Electric energy meter calibration method, calibration system and electric energy meter

Abstract

The present invention provides a calibration method, a calibration system and an electric energy meter, comprising: in response to a calibration instruction sent by a verification device, obtaining chip parameters of a main control chip; the calibration instruction includes standard meter parameters; based on preset rated parameters and chip parameters, calculating a high-frequency pulse constant corresponding to the main control chip, and writing the high-frequency pulse constant into a register to initialize the electric energy meter; obtaining sampling data output by a sampling circuit after initialization, calculating a correction coefficient corresponding to the electric energy meter based on a preset correction coefficient calculation method, and correcting the electric energy meter based on the correction coefficient; calculating the error coefficient of the electric energy meter based on a preset error calculation method, and performing error correction on the electric energy meter according to the error coefficient to complete the calibration of the electric energy meter. This method can be adapted to a variety of electric energy meters, thereby improving the versatility of the calibration method and thus improving the calibration efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of electric energy meters, and in particular to an electric energy meter calibration method, a calibration system and an electric energy meter. Background Art

[0002] With the widespread application of energy meters in smart grids and energy management systems, their measurement accuracy and reliability are directly related to the efficiency of energy management and the interests of users. Energy meter calibration is a key link to ensure measurement accuracy.

[0003] Existing energy meter calibration methods usually rely on the output data of a standard meter, and adjust the registers of the energy meter through specific software to correct the measurement errors of power, phase, voltage and current. However, these methods often require complex manual participation, and energy meters with different main control chips or circuit designs need to develop calibration algorithms separately, which makes it difficult to adapt to diverse product needs. Summary of the invention

[0004] In view of this, an object of the present invention is to provide a calibration method, a calibration system and an electric energy meter for an electric energy meter, which can be adapted to a variety of electric energy meter designs, thereby improving the versatility of the calibration method, thereby reducing manual intervention and improving calibration efficiency.

[0005] In the first aspect, an embodiment of the present invention provides a calibration method for an electric energy meter, which is applied to a main control chip of the electric energy meter; the electric energy meter also includes a sampling circuit and a register respectively connected to the main control chip; the electric energy meter is communicatively connected to a verification device; the method includes: in response to a calibration instruction sent by the verification device, obtaining chip parameters of the main control chip; the calibration instruction includes standard meter parameters; based on preset ratings and chip parameters, calculating a high-frequency pulse constant corresponding to the main control chip, and writing the high-frequency pulse constant into the register to initialize the electric energy meter; obtaining sampling data output by the sampling circuit after initialization, calculating the correction coefficient corresponding to the electric energy meter based on a preset correction coefficient calculation method, and correcting the electric energy meter based on the correction coefficient; calculating the error coefficient of the electric energy meter based on a preset error calculation method, and performing error correction on the electric energy meter according to the error coefficient to complete the calibration of the electric energy meter.

[0006] Furthermore, the electric energy meter is a single-phase electric energy meter or a three-phase electric energy meter; the sampling circuit includes a current sampling circuit and a voltage sampling circuit; the preset rated parameters include a rated voltage value and a rated current value; the chip parameters include a meter constant, a clock frequency and a proportional factor; the sampling data includes a sampling current value and a sampling voltage value; and the high-frequency pulse constant is calculated by the following formula: Among them, HFCONST is the high-frequency pulse constant, U n1 is the rated voltage value of the nth sampling channel, I n1is the rated current value of the nth sampling channel, EC is the meter constant, F osc is the clock frequency, K is the scale factor, V u is the approximate current sampling value, V i is the approximate voltage sampling value; when the energy meter is a single-phase energy meter, V u =M u , where M u is the sampling voltage value; V i =M i , where M i is the sampling voltage value; when the energy meter is a three-phase energy meter, Among them, R i is the voltage divider resistor value corresponding to the voltage sampling circuit, R t is the total resistance value of the voltage divider resistor corresponding to the voltage sampling circuit, and PAGU is the ADC amplification factor of the voltage sampling circuit; Among them, CurRate is the transformer ratio, Rcy is the resistance of the secondary sampling resistor of the transformer, and PAGI is the ADC amplification factor of the current sampling circuit.

[0007] Furthermore, when the electric energy meter is a single-phase electric energy meter, the correction coefficient includes a phase angle difference gain correction value; the standard meter parameters include the standard meter active power and the standard meter reactive power; the sampling data also includes the single-phase sampling active power and the single-phase sampling reactive power; the sampling data output by the sampling circuit after initialization is obtained, and the step of calculating the correction coefficient corresponding to the electric energy meter based on the preset correction coefficient calculation method includes: calculating the phase angle difference gain correction value between the standard meter and the electric energy meter based on the following phase angle difference gain correction value calculation formula: Where θ is the phase angle difference gain correction value, T p is the active power of the standard meter, T q is the standard meter reactive power, M dp is the single-phase sampled active power, M dq It is the single-phase sampled reactive power.

[0008] Furthermore, the correction coefficient includes a power gain correction value; after the step of calculating the phase angle difference gain correction value corresponding to the electric energy meter based on the preset correction coefficient calculation method, the method further includes: based on the phase angle difference gain correction value, correcting the single-phase sampled active power to obtain the corrected single-phase sampled active power: M dp '=M dp +M dq ·θ where M dp ' is the corrected single-phase sampled active power; based on the following actual physical power value calculation formula and the corrected single-phase sampled active power, calculate the actual physical power value corresponding to the electric energy meter: Wherein, P' is the actual physical power value, C is the power scaling factor, and E is the proportional constant; the power gain correction value is calculated based on the following power gain correction value calculation formula: Among them, P gain is the power gain correction value.

[0009] Furthermore, when the electric energy meter is a three-phase electric energy meter, the correction coefficient includes a power gain correction value; the standard meter parameters include each corresponding standard meter voltage value, standard meter current value and standard meter active power; the sampled data includes a voltage register effective value and a current register effective value; the sampling data output by the sampling circuit after initialization is obtained, and the steps of calculating the correction coefficient corresponding to the electric energy meter based on a preset correction coefficient calculation method include: calculating each corresponding three-phase power coefficient in the electric energy meter based on the following power coefficient calculation formula: Among them, KP s is the three-phase power coefficient, PC is the power conversion ratio, and GC is the register adjustment ratio; multiply the voltage value of the standard meter by the current value of the standard meter to obtain the apparent power corresponding to the standard meter; calculate the corresponding three-phase apparent power in the electric energy meter based on the following apparent power calculation formula: Among them, M sp is the three-phase apparent power, RegU is the effective value of the voltage register, and RegI is the effective value of the current register; based on the following power error calculation formula, calculate each corresponding power error in the electric energy meter: Where ERR is the power error, T nsp is the apparent power corresponding to the nth sampling channel; based on the following power gain correction value calculation formula, calculate each corresponding power gain correction value in the electric energy meter: Among them, P gain is the power gain correction value.

[0010] Furthermore, when the electric energy meter is a three-phase electric energy meter, the correction coefficient includes a phase angle difference gain correction value; the sampled data also includes an effective value of an active power register; after the step of calculating the power gain correction value corresponding to the electric energy meter based on a preset correction coefficient calculation method, the method further includes: based on each corresponding power gain correction value, correcting the effective value of the active power register to obtain each corresponding corrected effective value of the active power register of the electric energy meter: RegP1=RegP·(1·P gain ), where RegP1 is the effective value of the active power register after correction, and RegP is the effective value of the active power register; based on each corresponding standard table active power and each corresponding three-phase power coefficient, the equivalent power register value corresponding to the standard table is calculated: Among them, RegP2 is the three-phase power coefficient, T npis the active power of the standard table; based on the effective value of the active power register and the active power of the standard table, each corresponding power error is updated to obtain each corresponding updated power error: Wherein, ERR' is the updated power error; based on the updated power error, each corresponding phase angle difference gain correction value is calculated: Wherein, θ is the phase angle difference gain correction value.

[0011] Furthermore, the register includes an angle difference gain register and a power gain register; the step of correcting the electric energy meter based on the correction coefficient includes: based on the following angle difference gain register format conversion formula, converting the phase angle difference gain correction value into angle difference gain register format data: Wherein, Gphs is the data in the format of the angle difference gain register; based on the following power gain register format conversion formula, the power gain correction value is converted into the data in the format of the power gain register: Among them, Gp is ​​the power gain register format data; the angle difference gain register format data is saved to the angle difference gain register; the power gain register format data is saved to the power gain register.

[0012] Furthermore, the sampled data also includes a sampled power value; the electric energy meter also includes a non-volatile register; the standard meter parameters include a standard meter voltage value, a standard meter current value and a standard meter power; based on a preset error calculation method, the error coefficient of the electric energy meter is calculated, and the electric energy meter is error corrected according to the error coefficient to complete the step of calibrating the electric energy meter, including: based on the following voltage coefficient calculation formula, the voltage coefficient corresponding to the electric energy meter is calculated: Among them, KU is the voltage coefficient, M u is the sampling voltage value, D is the accuracy adjustment factor, U n2 is the standard meter voltage value of the nth sampling channel; when the energy meter is a single-phase energy meter, D is 1000; when the energy meter is a three-phase energy meter, D is 1; based on the following current coefficient calculation formula, the current coefficient corresponding to the energy meter is calculated: Where KI is the current coefficient, M i is the sampling current value, I n2 is the standard meter voltage value of the nth sampling channel; when the electric energy meter is a single-phase electric energy meter, the one-way power coefficient corresponding to the electric energy meter is calculated based on the following one-way power coefficient calculation formula: Among them, KP d is the power factor, M p is the sampling power value, P n is the standard meter power corresponding to the nth sampling channel; the error coefficient is saved in the non-volatile register to complete the calibration of the electric energy meter.

[0013] In a second aspect, an embodiment of the present invention provides a main control chip of an electric energy meter, which is applied to the main control chip of the electric energy meter; the electric energy meter also includes a sampling circuit and a register respectively connected to the main control chip; the electric energy meter is communicatively connected to a verification device; the main control chip includes: an acquisition module, which is used to obtain chip parameters of the main control chip in response to a calibration instruction sent by the verification device; the calibration instruction includes standard meter parameters; an initialization module, which is used to calculate the high-frequency pulse constant corresponding to the main control chip based on preset rated parameters and chip parameters, and write the high-frequency pulse constant into the register to initialize the electric energy meter; a calibration module, which is used to obtain the sampling data output by the sampling circuit after initialization, calculate the correction coefficient corresponding to the electric energy meter based on a preset correction coefficient calculation method, and calibrate the electric energy meter based on the correction coefficient; the calibration module is also used to calculate the error coefficient of the electric energy meter based on a preset error calculation method, and perform error correction on the electric energy meter according to the error coefficient to complete the calibration of the electric energy meter.

[0014] In a third aspect, an embodiment of the present invention provides an electric energy meter, comprising an electric energy meter body, a main control chip, a sampling circuit and a register arranged in the electric energy meter body; and also comprising a calibration system of the electric energy meter mentioned above; the calibration system of the electric energy meter is arranged in the main control chip.

[0015] The embodiment of the present invention provides a calibration method, a calibration system and an electric energy meter for an electric energy meter, wherein the electric energy meter further comprises a sampling circuit and a register respectively connected to a main control chip; the electric energy meter is in communication connection with a verification device; the method comprises: in response to a calibration instruction sent by the verification device, obtaining chip parameters of the main control chip; the calibration instruction comprises standard meter parameters; based on preset rated parameters and chip parameters, calculating a high-frequency pulse constant corresponding to the main control chip, and writing the high-frequency pulse constant into the register to initialize the electric energy meter; obtaining sampling data output by the sampling circuit after initialization, calculating a correction coefficient corresponding to the electric energy meter based on a preset correction coefficient calculation method, and correcting the electric energy meter based on the correction coefficient; calculating an error coefficient of the electric energy meter based on a preset error calculation method, and performing error correction on the electric energy meter according to the error coefficient to complete the calibration of the electric energy meter. In this method, by calculating the high-frequency pulse constant and the correction coefficient, and correcting in combination with the parameters of the main control chip, it is possible to adapt to main control chips of different models, thereby reducing the measurement error caused by differences in sampling circuit and chip characteristics, and ensuring high-precision measurement of the electric energy meter. By calculating the error coefficient in real time and dynamically updating the power error, parameter correction can be implemented according to the characteristics of different main control chips, thereby improving the measurement accuracy and chip compatibility of the energy meter under complex load conditions. Parameters can be adjusted separately for the calibration requirements of single-phase and three-phase energy meters to adapt to different types of main control chips and energy meter structures. By storing the calibration data and correction coefficients in non-volatile registers, the data management methods of different main control chips can be adapted, thereby improving calibration efficiency and ensuring long-term stable operation.

[0016] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description, claims and drawings.

[0017] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 A flow chart of a calibration method for an electric energy meter provided in an embodiment of the present invention;

[0020] Figure 2 A schematic diagram of a current sampling channel of a single-phase electric energy meter provided in an embodiment of the present invention;

[0021] Figure 3 A schematic diagram of a voltage sampling channel of a single-phase electric energy meter provided in an embodiment of the present invention;

[0022] Figure 4 A schematic diagram of a current sampling channel of a three-phase electric energy meter provided in an embodiment of the present invention;

[0023] Figure 5 A schematic diagram of a voltage sampling channel of a three-phase electric energy meter provided in an embodiment of the present invention;

[0024] Figure 6 A schematic diagram of a calibration system for an electric energy meter provided in an embodiment of the present invention;

[0025] Figure 7 A schematic diagram of electrical energy provided for an embodiment of the present invention.

[0026] Icons: 1-acquisition module; 2-initialization module; 3-calibration module; 11-electricity meter body; 12-main control chip; 13-sampling circuit; 14-register; 15-calibration system of the electricity meter. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] To facilitate understanding of this embodiment, the embodiment of the present invention is described in detail below.

[0029] Embodiment 1:

[0030] Figure 1 A flow chart of a calibration method for an electric energy meter provided in an embodiment of the present invention.

[0031] The calibration method of the electric energy meter is applied to the main control chip of the electric energy meter; the electric energy meter also includes a sampling circuit and a register respectively connected to the main control chip; the electric energy meter is communicatively connected with the calibration device.

[0032] The electric energy meter may be a single-phase electric energy meter or a three-phase electric energy meter.

[0033] The main control chip may be a SoC chip (System on Chip) with a built-in metering function, or an MCU (Microcontroller Unit) provided with an independent metering chip and a management chip.

[0034] When the main control chip is a SoC chip, the calibration method is directly applied to the SoC chip. When the main control chip is an MCU, the calibration method is applied to the MCU. The MCU sends commands to configure data to the metering chip, and the metering chip feeds back the sampled data to the MCU for processing; the MCU calculates the calibration value through the fed-back sampled data, and then writes the parameters to be calibrated into the metering chip to complete the calibration.

[0035] Different electric energy meters correspond to different main control chips, and the chip parameters corresponding to different main control chips are also different.

[0036] The sampling circuit includes a voltage sampling circuit and a current sampling circuit. The register includes an angle difference gain register and a power gain register.

[0037] The inspection device includes a standard meter body, and the electric energy meter to be calibrated is connected to the inspection device for communication. The inspection device outputs rated parameters to the electric energy meter.

[0038] When the electric energy meter is a single-phase meter, the current sampling circuit is as follows: Figure 2 As shown, the voltage sampling circuit is as follows Figure 3 shown.

[0039] Reference Figure 2 , the single-phase meter includes two current sampling channels (IA and IB), and the standard current source is connected to the input end (CON2) of the IA channel and the IB channel respectively. The IA channel and the IB channel are calibrated independently. Each channel includes a sampling resistor network (such as RM1, RM2), a filter capacitor (such as CM2, CM3) and a corresponding current transformer input (IA+, IA- and IB+, IB-). The function of the current sampling channel is to convert the input current signal (such as 5A) into a low voltage signal (such as V1P, V1N or V2P, V2N) through a sampling circuit for processing by the main control chip. The input current signal is converted into sampling data through a transformer and a sampling resistor network (such as RM1, RM2, etc.). Filter components (such as CM2, CM3, CM4) reduce the instantaneous error caused by grid noise.

[0040] The current signal is converted into a low voltage signal (such as V1P, V1N or V2P, V2N) through the sampling resistor and the transformer. i It is the actual current signal of V1P or V2P terminal.

[0041] Reference Figure 3The voltage sampling circuit of a single-phase electric energy meter is used to reduce the input voltage (such as 220V AC voltage) to a low voltage signal suitable for the main control chip to process. The voltage sampling channel achieves accurate voltage sampling through a voltage divider resistor network (RM8-RM14) and filter capacitors (CM5, CM6), and sends the sampling signal to the input terminal (V3P, V3N) of the main control chip of the electric energy meter.

[0042] The voltage-dividing resistor network (such as RM8, RM9, and RM10) in the voltage sampling circuit reduces the input high voltage UL to a low voltage V3P. The filter capacitor (such as CM5 and CM6) eliminates high-frequency noise and ensures the stability of the sampling signal.

[0043] The sampled voltage value is the voltage value actually sampled at the V3P terminal.

[0044] Calculate the HFCONST corresponding to the IA sampling channel through the collected standard table parameters and sampling data A and KI A , calculate the HFCONST corresponding to the IB sampling channel B and KI B The high-frequency pulse constants and correction coefficients corresponding to the two sampling channels are stored in the register independently. The KU corresponding to the voltage sampling circuit is calculated and stored in the register.

[0045] Based on the sampled data, the power corresponding to each current sampling channel is calculated. Through the collected standard table parameters, the phase angle difference gain correction value, power gain correction value and one-way power coefficient are calculated and saved in the register.

[0046] When the electric energy meter is a three-phase meter, the current sampling circuit is as follows: Figure 4 As shown, the voltage sampling circuit is as follows Figure 5 shown.

[0047] Reference Figure 4 The current sampling channel of the three-phase energy meter includes three-phase input (IA, IB, IC), and each phase corresponds to an independent sampling circuit. Each channel collects current signals through current transformers (CT_A, CT_B, CT_C), and converts them into low voltage signals (IAP, IBP, ICP) through shunt resistors (such as RM8, RM24, RM37) and filter capacitors (such as CM1, CM7, CM12). After signal processing, it is sent to the main control chip for measurement.

[0048] The current signal enters the sampling circuit through the mutual inductor (CT_A, CT_B, CT_C), and is processed by the shunt resistor (such as RM8, RM24, RM37) and the filter capacitor (such as CM1, CM7, CM12) to output a low voltage signal. Each phase signal is processed independently, corresponding to the three channels IA, IB and IC respectively.

[0049] Calculate each corresponding high frequency pulse constant and write it into the register for calibration.

[0050] The three-phase sampling current is converted into low current signals (IAP, IBP, ICP) through mutual inductors and sampling resistors. i Corresponding to the sampled current value of each phase, each phase obtains an independent correction coefficient KI A KI B and KI C .

[0051] Reference Figure 5 The three-phase voltage sampling channels of the three-phase energy meter correspond to the sampling circuits of the three-phase input (LA, LB, LC). The voltage signal of each phase is processed by the voltage divider resistor network (such as RM1-RM7, RM14-RM20, RM25-RM31) and the filter capacitor (such as CM2, CM5, CM9) and converted into a low voltage signal (such as VCP, VBP, VAP) suitable for processing by the main control chip.

[0052] The three-phase voltage signal (LA, LB, LC) is reduced from a high voltage signal (such as 220V or 380V) to a low voltage signal through a voltage divider resistor network (such as RM1-RM7, RM14-RM20, RM25-RM31). The total resistance value of each phase voltage divider network (such as RM1-RM7) determines the voltage drop ratio, which is directly related to the sampling signal accuracy. Filter capacitors (such as CM2, CM5, CM9) eliminate high-frequency noise and ensure the stability of the sampling signal. The final output low-voltage signal (such as VCP, VBP, VAP) is used for processing by the main control chip. The voltage correction coefficient KU for each phase is calculated independently A , KU B and KU C , correct the measurement error.

[0053] The voltage sampling signals (VAP, VBP, VCP) and the current sampling signals (IAP, IBP, ICP) are used together for power calculation, and the error correction is based on the voltage sampling value of each phase and the standard meter voltage value.

[0054] The error correction is performed on the instantaneous power and total power of each phase, and the overall balance and measurement accuracy of the three phases are ensured by correcting the error coefficient of each phase separately.

[0055] The three-phase sampling current signals (IAP, IBP, ICP) and the voltage sampling signals are used together for power calculation, power error correction, power gain correction value calculation, and register value update for dynamic error correction.

[0056] The current sampling signal and voltage sampling signal of each phase are processed independently and calibrated separately to ensure the measurement accuracy when the three phases are unbalanced.

[0057] Reference Figure 1 , the calibration method of the electric energy meter includes:

[0058] Step S101, in response to a calibration instruction sent by a verification device, obtaining chip parameters of a main control chip; the calibration instruction includes standard meter parameters.

[0059] Here, the standard meter parameters include a standard meter voltage value, a standard meter current value, and a standard meter power.

[0060] In order to prevent errors between the rated parameters and the standard meter parameters, after setting the rated voltage value, rated current value and power factor for the standard meter body, obtain the actual standard meter parameters of the standard meter and send them to the electric energy meter through the calibration command. For example, the rated voltage value is 220V and the rated current value is 5A. At this time, the voltage value of the standard meter is 219.9V and the current value of the standard meter is 5A. The standard meter parameters are sent to the electric energy meter to be calibrated through the calibration command.

[0061] When the main control chip is a SoC chip, the chip parameters are pre-set in the SoC chip. When the main control chip is an MCU, the chip parameters are chip parameters pre-set in the metering chip.

[0062] Chip parameters include meter constant, clock frequency and scale factor.

[0063] Step S102, based on the preset rated parameters and chip parameters, the high-frequency pulse constant corresponding to the main control chip is calculated, and the high-frequency pulse constant is written into the register to initialize the electric energy meter.

[0064] Here, the rated parameters include rated current value, rated voltage value and power factor.

[0065] In one embodiment, the electric energy meter is a single-phase electric energy meter or a three-phase electric energy meter; the sampling circuit includes a current sampling circuit and a voltage sampling circuit; the preset rated parameters include a rated voltage value and a rated current value; the chip parameters include a meter constant, a clock frequency and a proportional factor; and the sampling data includes a sampled current value and a sampled voltage value.

[0066] In step S102, the high frequency pulse constant is calculated by the following formula (1):

[0067]

[0068] Among them, HFCONST is the high-frequency pulse constant, U n1 is the rated voltage value of the nth sampling channel, I n1 is the rated current value of the nth sampling channel, EC is the meter constant, F osc is the clock frequency, K is the scale factor, Vu is the approximate current sampling value, V i is the approximate voltage sampling value.

[0069] Here, the high-frequency pulse constant is a high-frequency pulse constant at a standard sampling frequency of an ADC (Analog-to-Digital Converter).

[0070] The high-frequency pulse constant is used to initialize the main control chip of the energy meter. Among them, the high-frequency pulse constant is calculated based on the sampling frequency fs of the ADC. The sampling frequency fs refers to the rate at which the analog-to-digital converter collects analog signals, usually in kHz or MHz. The standard sampling frequency is 12.8kHz. If the sampling frequency fs of the ADC changes (for example, from 12.8kHz to 25.6kHz), then the calculation result of the high-frequency pulse constant needs to be adjusted accordingly according to the multiple of the sampling frequency change. When fs increases by 1 times (such as from 12.8kHz to 25.6kHz), the value of the high-frequency pulse constant also increases by 1 times. When fs is reduced to half of the original value (such as from 12.8kHz to 6.4kHz), the value of the high-frequency pulse constant is also reduced to half of the original value.

[0071] The electric energy meter also includes an EMU module (Energy Measurement Unit Module), which is used to complete the measurement and processing of electric energy. It integrates the functions of voltage and current sampling, calculation, and storage, and is responsible for converting the collected analog signals into digital signals and calculating parameters such as power, electric energy, and power factor. The EMU module receives signals from the current sampling circuit and the voltage sampling circuit, converts the analog signals into digital signals through the internal ADC, and calculates active power, reactive power, apparent power, and electric energy based on high-frequency pulse constants. The clock frequency F osc is the clock frequency corresponding to the EMU module. When the energy meter is a three-phase energy meter, the clock frequency F osc Fixed to 4.096MHz. When the energy meter is a single-phase meter, the clock frequency F osc The default is 1MHz.

[0072] In formula (1), the proportional factor K is used to distinguish between a single-phase energy meter and a three-phase energy meter.

[0073] When the energy meter is a single-phase energy meter, Right now When the energy meter is a three-phase energy meter, Right now Among them, the current and voltage range of the three-phase energy meter is larger, and unit conversion is performed.

[0074] When the energy meter is a single-phase energy meter, V u=M u , where M u is the sampling voltage value; V i =M i , where M i is the sampled voltage value.

[0075] Here, the approximate voltage sampling value of the single-phase electric energy meter is the directly sampled voltage value, and the approximate current sampling value is the directly sampled current value.

[0076] The sampling voltage value and the sampling current value of the single-phase electric energy meter are read, the high-frequency pulse constant corresponding to each current sampling channel of the single-phase electric energy meter is calculated, and the two high-frequency pulse constants are written into the register of the main control chip.

[0077] When the energy meter is a three-phase energy meter, Among them, R i is the voltage divider resistor value corresponding to the voltage sampling circuit, R t is the total resistance value of the voltage divider resistor corresponding to the voltage sampling circuit, and PAGU is the ADC amplification factor of the voltage sampling circuit; Among them, CurRate is the transformer ratio, Rcy is the resistance of the secondary sampling resistor of the transformer, and PAGI is the ADC amplification factor of the current sampling circuit.

[0078] Here, when the electric energy meter is a three-phase electric energy meter, the chip parameters also include the resistance value of the voltage divider resistor corresponding to the voltage sampling circuit, the total resistance value of the voltage divider resistor corresponding to the voltage sampling circuit, the ADC amplification factor of the voltage sampling circuit, the transformer ratio, the resistance value of the transformer secondary sampling resistor and the ADC amplification factor of the current sampling circuit.

[0079] Calculate each corresponding high-frequency pulse constant respectively, and write the three high-frequency pulse constants into the register of the main control chip.

[0080] Step S103, acquiring sampling data output by the sampling circuit after initialization, calculating the correction coefficient corresponding to the electric energy meter based on a preset correction coefficient calculation method, and correcting the electric energy meter based on the correction coefficient.

[0081] In one embodiment, when the electric energy meter is a single-phase electric energy meter, the correction coefficient includes a phase angle difference gain correction value; the standard meter parameters include standard meter active power and standard meter reactive power; and the sampled data also includes single-phase sampled active power and single-phase sampled reactive power. Step S103 includes:

[0082] The phase angle difference gain correction value between the standard meter and the electric energy meter is calculated based on the following phase angle difference gain correction value calculation formula (2):

[0083]

[0084] Where θ is the phase angle difference gain correction value, T p is the active power of the standard meter, T q is the standard meter reactive power, M dp is the single-phase sampled active power, M dq It is the single-phase sampled reactive power.

[0085] Here, the phase angle difference gain correction value reflects the error in measuring the phase angle in the electric energy meter. It is determined by comparing the active power and reactive power of the standard meter and the electric energy meter during the calculation process. It is used to correct the deviation of the phase angle measurement and improve the metering accuracy.

[0086] In formula (2), the numerator reflects the deviation of active power and reactive power between the standard meter and the electric energy meter. The denominator balances the total power of the two to ensure that the result matches the actual error.

[0087] Furthermore, the correction coefficient includes a power gain correction value. After the step of calculating the phase angle difference gain correction value corresponding to the electric energy meter based on a preset correction coefficient calculation method, the method further includes:

[0088] Based on the phase angle difference gain correction value, the single-phase sampled active power is corrected to obtain the corrected single-phase sampled active power, as shown in the following formula (3):

[0089] M dp '=M dp +M dq ·θ (3)

[0090] Among them, M dp ' is the corrected single-phase sampled active power.

[0091] Based on the following actual physical power value calculation formula and the corrected single-phase sampled active power, the actual physical power value corresponding to the electric energy meter is calculated, as shown in the following formula (4):

[0092]

[0093] Where P' is the actual physical power value, C is the power scaling factor, and E is the proportional constant.

[0094] Here, the power scaling factor and proportional constant are used for unit adjustment and scale matching, E = 2.304 × 10 10 , C = 2 31 .

[0095] Based on the following power gain correction value calculation formula, the power gain correction value is calculated as follows:

[0096]

[0097] Among them, P gain is the power gain correction value.

[0098] Here, P gain Used to characterize the power measurement error of an electric energy meter.

[0099] In one embodiment, when the electric energy meter is a three-phase electric energy meter, the correction coefficient includes a power gain correction value; the standard meter parameters include each corresponding standard meter voltage value, standard meter current value and standard meter active power; the sampled data includes a voltage register effective value and a current register effective value. Step S103 includes:

[0100] First, calculate the corresponding three-phase power coefficient of each phase in the electric energy meter based on the following power coefficient calculation formula: Among them, KP s is the three-phase power coefficient, PC is the power conversion ratio, and GC is the register adjustment ratio.

[0101] Here, PC is the power conversion ratio, which is used to adjust the power unit and is preset to 3.6×10 6 GC is the register adjustment ratio, which reflects the proportional relationship of the register values ​​and is preset to 2 31 ×16.

[0102] Calculate each corresponding three-phase power factor separately.

[0103] Secondly, multiply the voltage value of the standard meter by the current value of the standard meter to obtain the apparent power corresponding to the standard meter.

[0104] Then, based on the following apparent power calculation formula, calculate the apparent power of each corresponding three-phase in the electric energy meter: Among them, M sp is the three-phase apparent power, RegU is the effective value of the voltage register, and RegI is the effective value of the current register.

[0105] Here, RegU is the effective value of the voltage register, reflecting the voltage sampling data. RegI is the effective value of the current register, reflecting the current sampling data. RegU and RegI are read through the energy meter sampling circuit.

[0106] Then, based on the following power error calculation formula, calculate each corresponding power error in the electric energy meter: Where ERR is the power error, T nsp is the apparent power corresponding to the nth sampling channel.

[0107] Finally, based on the following power gain correction value calculation formula, calculate each corresponding power gain correction value in the electric energy meter: Among them, P gain is the power gain correction value.

[0108] Here, based on each corresponding power error, the power gain correction values ​​of the three phases are calculated respectively.

[0109] The power measurement error of the electric energy meter is corrected by calculating the three-phase power coefficient, apparent power, power error and power gain correction value.

[0110] Each phase is calculated independently, ensuring that unbalanced conditions in the three-phase load can be accurately calibrated.

[0111] In one embodiment, when the electric energy meter is a three-phase electric energy meter, the correction coefficient includes a phase angle difference gain correction value; the sampled data also includes an effective value of an active power register. After calculating the power gain correction value corresponding to the electric energy meter based on a preset correction coefficient calculation method, the method further includes:

[0112] First, based on each corresponding power gain correction value, the effective value of the active power register is corrected to obtain each corresponding corrected effective value of the active power register of the electric energy meter: RegP1 = RegP·(1@P gain ), where RegP1 is the effective value of the active power register after correction, and RegP is the effective value of the active power register.

[0113] Here, RegP is the original active power register value read from the register of the electric energy meter. The effective value of each corresponding corrected active power register is calculated respectively.

[0114] Secondly, based on each corresponding standard table active power and each corresponding three-phase power coefficient, the equivalent power register value corresponding to the standard table is calculated: Among them, RegP2 is the three-phase power coefficient, T np It is the active power of the standard meter.

[0115] Here, each phase corresponds to a standard meter active power, and each corresponding three-phase power factor is calculated respectively.

[0116] Then, based on the effective value of the active power register and the active power of the standard table, each corresponding power error is updated to obtain each corresponding updated power error: Wherein, ERR' is the updated power error.

[0117] Here, the updated power error is calculated using the corrected register value and the equivalent value from the standard table.

[0118] Finally, based on the updated power error, each corresponding phase angle difference gain correction value is calculated: Wherein, θ is the phase angle difference gain correction value.

[0119] Here, the phase angle difference gain correction values ​​of the three phases are calculated.

[0120] By calculating the phase angle difference gain correction value, high-precision measurement of the three-phase electric energy meter under complex power grid conditions is ensured.

[0121] In one embodiment, the register includes an angle difference gain register and a power gain register.

[0122] Registers store integer data with a fixed bit width. Phase angle difference gain correction values ​​and power gain correction values ​​are usually floating point numbers. Direct storage may cause data loss or hardware parsing failure. Convert floating point numbers to register-compatible integer formats while retaining the necessary precision.

[0123] The correction coefficients (phase angle difference gain correction value and power gain correction value) are converted into format data that can be stored and processed by registers, and stored in corresponding registers.

[0124] The steps of calibrating the electric energy meter based on the correction coefficient include:

[0125] First, based on the following angle difference gain register format conversion formula, the phase angle difference gain correction value is converted into angle difference gain register format data, as shown in formula (6):

[0126]

[0127] Among them, Gphs is the angle difference gain register format data.

[0128] Here, INT[] represents a rounding function, which is used to ensure that the register stores an integer.

[0129] Obtain the phase angle difference gain correction value corresponding to the single-phase energy meter, or the phase angle difference gain correction value corresponding to the three-phase energy meter. Substitute the phase angle difference gain correction value into formula (6) to obtain a format that can be stored in the register. Write the converted Gphs into the angle difference gain register.

[0130] Secondly, based on the following power gain register format conversion formula, the power gain correction value is converted into power gain register format data as shown in the following formula (7):

[0131]

[0132] Wherein, Gp is ​​the power gain register format data.

[0133] Here, the power gain correction value corresponding to the single-phase energy meter or the power gain correction value corresponding to the three-phase energy meter is obtained. The power gain correction value is substituted into formula (6) to obtain a format that can be stored in the register. The converted Gp is ​​written into the active gain register, and the main control chip will automatically write this value into the reactive gain and apparent gain.

[0134] Finally, the angle difference gain register format data is saved to the angle difference gain register; the power gain register format data is saved to the power gain register.

[0135] The formatted Gphs is stored in the angle difference gain register to ensure that the value stored in the register can be used in real time to correct the phase angle measurement of the energy meter. The formatted Gp is ​​stored in the power gain register to ensure that the value stored in the register can be used in real time to correct the power measurement of the energy meter.

[0136] Different formulas are used for positive and negative values ​​to avoid the additional processing complexity caused by directly storing negative numbers. The data range is 2 16 and 2 15 Expanded to handle a larger range of correction values.

[0137] Step S104, calculating the error coefficient of the electric energy meter based on a preset error calculation method, and performing error correction on the electric energy meter according to the error coefficient to complete the calibration of the electric energy meter.

[0138] In one embodiment, the sampled data further includes a sampled power value; the electric energy meter further includes a non-volatile register; and the standard meter parameters include a standard meter voltage value, a standard meter current value, and a standard meter power.

[0139] The non-volatile memory may be an EEPROM (Electrically Erasable Programmable Read-Only Memory) or a ferroelectric memory. The calibration result is stored in the non-volatile memory to ensure that the data is not lost after power failure and is continuously used in subsequent operation of the electric energy meter.

[0140] The steps of step S104 include:

[0141] First, the voltage coefficient corresponding to the electric energy meter is calculated based on the following voltage coefficient calculation formula: Among them, KU is the voltage coefficient, M u is the sampling voltage value, D is the accuracy adjustment factor, U n2 is the standard meter voltage value of the nth sampling channel; when the electric energy meter is a single-phase electric energy meter, D is 1000; when the electric energy meter is a three-phase electric energy meter, D is 1.

[0142] Here, the voltage coefficient is used to correct the voltage sampling error and ensure the accuracy of voltage measurement. The accuracy of the single-phase energy meter is to 4 decimal places, so D is set to 1000 to avoid loss of accuracy after the decimal point.

[0143] Secondly, based on the following current coefficient calculation formula, the current coefficient corresponding to the electric energy meter is calculated: Where KI is the current coefficient, M i is the sampling current value, I n2 is the standard meter voltage value of the nth sampling channel.

[0144] Then, when the electric energy meter is a single-phase electric energy meter, the one-way power coefficient corresponding to the electric energy meter is calculated based on the following one-way power coefficient calculation formula: Among them, KP d is the power factor, M p is the sampling power value, P n is the standard meter power corresponding to the nth sampling channel.

[0145] Finally, the error coefficients are saved to nonvolatile registers to complete the calibration of the energy meter.

[0146] Single-phase energy meter corresponding calculation to obtain KU, KI and KP d , the calculated KU, KI and KP d The non-volatile memory is written to complete the calibration of the electric energy meter. The first channel and the second channel of the single-phase electric energy meter are calculated respectively, and the calibration principle is the same.

[0147] KU and KI are calculated for the three phases A, B, and C of the three phase energy meter, and the calculated KU and KI are written into the non-volatile memory. The three phase calibration is performed cyclically to ensure that each phase is calibrated independently.

[0148] A calibration method for an electric energy meter provided in an embodiment of the present invention is applied to a main control chip of the electric energy meter; the electric energy meter also includes a sampling circuit and a register respectively connected to the main control chip; the electric energy meter is in communication connection with a verification device; the method includes: in response to a calibration instruction sent by the verification device, obtaining chip parameters of the main control chip; the calibration instruction includes standard meter parameters; based on preset rated parameters and chip parameters, calculating the high-frequency pulse constant corresponding to the main control chip, and writing the high-frequency pulse constant into the register to initialize the electric energy meter; obtaining the sampling data output by the sampling circuit after initialization, calculating the correction coefficient corresponding to the electric energy meter based on a preset correction coefficient calculation method, and correcting the electric energy meter based on the correction coefficient; calculating the error coefficient of the electric energy meter based on a preset error calculation method, and performing error correction on the electric energy meter according to the error coefficient to complete the calibration of the electric energy meter. In this method, by calculating the high-frequency pulse constant and the correction coefficient, and correcting in combination with the characteristic parameters of the main control chip, it can adapt to different models of main control chips, thereby reducing the measurement error caused by the sampling circuit and chip characteristic differences, and ensuring high-precision measurement of the electric energy meter. By calculating the error coefficient in real time and dynamically updating the power error, parameter correction can be implemented according to the characteristics of different main control chips, thereby improving the measurement accuracy and chip compatibility of the energy meter under complex load conditions. Parameters can be adjusted separately for the calibration requirements of single-phase and three-phase energy meters to adapt to different types of main control chips and energy meter structures. By storing the calibration data and correction coefficients in non-volatile registers, the data management methods of different main control chips can be adapted, thereby improving calibration efficiency and ensuring long-term stable operation.

[0149] Embodiment 2:

[0150] Figure 6 A schematic diagram of a calibration system for an electric energy meter provided in an embodiment of the present invention.

[0151] The calibration system of the electric energy meter is arranged in the electric energy meter, and the electric energy meter also comprises a sampling circuit and a register respectively connected with the main control chip; the electric energy meter is communicatively connected with the calibration device.

[0152] Reference Figure 6 , the calibration system of the electric energy meter includes:

[0153] The acquisition module 1 is used to obtain chip parameters of the main control chip in response to the calibration instruction sent by the verification device; the calibration instruction includes standard meter parameters.

[0154] The initialization module 2 is used to calculate the high-frequency pulse constant corresponding to the main control chip based on the preset rated parameters and chip parameters, and write the high-frequency pulse constant into the register to initialize the electric energy meter.

[0155] The calibration module 3 is used to obtain the sampling data output by the sampling circuit after initialization, calculate the correction coefficient corresponding to the electric energy meter based on a preset correction coefficient calculation method, and calibrate the electric energy meter based on the correction coefficient.

[0156] The calibration module 3 is further used to calculate the error coefficient of the electric energy meter based on a preset error calculation method, and perform error correction on the electric energy meter according to the error coefficient to complete the calibration of the electric energy meter.

[0157] In one embodiment, the electric energy meter is a single-phase electric energy meter or a three-phase electric energy meter; the sampling circuit includes a current sampling circuit and a voltage sampling circuit; the preset rated parameters include a rated voltage value and a rated current value; the chip parameters include a meter constant, a clock frequency and a proportional factor; and the sampling data includes a sampled current value and a sampled voltage value. Initialization module 2 is also used to:

[0158] The high frequency pulse constant is calculated by the following formula:

[0159]

[0160] Among them, HFCONST is the high-frequency pulse constant, U n1 is the rated voltage value of the nth sampling channel, I n1 is the rated current value of the nth sampling channel, EC is the meter constant, F osc is the clock frequency, K1 is the scale factor, V u is the approximate current sampling value, V i is the approximate voltage sampling value;

[0161] When the energy meter is a single-phase energy meter, V u =M u , where M u is the sampling voltage value; V i =M i , where M i is the sampled voltage value.

[0162] When the energy meter is a three-phase energy meter, Among them, R i is the voltage divider resistor value corresponding to the voltage sampling circuit, R t is the total resistance value of the voltage divider resistor corresponding to the voltage sampling circuit, and PAGU is the ADC amplification factor of the voltage sampling circuit; Among them, CurRate is the transformer ratio, Rcy is the resistance of the secondary sampling resistor of the transformer, and PAGI is the ADC amplification factor of the current sampling circuit.

[0163] In one embodiment, when the electric energy meter is a single-phase electric energy meter, the correction coefficient includes a phase angle difference gain correction value; the standard meter parameters include standard meter active power and standard meter reactive power; and the sampled data also includes single-phase sampled active power and single-phase sampled reactive power. The calibration module 3 is also used for:

[0164] The phase angle difference gain correction value between the standard meter and the electric energy meter is calculated based on the following phase angle difference gain correction value calculation formula:

[0165]

[0166] Where θ is the phase angle difference gain correction value, T p is the active power of the standard meter, T q is the standard meter reactive power, M dp is the single-phase sampled active power, M dq It is the single-phase sampled reactive power.

[0167] The correction coefficient includes a power gain correction value. The calibration module 3 is also used for:

[0168] Based on the phase angle difference gain correction value, the single-phase sampled active power is corrected to obtain the corrected single-phase sampled active power:

[0169] M dp '=M dp +M dq ·θ

[0170] Among them, M dp ' is the corrected single-phase sampled active power.

[0171] Based on the following actual physical power value calculation formula and the corrected single-phase sampled active power, calculate the actual physical power value corresponding to the electric energy meter:

[0172]

[0173] Where P' is the actual physical power value, C is the power scaling factor, and E is the proportional constant.

[0174] Calculate the power gain correction value based on the following power gain correction value calculation formula:

[0175]

[0176] Among them, P gain is the power gain correction value.

[0177] In one embodiment, when the electric energy meter is a three-phase electric energy meter, the correction coefficient includes a power gain correction value; the standard meter parameters include each corresponding standard meter voltage value, standard meter current value and standard meter active power; the sampled data includes a voltage register effective value and a current register effective value. The calibration module 3 is also used to:

[0178] Based on the following power factor calculation formula, calculate the corresponding three-phase power factor of each phase in the electric energy meter: Among them, KP s is the three-phase power coefficient, PC is the power conversion ratio, and GC is the register adjustment ratio.

[0179] Multiply the voltage value of the standard meter by the current value of the standard meter to obtain the apparent power corresponding to the standard meter.

[0180] Based on the following apparent power calculation formula, calculate the apparent power of each corresponding three-phase in the electric energy meter: Among them, M sp is the three-phase apparent power, RegU is the effective value of the voltage register, RegI is the effective value of the current register,

[0181] Based on the following power error calculation formula, calculate each corresponding power error in the electric energy meter: Where ERR is the power error, T nsp is the apparent power corresponding to the nth sampling channel.

[0182] Based on the following power gain correction value calculation formula, calculate each corresponding power gain correction value in the electric energy meter: Among them, P gain is the power gain correction value.

[0183] In one embodiment, when the electric energy meter is a three-phase electric energy meter, the correction coefficient includes a phase angle difference gain correction value; and the sampled data also includes an effective value of an active power register. The calibration module 3 is further used for:

[0184] Based on each corresponding power gain correction value, the effective value of the active power register is corrected to obtain each corresponding corrected effective value of the active power register of the electric energy meter: RegP1 = RegP·(1·P gain ), where RegP1 is the effective value of the active power register after correction, and RegP is the effective value of the active power register.

[0185] Based on each corresponding standard table active power and each corresponding three-phase power coefficient, the equivalent power register value corresponding to the standard table is calculated: Among them, RegP2 is the three-phase power coefficient, T np It is the active power of the standard meter.

[0186] Based on the effective value of the active power register and the active power in the standard table, each corresponding power error is updated to obtain each corresponding updated power error: Wherein, ERR' is the updated power error.

[0187] Based on the updated power error, each corresponding phase angle difference gain correction value is calculated: Wherein, θ is the phase angle difference gain correction value.

[0188] In one embodiment, the register includes an angle difference gain register and a power gain register. The calibration module 3 is also used for:

[0189] Based on the following angle difference gain register format conversion formula, the phase angle difference gain correction value is converted into angle difference gain register format data: Among them, Gphs is the angle difference gain register format data.

[0190] Based on the following power gain register format conversion formula, the power gain correction value is converted into power gain register format data: Wherein, Gp is ​​the power gain register format data.

[0191] The angle difference gain register format data is saved to the angle difference gain register; the power gain register format data is saved to the power gain register.

[0192] In one embodiment, the sampled data also includes a sampled power value; the electric energy meter also includes a non-volatile register; and the standard meter parameter also includes a standard meter power. The calibration module 3 is further used for:

[0193] Based on the following voltage coefficient calculation formula, the voltage coefficient corresponding to the electric energy meter is calculated: Among them, KU is the voltage coefficient, M u is the sampling voltage value, D is the accuracy adjustment factor, U n2 is the standard meter voltage value of the nth sampling channel; when the electric energy meter is a single-phase electric energy meter, D is 1000; when the electric energy meter is a three-phase electric energy meter, D is 1.

[0194] Based on the following current coefficient calculation formula, the current coefficient corresponding to the electric energy meter is calculated: Where KI is the current coefficient, M i is the sampling current value, I n2 is the standard meter voltage value of the nth sampling channel.

[0195] When the electric energy meter is a single-phase electric energy meter, the one-way power coefficient corresponding to the electric energy meter is calculated based on the following one-way power coefficient calculation formula: Among them, KPd is the power factor, M p is the sampling power value, P n is the standard meter power corresponding to the nth sampling channel.

[0196] The error coefficients are saved to nonvolatile registers to complete the calibration of the energy meter.

[0197] The embodiment of the present invention provides a calibration system for an electric energy meter, which can adjust parameters according to the calibration requirements of single-phase and three-phase electric energy meters, so as to adapt to different types of main control chips and electric energy meter structures. By storing calibration data and correction coefficients in non-volatile registers, the data management methods of different main control chips can be adapted, thereby improving calibration efficiency and ensuring long-term stable operation.

[0198] Embodiment three:

[0199] Figure 7 A schematic diagram of a calibration system for an electric energy meter provided in an embodiment of the present invention.

[0200] Reference Figure 7 The electric energy meter includes an electric energy meter body 11, a main control chip 12, a sampling circuit 13 and a register 14 arranged in the electric energy meter body 11; and also includes the above-mentioned electric energy meter calibration system 15; the electric energy meter calibration system 15 is arranged in the main control chip 12.

[0201] The electric energy meter provided in the embodiment of the present invention realizes automatic calibration and real-time error correction through the main control chip, which significantly improves the measurement accuracy and adaptability; the dynamic initialization of the high-frequency pulse constant ensures the long-term stability of the electric energy meter in a complex power grid environment; the integrated design reduces manual intervention and improves the convenience and reliability of use.

[0202] The computer program product provided in the embodiment of the present invention includes a computer-readable storage medium storing program code. The instructions included in the program code can be used to execute the method described in the previous method embodiment. The specific implementation can be found in the method embodiment and will not be repeated here.

[0203] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the system and device described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0204] In addition, in the description of the embodiments of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0205] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program codes.

[0206] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0207] Finally, it should be noted that the above-described embodiments are only specific implementations of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention is described in detail with reference to the above-described embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-described embodiments within the technical scope disclosed by the present invention, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for calibrating an electric energy meter, characterized in that: A main control chip applied to an electric energy meter; the electric energy meter further comprises a sampling circuit and a register respectively connected to the main control chip; the electric energy meter is communicatively connected to a verification device; the method comprises: In response to the calibration instruction sent by the verification device, the chip parameters of the main control chip are obtained; the calibration instruction includes standard meter parameters; Based on the preset rated parameters and the chip parameters, a high-frequency pulse constant corresponding to the main control chip is calculated, and the high-frequency pulse constant is written into the register to initialize the electric energy meter; Acquire sampling data output by the sampling circuit after initialization, calculate the correction coefficient corresponding to the electric energy meter based on a preset correction coefficient calculation method, and calibrate the electric energy meter based on the correction coefficient; Based on a preset error calculation method, the error coefficient of the electric energy meter is calculated, and the error correction of the electric energy meter is performed according to the error coefficient to complete the calibration of the electric energy meter.

2. The method for calibrating an electric energy meter according to claim 1, characterized in that: The electric energy meter is a single-phase electric energy meter or a three-phase electric energy meter; the sampling circuit includes a current sampling circuit and a voltage sampling circuit; the preset rated parameters include a rated voltage value and a rated current value; the chip parameters include a meter constant, a clock frequency and a proportional factor; the sampling data includes a sampled current value and a sampled voltage value; The high frequency pulse constant is calculated by the following formula: Among them, HFCONST is the high frequency pulse constant, U n1 is the rated voltage value of the nth sampling channel, I n1 is the rated current value of the nth sampling channel, EC is the meter constant, F osc is the clock frequency, K is the scale factor, V u is the approximate current sampling value, V i is the approximate voltage sampling value; When the electric energy meter is the single-phase electric energy meter, V u =M u , where M u is the sampled voltage value; V i =M i , where M i is the sampled voltage value; When the electric energy meter is the three-phase electric energy meter, Among them, R i is the voltage divider resistor value corresponding to the voltage sampling circuit, R t is the total resistance value of the voltage divider resistors corresponding to the voltage sampling circuit, and PAGU is the ADC amplification factor of the voltage sampling circuit; Wherein, CurRate is the transformer ratio, Rcy is the resistance of the secondary sampling resistor of the transformer, and PAGI is the ADC amplification factor of the current sampling circuit.

3. The method for calibrating an electric energy meter according to claim 2, characterized in that: When the electric energy meter is a single-phase electric energy meter, the correction coefficient includes a phase angle difference gain correction value; the standard meter parameters include standard meter active power and standard meter reactive power; the sampled data also includes single-phase sampled active power and single-phase sampled reactive power; The step of obtaining the sampling data output by the sampling circuit after initialization and calculating the correction coefficient corresponding to the electric energy meter based on a preset correction coefficient calculation method comprises: The phase angle difference gain correction value between the standard meter and the electric energy meter is calculated based on the following phase angle difference gain correction value calculation formula: Wherein, θ is the phase angle difference gain correction value, T p is the standard table active power, T q is the standard reactive power, M dp is the single-phase sampled active power, M dq The reactive power is sampled for the single phase.

4. The method for calibrating an electric energy meter according to claim 3, characterized in that: The correction coefficient includes a power gain correction value; After the step of calculating the phase angle difference gain correction value corresponding to the electric energy meter based on a preset correction coefficient calculation method, the method further includes: Based on the phase angle difference gain correction value, the single-phase sampled active power is corrected to obtain the corrected single-phase sampled active power: M dp '=M dp +M dq ·θ Among them, M dp ' is the corrected single-phase sampled active power; Based on the following actual physical power value calculation formula and the corrected single-phase sampled active power, the actual physical power value corresponding to the electric energy meter is calculated: Wherein, P' is the actual physical power value, C is the power scaling factor, and E is the proportional constant; The power gain correction value is calculated based on the following power gain correction value calculation formula: Among them, P gain is the power gain correction value.

5. The method for calibrating an electric energy meter according to claim 2, characterized in that: When the electric energy meter is a three-phase electric energy meter, the correction coefficient includes a power gain correction value; the standard meter parameters include each corresponding standard meter voltage value, standard meter current value and standard meter active power; the sampled data includes a voltage register effective value and a current register effective value; The step of obtaining the sampling data output by the sampling circuit after initialization and calculating the correction coefficient corresponding to the electric energy meter based on a preset correction coefficient calculation method comprises: Based on the following power coefficient calculation formula, calculate each corresponding three-phase power coefficient in the electric energy meter: Among them, KP s is the three-phase power coefficient, PC is the power conversion ratio, and GC is the register adjustment ratio; Multiplying the voltage value of the standard meter by the current value of the standard meter to obtain the apparent power corresponding to the standard meter; Based on the following apparent power calculation formula, calculate the corresponding three-phase apparent power in the electric energy meter: Among them, M sp is the three-phase apparent power, RegU is the effective value of the voltage register, and RegI is the effective value of the current register; Based on the following power error calculation formula, each corresponding power error in the electric energy meter is calculated: Where ERR is the power error, T nsp is the apparent power corresponding to the nth sampling channel; Based on the following power gain correction value calculation formula, each corresponding power gain correction value in the electric energy meter is calculated: Among them, P gain is the power gain correction value.

6. The method for calibrating an electric energy meter according to claim 5, characterized in that: When the electric energy meter is a three-phase electric energy meter, the correction coefficient includes a phase angle difference gain correction value; the sampled data also includes an effective value of an active power register; After the step of calculating the power gain correction value corresponding to the electric energy meter based on a preset correction coefficient calculation method, the method further includes: Based on each corresponding power gain correction value, the effective value of the active power register is corrected to obtain each corresponding corrected effective value of the active power register of the electric energy meter: RegP1=RegP·(1·P gain ), wherein RegP1 is the effective value of the active power register after correction, and RegP is the effective value of the active power register; Based on each corresponding active power of the standard table and each corresponding three-phase power coefficient, the equivalent power register value corresponding to the standard table is calculated: Wherein, RegP2 is the three-phase power coefficient, T np is the active power of the standard meter; Based on the effective value of the active power register and the active power of the standard table, each corresponding power error is updated to obtain each corresponding updated power error: Wherein, ERR' is the updated power error; Based on the updated power error, each corresponding phase angle difference gain correction value is calculated: Wherein, θ is the phase angle difference gain correction value.

7. The method for calibrating an electric energy meter according to claim 4 or 6, characterized in that: The registers include an angle difference gain register and a power gain register; The step of calibrating the electric energy meter based on the correction coefficient comprises: Based on the following angle difference gain register format conversion formula, the phase angle difference gain correction value is converted into angle difference gain register format data: Wherein, Gphs is the angle difference gain register format data; The power gain correction value is converted into power gain register format data based on the following power gain register format conversion formula: Wherein, Gp is ​​the power gain register format data; The angle difference gain register format data is saved in the angle difference gain register; and the power gain register format data is saved in the power gain register.

8. The method for calibrating an electric energy meter according to claim 2, characterized in that: The sampled data also includes a sampled power value; the electric energy meter also includes a non-volatile register; the standard meter parameters include a standard meter voltage value, a standard meter current value and a standard meter power; The step of calculating the error coefficient of the electric energy meter based on a preset error calculation method, and performing error correction on the electric energy meter according to the error coefficient to complete the calibration of the electric energy meter includes: Based on the following voltage coefficient calculation formula, the voltage coefficient corresponding to the electric energy meter is calculated: Where KU is the voltage coefficient, M u is the sampled voltage value, D is the accuracy adjustment factor, U n2 is the standard meter voltage value of the nth sampling channel; wherein, when the electric energy meter is a single-phase electric energy meter, D is 1000; when the electric energy meter is a three-phase electric energy meter, D is 1; Based on the following current coefficient calculation formula, the current coefficient corresponding to the electric energy meter is calculated: Wherein, KI is the current coefficient, M i is the sampling current value, I n2 is the standard meter voltage value of the nth sampling channel; When the electric energy meter is the single-phase electric energy meter, the one-way power coefficient corresponding to the electric energy meter is calculated based on the following one-way power coefficient calculation formula: Among them, KP d is the power coefficient, M p is the sampled power value, P n is the standard meter power corresponding to the nth sampling channel; The error coefficient is saved in the non-volatile register to complete the calibration of the electric energy meter.

9. A calibration system for an electric energy meter, characterized in that: A main control chip applied to an electric energy meter; the electric energy meter further comprises a sampling circuit and a register respectively connected to the main control chip; the electric energy meter is communicatively connected to the verification device; the main control chip comprises: An acquisition module, used for acquiring chip parameters of the main control chip in response to a calibration instruction sent by the verification device; the calibration instruction includes standard meter parameters; An initialization module, used for calculating the high-frequency pulse constant corresponding to the main control chip based on preset rated parameters and the chip parameters, and writing the high-frequency pulse constant into the register to initialize the electric energy meter; A calibration module, used to obtain the sampling data output by the sampling circuit after initialization, calculate the correction coefficient corresponding to the electric energy meter based on a preset correction coefficient calculation method, and calibrate the electric energy meter based on the correction coefficient; The calibration module is further used to calculate the error coefficient of the electric energy meter based on a preset error calculation method, and perform error correction on the electric energy meter according to the error coefficient to complete the calibration of the electric energy meter.

10. An electric energy meter, characterized in that: It comprises an electric energy meter body, a main control chip, a sampling circuit and a register arranged in the electric energy meter body; and also comprises a calibration system of the electric energy meter as claimed in claim 9; the calibration system of the electric energy meter is arranged in the main control chip.

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