Device and method for calibrating broadband power standard source

Abstract

The invention relates to the technical field of electromagnetic metering, and provides a broadband power standard source calibration device and method.The broadband power standard source calibration device comprises a broadband electric quantity acquisition and analysis system which comprises a main control computer, a data acquisition unit and an external synchronous clock source, and a sampling beat receiving channel of the data acquisition unit is connected with the external synchronous clock source; analysis software of the main control computer is used for analyzing and processing signals from the data acquisition unit; the broadband voltage conversion unit is connected with a first synchronous sampling channel of the data collector; the broadband current conversion unit is connected with the second synchronous sampling channel; and an automatic dynamic compensation mathematical model group for amplitude and phase is stored in analysis software of the main control computer. The broadband power standard source calibration device has the advantages that by dynamically compensating the amplitude error between channels and the phase delay between the channels of the digital collector, the conversion ratio relative error and angular difference of the broadband voltage conversion unit and the broadband current conversion unit are dynamically compensated, and the accuracy of power calibration of the broadband power standard source is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic measurement, and in particular to a calibration device and method for a broadband power standard source. Background Art

[0002] A broadband power standard source is a high-precision measurement standard device. It is a standard source that can output broadband AC and DC voltage, current and power. It is mainly used to calibrate and test broadband electrical parameter measuring instruments to ensure its measurement accuracy under various working conditions. Broadband power standard sources have important applications in many fields, especially in situations where precise electrical parameter measurements are required. For example, in the military field: used for equipment variable frequency power propulsion, power quality, electromagnetic compatibility and material properties testing; in the civilian field: in the fields of high-speed rail transmission and traction, new energy, smart grid, energy-saving lighting, etc., it is used to calibrate and test electrical parameter measurement equipment to ensure the accuracy and reliability of its measurement results; in the field of R&D and quality control: used in electrical product development, energy efficiency evaluation, quality inspection and other processes to ensure that product performance meets standard requirements.

[0003] The calibration device of the broadband power standard source is a special device used to calibrate the broadband power standard source. It is required to have high sampling performance and anti-interference performance in a broadband band, high sampling rate, high resolution and variable resolution in sampling performance, and high common mode voltage rejection ratio in anti-interference performance. Specifically speaking of functional requirements, the calibration device can accurately measure the voltage, current, phase, power, frequency, harmonics, electric energy and other characteristic parameters of the waveform of the output of the broadband power standard source.

[0004] There are many difficulties in the application scenarios of broadband power measurement, such as: 1. In the energy system efficiency test, most power conditioners use high-power switching devices. The test signal often contains high-frequency harmonics that are multiples of the device switching frequency. The high-frequency harmonics are superimposed on the fundamental wave, which will cause oscillations near the zero crossing point of the fundamental wave, making it difficult to accurately measure the signal period (or frequency). Therefore, it is generally necessary to design a line filter to filter the sampled signal by frequency characteristics to eliminate unnecessary high-frequency components superimposed on the signal. 2. In the reactor power loss test, the front end of the inverter generally includes a DC reactor for smoothing, and the back end of the inverter includes an AC inductor for harmonic suppression. Both are the main causes of power loss. Under low power factor conditions, the phase error has a significant impact on the power error. The main source of the phase error is the angular difference between the broadband voltage conversion unit (V / V) and the broadband current conversion unit (I / V), and the angular difference will change with the signal frequency, so the phase characteristic needs to be compensated. 3. The amplitude inconsistency and phase delay between channels of the data logger are related to the frequency of the measured signal. The conversion ratio and angular difference of the broadband conversion unit are also related to the frequency of the measured signal. Therefore, it is necessary to calibrate the frequency characteristics and establish a mathematical model of the "amplitude-frequency" and "phase-frequency" relationship. Then, according to the frequency of the measured signal, the amplitude and phase characteristics are automatically and dynamically compensated.

[0005] With the vigorous development of my country in the fields of new energy, electric vehicles, smart grids, etc., energy conversion efficiency testing, automotive and energy-saving home appliance inverters, energy storage system power regulators, EV inverter equipment research and development, reactor and transformer loss measurement, renewable energy system evaluation, grid interconnection and power quality all involve the accurate measurement of broadband electrical quantity or power parameters from DC (direct current) to high frequency (such as 100kHz). Therefore, there is an urgent need for the calibration device and calibration method of broadband power standard source.

[0006] As a measurement system, the calibration device of the broadband power standard source generally includes a main control computer, a data acquisition device, a signal conversion unit and other necessary components. The analysis software of the main control computer is used for data acquisition control and sampling data analysis and processing of the entire measurement system; the data acquisition device is used to perform high-bandwidth high-speed sampling of the input analog signal; the signal conversion unit is used to normalize the measured primary high voltage and large current to the input voltage of the data acquisition device. It can be estimated that the key performance indicators of the calibration device of the broadband power standard source depend on the high sampling performance of the data acquisition device and the accurate signal conversion performance of the signal conversion unit. Due to the need to carry out power measurement, the data acquisition device should have two or more synchronous sampling channels. In order to accurately control the sampling process, the data acquisition device should also have an external trigger function.

[0007] The error sources of the broadband power acquisition and analysis system established based on the sampling measurement method include: 1. The synchronization of sampling. The so-called synchronous sampling means that the discrete sequence obtained by sampling covers an integer number of cycles, otherwise it will cause spectrum leakage. In order to achieve the synchronization of sampling, on the one hand, the output signal of the signal source and the sampling beat of the data collector are synchronized to the sampling reference signal of the signal source to obtain close synchronous sampling; on the other hand, a software synchronization algorithm is developed to synchronize the sampling data and control the synchronization error within a reasonable range. 2. The gain and bandwidth of the data collector have an impact on the amplitude error. When sampling an analog signal, it is necessary to convert the high voltage and high current signals output by the signal source into a small voltage signal that can adapt to the input of the data collector through a signal conversion unit, such as a broadband voltage conversion unit (V / V) and a broadband current conversion unit (I / V). This conversion process will also bring errors. The bandwidth, conversion ratio and phase shift characteristics of the signal conversion unit will directly determine the signal amplitude error. Therefore, it is necessary to regard the data collector and the signal conversion unit as a whole, calibrate the amplitude error, and dynamically correct it by establishing a mathematical model. 3. The systematic impact of the data acquisition device quantization process, including bandwidth uncertainty, trigger uncertainty, and aperture uncertainty (mainly manifested as time base jitter), should be synthesized when evaluating their uncertainties.

[0008] In summary, the traditional calibration device of wide-band power standard source has the following shortcomings: there are signal amplitude errors and phase delays between the two synchronous sampling channels of the data acquisition device, and there are relative errors and angle differences in conversion ratios in both the wide-band voltage conversion unit and the wide-band current conversion unit. Therefore, the accuracy of the calibration device in calibrating the power of the wide-band power standard source is low. Summary of the invention

[0009] The technical problem to be solved by the present invention is to provide a calibration device and method for a wide-band power standard source, which improves the accuracy of power calibration of the wide-band power standard source by dynamically compensating for the inter-channel amplitude error and inter-channel phase delay of a digital collector, and dynamically compensating for the relative error and angular difference of the conversion ratio of a wide-band voltage conversion unit and a wide-band current conversion unit.

[0010] The present invention is implemented as follows: a calibration device for a broadband power standard source, comprising: A standard broadband power collection and analysis system comprises: a main control computer, a data collector and an external synchronous clock source, wherein a sampling beat receiving channel of the data collector is connected to the external synchronous clock source, the data collector is used to sample an input analog signal according to a set sampling beat, and then convert it into a digital signal and output it to the main control computer, and the analysis software of the main control computer is used to analyze and process the signal from the data collector; A broadband voltage conversion unit, wherein an output end of the broadband voltage conversion unit is connected to a first synchronous sampling channel of the data collector; A broadband current conversion unit, wherein the output end of the broadband current conversion unit is connected to the second synchronous sampling channel of the data collector; A broadband power standard source, as the device to be calibrated, the voltage signal output interface of the broadband power standard source is connected to the input end of the broadband voltage conversion unit, and the current signal output interface of the broadband power standard source is connected to the input end of the broadband current conversion unit; The analysis software of the main control computer stores an automatic dynamic compensation mathematical model group for amplitude and phase, and the automatic dynamic compensation mathematical model group includes a mathematical model of amplitude error between channels of a data acquisition device and analog signal frequency, a mathematical model of phase delay between channels of a data acquisition device and analog signal frequency, a mathematical model of relative error of conversion ratio of a wide-band voltage conversion unit and analog signal frequency, a mathematical model of angle difference of a wide-band voltage conversion unit and analog signal frequency, a mathematical model of relative error of conversion ratio of a wide-band current conversion unit and analog signal frequency, and a mathematical model of angle difference of a wide-band current conversion unit and analog signal frequency; The analysis software of the main control computer obtains the characteristic parameters of the electric quantity waveform from the signal from the data acquisition device, and then extracts the frequency from the characteristic parameters of the electric quantity waveform. In combination with the automatic dynamic compensation mathematical model group, the output signal of the first synchronous sampling channel is compensated and calculated to obtain the voltage amplitude and voltage phase, and the output signal of the second synchronous sampling channel is compensated and calculated to obtain the current amplitude and current phase. The power parameters for calibration are obtained from the voltage amplitude, voltage phase, current amplitude and current phase.

[0011] Furthermore, the broadband voltage conversion unit is a broadband voltage divider or a broadband voltage sensor, and the broadband current conversion unit is a broadband current divider or a broadband current sensor.

[0012] Furthermore, the sampling reference signal of the external synchronous clock source is provided by the broadband power standard source.

[0013] Furthermore, the digital model in the automatic dynamic compensation mathematical model group is a functional relationship or a numerical comparison table.

[0014] A calibration method for a broadband power standard source is provided, wherein the calibration device for a broadband power standard source is used for calibration. The calibration method comprises the following steps: S1. Create a synchronous data acquisition and analysis system: A synchronous data acquisition and analysis system, comprising: a main control computer, a data collector and an external synchronous clock source, wherein a sampling beat receiving channel of the data collector is connected to the external synchronous clock source, the data collector is used to sample an input analog signal according to a set sampling beat, and then convert it into a digital signal and output it to the main control computer, and the analysis software of the main control computer is used to analyze and process the signal from the data collector; S2. Correct the inconsistency of amplitude between channels of the synchronous data acquisition and analysis system: Setting a standard broadband signal source, the standard broadband signal source provides a standard analog signal and transmits it to the first synchronous sampling channel and the second synchronous sampling channel of the data collector at the same time; The analysis software of the main control computer obtains the amplitude of the first sampling signal from the output signal of the first synchronous sampling channel, obtains the amplitude of the second sampling signal from the output signal of the second synchronous sampling channel, and then calculates the amplitude error between the first sampling signal and the second sampling signal to obtain the amplitude error between the channels of the data acquisition device; Changing the frequency of the analog signal output from the standard broadband signal source to obtain the amplitude error between the channels of the data collector at different frequencies, thereby establishing a mathematical model of the amplitude error between the channels of the data collector and the frequency of the analog signal; S3. Correction of inter-channel phase delay in synchronous data acquisition and analysis system: The standard broadband signal source provides a standard analog signal and transmits it to the first synchronous sampling channel and the second synchronous sampling channel of the data collector at the same time; The analysis software of the main control computer obtains the initial phase of the first sampling signal from the output signal of the first synchronous sampling channel, obtains the initial phase of the second sampling signal from the output signal of the second synchronous sampling channel, and then calculates the phase delay between the second sampling signal and the first sampling signal to obtain the phase delay between the channels of the data acquisition device; Changing the frequency of the analog signal output from the standard broadband signal source to obtain the phase delay between the channels of the data collector at different frequencies, thereby establishing a mathematical model of the phase delay between the channels of the data collector and the frequency of the analog signal; S4. Create a standard broadband power collection and analysis system: The mathematical model of the amplitude error between the channels of the data collector and the analog signal frequency, and the mathematical model of the phase delay between the channels of the data collector and the analog signal frequency are compiled into an automatic dynamic compensation mathematical model group, and the automatic dynamic compensation mathematical model group is stored in the analysis software of the main control computer; S5. Calibration and compensation of conversion ratio of broadband conversion unit: An electric power standard source is provided, wherein a communication interface of the electric power standard source is connected to a communication interface of the main control computer, and an analog signal output interface of the electric power standard source is connected to the data collector via a broadband conversion unit; The communication interface of the electric energy power standard source sends the output analog signal amplitude to the communication interface of the main control computer; The conversion ratio of the broadband conversion unit is obtained by dividing the amplitude of the analog signal obtained from the communication interface of the main control computer by the amplitude of the measured signal obtained from the analysis software of the main control computer, and recorded as the actual conversion ratio; The nominal transformation ratio of the broadband transformation unit is recorded as the transformation ratio to be calibrated; Calculating a relative error between the transformation ratio to be calibrated and the actual transformation ratio; Changing the frequency of the analog signal output from the electric energy power standard source to obtain relative errors of conversion ratios at different frequencies, when the broadband conversion unit is a broadband voltage conversion unit, establishing a mathematical model of the relative error of the conversion ratio of the broadband voltage conversion unit and the analog signal frequency, and when the broadband conversion unit is a broadband current conversion unit, establishing a mathematical model of the relative error of the conversion ratio of the broadband current conversion unit and the analog signal frequency; The mathematical model of the relative error of the conversion ratio of the wide-band voltage conversion unit and the analog signal frequency, and the mathematical model of the relative error of the conversion ratio of the wide-band current conversion unit and the analog signal frequency are compiled into the automatic dynamic compensation mathematical model group; S6. Wideband conversion unit angle error calibration and compensation: The sampling reference signal interface of the electric power standard source is connected to the sampling beat receiving channel of the data collector, and the phase reference signal interface of the electric power standard source is connected to the first synchronous sampling channel of the data collector; First, the analog signal output interface of the electric power standard source is connected to the second synchronous sampling channel of the data collector, and the frequency of the analog signal output from the electric power standard source is the frequency to be calibrated of the wide-band conversion unit. At this time, the analysis software of the main control computer obtains the phase shift of the analog signal output from the electric power standard source relative to the phase reference signal, which is recorded as the reference phase shift; Then, the analog signal output interface of the electric power standard source is connected to the input end of the broadband conversion unit, and the output end of the broadband conversion unit is connected to the second synchronous sampling channel of the data collector. The frequency of the analog signal output from the electric power standard source is the frequency to be calibrated of the broadband conversion unit. At this time, the analysis software of the main control computer obtains the phase shift of the analog signal output from the broadband conversion unit relative to the phase reference signal, which is recorded as the additional phase shift. Calculating the phase difference between the additional phase shift and the reference phase shift, that is, the wideband conversion unit angle difference corresponding to the frequency to be calibrated; Changing the frequency of the analog signal output from the electric energy power standard source to obtain angle differences of different frequencies, when the broadband conversion unit is a broadband voltage conversion unit, establishing a mathematical model of the angle difference of the broadband voltage conversion unit and the analog signal frequency, when the broadband conversion unit is a broadband current conversion unit, establishing a mathematical model of the angle difference of the broadband current conversion unit and the analog signal frequency; The mathematical model of the wideband voltage conversion unit angle difference and the analog signal frequency, and the mathematical model of the wideband current conversion unit angle difference and the analog signal frequency are compiled into the automatic dynamic compensation mathematical model group; S7. Calibration device for creating a broadband power standard source: The standard broadband signal source and the electric energy power standard source are cancelled, and a broadband power standard source, a broadband voltage conversion unit and a broadband current conversion unit are added; The voltage signal output interface of the broadband power standard source is connected to the input end of the broadband voltage conversion unit, the output end of the broadband voltage conversion unit is connected to the first synchronous sampling channel of the data collector, the current signal output interface of the broadband power standard source is connected to the input end of the broadband current conversion unit, and the output end of the broadband current conversion unit is connected to the second synchronous sampling channel of the data collector; The broadband power standard source serves as a device to be calibrated, outputting an analog signal of a set power parameter, and the analog signal of the set power parameter is respectively input into a first synchronous sampling channel and a second synchronous sampling channel of the data collector through the broadband voltage conversion unit and the broadband current conversion unit, and then the analysis software of the main control computer obtains the electric quantity waveform characteristic parameter from the signal from the data collector, and then extracts the frequency from the electric quantity waveform characteristic parameter, and combines with the automatic dynamic compensation mathematical model group to perform compensation calculation on the output signal of the first synchronous sampling channel to obtain the voltage amplitude and voltage phase, and to perform compensation calculation on the output signal of the second synchronous sampling channel to obtain the current amplitude and current phase, and obtain the calibration power parameter from the voltage amplitude, voltage phase, current amplitude and current phase; Finally, the calibration power parameter is compared with the set power parameter to complete the power calibration.

[0015] Furthermore, in S6, the electric power standard source is a multifunctional signal source capable of editing high-order harmonics, and the signal output by the multifunctional signal source uses each harmonic to simulate a sine wave of different frequencies, thereby using each harmonic signal as an input signal of the wideband conversion unit at different frequencies, i.e., providing a test signal for angular difference calibration of the wideband conversion unit.

[0016] Furthermore, the analog signal output by the electric power standard source is a fundamental wave and a first harmonic, the amplitude of the fundamental wave is the same as the amplitude of the superimposed harmonic, the frequency of the harmonic is set to the frequency to be calibrated of the broadband conversion unit, the initial phase of the fundamental wave is set to 0°, and the initial phase of each calibrated harmonic is set to the same value; The order of the superimposed harmonics is changed, thereby changing the frequency of the analog signal output from the electrical energy power standard source.

[0017] Furthermore, in S6, the analog signal output by the electric power standard source is phase-locked with the sampling reference signal and the phase reference signal.

[0018] Further, in S7, the analysis software of the main control computer selects a mathematical model of a relative error of a wideband voltage conversion unit conversion ratio and a frequency of an analog signal, and a mathematical model of an angle difference of a wideband voltage conversion unit and a frequency of an analog signal from the automatic dynamic compensation mathematical model group, and performs compensation calculation on the output signal of the first synchronous sampling channel to obtain a voltage amplitude and a voltage phase; And select the mathematical model of the amplitude error between data acquisition channels and the analog signal frequency, the mathematical model of the phase delay between data acquisition channels and the analog signal frequency, the mathematical model of the relative error of the wide-band current conversion unit conversion ratio and the analog signal frequency, and the mathematical model of the wide-band current conversion unit angular difference and the analog signal frequency, and compensate the output signal of the second synchronous sampling channel to obtain the current amplitude and current phase.

[0019] Furthermore, in S7, the analysis software of the main control computer obtains the characteristic parameters of the electric quantity waveform from the signal from the data collector, which are specifically: The data collector performs pre-anti-aliasing filtering and conditioning on the analog signal from the broadband conversion unit, and the filtered signal is digitally sampled to obtain a discrete sampling sequence signal, and the discrete sampling sequence signal of one of the synchronous sampling channels is selected as the reference signal, and the reference signal is subjected to frequency characteristic filtering, and then the average fundamental frequency and fundamental zero crossing point of the reference signal are obtained. The time of the fundamental zero crossing point and the number of zero crossing points are used as the resampling trigger signal, and the resampling trigger signal is used as the sampling synchronization signal to perform resampling on the discrete sampling sequence signals from all channels of the data collector to obtain a sequence signal of an entire cycle transformation, and the main control computer performs FFT spectrum analysis calculation on the sequence signal of the entire cycle transformation to obtain the characteristic parameters of the electric quantity waveform, and the characteristic parameters of the electric quantity waveform include signal amplitude, initial phase and frequency.

[0020] Compared with the background technology, the advantages and beneficial effects of the present invention are: 1. Pre-set the automatic dynamic compensation mathematical model group in the analysis software of the main control computer. The main control computer selects corresponding parameters from the automatic dynamic compensation mathematical model group according to the analog signal frequency currently output by the calibrated device, and automatically corrects the signal from the data collector. By dynamically compensating the inter-channel amplitude error and inter-channel phase delay of the digital collector, and dynamically compensating the conversion ratio relative error and angular difference of the broadband voltage conversion unit and the broadband current conversion unit, the accuracy of power calibration of the broadband power standard source is improved.

[0021] 2. The present invention uses a standard broadband signal source to calibrate the created synchronous data acquisition and analysis system, and establishes a mathematical model of the "amplitude-frequency" and "phase-frequency" relationship based on the calibration results, so that the synchronous data acquisition and analysis system can automatically and dynamically compensate the amplitude and phase according to the frequency of the signal to be measured, eliminating the amplitude inconsistency and phase delay between channels of the data collector, thereby creating a standard broadband electrical quantity acquisition and analysis system, and providing an analysis platform for the subsequent calibration of the relative error and angular difference of the conversion ratio of the broadband voltage conversion unit and the broadband current conversion unit.

[0022] 3. The calibration method of the present invention is based on digital sampling technology and the characteristics of amplitude and phase information that can be obtained based on the Fourier analysis method. The conversion ratio and angular difference calibration of the wideband conversion unit are converted into amplitude measurement. There is no need to obtain the angular difference by directly comparing the phases of the input primary signal and the output secondary signal of the wideband conversion unit, thus realizing self-calibration and simplifying the calibration process.

[0023] 4. The calibration method of the present invention utilizes the phase reference signal of the electric power standard source as the starting point of angle difference tracing, and uses high-order harmonic signals to simulate the high-frequency sinusoidal wave signal used for calibration of the broadband conversion unit. The superimposed high-order harmonic signal can obtain phase shift information by comparing with the phase reference signal, thereby simulating the high-frequency test signal of the broadband conversion unit.

[0024] 5. The calibration method of the present invention uses a frequency characteristic filtering algorithm to solve the problem of inaccurate period (or frequency) measurement caused by oscillation of the fundamental wave zero-crossing point due to the superposition of higher harmonics, and uses the fundamental wave frequency and zero-crossing point information after frequency characteristic filtering to provide a basis for converting equally spaced sampling data into full-cycle sampling data.

[0025] 6. The calibration method of the present invention compiles the established automatic dynamic compensation mathematical model into the analysis software of the standard broadband power acquisition and analysis system, and can dynamically compensate the conversion ratio and angular difference of the broadband conversion unit according to the frequency of the measured signal, thereby realizing accurate measurement of the amplitude and phase of the measured primary signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention will be further described below in conjunction with embodiments with reference to the accompanying drawings.

[0027] Figure 1 It is a structural schematic diagram of a calibration device for a broadband power standard source of the present invention.

[0028] Figure 2 It is a hardware structure block diagram of the synchronous data acquisition and analysis system in the present invention.

[0029] Figure 3 It is a software function module block diagram of the synchronous data acquisition and analysis system in the present invention.

[0030] Figure 4 It is a principle block diagram of inter-channel amplitude consistency correction of the synchronous data acquisition and analysis system of the present invention.

[0031] Figure 5 It is a principle block diagram of inter-channel phase delay correction of the synchronous data acquisition and analysis system of the present invention.

[0032] Figure 6 It is a block diagram of the conversion ratio calibration principle of the broadband conversion unit in the present invention.

[0033] Figure 7 It is a flow chart of the polynomial fitting process in the present invention.

[0034] Figure 8 It is a block diagram of the angle difference calibration principle of the broadband conversion unit in the present invention.

[0035] Fig. 9 It is a flow chart of the frequency characteristic filtering algorithm in the present invention.

[0036] Fig.10 It is a flow chart of the angle difference calibration steps of the broadband conversion unit in the present invention.

[0037] Fig.11 It is the linear fitting flow chart in the present invention.

[0038] Fig.12 It is a schematic diagram of an analysis engine of a calibration device for a broadband power standard source in the present invention.

[0039] Fig.13 It is a flow chart of the calibration method of the broadband power standard source in the present invention. DETAILED DESCRIPTION

[0040] See also Figures 1 to 13 , which is a preferred embodiment of the present invention.

[0041] A calibration device for a broadband power standard source, comprising: A standard broadband power collection and analysis system comprises: a main control computer, a data collector and an external synchronous clock source, wherein a sampling beat receiving channel of the data collector is connected to the external synchronous clock source, the data collector is used to sample an input analog signal according to a set sampling beat, and then convert it into a digital signal and output it to the main control computer, and the analysis software of the main control computer is used to analyze and process the signal from the data collector; A broadband voltage conversion unit, wherein an output end of the broadband voltage conversion unit is connected to a first synchronous sampling channel of the data collector; A broadband current conversion unit, wherein the output end of the broadband current conversion unit is connected to the second synchronous sampling channel of the data collector; A broadband power standard source, as the device to be calibrated, the voltage signal output interface of the broadband power standard source is connected to the input end of the broadband voltage conversion unit, and the current signal output interface of the broadband power standard source is connected to the input end of the broadband current conversion unit; The analysis software of the main control computer stores an automatic dynamic compensation mathematical model group for amplitude and phase, and the automatic dynamic compensation mathematical model group includes a mathematical model of amplitude error between channels of a data acquisition device and analog signal frequency, a mathematical model of phase delay between channels of a data acquisition device and analog signal frequency, a mathematical model of relative error of conversion ratio of a wide-band voltage conversion unit and analog signal frequency, a mathematical model of angle difference of a wide-band voltage conversion unit and analog signal frequency, a mathematical model of relative error of conversion ratio of a wide-band current conversion unit and analog signal frequency, and a mathematical model of angle difference of a wide-band current conversion unit and analog signal frequency; The analysis software of the main control computer obtains the characteristic parameters of the electric quantity waveform from the signal from the data acquisition device, and then extracts the frequency from the characteristic parameters of the electric quantity waveform. In combination with the automatic dynamic compensation mathematical model group, the output signal of the first synchronous sampling channel is compensated and calculated to obtain the voltage amplitude and voltage phase, and the output signal of the second synchronous sampling channel is compensated and calculated to obtain the current amplitude and current phase. The power parameters for calibration are obtained from the voltage amplitude, voltage phase, current amplitude and current phase.

[0042] The present invention sets an automatic dynamic compensation mathematical model group in advance in the analysis software of the main control computer. The main control computer selects corresponding parameters from the automatic dynamic compensation mathematical model group according to the analog signal frequency currently output by the calibrated device, and automatically corrects the signal from the data collector. By dynamically compensating the inter-channel amplitude error and inter-channel phase delay of the digital collector, and dynamically compensating the conversion ratio relative error and angular difference of the wide-band voltage conversion unit and the wide-band current conversion unit, the accuracy of power calibration of the wide-band power standard source is improved.

[0043] The sampling beat receiving channel of the data collector is connected to the external synchronous clock source, so that the data collector has an external trigger function. The voltage signal and current signal output by the broadband power standard source are both analog signals, and the frequencies of the voltage signal and current signal are the same; the analog signal output from the broadband power standard source passes through the broadband voltage conversion unit and the broadband current conversion unit respectively, and then enters the first synchronous sampling channel and the second synchronous sampling channel of the data collector respectively, and is finally transmitted to the main control computer. The frequency of the signal does not change during the transmission process, that is, the signal frequency received by the main control computer is the same as the signal frequency output from the broadband power standard source.

[0044] The broadband voltage conversion unit is a broadband voltage divider or a broadband voltage sensor, and the broadband current conversion unit is a broadband current divider or a broadband current sensor. The broadband voltage conversion unit (V / V) inputs a high voltage signal and outputs a low voltage signal; the broadband current conversion unit (I / V) inputs a large current signal and outputs a small voltage signal; both are for adapting to the data collector. The data collector can use a variable resolution digitizer.

[0045] The sampling reference signal of the external synchronous clock source is provided by the broadband power standard source.

[0046] The digital model in the automatic dynamic compensation mathematical model group is a functional relationship or a numerical comparison table.

[0047] A method for calibrating a broadband power standard source comprises the following steps: S1. Create a synchronous data acquisition and analysis system: Combination Figure 2 and Figure 3The working principle of the synchronous data acquisition and analysis system: the analog signal is input to the variable resolution digitizer through the first synchronous sampling channel CH1 and the second synchronous sampling channel CH2. The analysis software of the main control computer reasonably configures the sampling parameters according to the characteristic parameters of the analog signal. The digitizer digitally samples the input analog signal according to the set sampling beat, reads the array composed of the sampled discrete data, selects the signal of one of the synchronous sampling channels (such as CH1) as the reference signal, and calculates the sampling synchronization signal through the reference signal through the frequency characteristic filtering algorithm. The obtained sampling synchronization signal resamples the read discrete data. The data obtained after resampling creates a data block according to the data analysis requirements (analysis time window), and the created data block performs queue synchronization operation, so the basic structure of the analysis software includes "data acquisition loop" and "data analysis loop". The data blocks in the synchronous queue perform FFT spectrum calculation to obtain the fundamental / harmonic voltage, current and power, and other waveform analysis parameters such as frequency and phase can also be obtained. The synchronous data acquisition and analysis system completes the synchronous sampling and analysis calculation of the two analog signals, and carries out subsequent function expansion and error correction based on this. The hardware structure diagram of the synchronous data acquisition and analysis system is shown in the figure below. Figure 2 The software functional module block diagram of the synchronous data acquisition and analysis system is shown in Figure 3 shown.

[0048] The main control computer uses a single-board controller with X86 architecture, the digitizer uses a PXI-1090 controller and a PXI-5922 variable-resolution digitizer, and the external clock source uses a standard signal generator. Figure 3 The analysis software has been developed to complete the software synchronization and analysis of the sampled data. The analysis functions of the software include fundamental wave effective value, harmonic effective value, fundamental wave phase, harmonic phase and other waveform characteristic parameters.

[0049] S2. Correct the inconsistency of amplitude between channels of the synchronous data acquisition and analysis system: Combination Figure 4 The characteristics of the synchronous sampling channel of the digitizer, such as input impedance, low-pass anti-aliasing filter, ADC quantization error, sampling asynchrony, sampling time base jitter, etc., will lead to differences in the amplitude measurement results between channels of the synchronous data acquisition and analysis system. To establish a standard broadband power acquisition and analysis system, it is necessary to correct the amplitude error between channels. The standard broadband signal source provides a standard analog signal, which is transmitted to the first synchronous sampling channel and the second synchronous sampling channel at the same time. Therefore, the signal amplitudes received by the first synchronous sampling channel and the second synchronous sampling channel are equal. The main control computer of the synchronous data acquisition and analysis system obtains the amplitude of the first sampling signal output from the first synchronous sampling channel CH1. A 1 and the second sampling signal amplitude output from the second synchronous sampling channel CH2A 2, and calculate the relative amplitude error between the two ∆A 2-1 , change the analog signal frequency output from the standard broadband signal source, and obtain the channel amplitude error at different frequencies ∆A f . This establishes the amplitude error between data logger channels ∆A 2-1 The mathematical model of the analog signal frequency f is used to dynamically correct the amplitude inconsistency between channels using the frequency analysis results obtained by the synchronous data acquisition and analysis system. According to the requirements of broadband power calibration, the input analog signal amplitude needs to be -5V~+5V, the frequency needs to be DC, and the channel inconsistency needs to be corrected to less than 0.001%.

[0050] The standard broadband signal source uses Fluke's 5730A high-accuracy multifunctional standard source. The output analog signal of the 5730A high-accuracy multifunctional standard source is synchronously connected to the synchronous data acquisition and analysis system. According to the amplitude measurement results of the analysis software of the main control computer and the standard value provided by the 5730A high-accuracy multifunctional standard source, the amplitude error between the synchronous sampling channels is calculated. The frequency of the output signal of the 5730A high-accuracy multifunctional standard source is changed, and the amplitude error between the synchronous sampling channels at different frequencies is calculated. According to the amplitude error calibration result, the amplitude error between the synchronous sampling channels is calculated. Figure 7 The third-order polynomial fitting method shown in the figure is used to establish a mathematical model of "amplitude-frequency" dynamic compensation.

[0051] S3. Correction of inter-channel phase delay in broadband power acquisition and analysis system: Combination Figure 5 Also, due to the difference in characteristics of the synchronous sampling channels of the digitizer, there is inevitably a phase delay between the synchronous sampling channels, which will be superimposed on the measurement system and cause system errors. The standard broadband signal source provides a standard analog signal, which is simultaneously transmitted to the first synchronous sampling channel and the second synchronous sampling channel. Therefore, the phases of the signals received by the first synchronous sampling channel and the second synchronous sampling channel are equal, that is, the standard broadband signal source outputs a 0° signal to the first synchronous sampling channel CH1 and the second synchronous sampling channel CH2 of the synchronous data acquisition and analysis system, and the phase delay between the channels is obtained by the analysis software of the main control computer. ∆Φ 2-1 , changing the frequency of the analog signal output from the standard broadband signal source to obtain the inter-channel phase delay at different frequencies ∆Φ f , thereby establishing the phase delay between data logger channels ∆ Φ f Analog signal frequency fThe mathematical model is used to dynamically correct the phase delay between channels using the frequency analysis results obtained by the synchronous data acquisition and analysis system. According to the requirements of broadband power calibration, the input analog signal amplitude needs to be -5V~+5V, the frequency needs to be DC, and the phase delay between channels needs to be corrected to less than 0.001°.

[0052] The standard broadband signal source here also uses the 5730A high-accuracy multifunctional standard source. The output analog signal is synchronously connected to the synchronous data acquisition and analysis system, providing a 0° natural phase standard. According to the phase measurement results of the analysis software of the main control computer, the phase delay between the two synchronous sampling channels is obtained. The analog signal frequency output from the 5730A high-accuracy multifunctional standard source is changed, and the phase delay between the synchronous sampling channels at different frequencies is calculated. According to the phase delay error calibration results, the phase delay error is calibrated using Fig.11 The mathematical model of “phase-frequency” dynamic compensation is established by linear fitting method.

[0053] S4. Create a standard broadband power collection and analysis system: In this embodiment, the mathematical model of the amplitude error between the data acquisition channels and the analog signal frequency, and the mathematical model of the phase delay between the data acquisition channels and the analog signal frequency do not compensate for the signal output from the first synchronous sampling channel, but only compensate for the signal output from the second synchronous sampling channel, so that the effects of the two synchronous sampling channels on the transmitted signal remain consistent.

[0054] Through step S2 and step S3, a standard broadband power acquisition and analysis system is created. The so-called "standard" means that the amplitude error between channels is better than ±0.001% and the phase delay is better than ±0.001° within the working frequency band. The "standard broadband power acquisition and analysis system" constitutes the core component of the "calibration device for broadband power standard source" on the one hand, and is used to calibrate other components of the "calibration device for broadband power standard source" on the other hand, such as the broadband voltage conversion unit and the broadband current conversion unit.

[0055] S5. Calibration and compensation of conversion ratio of broadband conversion unit: Combination Figure 6The accuracy of the conversion ratio of the wideband voltage conversion unit "V / V" and the wideband current conversion unit "I / V" directly determines the amplitude accuracy of the calibration device of the wideband power standard source, and both need to be calibrated. During the manufacturing process of the wideband voltage conversion unit "V / V" and the wideband current conversion unit "I / V", the manufacturer will mark the conversion ratio value, that is, the nominal conversion ratio, on the surface of the product after testing the manufactured products; this is convenient for customers to choose to purchase the wideband voltage conversion unit and the wideband current conversion unit according to the nominal conversion ratio according to actual needs. However, during use, when the frequency of the analog signal changes, there is a certain deviation between the actual conversion ratio of the product and the nominal conversion ratio. Therefore, in an embodiment of the present invention, it is necessary to first calibrate the conversion ratio of the wideband voltage conversion unit and the wideband current conversion unit.

[0056] Specifically, the primary input signal of the broadband conversion unit is provided by the electric power standard source. When the amplitude accuracy of the output signal of the electric power standard source is not high, a higher-level standard broadband voltmeter should be connected in parallel in the voltage channel, and a higher-level standard broadband ammeter should be connected in series in the current channel to obtain an accurate primary voltage. U and primary current I , measured value of standard broadband power acquisition and analysis system u 1 and u 2 has passed the above calibration and amplitude-frequency dynamic compensation, so the standard broadband power acquisition and analysis system can be regarded as a standard table, and the calibration result provided by it can be regarded as a standard value. The calibration result of the conversion ratio is obtained by calculation, and the actual conversion ratio is subtracted from the conversion ratio to be calibrated to obtain the relative error of the conversion ratio of the broadband conversion unit.

[0057] The communication interface of the electric power standard source is specifically connected to the communication interface of the main control computer by a GPIB line, and the processor inside the electric power standard source sends the output analog signal amplitude data to the main control computer via the GPIB line. The analog signal output interface of the electric power standard source outputs the voltage analog signal to the input end of the wide-band voltage conversion unit, and the output end of the wide-band voltage conversion unit is connected to a synchronous sampling channel of the data collector, or the analog signal output interface of the electric power standard source outputs the current analog signal to the input end of the wide-band current conversion unit, and the output end of the wide-band current conversion unit is connected to a synchronous sampling channel of the data collector.

[0058] By changing the frequency of the analog signal output from the electric power standard source and repeating the above calibration operation, the relative error of the conversion ratio at each frequency is obtained. By studying the relationship between the relative error of the conversion ratio and the frequency, a mathematical model of the relative error of the conversion ratio and the analog signal frequency is established. Figure 7The present invention adopts a polynomial fitting method. The polynomial fitting of the polynomial order of the data set (x, y) is returned by the least squares method. y is an array consisting of dependent variables, and x is an array consisting of independent variables. The polynomial fitting process requires setting the order, and the experimental data is fitted into a general form by cyclically calling the "least squares method" or "least absolute residual" or "Bisquare method", as shown in formula (1).

[0059] (1) In the formula, f is the output sequence of the best polynomial fit, x is the input sequence, a are the polynomial coefficients, m is the polynomial order. The least squares polynomial fitting adopts formula (2) to minimize the residual.

[0060] (2) In the formula, N is the length of Y, w i is the weight of i elements, f i is the best linear fit i elements, y i It is Y i When performing a linear fit, the tolerance should be set first.

[0061] The conversion ratio of the broadband conversion unit is calibrated using the constructed "standard broadband electricity collection and analysis system" and Fluke's 6100B electric energy power standard source, wherein the "standard broadband electricity collection and analysis system" serves as a standard table for measuring the secondary signal provided by the broadband conversion unit. By comparing it with the primary signal output standard value provided by the 6100B electric energy power standard source, the relative error of the conversion ratio of the broadband conversion unit can be obtained. Similar to step S2, a mathematical model for dynamic compensation related to the frequency of the signal to be measured can be established.

[0062] S6. Wideband conversion unit angle error calibration and compensation: Combination Figure 8, the basic principle of angle difference calibration: ① After the analog signal is digitized, Fourier analysis can be performed to obtain the amplitude and phase information. Therefore, the initial phase of the signal can be indirectly obtained by digitizing the amplitude of the analog signal input by sampling. In this way, there is no need to compare the two signals to obtain the angle difference, and the measurement of phase shift can be completed in one measurement channel. ② A signal source with harmonic superposition function provides test signals for angle difference calibration of the wide-band voltage conversion unit "V / V" and the wide-band current conversion unit "I / V", and high-order harmonics simulate analog sinusoidal input signals of different frequencies. ③ The internal phase reference signal of the signal source is used as the starting point for angle difference tracing, and the phase reference signal is used as a comparison reference value to obtain the reference phase shift of the fundamental wave and each harmonic of the analog signal output from the signal source relative to the phase reference signal. ④ The analog signal output from the signal source is passed through the wide-band voltage conversion unit "V / V" or the variable-frequency current conversion unit "I / V" and then compared with the phase reference signal to obtain the additional phase shift brought by the wide-band conversion unit. Then, the angular difference of the wide-band conversion unit is calculated and the superimposed harmonic order is changed to obtain the phase shift of the wide-band conversion unit under analog signals of different frequencies.

[0063] Since the angular difference of the wideband conversion unit cannot be obtained by directly comparing the phase shift of the primary signal and the secondary signal, an embodiment of the present invention provides a method for calibrating the angular difference of the wideband conversion unit, such as Figure 8 As shown, the electric power standard source provides an analog signal to output a high voltage and high current signal. The output signal of the electric power standard source is phase-locked with the internal phase reference signal and the sampling reference signal, similar to the hardware PLL. The sampling reference signal is connected to the external trigger terminal of the digitizer, and the external trigger terminal of the digitizer is the sampling beat receiving channel; the digitizer can trigger the sampling operation according to the edge of the phase reference signal. However, since the synchronization of the hardware cannot eliminate the sampling asynchrony, the sampling data needs to be synchronized. The most commonly used method is software synchronization. An embodiment of the present invention provides a frequency characteristic filtering algorithm, which selects a reference signal that is synchronized with the measured signal. The reference signal includes a start time, a sampling interval, and an instantaneous sampling value. According to the information of the measured signal, the frequency range of the fundamental wave is specified, including the upper and lower limits of the fundamental wave frequency. In order to measure the frequency of the fundamental wave, it is also necessary to redesign the low-pass filter coefficients, including parameters such as the passband edge frequency, the passband ripple, the stopband edge frequency, and the stopband attenuation. By processing the reference signal, a more accurate zero-crossing time and average fundamental frequency can be obtained. The process of the frequency characteristic filtering algorithm is as follows Fig. 9 As shown, the specific steps are as follows: ① Check whether the sampling rate and passband edge frequency of the reference signal satisfy the Nyquist sampling theorem. They should satisfy the relationship of formula (3);

[0064] Where:

[0065] ②Calculate the downsampling factor K df and downsampling frequency f ds , according to the sampling rate, upper frequency limit and stopband edge frequency of the reference signal, set the appropriate frequency range as needed to obtain K df and f ds .

[0066] ③Decimate frequency by downsampling f ds Sum signal maximum frequency f max The parameters such as frequency measurement range and set passband ripple are added with Kaiser window filter to obtain the low-pass filter coefficient.

[0067] ④ The passband edge frequency, passband ripple, stopband edge frequency and stopband attenuation parameters set by the filter design specifications are added with a Kaiser window filter to obtain the bandpass filter coefficients.

[0068] ⑤ Based on the obtained low-pass and band-pass filter coefficients, the reference signal is first subjected to low-pass FIR windowing filtering, the signal after low-pass filtering is downsampled according to the downsampling factor, and then subjected to band-pass FIR windowing filtering.

[0069] ⑥ The signal after the FIR window filtering above calculates the zero crossing point and the average fundamental frequency. The calculation result of the zero crossing point includes the time of zero crossing and the number of crossings in one cycle.

[0070] ⑦ The zero-crossing time information obtained after zero-crossing detection is used as a new sampling trigger signal to perform full-cycle sampling on the original signal, thus achieving synchronous sampling of the signal to be measured.

[0071] After the test signal for angle difference calibration is filtered by frequency characteristics, the measurement accuracy of the fundamental frequency can be improved, thereby ensuring that the whole cycle sampling of the test signal is achieved after superimposing high-order harmonics, thereby improving the accuracy of high-order harmonic phase analysis. The steps of the angle difference calibration method provided by the embodiment of the present invention are as follows: Fig.10 As shown. The starting point of the angle difference tracing is the phase reference signal. First, the fundamental and harmonic phase shifts without the conversion unit are calculated, and then the fundamental and harmonic phase shifts after the conversion unit are calculated. The additional phase shift caused by the conversion unit can be obtained through simple calculations, and the harmonics can characterize the input signals at different frequencies. Therefore, the angle difference is transferred from the phase reference signal to the harmonic phase shift after the conversion unit is connected, and finally the angle difference calibration of the signal conversion unit is realized. The angle difference of the wideband voltage conversion unit "V / V" is recorded as , the angular difference of the broadband current conversion unit "I / V" is recorded as , the angular difference (i.e., power angle) of the broadband current conversion unit “I / V” relative to the broadband voltage conversion unit “V / V” is recorded as . According to the frequency , and Based on the calibration results, a mathematical model corresponding to each angular difference and the analog signal frequency can be established. Using this mathematical model, dynamic compensation can be performed on each angular difference parameter. As an example, a method for establishing an angular difference dynamic compensation model is introduced. The present invention adopts a linear fitting method to obtain The mathematical model at different frequencies returns the linear fit of the data set (x, y) through the least squares method, where y is an array consisting of dependent variables and x is an array consisting of independent variables. The linear fitting process is to fit the experimental data into a general form by cyclically calling the least squares method and the Levenberg-Marquardt method, as shown in Equation (4).

[0072] (4) In the formula, x is the input sequence X, a is the slope, and b is the intercept. The fitting process is to obtain the values ​​of a and b. The linear fitting using the least squares method also uses the formula (2) to minimize the residual calculation method to obtain the slope and intercept of the linear model. The linear fitting process is as follows: Fig.11 shown.

[0073] like Figure 8 As shown in the figure, the constructed "standard broadband power acquisition and analysis system" and Fluke's 6100B electric power standard source are used to calibrate the angular difference of the broadband conversion unit. The phase reference signal and sampling reference signal of the 6100B electric power standard source are used. The phase reference signal is used as the reference value for phase comparison, and the sampling reference signal is used as the external trigger source of the digitizer. The phase reference signal, analog output signal and the starting phase of the sampling are phase-locked to achieve an effect similar to that of hardware PLL. At the same time, the phase reference signal, analog output signal and sampling starting phase are phase-locked to achieve an effect similar to that of hardware PLL. Fig. 9 The frequency characteristic filtering algorithm shown in the figure performs frequency characteristic filtering on the secondary output of the wideband conversion unit after superimposing the high-frequency harmonic signal, thereby realizing the full-cycle conversion of the secondary output sampling data of the wideband conversion unit. The above process realizes the angular difference calibration of the wideband conversion unit. As in step S3, a compensation mathematical model related to the frequency of the signal to be measured can be established.

[0074] The principle of angular difference calibration of the broadband voltage conversion unit and the broadband current conversion unit is described in more detail in the invention patent document with reference to publication number CN118859076A. The name of this invention patent document is a device and method for calibrating the angular difference of a broadband resistor divider.

[0075] S7. Calibration device for creating a broadband power standard source: Combination Fig.12 The working principle of the calibration device of the broadband power standard source: the signal to be measured is converted into a range by the broadband conversion unit and then input into the digitizer. Its working process is as follows: 1. First, the sampling function of the digitizer is configured. The present invention adopts the PXI-5922 variable resolution digitizer with a maximum sampling rate of 15MS / s and a maximum resolution of 24bit. The PXI-5922 uses a 6-bit 120MS / s ADC inside. The ADC integrates a noise shaping circuit, which can move the quantization noise output by the ADC from a lower frequency to a higher frequency. Then, the data from the ADC is corrected to 24-bit accuracy in real time in the digital linearization block, thereby correcting the static and dynamic errors in the ADC. The linearization block is configured during the self-calibration period. The data generated by the linearization module is subjected to a digital low-pass filter to remove all noise except a small part of the original quantization noise, and then the signal is resampled to a lower sampling frequency and a higher resolution. Before the digitizer works, basic operations such as self-calibration, initialization, setting the acquisition type, setting the vertical system, setting the horizontal system, and setting the trigger system should be completed. After the acquisition work starts, the data of each sampling point is read according to the set sampling beat, and each sampling data has an accurate time label.

[0076] 2. The digitizer performs pre-anti-aliasing filtering and signal conditioning on the voltage normalized by the wideband conversion unit to filter out noise signals outside the input bandwidth. The filtered signal enters the ADC for digitization. After digitization, a discrete sampling sequence is obtained, one of which is selected as the reference signal. The reference signal is subjected to frequency characteristic filtering. After frequency characteristic filtering, the average fundamental frequency and fundamental zero-crossing point of the reference signal are obtained. The time of the fundamental zero-crossing point and the number of zero-crossing points are used as the trigger signal for resampling. After obtaining the trigger signal, the original sampling sequence is resampled. The sequence obtained after resampling achieves the effect of whole-cycle transformation.

[0077] 3. Perform FFT spectrum analysis calculation on the data sequence after the whole cycle transformation. The result of FFT spectrum analysis can obtain the amplitude and initial phase of the fundamental wave / harmonic, and other characteristic parameters of the electric quantity waveform. According to the fundamental wave frequency and the corresponding harmonic frequencies, the amplitude and angle difference of the voltage channel and the current channel can be dynamically compensated. The result of dynamic compensation is used as the final measurement result of the wideband standard power source calibration device.

[0078] Combination Fig.13After completing steps S1 to S6, a "calibration device for a broadband power standard source" can be constructed, which consists of a "broadband conversion unit" and a "standard broadband power acquisition and analysis system", wherein the conversion ratio relative error and angle difference automatic compensation mathematical model of the broadband conversion unit has been compiled into the analysis software of the standard broadband power acquisition and analysis system. The schematic diagram of the real-time calculation processing of the analysis engine is shown in the figure below. Fig.12 As shown, the constructed wide-band power standard source calibration device can perform corresponding automatic dynamic compensation according to the characteristics of the signal to be measured, thereby obtaining accurate results.

[0079] Although the specific implementation modes of the present invention are described above, those skilled in the art should understand that the specific implementation modes described are only illustrative and are not intended to limit the scope of the present invention. Equivalent modifications and changes made by those skilled in the art in accordance with the spirit of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A calibration device for a broadband power standard source, characterized in that: include: A standard broadband power collection and analysis system comprises: a main control computer, a data collector and an external synchronous clock source, wherein a sampling beat receiving channel of the data collector is connected to the external synchronous clock source, the data collector is used to sample an input analog signal according to a set sampling beat, and then convert it into a digital signal and output it to the main control computer, and the analysis software of the main control computer is used to analyze and process the signal from the data collector; A broadband voltage conversion unit, wherein an output end of the broadband voltage conversion unit is connected to a first synchronous sampling channel of the data collector; A broadband current conversion unit, wherein the output end of the broadband current conversion unit is connected to the second synchronous sampling channel of the data collector; A broadband power standard source, as the device to be calibrated, the voltage signal output interface of the broadband power standard source is connected to the input end of the broadband voltage conversion unit, and the current signal output interface of the broadband power standard source is connected to the input end of the broadband current conversion unit; The analysis software of the main control computer stores an automatic dynamic compensation mathematical model group for amplitude and phase, and the automatic dynamic compensation mathematical model group includes a mathematical model of amplitude error between channels of a data acquisition device and analog signal frequency, a mathematical model of phase delay between channels of a data acquisition device and analog signal frequency, a mathematical model of relative error of conversion ratio of a wide-band voltage conversion unit and analog signal frequency, a mathematical model of angle difference of a wide-band voltage conversion unit and analog signal frequency, a mathematical model of relative error of conversion ratio of a wide-band current conversion unit and analog signal frequency, and a mathematical model of angle difference of a wide-band current conversion unit and analog signal frequency; The analysis software of the main control computer obtains the characteristic parameters of the electric quantity waveform from the signal from the data acquisition device, and then extracts the frequency from the characteristic parameters of the electric quantity waveform. In combination with the automatic dynamic compensation mathematical model group, the output signal of the first synchronous sampling channel is compensated and calculated to obtain the voltage amplitude and voltage phase, and the output signal of the second synchronous sampling channel is compensated and calculated to obtain the current amplitude and current phase. The power parameters for calibration are obtained from the voltage amplitude, voltage phase, current amplitude and current phase.

2. The calibration device for a broadband power standard source according to claim 1, characterized in that: The broadband voltage conversion unit is a broadband voltage divider or a broadband voltage sensor, and the broadband current conversion unit is a broadband current divider or a broadband current sensor.

3. The calibration device for a broadband power standard source according to claim 1, characterized in that: The sampling reference signal of the external synchronous clock source is provided by the broadband power standard source.

4. The calibration device for a broadband power standard source according to claim 1, characterized in that: The digital model in the automatic dynamic compensation mathematical model group is a functional relationship or a numerical comparison table.

5. A calibration method for a broadband power standard source, characterized in that: Calibration is performed using a calibration device for a broadband power standard source as claimed in any one of claims 1 to 4, wherein the calibration method comprises the following steps: S1. Create a synchronous data acquisition and analysis system: A synchronous data acquisition and analysis system, comprising: a main control computer, a data collector and an external synchronous clock source, wherein a sampling beat receiving channel of the data collector is connected to the external synchronous clock source, the data collector is used to sample an input analog signal according to a set sampling beat, and then convert it into a digital signal and output it to the main control computer, and the analysis software of the main control computer is used to analyze and process the signal from the data collector; S2. Correct the inconsistency of amplitude between channels of the synchronous data acquisition and analysis system: Setting a standard broadband signal source, the standard broadband signal source provides a standard analog signal and transmits it to the first synchronous sampling channel and the second synchronous sampling channel of the data collector at the same time; The analysis software of the main control computer obtains the first sampling signal amplitude from the output signal of the first synchronous sampling channel, obtains the second sampling signal amplitude from the output signal of the second synchronous sampling channel, and then calculates the amplitude error between the first sampling signal amplitude and the second sampling signal amplitude to obtain the amplitude error between the channels of the data acquisition device; Changing the frequency of the analog signal output from the standard broadband signal source to obtain the amplitude error between the channels of the data collector at different frequencies, thereby establishing a mathematical model of the amplitude error between the channels of the data collector and the frequency of the analog signal; S3. Correction of inter-channel phase delay in synchronous data acquisition and analysis system: The standard broadband signal source provides a standard analog signal and transmits it to the first synchronous sampling channel and the second synchronous sampling channel of the data collector at the same time; The analysis software of the main control computer obtains the initial phase of the first sampling signal from the output signal of the first synchronous sampling channel, obtains the initial phase of the second sampling signal from the output signal of the second synchronous sampling channel, and then calculates the phase delay between the second sampling signal and the first sampling signal to obtain the phase delay between the channels of the data acquisition device; Changing the frequency of the analog signal output from the standard broadband signal source to obtain the phase delay between the channels of the data collector at different frequencies, thereby establishing a mathematical model of the phase delay between the channels of the data collector and the frequency of the analog signal; S4. Create a standard broadband power collection and analysis system: The mathematical model of the amplitude error between the channels of the data collector and the analog signal frequency, and the mathematical model of the phase delay between the channels of the data collector and the analog signal frequency are compiled into an automatic dynamic compensation mathematical model group, and the automatic dynamic compensation mathematical model group is stored in the analysis software of the main control computer; S5. Wideband conversion unit conversion ratio calibration and compensation: An electric power standard source is provided, wherein a communication interface of the electric power standard source is connected to a communication interface of the main control computer, and an analog signal output interface of the electric power standard source is connected to the data collector via a broadband conversion unit; The communication interface of the electric energy power standard source sends the output analog signal amplitude to the communication interface of the main control computer; The conversion ratio of the broadband conversion unit is obtained by dividing the amplitude of the analog signal obtained from the communication interface of the main control computer by the amplitude of the measured signal obtained from the analysis software of the main control computer, and recorded as the actual conversion ratio; The nominal transformation ratio of the broadband transformation unit is recorded as the transformation ratio to be calibrated; Calculating a relative error between the transformation ratio to be calibrated and the actual transformation ratio; Changing the frequency of the analog signal output from the electric energy power standard source to obtain relative errors of conversion ratios at different frequencies, when the broadband conversion unit is a broadband voltage conversion unit, establishing a mathematical model of the relative error of the conversion ratio of the broadband voltage conversion unit and the analog signal frequency, and when the broadband conversion unit is a broadband current conversion unit, establishing a mathematical model of the relative error of the conversion ratio of the broadband current conversion unit and the analog signal frequency; The mathematical model of the relative error of the conversion ratio of the wide-band voltage conversion unit and the analog signal frequency, and the mathematical model of the relative error of the conversion ratio of the wide-band current conversion unit and the analog signal frequency are compiled into the automatic dynamic compensation mathematical model group; S6. Wideband conversion unit angle error calibration and compensation: The sampling reference signal interface of the electric power standard source is connected to the sampling beat receiving channel of the data collector, and the phase reference signal interface of the electric power standard source is connected to the first synchronous sampling channel of the data collector; First, the analog signal output interface of the electric power standard source is connected to the second synchronous sampling channel of the data collector, and the frequency of the analog signal output from the electric power standard source is the frequency to be calibrated of the wide-band conversion unit. At this time, the analysis software of the main control computer obtains the phase shift of the analog signal output from the electric power standard source relative to the phase reference signal, which is recorded as the reference phase shift; Then, the analog signal output interface of the electric power standard source is connected to the input end of the broadband conversion unit, and the output end of the broadband conversion unit is connected to the second synchronous sampling channel of the data collector. The frequency of the analog signal output from the electric power standard source is the frequency to be calibrated of the broadband conversion unit. At this time, the analysis software of the main control computer obtains the phase shift of the analog signal output from the broadband conversion unit relative to the phase reference signal, which is recorded as the additional phase shift. Calculating the phase difference between the additional phase shift and the reference phase shift, that is, the wideband conversion unit angle difference corresponding to the frequency to be calibrated; Changing the frequency of the analog signal output from the electric energy power standard source to obtain angle differences of different frequencies, when the broadband conversion unit is a broadband voltage conversion unit, establishing a mathematical model of the angle difference of the broadband voltage conversion unit and the analog signal frequency, when the broadband conversion unit is a broadband current conversion unit, establishing a mathematical model of the angle difference of the broadband current conversion unit and the analog signal frequency; The mathematical model of the wideband voltage conversion unit angle difference and the analog signal frequency, and the mathematical model of the wideband current conversion unit angle difference and the analog signal frequency are compiled into the automatic dynamic compensation mathematical model group; S7. Calibration device for creating a broadband power standard source: The standard broadband signal source and the electric energy power standard source are cancelled, and a broadband power standard source, a broadband voltage conversion unit and a broadband current conversion unit are added; The voltage signal output interface of the broadband power standard source is connected to the input end of the broadband voltage conversion unit, the output end of the broadband voltage conversion unit is connected to the first synchronous sampling channel of the data collector, the current signal output interface of the broadband power standard source is connected to the input end of the broadband current conversion unit, and the output end of the broadband current conversion unit is connected to the second synchronous sampling channel of the data collector; The broadband power standard source serves as a device to be calibrated, outputting an analog signal of a set power parameter, and the analog signal of the set power parameter is respectively input into a first synchronous sampling channel and a second synchronous sampling channel of the data collector through the broadband voltage conversion unit and the broadband current conversion unit, and then the analysis software of the main control computer obtains the electric quantity waveform characteristic parameter from the signal from the data collector, and then extracts the frequency from the electric quantity waveform characteristic parameter, and combines with the automatic dynamic compensation mathematical model group to perform compensation calculation on the output signal of the first synchronous sampling channel to obtain the voltage amplitude and voltage phase, and to perform compensation calculation on the output signal of the second synchronous sampling channel to obtain the current amplitude and current phase, and obtain the calibration power parameter from the voltage amplitude, voltage phase, current amplitude and current phase; Finally, the calibration power parameter is compared with the set power parameter to complete the power calibration.

6. The calibration method of a broadband power standard source according to claim 5, characterized in that: In S6, the electric power standard source is a multifunctional signal source capable of editing high-order harmonics. The signal output by the multifunctional signal source uses each harmonic to simulate a sine wave of different frequencies, thereby using each harmonic signal as an input signal of the wideband conversion unit at different frequencies, i.e., providing a test signal for angular difference calibration of the wideband conversion unit.

7. The calibration method of a broadband power standard source according to claim 6, characterized in that: The analog signal output by the electric power standard source is a fundamental wave and a first harmonic, the amplitude of the fundamental wave is the same as the amplitude of the superimposed harmonic, the frequency of the harmonic is set to the frequency to be calibrated of the broadband conversion unit, the initial phase of the fundamental wave is set to 0°, and the initial phase of each calibrated harmonic is set to the same value; The order of the superimposed harmonics is changed, thereby changing the frequency of the analog signal output from the electrical energy power standard source.

8. The calibration method of a broadband power standard source according to claim 5, characterized in that: In S6, the analog signal output by the electric power standard source is phase-locked with the sampling reference signal and the phase reference signal.

9. The calibration method of a broadband power standard source according to claim 5, characterized in that: In S7, the analysis software of the main control computer selects a mathematical model of a relative error of a wideband voltage conversion unit conversion ratio and a frequency of an analog signal, and a mathematical model of an angle difference of a wideband voltage conversion unit and a frequency of an analog signal from the automatic dynamic compensation mathematical model group, and performs compensation calculation on the output signal of the first synchronous sampling channel to obtain a voltage amplitude and a voltage phase; And select the mathematical model of the amplitude error between data acquisition channels and the analog signal frequency, the mathematical model of the phase delay between data acquisition channels and the analog signal frequency, the mathematical model of the relative error of the wide-band current conversion unit conversion ratio and the analog signal frequency, and the mathematical model of the wide-band current conversion unit angular difference and the analog signal frequency, and compensate the output signal of the second synchronous sampling channel to obtain the current amplitude and current phase.

10. The calibration method of a broadband power standard source according to claim 5, characterized in that: In S7, the analysis software of the main control computer obtains the characteristic parameters of the electric quantity waveform from the signal from the data collector, specifically: The data collector performs pre-anti-aliasing filtering and conditioning on the analog signal from the broadband conversion unit, and the filtered signal is digitally sampled to obtain a discrete sampling sequence signal, and the discrete sampling sequence signal of one of the synchronous sampling channels is selected as the reference signal, and the reference signal is subjected to frequency characteristic filtering, and then the average fundamental frequency and fundamental zero crossing point of the reference signal are obtained. The time of the fundamental zero crossing point and the number of zero crossing points are used as the resampling trigger signal, and the resampling trigger signal is used as the sampling synchronization signal to perform resampling on the discrete sampling sequence signals from all channels of the data collector to obtain a sequence signal of an entire cycle transformation, and the main control computer performs FFT spectrum analysis calculation on the sequence signal of the entire cycle transformation to obtain the characteristic parameters of the electric quantity waveform, and the characteristic parameters of the electric quantity waveform include signal amplitude, initial phase and frequency.

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