Electric energy error test system based on smart metering switch

Abstract

The application discloses an electric energy error test system based on an intelligent measurement switch and relates to the technical field of electric energy test.The system comprises an intelligent measurement switch and an upper computer.The intelligent measurement switch comprises a sampling module, a processing module, a signal shunting and calibration module and a communication module.The upper computer is a data processing center and comprises a data receiving module, a decryption and analysis module and a display and storage module.The electric energy error test system based on the intelligent measurement switch comprises a multilayer nested signal shunting and calibration module, which can automatically switch a shunting path and calibration parameters according to different current and voltage levels, effectively overcomes the limitations of the fixed circuit structure of traditional equipment, enables a low-range shunting path and adaptive calibration parameters at low current and voltage, accurately captures weak electric energy signal changes and reduces measurement errors, and switches to a large current shunting path and corresponding calibration parameters for high current and voltage scenes to stably cope with large signal impacts.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electric energy testing, in particular to an electric energy error testing system based on an intelligent measurement switch. BACKGROUND

[0002] In modern power systems, electric energy as the main form of energy, its accurate measurement and error testing play a crucial role in the reliability, economy and fairness of power supply, accurate electric energy error testing can ensure the accuracy of electric energy metering, avoid disputes between power companies and users caused by measurement error, and also help the optimal operation and fault diagnosis of power systems.

[0003] However, the existing electric energy error testing technology lacks self-adaptive ability to different current and voltage levels when facing the increasingly complex power environment, and lacks effective encryption and tamper-proof mechanism considering the particularity of electric energy error testing data, which makes the electric energy error testing data face the risk of being stolen and tampered during transmission, seriously affecting the authenticity and reliability of the data, and further leading to misjudgment of the accuracy of electric energy metering, affecting the normal operation and management decision of the power system.

[0004] In summary, the existing electric energy error testing technology cannot meet the strict requirements of modern power systems for electric energy metering accuracy and data security. Therefore, there is an urgent need for an innovative electric energy error testing system based on an intelligent measurement switch, which can adapt to different current and voltage conditions while ensuring the safety and reliability of data transmission. SUMMARY

[0005] The purpose of the present application is to overcome the shortcomings of the prior art and provide an electric energy error testing system based on an intelligent measurement switch. The system uses a multi-layer nested signal shunt and calibration module, which can automatically switch the shunt path and calibration parameters under different current and voltage levels. The module and the data processing interact through an encrypted transmission function communication protocol, ensuring the accuracy and security of electric energy error testing data during transmission.

[0006] To solve the above technical problems, the present application provides the following technical solution: an electric energy error testing system based on an intelligent measurement switch, which comprises an intelligent measurement switch and an upper computer. The intelligent measurement switch comprises a sampling module, a processing module, a signal shunt and calibration module, and a communication module. The upper computer is a data processing center, comprising a data receiving module, a decryption and analysis module, and a display and storage module.

[0007] The sampling module is used for collecting electric energy data D, the electric energy data D including current signal I(t) and voltage signal U(t), the current signal I(t) representing current instantaneous value changing with time t, and the voltage signal U(t) representing voltage instantaneous value changing with time t;

[0008] The processing module judges current current-voltage level according to the collected signal, analyzes the signal fed back by the signal shunting and calibration module, and transmits data to the upper computer through the communication module;

[0009] The signal shunting and calibration module can automatically switch shunting path and calibration parameters according to different current-voltage level judgment results, and feed the adjusted signal back to the processing module, the shunting path switching being in the form of S(U(t), I(t)), when U(t)×I(t)<P1, S(U(t), I(t))=1, the first shunting path and the first calibration parameter set {C 11 , C 12 , …, C 1n} being enabled, when P1≤U(t)×I(t)<P2, S(U(t), I(t))=2, the second shunting path and the second calibration parameter set {C 21 , C 22 , …, C 2m} being enabled, wherein P1 and P2 are power threshold values, and n and m are the number of calibration parameters;

[0010] The communication module uses wireless communication technology to transmit data with the processing module and the upper computer, and uses a communication protocol to protect the safety of data in the transmission process, the communication protocol being a communication encryption rule established between the smart metering switch and the upper computer for the safety of data transmission, the encryption function of the encryption rule being E(D, k), wherein k is an encryption key, and the transmitted electric energy data D is sent to the upper computer after being encrypted by the encryption function E(D, k);

[0011] The data receiving module is used for receiving encrypted data transmitted by the smart metering switch;

[0012] The decryption and analysis module is used for decrypting the encrypted data and deeply analyzing and processing electric energy error, and when decrypting the data, a decryption function D=D(E(d, k), k -1 ) corresponding to the encryption function E(D, k) is used for decryption, wherein k -1 is a decryption key corresponding to the encryption key k, and the electric energy error is the deviation between actual electric energy measurement value and real electric energy value, and the real electric energy value is evaluated by comprehensively considering active power, reactive power and apparent power;

[0013] The display and storage module visualizes the analysis result and stores data for query and statistics.

[0014] Further, the sampling module includes a voltage sampling circuit and a current sampling circuit, the voltage sampling circuit adopts a resistance voltage division sampling structure, for voltage division resistors R1 and R2, a voltage signal sampled is wherein U0(t) is an original voltage input signal;

[0015] The current sampling circuit adopts a Hall sensor, and the sensitivity of the Hall sensor is set as K H , the magnetic field strength is B(t), the current passing through the Hall sensor is I(t), and a voltage signal V H (t) sampled is K H B(t)I(t), the current sampling value I(t) is obtained by conversion of V H (t), and the conversion relationship is

[0016] Further, the processing module determines the current voltage level by calculating the instantaneous power P(t) = U(t) x I(t), setting the power level division interval as [0, P1), [P1, P2), …, [Pi, Pi+1), where i = 1, 2, …, and when P(t) falls into the interval [0, P1), it is determined as a low power level, corresponding to the first shunt path and the first calibration parameter set;

[0017] When P(t) falls into the interval [P1, P2), it is determined as a medium power level, corresponding to the second shunt path and the second calibration parameter set, and so on. The boundary value P i of the power level division interval is determined based on statistical analysis of actual power data, that is, the number of statistical samples is N, the power of the jth sample is P j , and after sorting P j , P i is determined according to the sample number distribution of different power segments, so that the sample numbers in each power level interval are relatively balanced, that is, wherein n i is the sample number in the ith power level interval, and δ is a sample number difference threshold.

[0018] Further, the first shunt path of the signal shunt and calibration module includes a precision resistor R s1 and an adjustable capacitor C s1 in series, and C 11 , C 12 , …, C 1n in the first calibration parameter set {C 11 , C s1 , …, C s1}.For precision resistor R s1 The temperature compensation coefficient is calculated, and the resistance value R before compensation is also used, based on the ambient temperature T. s1 (0), then the compensated resistance value R s1 (T)=R s1 (0)(1+C 11 T), C 12 For adjustable capacitor C s1 The frequency response correction coefficient is calculated using the input signal frequency f and the capacitive reactance when uncorrected. Modified capacitive reactance

[0019] The second shunt path includes a shunt resistor R connected in parallel. p2 and inductor L p2 The second calibration parameter set {C 21 C 22 C 2m C in} 21 For shunt resistor R p2 The nonlinear correction coefficient, the current through the shunt resistor is I p2 The voltage across the terminals is U p2 The resistance value before correction is R. p2 (0), the corrected resistance value C 22 For inductor L p2 The magnetic saturation correction coefficient is obtained by using the magnetic field strength B. L (t), inductance value L before correction p2 (0), the corrected inductance value L p2 (B L (t))=L p2 (0)(1–C 22 B L (t) 2 ).

[0020] Furthermore, the communication module employs wireless communication technology, and the transmission power P of the wireless communication technology is set. t Receiver sensitivity S r Communication frequency f c Its communication distance d is related to the transmission power P t Receiver sensitivity S r and communication frequency f c The relationship is Where λ is the signal wavelength and α is the propagation loss coefficient, which is adjusted by the transmission power P. t and communication frequency f c Adaptable to different communication distance requirements.

[0021] Further, the encryption function E(D, k) of the communication protocol in the communication module adopts a hybrid encryption mode, which includes symmetric encryption and asymmetric encryption, wherein the symmetric encryption is obtained by symmetrically encrypting the data D to obtain E s (D, k s ), k s is a symmetric encryption key, which is generated by the smart metering switch based on a pseudo-random number generator, and is generated as k s =PRNG(S1, S2, …, S m ), wherein S i is a seed value, including the device number ID of the smart metering switch, the current timestamp T s and the sampling period T c , i.e. S1=ID, S2=T s , S3=T c , the asymmetric encryption is performed on the symmetric encryption key k s , and the asymmetric encryption is E a (k s , k p ), wherein k p is a public key, which is generated by the upper computer and transmitted to the smart metering switch, and the encrypted data E(D, k)=E a (E s (D, k s ), k p ).

[0022] Further, the decryption and analysis module of the upper computer calculates the active power of the electric energy after decrypting the data wherein T is an integral time period, I(t) represents the current instantaneous value of the current signal changing with time t, U(t) represents the voltage instantaneous value of the voltage signal changing with time t, the reactive power is the apparent power , and the electric energy error wherein P m is the power value measured by the electric energy meter, and by comparing with the electric energy error standard value ΔE0, it is determined whether the electric energy error range is within the normal range, wherein the electric energy error standard value ΔE0 is determined according to the statistical analysis of the electric energy data, i.e. the statistical electric energy error sample is ΔE j , j=1, 2, …, J, after sorting ΔE j , the middle value in the confidence interval is taken as ΔE0.

[0023] Further, the processing module of the smart metering switch performs self-diagnosis during operation, and the self-diagnosis period is T d , and the self-diagnosis is performed every T dThe time is functionally detected to the sampling module, the signal shunt and calibration module and the communication module, for the sampling module, the standard voltage signal U s (t) and the standard current signal I s (t) are injected, whether the sampling value is within the error range is checked, and the sampling error threshold is set as epsilon s When And , wherein U' s (t), I' s (t) are the actual sampling values of the sampling module, then it is determined that the sampling unit is faulty;

[0024] For the signal shunt and calibration module, whether the shunt path switching function S(U(t), I(t)) is correctly switched and whether the calibration parameters are correctly applied are checked, and whether the communication is normal is judged by comparing the actual switching result and the data difference before and after calibration;

[0025] For the communication module, whether the communication is normal is judged by sending test data and checking whether the received data is complete, and when a fault is detected, a fault report is generated and the fault alarm information is sent to the upper computer.

[0026] Compared with the prior art, the electric energy error test system based on the intelligent measurement switch has the following beneficial effects:

[0027] 1. The multi-layer nested signal shunt and calibration module in the electric energy error test system based on the intelligent measurement switch can automatically switch the shunt path and the calibration parameter according to different current and voltage levels, effectively overcome the limitations of the fixed circuit structure of the traditional device, enable the low-range shunt path and the adaptive calibration parameter at low current and voltage, accurately capture the weak electric energy signal change, reduce the measurement error, switch to the large current shunt path and the corresponding calibration parameter for the high current and voltage scene, stably cope with the large signal impact, ensure the measurement accuracy is not damaged, widen the adaptability of the system to different power working conditions, significantly improve the accuracy and reliability of the electric energy error test, help the power enterprise improve the operation management level, and ensure the efficient and stable power supply.

[0028] 2. The communication protocol with high-speed encrypted transmission function between the intelligent measurement switch and the upper computer is used in the present application, the communication protocol uses an encryption algorithm to encrypt the electric energy error test data, makes the data highly safe in the transmission process, effectively resists external interference and data tampering attempts, and ensures the integrity and authenticity of the electric energy error data from the intelligent measurement switch to the upper computer.

[0029] Other advantages, objects, and features of the present application will be apparent to those skilled in the art from the following specification, and in some respects, will be learned from the study of the following text, or can be taught from the practice of the present application. Attached Figure Description

[0030] 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.

[0031] Figure 1 The flowchart shows a power error testing system based on an intelligent measurement switch.

[0032] Figure 2 This is a schematic diagram of the planar composition of an energy error testing system based on an intelligent measuring switch. Detailed Implementation

[0033] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0034] Example 1

[0035] This embodiment focuses on the specific application of a power error testing system based on an intelligent measurement switch under low current and voltage conditions. Through the coordinated operation of various functional modules in the intelligent measurement switch, including the sampling module accurately collecting power data, the processing module accurately determining the current and voltage levels and coordinating with the signal splitting and calibration module to switch to the appropriate low-range parameter path, and the communication module using an encrypted protocol to securely transmit data, the host computer receives and processes the data and accurately calculates the power error. This effectively improves the accuracy and reliability of power error testing in low-power environments, providing an efficient power monitoring and management solution for low-power scenarios such as small commercial office areas.

[0036] In practical implementation, firstly, in the power monitoring scenario of a small commercial office area, a power error testing system based on intelligent measuring switches is deployed. The intelligent measuring switches are installed in the distribution box of this area to ensure comprehensive and accurate collection of power data from all electrical equipment in the area. The host computer is located in the power management monitoring room, achieving seamless communication with the intelligent measuring switches through a stable and reliable network connection, thus constructing a complete power monitoring architecture. The intelligent measuring switch includes a sampling module, a processing module, a signal splitting and calibration module, and a communication module. The host computer is the data processing center, including a data receiving module, a decryption and analysis module, and a display and storage module. The sampling module, as the front-end data acquisition unit of the system, accurately acquires power data. It is composed of a voltage sampling circuit and a current sampling circuit. The voltage sampling circuit cleverly uses a resistor voltage divider architecture, precisely setting the values ​​of the voltage divider resistors R1 and R2 according to the formula... The voltage signal U(t) is accurately separated from the original voltage input signal U0(t). During this process, external interference and noise are effectively suppressed, ensuring the stability and accuracy of the acquired voltage signal. The current sampling circuit utilizes the Hall effect principle of the Hall sensor. When current I(t) flows through the sensor, under a magnetic field strength B(t), a voltage signal V is generated at the sensor terminals that is linearly related to both the current and the magnetic field strength. H (t)=K H B(t)I(t), with the aid of signal conditioning circuitry and high-resolution analog-to-digital converter, according to the formula V H The current is accurately converted into a digital signal I(t) representing the instantaneous value of the current. Throughout the sampling process, the continuous self-calibration and environmental compensation mechanism operates in real time, dynamically correcting the measurement deviation caused by temperature and magnetic field drift, ensuring high accuracy and high stability of current sampling, and transmitting the data to the processing module to lay a solid data foundation for subsequent power error testing.

[0037] After receiving the voltage signal U(t) and current signal I(t) from the sampling module, the processing module quickly starts the instantaneous power calculation program. It accurately calculates the instantaneous power value using the formula P(t) = U(t) × I(t). Simultaneously, its built-in precise power level discrimination logic operates closely according to the power level division interval. This interval division is based on in-depth statistical analysis of actual electrical energy data. When the calculated P(t) falls into the low power level interval [0, P1), the processing module issues an instruction to the signal splitting and calibration module to switch to the first splitting path and the first calibration parameter set. This ensures the system achieves optimal configuration for low current and voltage conditions, guaranteeing the timeliness and accuracy of the system response, and adapting to the detailed processing needs of electrical energy data in low-power scenarios. Upon receiving the instruction from the processing module, the signal splitting and calibration module activates the first splitting path and the corresponding calibration parameter set. In the first splitting path, a precision resistor R is connected in series... s1 With adjustable capacitor C s1 The core architecture consists of precision resistors R. s1 With its precise temperature compensation coefficient C 11 According to formula R s1 (T)=R s1 (0)(1+C 11 The system dynamically compensates for resistance values ​​under different ambient temperatures (T), effectively eliminating resistance fluctuations caused by temperature changes and ensuring high stability and accuracy of current signal shunting. The adjustable capacitor C... s1 With frequency response correction coefficient C 12 According to the formula By precisely adjusting the capacitive reactance characteristics for electrical signals of different frequencies, the frequency response deviation during signal transmission is effectively corrected, improving signal quality and measurement accuracy. The electrical signals, after this fine shunting and calibration process, are accurately fed back to the processing module, providing a high-fidelity signal source for subsequent analysis, processing, and data transmission, ensuring the accuracy and stability of electrical signal processing under low current and voltage conditions.

[0038] The processing module transmits the power data, processed by the signal splitting and calibration module, to the communication module. The communication module relies on wireless communication technology to build a robust communication link. To ensure the security and integrity of data transmission, a communication encryption protocol is implemented. The core encryption function E(D,k) of this protocol employs a hybrid encryption strategy, combining symmetric and asymmetric encryption. In the symmetric encryption stage, the pseudo-random number generator built into the intelligent measurement switch uses the device ID and the current timestamp T. s and sampling period T c Seed value, based on k s =PRNG(S1,S2,…,S) m (where S1 = ID, S2 = T) s S3 = Tc ) generating symmetric encryption key k s , efficiently encrypting electric energy data D to generate ciphertext E s (D, k s ); asymmetric encryption process, using the pre-allocated public key k of the upper computer p , encrypting symmetric encryption key k s , implementing encryption, and finally generating encrypted data E(D, k) = E a (E s (D, k s ), k p ). Throughout the data transmission, strictly follow the communication protocol specification, optimize transmission efficiency, reduce error rate, and enhance anti-interference performance with wireless communication frequency band and power adaptation strategy, ensure that the encrypted electric energy data is safely, stably, and efficiently delivered to the upper computer, effectively resist data stealing and tampering risks, and provide reliable transmission for electric energy data under low current and voltage conditions.

[0039] The data receiving module of the upper computer always maintains a listening state and receives the electric energy data transmitted by the intelligent measurement switch after encryption. Immediately start the decryption and analysis module, which uses the decryption function D = D(E(D, k), k -1 ) corresponding to the encryption function E(D, k) to generate a decryption key k -1 using the private key of the upper computer to perform reverse decryption on the encrypted data and restore the original electric energy data. According to the active power formula and the reactive power formula , carry out deep numerical integration and complex signal processing, accurately solve the active power P a and the reactive power P r . On this basis, calculate the apparent power P s according to the apparent power formula , and further calculate the electric energy error ΔE according to (where P m is the power value measured by the electric energy meter). Throughout the data processing process, effectively suppress noise interference, eliminate numerical calculation error accumulation, and correct abnormal data points in time to ensure the accuracy and reliability of the electric energy error calculation results. Finally, the display and storage module presents the power parameters and electric energy error results in an intuitive and clear visual form on the monitoring terminal screen, and according to strict data storage strategies and index architecture, safely stores the data in a large-capacity high-performance database, providing solid data support for subsequent data query, statistical analysis, trend prediction, and power management decisions, achieving efficient monitoring and accurate management of electric energy error under low current and voltage conditions.

[0040] In summary, in this embodiment, the power error testing system based on intelligent measurement switches demonstrates excellent performance under low current and voltage conditions in a small commercial office area, enabling accurate calculation and effective management of power errors. This provides highly reliable data for power system stability assessment, early fault warning, and the formulation of energy efficiency improvement strategies.

[0041] Example 2

[0042] This embodiment focuses on demonstrating the outstanding stability, reliability, and data security of the power error testing system based on intelligent measurement switches under high current and voltage conditions. Through the precise coordination of various modules of the intelligent measurement switch in a high-power environment, including the stable acquisition of strong electrical signals by the sampling module, the accurate identification of high power levels and the switching and adaptation of parameters by the command signal diversion and calibration module, the reliable encrypted transmission of data by the communication module in strong electromagnetic interference, and the precise processing and analysis by the host computer, it realizes accurate power error monitoring and efficient management in high-power power consumption scenarios such as large industrial production workshops, effectively ensuring the continuous and stable operation of industrial production and the efficient use of energy.

[0043] In practical implementation, the voltage sampling circuit and current sampling circuit of the sampling module operate stably under high current and voltage surges. The voltage sampling circuit operates according to the formula... The voltage signal U(t) is accurately acquired from the original voltage U0(t) under a strong electric environment. The current sampling circuit uses a high-current Hall sensor. Based on the Hall effect principle, under a high magnetic field strength environment, the voltage signal U(t) is obtained from the original voltage U0(t). H (t)=K H B(t)I(t) converts the large current I(t) into a voltage signal V. H (t), then through a high-gain, wide-bandwidth signal conditioning circuit and a high-speed analog-to-digital converter, according to the formula The signal is accurately converted into a digital current signal. After receiving the sampled signal, the processing module quickly calculates the instantaneous power P(t) according to the formula P(t)=U(t)×I(t). Its built-in power level discrimination mechanism determines the boundary value P of the power level interval based on in-depth mining and analysis of industrial power data. i When P(t) falls into the high power level range [P1, P2), the signal shunting and calibration module is immediately instructed to switch to the second shunting path and the second calibration parameter set. This ensures the system adapts to high current and voltage conditions, achieves precise adaptation from the signal processing front end, and guarantees the continuity and accuracy of the system's high-power energy data processing. This lays a key decision-making foundation for accurate energy monitoring in complex industrial power environments. After receiving the instruction, the signal shunting and calibration module starts the second shunting path and parameter set, with the parallel shunting resistor R... p2 With inductor L p2 The shunt resistor R plays a crucial role. p2 Based on the nonlinear correction coefficient C 21According to the formula Real-time correction of nonlinear resistance changes under high current ensures accurate shunt ratio and stable signal processing. (Inductor L) p2 With magnetic saturation correction coefficient C 22 According to formula L p2 (B L (t))=L p2 (0)(1-C 22 B L (t) 2 This system accurately compensates for magnetic saturation under high magnetic fields, optimizes signal transmission characteristics, and accurately feeds back the optimized and calibrated electrical energy signal to the processing module. This enhances the system's ability to process complex electrical energy signals under high current and voltage, ensuring the reliability of electrical energy monitoring in industrial production.

[0044] After the processed power data is sent to the communication module, it uses high-power wireless communication technology to build a robust transmission link, according to the formula... Dynamically adjust the transmit power P t Communication frequency f c To adapt to the complex electromagnetic environment and transmission distance requirements of the workshop, the communication protocol encryption process is initiated. The encryption function E(D, k) adopts a hybrid encryption method, with symmetric encryption generating a symmetric key k using the device number, timestamp, and sampling period. s Encrypt the data to get E s (D, k) s Then use the host computer's public key k p Asymmetric encryption of symmetric keys generates E(D, k) = E a (E s (D, k) s ), k p This encryption and transmission coordination mechanism ensures secure, intact, and low-error data transmission to the host computer even under strong electromagnetic interference. After receiving the encrypted data, the host computer's decryption and analysis module uses the corresponding decryption function D = D(E(D, k), k...) -1 ), generated using the private key k -1 Accurate decryption, then according to the formula The system calculates power parameters and energy errors, and finally displays and stores the data in a visual manner through the display and storage module. This provides core data-driven support for workshop equipment maintenance, energy efficiency management, and production scheduling, thereby improving the level of intelligent energy management in industrial production and ensuring the stable, economical, and green operation of the production system under high-power conditions.

[0045] In summary, the embodiment highlights the strong performance of the system in large industrial workshop high current voltage working conditions, and the intelligent measurement switch closely cooperates in each link from sampling, processing, shunt calibration to communication. The system uses special circuit, accurate algorithm and optimized parameters to cope with complex working conditions and strong interference of high-power electric energy. The deep data processing of the upper computer empowers production management. Long-term operation shows that the system is stable and reliable in high-power environment, the data transmission is safe and accurate, and the electric energy error monitoring is accurate. The system lays a solid foundation for industrial energy saving, equipment health management and production process optimization, and promotes the intelligent and refined development of industrial power management.

[0046] It is apparent to those skilled in the art that the application is not limited to the details of the foregoing exemplary embodiments, and that the application can be implemented in other particular forms without departing from the spirit or essential characteristics of the application. Therefore, the embodiments should be considered in all respects as illustrative and not restrictive, and the scope of the application should be defined by the appended claims rather than the above description, and it is intended to include all changes falling within the meaning and scope of the equivalent elements of the claims. Any reference signs in the claims should not be considered as limiting the claims involved.

Claims

1. A power error testing system based on an intelligent measuring switch, characterized in that, The system includes an intelligent measurement switch and a host computer. The intelligent measurement switch includes a sampling module, a processing module, a signal splitting and calibration module, and a communication module. The host computer is a data processing center, including a data receiving module, a decryption and analysis module, and a display and storage module. The sampling module is used to collect electrical energy data D, which includes a current signal I(t) and a voltage signal U(t). The current signal I(t) represents the instantaneous value of the current changing with time t, and the voltage signal U(t) represents the instantaneous value of the voltage changing with time t. The processing module determines the current and voltage levels based on the collected signals, analyzes the signals fed back by the signal splitting and calibration module, and transmits the data to the host computer through the communication module. The signal shunting and calibration module can automatically switch the shunting path and calibration parameters according to the judgment results of different current and voltage levels, and feedback the adjusted signal to the processing module. The manifestation of the shunting path switching is S(U(t), I(t)). When U(t)×I(t) < P1, S(U(t), I(t)) = 1, and the first shunting path and the first set of calibration parameters {C 11 , C 12 , …, C 1n} are enabled. When P1 ≤ U(t)×I(t) < P2, S(U(t), I(t)) = 2, and the second shunting path and the second set of calibration parameters {C 21 , C 22 , …, C 2m} are enabled, where P1 and P2 are power thresholds, and n and m are the numbers of calibration parameters; The communication module uses wireless communication technology to transmit data with the processing module and the host computer. During the data transmission process, a communication protocol is used to protect the data security during transmission. The communication protocol establishes communication encryption rules for the security of data transmission between the intelligent measuring switch and the host computer. The encryption function of the encryption rule is E(D, k), where k is the encryption key. The transmitted electrical energy data D is encrypted by the encryption function E(D, k) and then sent to the host computer. The data receiving module is used to receive encrypted data transmitted from the intelligent measurement switch; The decryption and analysis module is used to decrypt encrypted data and perform in-depth analysis and processing of power errors. When decrypting the data, the decryption function D = D(E(D,k), k) corresponding to the encryption function E(D,k) is used. -1 Decryption is performed, where k -1 The decryption key corresponds to the encryption key k. The energy error is the deviation between the actual energy metering value and the true energy value. The evaluation of the true energy value comprehensively considers active power, reactive power and apparent power. The display and storage module visualizes the analysis results and stores the data for querying and statistics. The first shunt path of the signal shunt and calibration module includes a precision resistor R connected in series. s1 and adjustable capacitor C s1 The first calibration parameter set {C 11 C 12 C 1n C in} 11 For precision resistor R s1 The temperature compensation coefficient is calculated, and the resistance value before compensation is R, taking into account the ambient temperature T. s1 (0), then the compensated resistance value R s1 (T)=R s1 (0)(1+C 11 T), C 12 For adjustable capacitor C s1 The frequency response correction coefficient is calculated using the input signal frequency f and the capacitive reactance when uncorrected. Modified capacitive reactance The second shunt path includes a shunt resistor R connected in parallel. p2 and inductor L p2 The second calibration parameter set {C 21 C 22 C 2m C in} 21 For shunt resistor R p2 The nonlinear correction coefficient, the current through the shunt resistor is I p2 The voltage across the terminals is U p2 The resistance value before correction is R. p2 (0), the corrected resistance value C 22 For inductor L p2 The magnetic saturation correction coefficient is obtained by using the magnetic field strength B. L (t), the inductance value before correction is L p2 (0), the corrected inductance value L p2 (B L (t))=L p2 (0)(1-C 22 B L (t) 2 ).

2. The power error testing system based on an intelligent measuring switch according to claim 1, characterized in that, The sampling module includes a voltage sampling circuit and a current sampling circuit. The voltage sampling circuit adopts a resistor voltage divider sampling structure. For the voltage divider resistors R1 and R2, the sampled voltage signal... Where U0(t) is the original voltage input signal; The current sampling circuit uses a Hall sensor, and the sensitivity of the Hall sensor is set to K. H Given a magnetic field strength of B(t) and a current of I(t) passing through the Hall sensor, the sampled voltage signal V... H (t)=K H B(t)I(t), through V H The transformation of (t) yields the current signal I(t), and the transformation relationship is as follows:

3. The power error testing system based on an intelligent measuring switch according to claim 1, characterized in that, The processing module determines the current and voltage levels by calculating the instantaneous power P(t) = U(t) × I(t), and setting the power level division intervals as [0, P1), [P1, P2), ..., [P1, P2]. i P i+1 ), where i = 1, 2, ..., when P(t) falls into the interval [0, P1), it is determined to be a low power level, corresponding to the first shunt path and the first calibration parameter set; When P(t) falls within the interval [P1, P2), it is determined to be a medium power level, corresponding to the second shunt path and the second calibration parameter set, and so on. The boundary value P of the power level division interval is... i It is determined based on statistical analysis of actual electrical energy data, that is, the number of statistical samples is N, and the power of the j-th sample is P. j , for P j After sorting, P is determined based on the sample size distribution of different power ranges. i This ensures that the number of samples within each power level division is relatively balanced, i.e. Where n i Let δ be the number of samples within the interval defined by the i-th power level, and let δ be the threshold for the difference in the number of samples.

4. The power error testing system based on an intelligent measuring switch according to claim 1, characterized in that, The communication module employs wireless communication technology, and the transmission power P of the wireless communication technology is set. t Receiver sensitivity S r Communication frequency f c Its communication distance d is related to the transmission power P t Receiver sensitivity S r and communication frequency f c The relationship is Where λ is the signal wavelength and α is the propagation loss coefficient, which is adjusted by the transmission power P. t and communication frequency f c Adaptable to different communication distance requirements.

5. The power error testing system based on an intelligent measuring switch according to claim 1, characterized in that, The encryption function E(D, k) of the communication protocol in the communication module adopts a hybrid encryption method, which includes symmetric encryption and asymmetric encryption. The symmetric encryption is achieved by symmetrically encrypting data D to obtain E. s (D, k) s ), k s The symmetric encryption key is generated by the smart measurement switch based on a pseudo-random number generator, resulting in k. s =PRNG(S1, S2, ..., S m ), where S i The seed value includes the device ID of the smart measurement switch and the current timestamp T. s and sampling period T c That is, S1 = ID, S2 = T s S3 = T c For the symmetric encryption key k s Perform asymmetric encryption, asymmetric encryption is E a (k s k p ), where k p The public key is generated by the host computer and transmitted to the intelligent measuring switch. The encrypted data is E(D, k) = E a (E s (D, k) s ), k p ).

6. The power error testing system based on an intelligent measuring switch according to claim 1, characterized in that, After decrypting the data, the decryption and analysis module of the host computer calculates the active power of the electrical energy. Where T is the integration time period, I(t) represents the instantaneous value of the current signal changing with time t, U(t) represents the instantaneous value of the voltage signal changing with time t, and reactive power... Apparent power Then the electrical energy error Where P m The power value measured by the electricity meter is compared with the standard value of electricity error ΔE0 to determine whether the electricity error range is within the normal range. The standard value of electricity error ΔE0 is determined based on statistical analysis of electricity data, that is, the statistical electricity error sample is ΔE0. j j = 1, 2, ..., J, for ΔE j After sorting, the median value within the confidence interval is taken as ΔE0.

7. The power error testing system based on an intelligent measuring switch according to claim 1, characterized in that, The processing module of the intelligent measurement switch performs self-diagnosis during operation, with a self-diagnosis cycle of T. d Every T d The sampling module, signal splitting and calibration module, and communication module are tested for functionality over time. For the sampling module, a standard voltage signal U is injected. s (t) and standard current signal I s (t), check whether the sampled value is within the error range, and set the sampling error threshold to ε. s ,when and When, where U′ s (t), I′ s If (t) represents the actual sampled value of the sampling module, then the sampling module is determined to be faulty. For the signal splitting and calibration module, check whether the splitting path switching function S(U(t), I(t)) is switched correctly and whether the calibration parameters are applied correctly. Judge by comparing the actual switching results and the data differences before and after calibration. For the communication module, the communication is normal by sending test data and checking whether the received data is complete. When a fault is detected, a fault report is generated and a fault alarm message is sent to the host computer.

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