A commutation measurement method and device based on differential sampling

Abstract

The present invention discloses a phase-changing measurement method and device based on differential sampling, the method comprising: performing phase-changing sampling on the difference between a sinusoidal voltage and an initial alternating current quantum voltage based on an initial sampling parameter to obtain an initial difference voltage; optimizing the initial alternating current quantum voltage and the initial sampling parameter based on the initial difference voltage; performing phase-changing sampling on the difference between a sinusoidal voltage and an optimized initial alternating current quantum voltage based on the optimized initial sampling parameter to obtain an optimized difference voltage; and providing the amplitude and phase of the sinusoidal voltage based on the optimized alternating current quantum voltage and the optimized difference voltage. The present invention can reduce the measurement error when measuring an alternating current signal through differential sampling.

Description

Technical Field

[0001] The invention belongs to the technical field of voltage signal measurement, and relates to a commutation measurement method and device based on differential sampling. Background Art

[0002] In order to achieve precise measurement of the amplitude and phase of AC signals, AC sampling technology is widely used in the measurement of AC electrical quantities. However, due to the existence of hysteresis effects, the accuracy of AC sampling methods is limited. In order to reduce the gain error and nonlinear effects of sampling digital meters, an effective way is to measure lower voltage amplitudes. Therefore, with the emergence of AC quantum step wave signals, AC differential sampling methods were proposed.

[0003] Differential sampling is a method of using a digital meter to sample the difference between the sinusoidal voltage and the step wave signal generated by the AC source. In this differential sampling scheme, the digital meter samples the difference voltage to achieve attenuation of measurement errors.

[0004] At the same time, in order to reduce the measurement error and maximize the attenuation of the measurement error, the relative position of the two signals can be adjusted to make the difference of the input sampling system as small as possible, and the sine signal and the step wave signal intersect at the center of the step. At this time, the phases of the two signals are the same, the differential signal is the smallest, and the measurement error is the smallest. For example, Chinese patent CN116087590A discloses a differential sampling control device and method for precise measurement of quantum voltage. The device includes a sampling control unit, a differential sampling unit and a data analysis unit; the sampling control unit is used to receive the zero-phase pulse signal output by the programmable quantum voltage standard, synchronize, delay and multiply the zero-phase pulse signal according to the preset frequency and delay time in the sampling control unit, output a series of sampling trigger signals of preset frequencies, and set the differential sampling unit parameters and control the differential sampling unit to sample; the differential sampling unit is used to continuously trigger the input signal under the sampling trigger signal according to the preset differential sampling unit parameters; the data analysis unit is used to analyze the differential sampling data output by the differential sampling unit, and calculate the phase difference between the quantum step voltage signal and the measured AC sinusoidal voltage signal. However, the measurement error of differential sampling is not only reflected in the difference in phase difference, but also in the sampling parameters of differential sampling itself. When the measurement of AC signals is achieved through different sampling parameters, there will be different degrees of measurement error fluctuations.

[0005] Therefore, how to adjust the sampling parameters of differential sampling to reduce the measurement error is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0006] In view of the defects existing in the above-mentioned prior art, the present invention provides a commutation measurement method and device based on differential sampling, which can reduce the measurement error when measuring AC signals through differential sampling.

[0007] In a first aspect, the present invention provides a commutation measurement method based on differential sampling, which specifically comprises the following steps:

[0008] Based on the initial sampling parameters, the difference between the sinusoidal voltage and the initial AC quantum voltage is sampled in phase change mode to obtain an initial difference voltage;

[0009] Based on the initial difference voltage, the initial AC quantum voltage and the initial sampling parameters are optimized;

[0010] Based on the optimized initial sampling parameters, the difference between the sinusoidal voltage and the optimized initial AC quantum voltage is sampled in phase change mode to obtain the optimized difference voltage;

[0011] Based on the optimized AC quantum voltage and the optimized difference voltage, the amplitude and phase of the sinusoidal voltage are given.

[0012] Further, based on the initial difference voltage, the initial AC quantum voltage and the initial sampling parameters are optimized, specifically including the following steps:

[0013] Based on the convergence setting of the initial difference voltage, the phase of the initial AC quantum voltage is adjusted until the minimum difference voltage is obtained, thereby obtaining the adjusted initial AC quantum voltage;

[0014] Based on the minimum difference voltage, the initial sampling parameters and the initial AC quantum voltage after adjusting the phase are optimized until the minimum measurement error is obtained, and the optimized initial sampling parameters and initial AC quantum voltage are given.

[0015] Furthermore, the measurement error includes at least one of a voltage boost circuit gain error, a differential drive circuit gain error and an acquisition error.

[0016] Further, the initial sampling parameters and the initial AC quantum voltage after the phase adjustment are optimized based on the minimum difference voltage until the minimum measurement error is obtained, and the optimized initial sampling parameters and initial AC quantum voltage are given, which specifically includes the following steps:

[0017] Determine a reference sinusoidal voltage having the same phase as the sinusoidal voltage based on the minimum difference voltage and the initial AC quantum voltage after adjusting the phase;

[0018] Based on the initial AC quantum voltage after phase adjustment and the reference sinusoidal voltage, the initial sampling parameters are analyzed and processed to determine the final sampling parameters;

[0019] Based on the final sampling parameters, the number of steps of the initial AC quantum voltage after the phase adjustment is optimized to determine the final number of steps corresponding to the initial AC quantum voltage after the phase adjustment.

[0020] Furthermore, sampling parameters include sampling rate and sampling window size;

[0021] Based on the initial AC quantum voltage and the reference sinusoidal voltage after phase adjustment, the initial sampling parameters are analyzed and processed to determine the final sampling parameters, which specifically includes the following steps:

[0022] Based on the sampling window size of the initial sampling parameter, the initial AC quantum voltage and the reference sinusoidal voltage after the phase adjustment are sampled in phase switching at different sampling rates to obtain a first error set including multiple overall sampling measurement errors;

[0023] Compare the first error set with the first preset measurement error, provide an overall sampling measurement error that is closest to and smaller than the first preset measurement error, and determine a final sampling rate;

[0024] Based on the determined sampling rate, different sampling window sizes are used to perform phase-commutation sampling on the initial AC quantum voltage and the reference sinusoidal voltage after phase adjustment to determine the final sampling window size.

[0025] Furthermore, the overall sampling measurement error satisfies the following relationship:

[0026]

[0027] In the formula, E r is the overall sampling measurement error, Vs is the reference sinusoidal voltage, V p is the initial AC quantum voltage after phase adjustment, E a is the gain error of the non-inverting terminal of the voltage boost circuit, E b is the inverting terminal gain error of the voltage boost circuit, E d It is the overall gain error of the differential drive circuit and AD acquisition error.

[0028] Further, based on the determined sampling rate, different sampling window sizes are used to perform phase-changing sampling on the initial AC quantum voltage and the reference sinusoidal voltage after phase adjustment to determine the final sampling window size, specifically including the following steps:

[0029] Obtain the total number of sampling points of a single step on the initial AC quantum voltage after adjusting the phase;

[0030] Based on the total number of sampling points obtained, different numbers of sampling points are selected on both sides with the center of the step as the symmetric point to obtain all initial sampling window sizes corresponding to the initial AC quantum voltage after the phase adjustment;

[0031] Based on the determined sampling rate and multiple initial sampling window sizes, the amplitude error of the reference sinusoidal voltage corresponding to the sampling point of each step under each initial sampling window is given;

[0032] The middle step of the analysis corresponds to the standard deviation of the amplitude error, and the deviation threshold is given in combination with the standard deviation;

[0033] By comparing the amplitude error of the reference sinusoidal voltage corresponding to the lower step of each adjacent initial sampling window with the deviation threshold value, the size of each initial sampling window is analyzed to determine the final sampling window size.

[0034] Further, based on the final sampling parameters, the number of steps of the initial AC quantum voltage after the phase adjustment is optimized to determine the final number of steps corresponding to the initial AC quantum voltage after the phase adjustment, including:

[0035] Presetting a plurality of step numbers for the initial AC quantum voltage after the phase adjustment to obtain a plurality of intermediate state AC quantum voltages;

[0036] Based on the final sampling parameters, the intermediate state AC quantum voltage and the reference sinusoidal voltage are sampled in phase conversion to obtain a second error set including a plurality of overall sampling measurement errors;

[0037] The second error set is compared with the second preset measurement error to provide an overall sampling measurement error that is closest to and smaller than the second preset measurement error, and the final number of steps is determined.

[0038] Furthermore, based on the optimized AC quantum voltage and the optimized difference voltage, the amplitude and phase of the sinusoidal voltage are given, including:

[0039] The optimized AC quantum voltage and the optimized difference voltage are superimposed to obtain a reconstructed sinusoidal voltage;

[0040] Performing fast Fourier transform processing on the reconstructed sinusoidal voltage to obtain the amplitude of the reconstructed sinusoidal voltage;

[0041] The phase of the reconstructed sinusoidal voltage is determined based on the phase of the optimized AC quantum voltage.

[0042] In a second aspect, the present invention further provides a commutation measurement device based on differential sampling, which adopts the above-mentioned commutation measurement method based on differential sampling, and specifically includes:

[0043] A sampling module, which is used to perform phase-commutation sampling on the difference between the sinusoidal voltage and the initial AC quantum voltage based on the initial sampling parameters to obtain the initial difference voltage; and to perform phase-commutation sampling on the difference between the sinusoidal voltage and the optimized initial AC quantum voltage based on the optimized initial sampling parameters to obtain the optimized difference voltage;

[0044] An optimization module, which is used to optimize the initial AC quantum voltage and initial sampling parameters based on the initial difference voltage;

[0045] The analysis and processing module is used to provide the amplitude and phase of the sinusoidal voltage based on the optimized AC quantum voltage and the optimized difference voltage.

[0046] Furthermore, the optimization module includes:

[0047] Based on the convergence setting of the initial difference voltage, the phase of the initial AC quantum voltage is adjusted until the minimum difference voltage is obtained, thereby obtaining the adjusted initial AC quantum voltage;

[0048] Based on the minimum difference voltage, the initial sampling parameters and the initial AC quantum voltage after adjusting the phase are optimized until the minimum measurement error is obtained, and the optimized initial sampling parameters and initial AC quantum voltage are given.

[0049] Furthermore, the optimization module includes:

[0050] Determine a reference sinusoidal voltage having the same phase as the sinusoidal voltage based on the minimum difference voltage and the initial AC quantum voltage after adjusting the phase;

[0051] Based on the initial AC quantum voltage after phase adjustment and the reference sinusoidal voltage, the initial sampling parameters are analyzed and processed to determine the final sampling parameters;

[0052] Based on the final sampling parameters, the number of steps of the initial AC quantum voltage after the phase adjustment is optimized to determine the final number of steps corresponding to the initial AC quantum voltage after the phase adjustment.

[0053] Furthermore, the optimization module includes:

[0054] Based on the sampling window size of the initial sampling parameter, the initial AC quantum voltage and the reference sinusoidal voltage after the phase adjustment are sampled in phase switching at different sampling rates to obtain a first error set including multiple overall sampling measurement errors;

[0055] Compare the first error set with the first preset measurement error, provide an overall sampling measurement error that is closest to and smaller than the first preset measurement error, and determine a final sampling rate;

[0056] Based on the determined sampling rate, different sampling window sizes are used to perform phase-commutation sampling on the initial AC quantum voltage and the reference sinusoidal voltage after phase adjustment to determine the final sampling window size.

[0057] Furthermore, the optimization module includes:

[0058] Obtain the total number of sampling points of a single step on the initial AC quantum voltage after adjusting the phase;

[0059] Based on the total number of sampling points obtained, different numbers of sampling points are selected on both sides with the center of the step as the symmetric point to obtain all initial sampling window sizes corresponding to the initial AC quantum voltage after the phase adjustment;

[0060] Based on the determined sampling rate and multiple initial sampling window sizes, the amplitude error of the reference sinusoidal voltage corresponding to the sampling point of each step under each initial sampling window is given;

[0061] The middle step of the analysis corresponds to the standard deviation of the amplitude error, and the deviation threshold is given in combination with the standard deviation;

[0062] By comparing the amplitude error of the reference sinusoidal voltage corresponding to the lower step of each adjacent initial sampling window with the deviation threshold value, the size of each initial sampling window is analyzed to determine the final sampling window size.

[0063] Furthermore, the optimization module also includes:

[0064] Presetting a plurality of step numbers for the initial AC quantum voltage after the phase adjustment to obtain a plurality of intermediate state AC quantum voltages;

[0065] Based on the final sampling parameters, the intermediate state AC quantum voltage and the reference sinusoidal voltage are sampled in phase conversion to obtain a second error set including a plurality of overall sampling measurement errors;

[0066] The second error set is compared with the second preset measurement error to provide an overall sampling measurement error that is closest to and smaller than the second preset measurement error, and the final number of steps is determined.

[0067] Furthermore, the analysis and processing module includes:

[0068] The optimized AC quantum voltage and the optimized difference voltage are superimposed to obtain a reconstructed sinusoidal voltage;

[0069] Performing fast Fourier transform processing on the reconstructed sinusoidal voltage to obtain the amplitude of the reconstructed sinusoidal voltage;

[0070] The phase of the reconstructed sinusoidal voltage is determined based on the phase of the optimized AC quantum voltage.

[0071] The present invention provides a commutation measurement method and device based on differential sampling, which at least have the following beneficial effects:

[0072] (1) Phase switching based on differential sampling can effectively reduce the error caused by channel inconsistency, thereby achieving the effect of reducing measurement error. At the same time, by optimizing and adjusting the sampling parameters of differential sampling, the sinusoidal voltage measurement in the corresponding scenario can be made to further reduce the measurement error.

[0073] (2) By obtaining the minimum differential voltage, the phase of the initial AC quantum voltage can be adjusted to make it the same as the phase of the sinusoidal voltage, which can facilitate the determination of the phase of the sinusoidal voltage and the subsequent solution of the sinusoidal voltage amplitude. In addition, based on the initial AC quantum voltage with adjusted phase, different sampling parameters can be simulated to ultimately determine the optimal sampling parameters that match the current scenario, and ultimately improve the measurement accuracy of the sinusoidal signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] Figure 1 A flow chart of a commutation measurement method based on differential sampling provided by the present invention;

[0075] Figure 2 A flowchart of optimizing initial AC quantum voltage and initial sampling parameters in a certain embodiment of the present invention;

[0076] Figure 3 A flowchart of providing an optimized initial AC quantum voltage and initial sampling parameters for a certain embodiment of the present invention;

[0077] Figure 4 A flowchart of determining final sampling parameters according to an embodiment of the present invention;

[0078] Figure 5 A flowchart of determining a final sampling window size according to an embodiment of the present invention;

[0079] Figure 6 A flowchart of determining the number of steps according to an embodiment of the present invention;

[0080] Figure 7 A schematic diagram of a commutation measurement device based on differential sampling provided by the present invention. DETAILED DESCRIPTION

[0081] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are only 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.

[0082] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings, and "multiple" generally includes at least two.

[0083] It should also be noted that the term "includes", "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, so that a commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprising a ..." do not exclude the existence of other identical elements in the commodity or device including the elements.

[0084] like Figure 1 As shown, the present invention provides a commutation measurement method based on differential sampling, which specifically includes the following steps:

[0085] Based on the initial sampling parameters, the difference between the sinusoidal voltage and the initial AC quantum voltage is sampled in phase change mode to obtain an initial difference voltage;

[0086] Based on the initial difference voltage, the initial AC quantum voltage and the initial sampling parameters are optimized;

[0087] Based on the optimized initial sampling parameters, the difference between the sinusoidal voltage and the optimized initial AC quantum voltage is sampled in phase change mode to obtain the optimized difference voltage;

[0088] Based on the optimized AC quantum voltage and the optimized difference voltage, the amplitude and phase of the sinusoidal voltage are given.

[0089] The initial AC quantum voltage of the present invention can be provided based on a programmable Josephson voltage standard device. Specifically, the programmable Josephson voltage standard device includes a programmable Josephson voltage array chip, a probe, a cryogenic liquid helium device, a bias circuit module, a microwave source, and a rubidium atomic clock. The programmable Josephson voltage array chip is a superconducting device in the programmable Josephson voltage standard device, the cryogenic liquid helium device provides the 4K low temperature environment required for superconductivity for the programmable Josephson voltage array chip, the probe provides a connection port for the chip and the external system, the microwave source provides the chip with a superconducting microwave frequency, the rubidium atomic clock programmable Josephson voltage standard device provides a time reference, and the bias circuit module provides the required control voltage for realizing the signal output of the programmable Josephson voltage array chip. The programmable Josephson array of the programmable Josephson voltage array chip is different from the traditional Josephson array in structure in that the traditional Josephson array is formed by directly connecting a large number of single junctions in series, while the programmable Josephson array is composed of a plurality of sub-arrays containing different Josephson single junctions. The number of Josephson single junctions contained in its subarray is arranged in a binary or ternary sequence, and the bias circuit module can be used to control the bias of the subarrays. Specifically, the bias circuit module provides a bias current of a certain size, controllable direction and stability for each subarray output through the bias circuit, thereby realizing the control of each subarray, thereby realizing the generation of a step AC quantum voltage signal and outputting an AC quantum step wave signal. Therefore, the programmable Josephson voltage standard device can not only output a DC signal with quantum accuracy of different amplitudes as a DC voltage standard, but also synthesize a step-shaped voltage waveform as an AC voltage standard. When the programmable Josephson voltage standard device is used as an AC voltage standard, its output approximates the AC voltage signal through a step-shaped voltage waveform, and its working principle is similar to that of a digital-to-analog converter, but unlike the analog-to-digital converter, the step wave signal output by the programmable Josephson voltage standard device has quantum accuracy when the step is stably output.

[0090] When the differential sampling is performed by the differential sampling system of the present invention, the measurement error mainly includes at least one of the voltage boosting circuit gain error, the differential driving circuit gain error and the AD acquisition error. Among them, the AD acquisition error is the error generated by the analog-to-digital converter (ADC) in the process of converting the analog signal into a digital signal. By adjusting the sampling parameters, the measurement error during differential sampling can be reduced. In addition, when performing differential sampling of the sinusoidal voltage and the initial AC quantum voltage, the sinusoidal voltage and the initial AC quantum voltage are respectively connected to one end of the in-phase input terminal and the inverting input terminal of the voltage boosting circuit; the phase-changing sampling performed by the present invention refers to the differential sampling, on the basis of which the input terminals connected to the sinusoidal voltage and the initial AC quantum voltage are exchanged and then differential sampling is performed, and the average of the two differential sampling results is used as the sampling result of the differential sampling, which can reduce the measurement error caused by the channel. Exemplarily, during phase-changing sampling, the sinusoidal voltage and the initial AC quantum voltage are respectively connected to the in-phase input terminal and the inverting input terminal for differential sampling. After the sampling is completed, the sinusoidal voltage and the initial AC quantum voltage are respectively connected to the inverting input terminal and the in-phase input terminal for differential sampling again to achieve the purpose of phase-changing sampling.

[0091] The present invention performs differential sampling of the sinusoidal voltage and the initial AC quantum voltage through a differential sampling system, which is a conventional structure and will not be described in detail here. The present invention uses a differential sampling system to perform phase-change sampling on the difference between the sinusoidal voltage generated by the AC source and the initial AC quantum voltage generated by the programmable Josephson voltage standard device, and finally reconstructs the measured sinusoidal voltage using the sampling measurement result of the difference signal and the known AC quantum voltage waveform, and then obtains the amplitude of the sinusoidal signal through a fast Fourier transform operation. Since the bias error will not affect the measurement accuracy when the amplitude of the sinusoidal voltage is calculated using a fast Fourier transform, the present invention finally achieves the adjustment and optimization of the sampling parameters and the AC quantum voltage by analyzing the influence of the gain error and the AD sampling error on the measurement result, thereby achieving the effect of reducing the measurement error.

[0092] Among them, Figure 2 As shown, based on the initial difference voltage, the initial AC quantum voltage and the initial sampling parameters are optimized, which may specifically include the following steps:

[0093] Based on the convergence setting of the initial difference voltage, the phase of the initial AC quantum voltage is adjusted until the minimum difference voltage is obtained, thereby obtaining the adjusted initial AC quantum voltage;

[0094] Based on the minimum difference voltage, the initial sampling parameters and the initial AC quantum voltage after adjusting the phase are optimized until the minimum measurement error is obtained, and the optimized initial sampling parameters and initial AC quantum voltage are given.

[0095] like Figure 3 As shown, based on the minimum difference voltage, the initial sampling parameters and the initial AC quantum voltage after adjusting the phase are optimized until the minimum measurement error is obtained, and the optimized initial sampling parameters and initial AC quantum voltage are given, which specifically includes the following steps:

[0096] Determine a reference sinusoidal voltage having the same phase as the sinusoidal voltage based on the minimum difference voltage and the initial AC quantum voltage after adjusting the phase;

[0097] Based on the initial AC quantum voltage after phase adjustment and the reference sinusoidal voltage, the initial sampling parameters are analyzed and processed to determine the final sampling parameters; wherein the sampling parameters may include a sampling rate and a sampling window size;

[0098] Based on the final sampling parameters, the number of steps of the initial AC quantum voltage after the phase adjustment is optimized to determine the final number of steps corresponding to the initial AC quantum voltage after the phase adjustment.

[0099] like Figure 4 As shown, based on the initial AC quantum voltage after phase adjustment and the reference sinusoidal voltage, the initial sampling parameters are analyzed and processed to determine the final sampling parameters, which specifically includes the following steps:

[0100] Based on the sampling window size of the initial sampling parameter, the initial AC quantum voltage and the reference sinusoidal voltage after the phase adjustment are sampled in phase switching at different sampling rates to obtain a first error set including multiple overall sampling measurement errors;

[0101] The first error set is compared with the first preset measurement error to give an overall sampling measurement error that is closest to and smaller than the first preset measurement error, and the final sampling rate is determined; wherein the first preset measurement error is ;

[0102] Based on the determined sampling rate, different sampling window sizes are used to perform phase-commutation sampling on the initial AC quantum voltage and the reference sinusoidal voltage after phase adjustment to determine the final sampling window size.

[0103] When calculating the overall sampling measurement error, the present invention can assume that the sinusoidal voltage signal is V s , the step wave signal (AC quantum voltage signal) is V p , the voltage at the non-inverting end of the differential drive circuit is V + , the reverse terminal voltage is V - , the differential signal is V d The voltage boost circuit non-inverting gain error is E a , the reverse end gain error is E b; Considering the differential drive circuit and AD acquisition error as a whole, the gain error is E d , the AD sampling error changes with the sampling rate, so E d It is also a quantity that changes with the sampling rate. When a sinusoidal voltage is applied to the in-phase terminal and a step wave signal is applied to the reverse terminal, a differential signal V is obtained. d1 When the sinusoidal signal is added to the reverse end and the step wave signal is added to the in-phase end, the differential signal V is obtained. d2 .

[0104]

[0105] The sinusoidal voltage signal V restored by the above two connection methods is s1 、V s2 , indicating that the following relationship is satisfied:

[0106]

[0107] The final calculated sinusoidal voltage signal error E s1 、E s2 , as shown in Figure 2, satisfies the following relationship:

[0108]

[0109]

[0110] Since the main source of error is the mismatch of resistor values, which leads to gain error, VISHAY 0.01% resistors are used in the circuit, so the channel error is maintained at 10 -4 Magnitude, E a E b The product of the two errors is less than 10 -7 Therefore, the influence of this item on the final error can be ignored; E d The coefficient before is The difference between the sine signal and the step wave signal is small, and the influence of this part on the error is also relatively small. Therefore, the main factor affecting the final measurement error is the gain error difference between the two channels. Due to the device itself, this part of the error must exist and it is difficult to make it very low. In order to reduce the influence of channel error, the present invention adopts a phase-changing measurement method, and the average value of the two measurement results after phase-changing is taken as the measurement result. According to V d1 and V d2 The relative error E after commutation can be obtained r , that is, the overall sampling measurement error, which satisfies the following relationship:

[0111]

[0112] In the formula, Er is the overall sampling measurement error, Vs is the reference sinusoidal voltage, V p is the initial AC quantum voltage after phase adjustment, E a is the gain error of the non-inverting terminal of the voltage boost circuit, E b is the inverting terminal gain error of the voltage boost circuit, E d It is the overall gain error of the differential drive circuit and AD acquisition error.

[0113] The main factor affecting the differential measurement based on quantum technology is the step wave transition process. The main source of the transition process is the influence of the programmable Josephson voltage standard device’s own settling time, which is , the bandwidth limitation of the voltage boosting circuit, whose bandwidth is 1.2 MHz, the filtering effect of the coupled filter circuit in the differential sampling system, the signal cutoff frequency of the filter circuit is 330 kHz, and the filtering effect of the RC equivalent circuit inside the ADC, wherein the RC filter circuit before the ADC and the internal filter of the ADC constitute a second-order filter. The spectrum of the restored sinusoidal signal is the harmonic component of the differential signal filtered out after passing through the filter circuit, that is, the harmonic component after the step wave is filtered out, and the transition process of the step wave is composed of the remaining harmonic components after being filtered out by the filter. Therefore, in the actual measurement process, step scanning point measurement should be performed according to the measured signal. Based on this, the present invention needs to select the sampling window size after determining the sampling rate through the overall sampling measurement error. Among them, if Figure 5 As shown, based on the determined sampling rate, different sampling window sizes are used to perform phase-changing sampling on the initial AC quantum voltage and the reference sinusoidal voltage after phase adjustment to determine the final sampling window size, specifically including the following steps:

[0114] Obtain the total number of sampling points of a single step on the initial AC quantum voltage after adjusting the phase;

[0115] Based on the total number of sampling points obtained, different numbers of sampling points are selected on both sides with the center of the step as the symmetric point to obtain all initial sampling window sizes corresponding to the initial AC quantum voltage after the phase adjustment;

[0116] Based on the determined sampling rate and multiple initial sampling window sizes, the amplitude error of the reference sinusoidal voltage corresponding to the sampling point of each step under each initial sampling window is given;

[0117] The middle step of the analysis corresponds to the standard deviation of the amplitude error, and the deviation threshold is given in combination with the standard deviation; the deviation threshold is three times the standard deviation;

[0118] By comparing the amplitude error of the reference sinusoidal voltage corresponding to the lower step of each adjacent initial sampling window with the deviation threshold value, the size of each initial sampling window is analyzed to determine the final sampling window size.

[0119] In actual scenarios, when the sampling window size is 100%, the transition process is included, which makes the amplitude error of the sinusoidal signal relatively large. Therefore, the influence of the transition process should be avoided in the actual measurement process; when the transition process is not included, although the attenuation coefficient is large when the sampling window is small, it cannot be reflected due to the influence of Class A uncertainty (uncertainty evaluated by statistical methods). Preferably, the sampling window size is 60% of the number of sampling points in the middle of the step.

[0120] In addition, the influence of channel error on the measurement result of sinusoidal voltage signal can be reduced by phase-changing sampling measurement; and as the number of steps increases, E r However, in the actual measurement process, due to the reasons of the programmable Josephson voltage standard device itself, there will be a transition process in the step wave signal, and the time constant of the transition process is a constant. When the number of steps increases, the proportion of sampling points affected by the transition process to the total sampling points of the step will increase, resulting in a decrease in the number of points that can be used for calculation, and its Class A measurement uncertainty will increase accordingly, which in turn affects the final measurement uncertainty. Therefore, in actual measurement, the appropriate number of steps must be selected according to the actual situation.

[0121] Specifically, Figure 6 As shown, based on the final sampling parameters, the number of steps of the initial AC quantum voltage after the phase is adjusted is optimized, and the final number of steps corresponding to the initial AC quantum voltage after the phase is adjusted is determined, including:

[0122] Presetting a plurality of step numbers for the initial AC quantum voltage after the phase adjustment to obtain a plurality of intermediate state AC quantum voltages;

[0123] Based on the final sampling parameters, the intermediate state AC quantum voltage and the reference sinusoidal voltage are sampled in phase conversion to obtain a second error set including a plurality of overall sampling measurement errors;

[0124] The second error set is compared with the second preset measurement error to give the overall sampling measurement error that is closest to and smaller than the second preset measurement error, and the final number of steps is determined. The second preset measurement error is .

[0125] Based on the optimized AC quantum voltage and the optimized difference voltage, the amplitude and phase of the sinusoidal voltage are given, including:

[0126] The optimized AC quantum voltage and the optimized difference voltage are superimposed to obtain a reconstructed sinusoidal voltage;

[0127] Performing fast Fourier transform processing on the reconstructed sinusoidal voltage to obtain the amplitude of the reconstructed sinusoidal voltage;

[0128] Based on the phase of the optimized AC quantum voltage, the phase of the reconstructed sinusoidal voltage is determined, wherein the phase of the optimized AC quantum voltage is the same as the phase of the reconstructed sinusoidal voltage.

[0129] like Figure 7 As shown, the present invention also provides a commutation measurement device based on differential sampling, which adopts the above-mentioned commutation measurement method based on differential sampling, specifically comprising:

[0130] A sampling module, which is used to perform phase-commutation sampling on the difference between the sinusoidal voltage and the initial AC quantum voltage based on the initial sampling parameters to obtain the initial difference voltage; and to perform phase-commutation sampling on the difference between the sinusoidal voltage and the optimized initial AC quantum voltage based on the optimized initial sampling parameters to obtain the optimized difference voltage;

[0131] An optimization module, which is used to optimize the initial AC quantum voltage and initial sampling parameters based on the initial difference voltage;

[0132] The analysis and processing module is used to provide the amplitude and phase of the sinusoidal voltage based on the optimized AC quantum voltage and the optimized difference voltage.

[0133] Furthermore, the optimization module includes:

[0134] Based on the convergence setting of the initial difference voltage, the phase of the initial AC quantum voltage is adjusted until the minimum difference voltage is obtained, thereby obtaining the adjusted initial AC quantum voltage;

[0135] Based on the minimum difference voltage, the initial sampling parameters and the initial AC quantum voltage after adjusting the phase are optimized until the minimum measurement error is obtained, and the optimized initial sampling parameters and initial AC quantum voltage are given.

[0136] Furthermore, the optimization module includes:

[0137] Determine a reference sinusoidal voltage having the same phase as the sinusoidal voltage based on the minimum difference voltage and the initial AC quantum voltage after adjusting the phase;

[0138] Based on the initial AC quantum voltage after phase adjustment and the reference sinusoidal voltage, the initial sampling parameters are analyzed and processed to determine the final sampling parameters;

[0139] Based on the final sampling parameters, the number of steps of the initial AC quantum voltage after the phase adjustment is optimized to determine the final number of steps corresponding to the initial AC quantum voltage after the phase adjustment.

[0140] Furthermore, the optimization module includes:

[0141] Based on the sampling window size of the initial sampling parameter, the initial AC quantum voltage and the reference sinusoidal voltage after the phase adjustment are sampled in phase switching at different sampling rates to obtain a first error set including multiple overall sampling measurement errors;

[0142] Compare the first error set with the first preset measurement error, provide an overall sampling measurement error that is closest to and smaller than the first preset measurement error, and determine a final sampling rate;

[0143] Based on the determined sampling rate, different sampling window sizes are used to perform phase-commutation sampling on the initial AC quantum voltage and the reference sinusoidal voltage after phase adjustment to determine the final sampling window size.

[0144] Furthermore, the optimization module includes:

[0145] Obtain the total number of sampling points of a single step on the initial AC quantum voltage after adjusting the phase;

[0146] Based on the total number of sampling points obtained, different numbers of sampling points are selected on both sides with the center of the step as the symmetric point to obtain all initial sampling window sizes corresponding to the initial AC quantum voltage after the phase adjustment;

[0147] Based on the determined sampling rate and multiple initial sampling window sizes, the amplitude error of the reference sinusoidal voltage corresponding to the sampling point of each step under each initial sampling window is given;

[0148] The middle step of the analysis corresponds to the standard deviation of the amplitude error, and the deviation threshold is given in combination with the standard deviation;

[0149] By comparing the amplitude error of the reference sinusoidal voltage corresponding to the lower step of each adjacent initial sampling window with the deviation threshold value, the size of each initial sampling window is analyzed to determine the final sampling window size.

[0150] Furthermore, the optimization module also includes:

[0151] Presetting a plurality of step numbers for the initial AC quantum voltage after the phase adjustment to obtain a plurality of intermediate state AC quantum voltages;

[0152] Based on the final sampling parameters, the intermediate state AC quantum voltage and the reference sinusoidal voltage are sampled in phase conversion to obtain a second error set including a plurality of overall sampling measurement errors;

[0153] The second error set is compared with the second preset measurement error to provide an overall sampling measurement error that is closest to and smaller than the second preset measurement error, and the final number of steps is determined.

[0154] Furthermore, the analysis and processing module includes:

[0155] The optimized AC quantum voltage and the optimized difference voltage are superimposed to obtain a reconstructed sinusoidal voltage;

[0156] Performing fast Fourier transform processing on the reconstructed sinusoidal voltage to obtain the amplitude of the reconstructed sinusoidal voltage;

[0157] The phase of the reconstructed sinusoidal voltage is determined based on the phase of the optimized AC quantum voltage.

[0158] Although preferred embodiments of the present invention have been described, additional changes and modifications may be made to these embodiments by those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A commutation measurement method based on differential sampling, characterized in that: The specific steps include: Based on the initial sampling parameters, the difference between the sinusoidal voltage and the initial AC quantum voltage is sampled in phase change mode to obtain an initial difference voltage; Based on the initial difference voltage, the initial AC quantum voltage and the initial sampling parameters are optimized, specifically including the following steps: Based on the convergence setting of the initial difference voltage, the phase of the initial AC quantum voltage is adjusted until the minimum difference voltage is obtained, and the initial AC quantum voltage after the phase is adjusted is obtained; based on the minimum difference voltage, the initial sampling parameters and the initial AC quantum voltage after the phase is adjusted are optimized until the minimum measurement error is obtained, and the optimized initial sampling parameters and the optimized initial AC quantum voltage are given; Based on the optimized initial sampling parameters, the difference between the sinusoidal voltage and the optimized initial AC quantum voltage is sampled in phase change mode to obtain the optimized difference voltage; Based on the optimized initial AC quantum voltage and the optimized difference voltage, the amplitude and phase of the sinusoidal voltage are given; Based on the minimum difference voltage, the initial sampling parameters and the initial AC quantum voltage after adjusting the phase are optimized until the minimum measurement error is obtained, and the optimized initial sampling parameters and the optimized initial AC quantum voltage are given, which specifically includes the following steps: Determine a reference sinusoidal voltage having the same phase as the sinusoidal voltage based on the minimum difference voltage and the initial AC quantum voltage after adjusting the phase; Based on the initial AC quantum voltage after phase adjustment and the reference sinusoidal voltage, the initial sampling parameters are analyzed and processed to determine the final sampling parameters; Based on the final sampling parameters, the number of steps of the initial AC quantum voltage after the phase adjustment is optimized to determine the final number of steps corresponding to the initial AC quantum voltage after the phase adjustment, including: Preset multiple step numbers for the initial AC quantum voltage after phase adjustment to obtain multiple intermediate AC quantum voltages; perform phase switching sampling on the intermediate AC quantum voltage and the reference sinusoidal voltage based on the final sampling parameters to obtain a second error set including multiple overall sampling measurement errors; compare the second error set with the second preset measurement error to provide an overall sampling measurement error that is closest to and less than the second preset measurement error, and determine the final number of steps; Among them, the sampling parameters include sampling rate and sampling window size; Based on the initial AC quantum voltage and the reference sinusoidal voltage after phase adjustment, the initial sampling parameters are analyzed and processed to determine the final sampling parameters, which specifically includes the following steps: Based on the sampling window size of the initial sampling parameter, the initial AC quantum voltage after the phase adjustment and the reference sinusoidal voltage are sampled in phase switching at different sampling rates to obtain a first error set including multiple overall sampling measurement errors; the first error set is compared with the first preset measurement error to give an overall sampling measurement error that is closest to and smaller than the first preset measurement error, and a final sampling rate is determined; based on the determined sampling rate, the initial AC quantum voltage after the phase adjustment and the reference sinusoidal voltage are sampled in phase switching at different sampling window sizes to determine a final sampling window size; The overall sampling measurement error satisfies the following relationship: ; In the formula, E r is the overall sampling measurement error, Vs is the reference sinusoidal voltage, V p is the initial AC quantum voltage after phase adjustment, E a is the gain error of the non-inverting terminal of the voltage boost circuit, E b is the inverting terminal gain error of the voltage boost circuit, E d It is the overall gain error of the differential drive circuit and AD acquisition error.

2. The commutation measurement method based on differential sampling as claimed in claim 1, characterized in that: The measurement error includes at least one of a voltage boost circuit gain error, a differential drive circuit gain error and an AD acquisition error.

3. The commutation measurement method based on differential sampling as claimed in claim 1, characterized in that: Based on the determined sampling rate, the initial AC quantum voltage and the reference sinusoidal voltage after phase adjustment are sampled in phase switching through different sampling window sizes to determine the final sampling window size, which specifically includes the following steps: Obtain the total number of sampling points of a single step on the initial AC quantum voltage after adjusting the phase; Based on the total number of sampling points obtained, different numbers of sampling points are selected on both sides with the center of the step as the symmetric point to obtain all initial sampling window sizes corresponding to the initial AC quantum voltage after the phase adjustment; Based on the determined sampling rate and multiple initial sampling window sizes, the amplitude error of the reference sinusoidal voltage corresponding to the sampling point of each step under each initial sampling window is given; The middle step of the analysis corresponds to the standard deviation of the amplitude error, and the deviation threshold is given in combination with the standard deviation; By comparing the amplitude error of the reference sinusoidal voltage corresponding to the lower step of each adjacent initial sampling window with the deviation threshold value, the size of each initial sampling window is analyzed to determine the final sampling window size.

4. The commutation measurement method based on differential sampling as claimed in claim 1, characterized in that: Based on the optimized initial AC quantum voltage and the optimized difference voltage, the amplitude and phase of the sinusoidal voltage are given, including: The optimized initial AC quantum voltage and the optimized difference voltage are superimposed to obtain a reconstructed sinusoidal voltage; Performing fast Fourier transform processing on the reconstructed sinusoidal voltage to obtain the amplitude of the reconstructed sinusoidal voltage; The phase of the reconstructed sinusoidal voltage is determined based on the optimized phase of the initial AC quantum voltage.

5. A commutation measurement device based on differential sampling, characterized in that: The commutation measurement method based on differential sampling as claimed in any one of claims 1 to 4 is adopted, specifically comprising: A sampling module, which is used to perform phase-commutation sampling on the difference between the sinusoidal voltage and the initial AC quantum voltage based on the initial sampling parameters to obtain the initial difference voltage; and to perform phase-commutation sampling on the difference between the sinusoidal voltage and the optimized initial AC quantum voltage based on the optimized initial sampling parameters to obtain the optimized difference voltage; An optimization module, which is used to optimize the initial AC quantum voltage and initial sampling parameters based on the initial difference voltage; The analysis and processing module is used to provide the amplitude and phase of the sinusoidal voltage based on the optimized initial AC quantum voltage and the optimized difference voltage.

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