Self-calibration method and system based on intelligent measurement switch function

Abstract

This invention discloses a self-calibration method and system based on the metrological function of an intelligent measurement switch, relating to the fields of electrical variable measurement and magnetic variable measurement technology. The specific steps of the method are as follows: In a standard metrological test environment, the inherent step electrical signal of the contact pre-breakdown is collected as the sole calibration benchmark; parameters are extracted to construct a full-condition benchmark library and encrypted for read-only storage; real-time signals are synchronously acquired during equipment operation with phase-locked loop, and orthogonal decomposition is used to purify and match benchmark features; combined with multi-physics parameters, errors are separated through a decoupling model, and amplitude and phase errors are calculated; calibration coefficients are generated and transmitted via a verification bus; calibration verification and fault tolerance processing are completed through dual-channel verification. This invention achieves in-situ calibration without shutdown by using the inherent signal of the device as a benchmark and encrypting its storage; multi-source errors are separated through phase-locked acquisition and orthogonal decoupling, improving metrological correction accuracy; and a closed loop is formed through an adaptive algorithm and dual-channel verification to ensure accurate calibration and stable equipment operation.

Description

Technical Field

[0001] This invention relates to the fields of electrical variable measurement and magnetic variable measurement technology, specifically to a self-calibration method and system based on the metrological function of an intelligent measurement switch. Background Technology

[0002] With the increasing integration of nonlinear loads and distributed power sources in low-voltage distribution networks, grid operation fluctuations are becoming more frequent. Intelligent metering switches simultaneously perform both line disconnection and energy metering functions, with metering data directly used for line loss statistics and electricity consumption calculations. During long-term energized operation, the metering sampling channels are susceptible to multiple factors such as ambient temperature, electromagnetic interference, changes in contact condition, and mechanical attenuation, leading to continuous deviations in metering values. Furthermore, the wide distribution of field equipment makes routine calibration difficult, hindering the maintenance of metering accuracy required during long-term operation.

[0003] Current intelligent measurement switch calibration methods are implemented in two ways: offline and online. Offline calibration requires removing the equipment and disconnecting the power supply line, relying on external standard devices to adjust parameters. This involves many steps and can cause power outages. Online calibration relies on internally generated reference signals for comparison. However, these reference signals are prone to deviations due to operating time and environmental changes, making it impossible to maintain calibration accuracy. Furthermore, current calibration methods only correct for sampling circuit deviations, failing to independently address various influencing factors and lacking calibration result verification and anomaly handling procedures, thus failing to achieve continuous and effective measurement accuracy correction. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a self-calibration method and system based on the metrological function of an intelligent measuring switch. It uses the inherent step electrical signal of the intelligent measuring switch contact during the pre-breakdown stage as the sole calibration benchmark, constructs a full-condition standard calibration benchmark library and stores it encrypted, eliminating the need for external standard equipment and internal signal modules. This allows for in-situ self-calibration without shutting down or disassembling the equipment. Through time-locked acquisition, orthogonal feature extraction, and a multi-physics orthogonal decoupling model, various errors are independently decomposed and metrological deviations are accurately calculated. Then, a full-range segmented adaptive algorithm generates calibration coefficients, forming a complete closed loop with dual-channel verification and anomaly tolerance processing. The overall solution is simple in process and stable in operation, solving the problems of traditional calibration, such as the inability to achieve continuous and effective metrological accuracy correction, easy benchmark drift, inability to separate error coupling, and lack of closed-loop verification. This enables long-term stable and continuous effective metrological accuracy correction for intelligent measuring switches.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: On the one hand, a self-calibration method based on the metrological function of an intelligent measurement switch, the specific steps of which are as follows: Inherent benchmark construction: Under standard metrological test environment, the inherent step electrical signal of gas breakdown during the pre-breakdown stage of the contact in the opening and closing operation of the intelligent measuring switch is collected. The signal generated by the physical characteristics of the switch body is used as the only calibration benchmark. The inherent electrical characteristic parameters of the signal are extracted to construct a standard calibration benchmark library covering all working conditions. The benchmark library is stored in the read-only authorized storage area of ​​the switch through hardware encryption, and only the calibration execution program can access and read it. Timing phase-locked acquisition: The switch monitors the self-calibration trigger conditions under normal grid operation without shutdown. When the trigger conditions are met, the calibration process is started. The signal acquisition is synchronized with the phase lock of the opening and closing operation mechanism. A multi-channel synchronous sampling circuit is used to acquire real-time pre-breakdown step electrical signals. Orthogonal feature extraction: The acquired real-time step electrical signal is orthogonally decomposed to separate coupled interference components and retain inherent electrical features, and real-time feature parameters that match the dimensions of the standard calibration benchmark library are extracted. Multi-physics orthogonal decoupling: real-time characteristic parameters are compared with standard characteristic parameters of the corresponding working conditions, multi-physics operating parameters are synchronously input, and the independent contribution of each error factor is separated through a multi-factor orthogonal decoupling model to calculate the amplitude error and phase angle difference of the metering sampling channel; Adaptive closed-loop calibration: Based on the amplitude error and phase angle difference, calibration coefficients for the metering sampling channel are generated through a full-range segmented adaptive algorithm. The calibration coefficients are then sent to the metering sampling unit via a communication bus with a verification mechanism. Combined with dual-channel redundancy verification, the calibration validity is verified and anomaly tolerance is handled.

[0006] Furthermore, in the inherent benchmark construction step, the combined signal of step voltage and step current generated by the contact gap under the constraint of Pashin's law is collected as an inherent step electrical signal. The rise time, amplitude stability, phase linearity, and step duration of the step signal are extracted as inherent electrical characteristic parameters. A multi-dimensional feature matrix covering the entire temperature range, the entire rated voltage range, the entire opening and closing speed range, and the entire forward and reverse power flow conditions is constructed. The matrix is ​​encrypted using a hardware encryption engine and stored in a read-only authorized partition, which can only be accessed and read by the calibration execution program.

[0007] Furthermore, in the timing phase-locked acquisition step, the switch, under the normal non-stop operation state of the power grid, monitors the triggering conditions according to the priority of metering over-tolerance triggering, mechanical degradation triggering, environmental change triggering, operation triggering, periodic triggering, and remote authorization triggering. The acquisition is performed by a multi-channel synchronous sampling circuit with a sampling rate of not less than 1MHz, so that the sampling timing is phase-locked with the contact action phase and the sampling synchronization error is not greater than 1μs.

[0008] Furthermore, in the multi-physics orthogonal decoupling step, the operating parameters of the switch's internal temperature, vibration, electromagnetic interference, and mechanical characteristics are synchronously input. A multi-factor orthogonal decoupling model is used to calculate the total amplitude error of the metering sampling channel. The decoupling formula for the total amplitude error is as follows: in, This represents the total amplitude error of the metering sampling channel; This is due to the inherent nonlinear error of the metering sampling channel; This is for temperature drift error; Electromagnetic interference error; This is due to mechanical property degradation error; The contact resistance circuit loss error is used to eliminate the multicollinearity of various error factors through orthogonal transformation, and each error component is independently quantified and calculated.

[0009] Furthermore, in the multi-factor orthogonal decoupling model, the formula for calculating the mechanical property degradation error is: in, The measurement amplitude error is caused by the degradation of mechanical characteristics; k is the mechanical degradation error coefficient calibrated at the factory of the switch; N is the current cumulative number of opening and closing operations of the switch; This is the factory-standard number of operation cycles for the switch; This refers to the real-time opening and closing time of this circuit breaker operation. This refers to the standard opening and closing time specified by the manufacturer when the switch is manufactured.

[0010] Furthermore, in the adaptive closed-loop calibration step, the formula for calculating the amplitude calibration coefficient is: in, This is the amplitude calibration coefficient for the metering sampling channel; Standard amplitude stability value of the contact pre-breakdown step signal taken from the standard calibration reference library; The amplitude stability value of the pre-breakdown step signal is collected in real time. Based on the amplitude calibration coefficient and phase angle difference, the calibration coefficient matrix is ​​generated by fitting the rated current range in segments to generate a calibration coefficient matrix covering the entire range and corresponding to each voltage and current sampling channel of the three phases. The calibration coefficient is then sent down via a communication bus with CRC verification mechanism.

[0011] Furthermore, in the adaptive closed-loop calibration step, after the calibration coefficients are issued, the three-phase electrical parameter data for the next complete power frequency grid cycle are collected, and the calibration error is calculated. When the calibration error meets the legal metrological accuracy requirements, the calibration coefficients are locked and the calibration data is encrypted and stored. When the calibration error exceeds the legal metrological accuracy requirements, the previous version of valid calibration coefficients is restored and the recalibration process is triggered. When a power grid fault or hardware abnormality is detected during the calibration process, fault tolerance processing is performed, the calibration process is paused and switched to the protection operation mode, and the previous version of valid calibration coefficients is restored.

[0012] Furthermore, in the orthogonal feature purification step, the real-time step electrical signal is separated into pre-breakdown inherent feature components and coupled interference components through orthogonal decomposition processing, fully preserving the original physical characteristics of the pre-breakdown signal, and extracting real-time feature parameters that are completely matched with the dimensions of the standard calibration reference library, with a feature extraction error of no more than 0.02%.

[0013] On the other hand, a self-calibration system based on the intelligent measurement switch function includes: Inherent reference construction module: used to collect inherent step electrical signals of contact pre-breakdown, extract inherent electrical characteristic parameters, build and hardware-encrypt and store the full-condition standard calibration reference library. The storage area is a read-only authorized area, which can only be accessed and read by the calibration execution program. The timing phase-locked acquisition module is used to monitor the self-calibration trigger conditions according to priority under the normal power grid operation without shutdown, and synchronize with the phase lock phase of the opening and closing mechanism. It uses a high sampling rate multi-channel circuit to acquire real-time pre-breakdown step electrical signals. Orthogonal feature purification module: used to perform orthogonal decomposition processing on real-time step electrical signals, separate coupled interference components, and extract real-time feature parameters that perfectly match the dimensions of the benchmark library; Multiphysics orthogonal decoupling module: used to compare real-time features with standard feature parameters, input multiphysics operating parameters, separate error components through multi-factor orthogonal decoupling model, and calculate amplitude error and phase angle difference; Adaptive closed-loop calibration module: used to generate calibration coefficients through full-range segmented adaptive algorithm, distribute coefficients via verification communication bus, and perform main and auxiliary dual-channel redundancy verification, calibration validity verification and fault tolerance handling; All modules are integrated inside the switch body and electrically isolated from each other, working together to complete the entire self-calibration process.

[0014] Compared with existing technologies, this self-calibration method and system based on intelligent measurement switch measurement function has the following advantages: I. This invention generates calibration coefficients through a full-range segmented adaptive algorithm, transmits parameters via a communication bus with a verification mechanism, and employs dual-channel redundant verification to confirm results and handle anomalies. This method forms a complete calibration execution process, ensuring accurate transmission and writing of calibration parameters. It allows for timely switching and handling in case of calibration deviations or equipment malfunctions, enabling continuous correction of metrological parameters and maintaining the equipment's metrological accuracy to meet usage requirements.

[0015] II. This invention synchronizes signal acquisition with the phase-locked operation of the opening and closing mechanism, performs orthogonal decomposition processing on the acquired signal and extracts corresponding dimensional feature parameters, synchronously integrates multi-physics operating parameters, and employs a multi-factor orthogonal decoupling model to distinguish various error sources and calculate the measurement amplitude and phase deviation. This method can calculate and correct measurement deviations caused by different influencing factors separately, solving the problems of mixed and superimposed errors and insufficient correction accuracy in existing calibration methods, and achieving accurate differentiation and calculation of measurement deviations.

[0016] Third, this invention uses the inherent step electrical signal during the pre-breakdown stage of the contact as a calibration benchmark to construct a full-condition standard calibration benchmark library, which is stored in a read-only authorized area using hardware encryption. Only the calibration program can read and access this library. This method eliminates the need for external standard devices and internal signal generation structures, and can complete the calibration process while the equipment is energized, without the need for disassembly or power-off operations. This solves the problems of existing calibration methods, such as easy benchmark deviation, reliance on external equipment, and impact on power supply.

[0017] Other advantages, objectives and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination or study, or may be learned from the practice of the invention. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0019] Figure 1 This is an overall flowchart of the self-calibration method based on the intelligent measurement switch function of the present invention; Figure 2 This is a flowchart of the timing phase-locked acquisition trigger condition judgment and synchronous sampling process of the present invention; Figure 3 This is a flowchart of the adaptive closed-loop calibration and anomaly tolerance processing of the present invention. Detailed Implementation

[0020] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0021] This embodiment discloses a self-calibration method and system based on the metrological function of an intelligent measurement switch, applied in the fields of electrical and magnetic variable measurement technology. This embodiment uses the inherent step electrical signal of contact pre-breakdown as the sole calibration benchmark, constructs a full-condition encrypted standard calibration benchmark library, and sequentially performs time-locked synchronous acquisition, orthogonal feature purification, multi-physics field orthogonal decoupling, and adaptive closed-loop calibration. The entire process integrates three sets of quantitative mathematical formulas to complete error decoupling and coefficient generation. The system adopts a modular integrated architecture and is electrically isolated, eliminating the need for disassembly, power outages, and external standard equipment. It can independently isolate multi-factor coupled metrological errors, achieving uninterrupted online calibration of the metrological sampling channel and stably maintaining the equipment's metrological accuracy.

[0022] The overall flowchart of the method of this invention is as follows: Figure 1 As shown, the specific implementation process is as follows: Inherent benchmark construction: The inherent benchmark construction phase is the foundation of the self-calibration process, used to generate the standard benchmark data required for calibration. The operating environment for this phase must meet the standard test conditions corresponding to the statutory metrological verification procedures. Before the intelligent measuring switch is put into operation, the control switch performs multiple opening and closing operations, and the switch body unit outputs an inherent step electrical signal during the contact pre-breakdown stage. This signal is formed by gas breakdown of the contact gap under the constraint of Pashin's law, and includes a step voltage signal and a step current signal. It is an inherent physical characteristic signal of the switch body and does not require input from an external signal generation module.

[0023] After acquiring this set of signals, the inherent benchmark construction module extracts four core inherent electrical characteristic parameters: rise time of the step signal, amplitude stability, phase linearity, and step duration. Multiple rounds of calibration tests are conducted across the entire temperature range, rated voltage range, opening and closing speed range, and forward and reverse power flow conditions. The calibration data from all operating conditions are integrated to form a multi-dimensional standard calibration benchmark library. To ensure data security, the benchmark library is encrypted using a hardware encryption engine and stored in a read-only authorized partition of the encrypted storage unit. This storage area has strict access permissions; only the calibration execution program has read access. The benchmark data remains unwriteable and tamper-proof throughout the entire process, providing a unified and stable reference standard for subsequent error comparisons.

[0024] Timing-locked acquisition: The timing-locked loop (PLL) acquisition phase is executed under normal power grid operation, requiring no power interruption or equipment disassembly. The PLL acquisition module cyclically monitors self-calibration trigger conditions according to preset priorities. These trigger conditions are, in order: metering error trigger, mechanical degradation trigger, sudden environmental change trigger, operational trigger, periodic trigger, and remote authorization trigger. For example... Figure 2 As shown, when any one of the triggering conditions is detected and an action command or actual action is detected from the opening and closing operating mechanism, the self-calibration process is immediately initiated.

[0025] The acquisition module establishes a strict phase linkage with the opening and closing operating mechanism to achieve phase-locked synchronization between signal acquisition timing and contact action phase. This is to eliminate acquisition deviations caused by action delay and grid phase offset. The acquisition operation employs a multi-channel synchronous sampling circuit with a sampling rate of no less than 1MHz and a sampling synchronization error of no more than 1μs. Through a high-precision sampling mechanism, the real-time step electrical signal during the contact pre-breakdown stage of this opening and closing operation is accurately acquired. After the raw signal is acquired, it is directly transmitted to the orthogonal feature purification module for subsequent processing to ensure the timeliness and accuracy of data transmission.

[0026] Orthogonal feature purification: The orthogonal feature extraction stage is used to remove signal interference and retain effective electrical features, directly determining the accuracy of subsequent error calculations. After receiving the real-time step electrical signal, the orthogonal feature extraction module uses an orthogonal decomposition algorithm to deeply split the mixed signal. Specifically, the mixed signal is projected onto the orthogonal feature space, separating it into two types of data: pre-breakdown intrinsic feature components and coupled interference components. The coupled interference components include invalid signals from power grid harmonics, electromagnetic interference, and mechanical vibration. The extraction process directly removes the interference components, completely preserving the original physical characteristics of the step signal and avoiding the loss of feature information.

[0027] After purification, the module extracts real-time feature parameters that perfectly match the dimensions of the standard calibration benchmark library. To ensure data validity, the feature extraction error is strictly controlled to ensure it is no greater than 0.02%. Once the parameter matching degree meets the requirements for subsequent error calculation, the processed feature parameters are transmitted to the multiphysics orthogonal decoupling module to provide clean feature data for error calculation.

[0028] Multiphysics orthogonal decoupling: The multi-physics orthogonal decoupling stage is the core calculation stage for measurement errors. This embodiment fully applies two sets of error calculation formulas and synchronously accesses multi-physics data to complete accurate decoupling. After receiving real-time characteristic parameters, the multi-physics orthogonal decoupling module first retrieves the standard characteristic parameters corresponding to the operating condition from the standard calibration reference library to complete numerical comparison. At the same time, the module accesses real-time operating parameters collected by the multi-physics sensing unit. These parameters include the switch's internal temperature, vibration intensity, electromagnetic interference intensity, opening and closing time, cumulative number of actions, and contact resistance.

[0029] The module invokes a built-in multi-factor orthogonal decoupling model to perform calculations, first calculating the total amplitude error of the metering sampling channels. The total amplitude error is calculated using a superposition formula, expressed as: in, This represents the total amplitude error of the metering sampling channel; This is due to the inherent nonlinear error of the metering sampling channel; This is for temperature drift error; Electromagnetic interference error; This is due to mechanical property degradation error; The error is related to the contact resistance circuit loss. During the calculation, the model employs orthogonal transformation to eliminate multicollinearity among various error factors, thereby independently separating the contribution of each type of error factor to the total error and completing quantification calculation. For the critical component of mechanical characteristic degradation error, a dedicated correction formula is used for precise calculation, expressed as: in, The measurement amplitude error is caused by the degradation of mechanical characteristics; k is the mechanical degradation error coefficient calibrated at the factory of the switch; N is the current cumulative number of opening and closing operations of the switch; This is the factory-standard number of operation cycles for the switch; This refers to the real-time opening and closing time of this circuit breaker operation. This refers to the standard opening and closing time specified by the manufacturer when the switch is manufactured. By combining the above formulas, the combined effects of mechanical performance degradation and multi-physical field environment on measurement accuracy are accurately quantified. After the decoupling operation is completed, the amplitude error and phase angle difference of the measurement sampling channel are output and transmitted to the adaptive closed-loop calibration module.

[0030] Adaptive closed-loop calibration: The adaptive closed-loop calibration phase fully applies the amplitude calibration coefficient calculation formula, executing the entire process of parameter generation, distribution, verification, and fault tolerance to form a complete calibration closed loop. After receiving the amplitude error and phase angle difference, the adaptive closed-loop calibration module calculates the amplitude calibration coefficient using a ratio formula, expressed as: in, This is the amplitude calibration coefficient for the metering sampling channel; Standard amplitude stability value of the contact pre-breakdown step signal taken from the standard calibration reference library; The calibration coefficient matrix is ​​generated by combining the amplitude calibration coefficient and phase angle difference with the real-time acquisition of the pre-breakdown step signal amplitude stability value, and performing segmented fitting according to the rated current range to generate a calibration coefficient matrix covering the entire range and adapting to each voltage and current sampling channel of the three phases. After the calibration coefficient matrix is ​​generated, it is transmitted through a communication bus with CRC check mechanism. Before transmission, the main control unit calculates the CRC check code of the data block; after receiving the data, the receiving end metering sampling unit recalculates the CRC check code and compares it with the transmitting end. After the data verification is successful, the calibration coefficients are sent to the metering sampling unit to complete the online update of the metering parameters.

[0031] like Figure 3 As shown, after the parameters are updated, a dual-channel redundancy check is immediately performed. The module collects three-phase electrical parameter data for a complete power frequency cycle and calculates the calibrated measurement error. If the error meets the legal metrological accuracy standard, the calibration coefficients are locked and the entire calibration process data is encrypted and stored in the historical data partition. If the error exceeds the accuracy standard, the previous valid calibration coefficients are immediately restored and the calibration process is restarted.

[0032] Throughout the calibration process, the system monitors the power grid and hardware status in real time. When a power grid fault, load change, sampling channel failure, or communication anomaly is detected, the calibration process is immediately paused and switched to protection operation mode. At the same time, the previous valid calibration coefficients are restored to ensure that the basic disconnection protection function of the switch is not affected and to maintain the safe operation of the equipment.

[0033] System collaborative operation: The modules of the self-calibration system work in concert to operate the aforementioned method throughout the entire process, forming a complete technical solution. The switch body unit acts as the signal source, providing an inherent step reference signal; the metrology sampling unit completes high-synchronous-precision signal acquisition and metrology parameter updates; the multi-physics sensing unit acts as the data input source, providing environmental and mechanical state parameters; the main control unit acts as the core control center, coordinating the entire process of logic control and algorithm calculation, performing orthogonal decomposition, decoupled model calculation, and coefficient generation; the encrypted storage unit is responsible for the secure storage of the reference library and calibration data; the communication unit realizes remote command interaction and data upload; and the power supply unit provides stable power supply under all operating conditions, with backup power supporting calibration operations in the open state. All modules of the entire system work together without interference, ensuring the complete implementation of the self-calibration method.

[0034] This embodiment replaces the traditional external reference source with the inherent step signal of the switch itself, fundamentally avoiding the problems of reference drift and dependence on external devices. Through a complete process design including time-locked phase-locked synchronous acquisition, orthogonal feature purification, multi-physics field orthogonal decoupling, and adaptive closed-loop calibration, it can accurately separate multi-factor coupled measurement errors and achieve full-range online accurate calibration. This embodiment does not require power outages or disassembly, the calibration process is closed-loop and controllable, and the accuracy standard of the measurement sampling channel can be maintained for a long time. It effectively solves the technical problems of insufficient accuracy, cumbersome process, and poor adaptability to operating conditions of existing calibration methods, and meets the actual needs of large-scale operation and maintenance of intelligent measurement switches in low-voltage distribution networks.

[0035] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A self-calibration method based on the measurement function of an intelligent measurement switch, characterized in that, The specific steps of this method are as follows: Inherent benchmark construction: Under standard metrological test environment, the inherent step electrical signal of gas breakdown during the pre-breakdown stage of the contact in the opening and closing operation of the intelligent measuring switch is collected. The signal generated by the physical characteristics of the switch body is used as the only calibration benchmark. The inherent electrical characteristic parameters of the signal are extracted to construct a standard calibration benchmark library covering all working conditions. The benchmark library is stored in the read-only authorized storage area of ​​the switch through hardware encryption, and only the calibration execution program can access and read it. Timing phase-locked acquisition: The switch monitors the self-calibration trigger conditions under normal grid operation without shutdown. When the trigger conditions are met, the calibration process is started. The signal acquisition is synchronized with the phase lock of the opening and closing operation mechanism. A multi-channel synchronous sampling circuit is used to acquire real-time pre-breakdown step electrical signals. Orthogonal feature extraction: The acquired real-time step electrical signal is orthogonally decomposed to separate coupled interference components and retain inherent electrical features, and real-time feature parameters that match the dimensions of the standard calibration benchmark library are extracted. Multi-physics orthogonal decoupling: real-time characteristic parameters are compared with standard characteristic parameters of the corresponding working conditions, multi-physics operating parameters are synchronously input, and the independent contribution of each error factor is separated through a multi-factor orthogonal decoupling model to calculate the amplitude error and phase angle difference of the metering sampling channel; Adaptive closed-loop calibration: Based on the amplitude error and phase angle difference, calibration coefficients for the metering sampling channel are generated through a full-range segmented adaptive algorithm. The calibration coefficients are then sent to the metering sampling unit via a communication bus with a verification mechanism. Combined with dual-channel redundancy verification, the calibration validity is verified and anomaly tolerance is handled.

2. The self-calibration method based on intelligent measurement switch function according to claim 1, characterized in that, In the inherent benchmark construction step, the combined signal of step voltage and step current generated by the contact gap under the constraint of Pashin's law is collected as the inherent step electrical signal. The rise time, amplitude stability, phase linearity, and step duration of the step signal are extracted as inherent electrical characteristic parameters. A multi-dimensional feature matrix covering the entire temperature range, the entire rated voltage range, the entire opening and closing speed range, and the entire forward and reverse power flow conditions is constructed. The matrix is ​​encrypted using a hardware encryption engine and stored in a read-only authorized partition. Only the calibration execution program can access and read this benchmark library.

3. The self-calibration method based on the intelligent measurement switch function according to claim 1, characterized in that, In the timing phase-locked acquisition step, the switch is in normal, uninterrupted operation of the power grid. The triggering conditions are monitored according to the priority of metering over-tolerance triggering, mechanical degradation triggering, environmental change triggering, operation triggering, periodic triggering, and remote authorization triggering. The acquisition is performed by a multi-channel synchronous sampling circuit with a sampling rate of not less than 1MHz, so that the sampling timing is phase-locked with the contact action phase and the sampling synchronization error is not greater than 1μs.

4. The self-calibration method based on intelligent measurement switch function according to claim 1, characterized in that, In the multi-physics orthogonal decoupling step, the operating parameters of the switch's internal temperature, vibration, electromagnetic interference, and mechanical characteristics are synchronously input. A multi-factor orthogonal decoupling model is used to calculate the total amplitude error of the metering sampling channel. The decoupling formula for the total amplitude error is as follows: in, This represents the total amplitude error of the metering sampling channel; This is due to the inherent nonlinear error of the metering sampling channel; This is for temperature drift error; Electromagnetic interference error; This is due to mechanical property degradation error; The contact resistance circuit loss error is used to eliminate the multicollinearity of various error factors through orthogonal transformation, and each error component is independently quantified and calculated.

5. The self-calibration method based on the intelligent measurement switch function according to claim 4, characterized in that, In the multi-factor orthogonal decoupling model, the formula for calculating the mechanical property degradation error is: in, The measurement amplitude error is caused by the degradation of mechanical characteristics; k is the mechanical degradation error coefficient calibrated at the factory of the switch; N is the current cumulative number of opening and closing operations of the switch; This is the factory-standard number of operation cycles for the switch; This refers to the real-time opening and closing time of this circuit breaker operation. This refers to the standard opening and closing time specified by the manufacturer when the switch is manufactured.

6. The self-calibration method based on the intelligent measurement switch function according to claim 1, characterized in that, In the adaptive closed-loop calibration step, the formula for calculating the amplitude calibration coefficient is: in, This is the amplitude calibration coefficient for the metering sampling channel; Standard amplitude stability value of the contact pre-breakdown step signal taken from the standard calibration reference library; The amplitude stability value of the pre-breakdown step signal is collected in real time. Based on the amplitude calibration coefficient and phase angle difference, the calibration coefficient matrix is ​​generated by fitting the rated current range in segments to generate a calibration coefficient matrix covering the entire range and corresponding to each voltage and current sampling channel of the three phases. The calibration coefficient is then sent down via a communication bus with CRC verification mechanism.

7. The self-calibration method based on intelligent measurement switch function according to claim 1, characterized in that, In the adaptive closed-loop calibration step, after the calibration coefficients are issued, the three-phase electrical parameter data of the next complete power frequency grid cycle are collected, and the calibration error is calculated. When the calibration error meets the statutory metrological accuracy requirements, the calibration coefficients are locked and the calibration data is encrypted and stored. When the calibration error exceeds the statutory metrological accuracy requirements, the previous version of valid calibration coefficients is restored and the recalibration process is triggered. When a power grid fault or hardware abnormality is detected during the calibration process, fault tolerance processing is performed, the calibration process is paused and switched to the protection operation mode, and the previous version of valid calibration coefficients is restored.

8. The self-calibration method based on intelligent measurement switch function according to claim 1, characterized in that, In the orthogonal feature purification step, the real-time step electrical signal is separated into pre-breakdown inherent feature components and coupled interference components through orthogonal decomposition processing, preserving the original physical characteristics of the pre-breakdown signal completely, and extracting real-time feature parameters that are completely matched with the dimensions of the standard calibration reference library, with a feature extraction error of no more than 0.02%.

9. A self-calibration system based on intelligent measurement switch function, the system being applicable to the self-calibration method based on intelligent measurement switch function as described in any one of claims 1-8, characterized in that, The system includes: Inherent reference construction module: used to collect inherent step electrical signals of contact pre-breakdown, extract inherent electrical characteristic parameters, build and hardware-encrypt and store the full-condition standard calibration reference library. The storage area is a read-only authorized area, which can only be accessed and read by the calibration execution program. The timing phase-locked acquisition module is used to monitor the self-calibration trigger conditions according to priority under the normal power grid operation without shutdown, and synchronize with the phase lock phase of the opening and closing mechanism. It uses a high sampling rate multi-channel circuit to acquire real-time pre-breakdown step electrical signals. Orthogonal feature purification module: used to perform orthogonal decomposition processing on real-time step electrical signals, separate coupled interference components, and extract real-time feature parameters that perfectly match the dimensions of the benchmark library; Multiphysics orthogonal decoupling module: used to compare real-time features with standard feature parameters, input multiphysics operating parameters, separate error components through multi-factor orthogonal decoupling model, and calculate amplitude error and phase angle difference; Adaptive closed-loop calibration module: used to generate calibration coefficients through full-range segmented adaptive algorithm, distribute coefficients via verification communication bus, and perform main and auxiliary dual-channel redundancy verification, calibration validity verification and fault tolerance handling; All modules are integrated inside the switch body and electrically isolated from each other, working together to complete the entire self-calibration process.

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