagnostic device via a host computer. When the diagnostic device receives the calibration command, it starts the calibration and executes step S4.

6. A calibration device for use in multi-loop diagnostic devices, characterized in that, include: A processor and a memory, wherein a computer program is stored in the memory, and the computer program, when executed by the processor, implements the method as described in any one of claims 1-5.

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