CN101988957B - Dynamic detection method and system of sampling accuracy of electric quantity of merging unit of substation - Google Patents

Abstract

The invention discloses a dynamic detection method and system for the accuracy of electricity sampling of a substation merging unit. The system includes a standard detection device, a measurement data comparison module, an error interval acquisition module, and a detection result discrimination module. The standard detection device is used to measure the power at the same time point as the merging unit; the measurement data comparison module is used to compare the measurement data at the same time point to obtain the measurement errors of N time points; the error interval acquisition module In order to obtain the interval interval 2*a of the measurement error; the detection result discrimination module is used to judge whether the interval 2*a of the above-mentioned measurement error interval is within the range corresponding to the interval of the measurement level set by the merging unit; if so, it is considered that the The merged unit meets its grade requirements, otherwise it is considered that the merged unit does not meet its grade requirements. The invention can dynamically detect the accuracy of electric quantity sampling of the merging unit, and fills up the gap in this technical field.

Description

Dynamic detection method and system for power sampling accuracy of substation merging unit

technical field

The present invention relates to a dynamic detection method for the accuracy of electric quantity sampling, in particular to a dynamic detection method for the accuracy of electric quantity sampling of a digital substation merging unit; in addition, the present invention also relates to a dynamic detection method for the accuracy of electric quantity sampling of a digital substation merging unit system.

Background technique

The traditional way to detect the accuracy of power sampling of the merged unit of the digital substation, such as the detection method of the remote AC sampling device, AC transmitter and remote measurement equipment RTU, is based on the transient measurement and uses the direct comparison method for measurement . That is to say, this measurement method is based on the fact that the measured system is in a relatively stable state and the signal fluctuation is small. The values measured by the tested device and the standard testing device will not change greatly within a certain period of time, and the two are compared to obtain the steady-state measurement error. At the same time, when the measured signal changes greatly, the gross error caused by the sampling time deviation between the detected device and the detection device will be artificially eliminated. This detection method is not suitable for dynamic detection.

For the digital substation merging unit, it is required to sample 80 points per cycle during measurement, and the sampled values transmitted each time must meet the requirements of measurement accuracy. In view of this feature, the standard detection device as a detection merging unit must meet or even exceed the relevant technical requirements of the detected device. The measurement error is no longer the total error of a device, but must reflect the measurement error of each point of the merging unit within a period of time, and the distribution of the measurement error. Even if the power signal of the operating system fluctuates within a certain range or the system oscillates, every point of measurement error transmitted by the merging unit must meet the measurement accuracy requirements.

Contents of the invention

The technical problem to be solved by the present invention is to provide a dynamic detection method for the accuracy of electric quantity sampling of the merging unit of the digital substation, which can dynamically detect the accuracy of the electric quantity sampling of the merging unit of the digital substation.

In addition, the present invention also provides a dynamic detection system for the accuracy of electricity sampling of the merging unit of the digital substation.

In order to solve the problems of the technologies described above, the present invention adopts the following technical solutions:

A method for dynamically detecting the accuracy of power sampling of a digital substation merging unit, characterized in that the method includes the following steps:

A. A standard detection device is provided, and the merging unit and the standard detection device measure the electric quantity respectively at the same time point;

B. Compare the measurement data at the same time point, and obtain the measurement errors e ₁ , e ₂ , e ₃ ,..., e _N of N time points;

C. Obtain the measurement error interval interval 2*a;

Among them, a=kσ, standard deviation $\mathrm{\σ}=\sqrt{\frac{1}{N-1}\underset{\mathrm{no}=1}{\overset{N}{\mathrm{\Σ}}}{(e_{\mathrm{no}}-\stackrel{\‾}{e})}^2},$ k is the setting coefficient;

$\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; e</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; N</span>}}\underset{\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{\mathrm{<span\; class="notranslate">\; N</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; e</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; N</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; e</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; e</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; e</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; e</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ;</span>$

D. Judging whether the interval 2*a of the above-mentioned measurement error interval is within the range corresponding to the measurement level set by the merging unit; if so, it is considered that the merging unit meets its level requirements, otherwise it is considered that the merging unit does not meet its level requirements.

As a preferred solution of the present invention, the measurement error interval is [e-a, e+a].

As a preferred solution of the present invention, in step A, a time calibration unit is used to calibrate the merging unit of the digital substation, so that the measurement results of the merging unit and the standard detection device are at the same time point. Preferably, the time calibration unit is a synchronous clock high precision time calibration unit.

As a preferred solution of the present invention, in step C, k is greater than or equal to 1 and less than or equal to 5. Preferably, in step C, k=3.

A method for dynamically detecting the accuracy of electric quantity sampling of a digital substation merging unit, the method comprising the following steps:

A. A standard detection device is provided, and the merging unit and the standard detection device measure the electric quantity respectively at the same time point;

B. Compare the measurement data at the same time point, and obtain the measurement errors e ₁ , e ₂ , e ₃ ,..., e _N of N time points;

C. Find the measurement error interval [e-a, e+a], and obtain the interval 2*a of the measurement error interval;

in, $\stackrel{\&OverBar;}{e}=\frac{1}{N}\underset{\mathrm{no}=1}{\overset{N}{\mathrm{\&Sigma;}}}{e}_{\mathrm{no}}=\frac{1}{N}(e_1+e_2+...+e_{\mathrm{no}}+...+e_N),$ a=kσ, standard deviation $\mathrm{\&sigma;}=\sqrt{\frac{1}{N-1}\underset{\mathrm{no}=1}{\overset{N}{\mathrm{\&Sigma;}}}{(e_{\mathrm{no}}-\stackrel{\&OverBar;}{e})}^2},$ k is the setting coefficient;

D. Judging whether the interval 2*a of the above-mentioned measurement error interval is within the range corresponding to the measurement level set by the merging unit; if so, it is considered that the merging unit meets its level requirements, otherwise it is considered that the merging unit does not meet its level requirements.

A dynamic detection system for the accuracy of electricity sampling of a digital substation merging unit, the system includes a standard detection device, a measurement data comparison module, an error interval acquisition module, and a detection result discrimination module.

The standard detection device is used to measure the power at the same time point as the merging unit;

The measurement data comparison module is used to compare the measurement data at the same time point, and obtain the measurement errors e ₁ , e ₂ , e ₃ ,..., e _N of N time points;

The error interval interval acquisition module is used to obtain the interval interval 2*a of the measurement error; wherein, a=kσ, standard deviation $\mathrm{\&sigma;}=\sqrt{\frac{1}{N-1}\underset{\mathrm{no}=1}{\overset{N}{\mathrm{\&Sigma;}}}{(e_{\mathrm{no}}-\stackrel{\&OverBar;}{e})}^2},$ $\stackrel{\&OverBar;}{e}=\frac{1}{N}\underset{\mathrm{no}=1}{\overset{N}{\mathrm{\&Sigma;}}}{e}_{\mathrm{no}}=\frac{1}{N}(e_1+e_2+...+e_{\mathrm{no}}+...+e_N),$ k is the setting coefficient;

The detection result discrimination module is used to judge whether the interval 2*a of the above-mentioned measurement error interval is within the range corresponding to the measurement level set by the merging unit; if so, it is considered that the merging unit meets its level requirements; its level requirements.

As a preferred solution of the present invention, the measurement error interval is [e-a, e+a].

As a preferred solution of the present invention, the system further includes a synchronous clock high-precision time calibration unit, which is used to calibrate the digital substation merging unit, so that the measurement results of the merging unit and the standard detection device are at the same time point.

The beneficial effect of the present invention is that: the method and system for dynamically detecting the accuracy of electricity sampling of the merging unit of the digital substation proposed by the present invention can dynamically detect the accuracy of the electricity sampling of the merging unit, filling the gap in this technical field.

Description of drawings

Fig. 1 is a schematic diagram of the composition of the dynamic detection system of the present invention.

Fig. 2 is a flow chart of the dynamic detection method of the present invention.

Detailed ways

Preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

Embodiment one

The invention discloses a dynamic detection system for the accuracy of electric quantity sampling of a digital substation merging unit. The system can dynamically detect the accuracy of electric quantity sampling of a digital substation merging unit.

Referring to FIG. 1 , the dynamic detection system 100 of the present invention includes a standard detection device 10 , a measurement data comparison module 20 , an error interval acquisition module 30 , and a detection result judgment module 40 .

The standard detection device 10 is used to measure the electricity respectively at the same time point as the merging unit 60 . Since the detection reference object (the operating environment of the power system during detection) is changing, the system can also include a time calibration unit to calibrate the digital substation merging unit to ensure that the measurement results of the merging unit and the standard detection device are all at the same time point superior. The time calibration unit may be a synchronous clock high precision time calibration unit 50 .

The measurement data comparing module 20 is used to compare the measurement data at the same time point, and obtain measurement errors e ₁ , e ₂ , e ₃ , . . . , e _N of N time points.

The error interval acquisition module 30 is used to calculate the measurement error interval [ea, e+a], and obtain the interval 2*a of the measurement error. Among them, a=kσ, standard deviation $\mathrm{\&sigma;}=\sqrt{\frac{1}{N-1}\underset{\mathrm{no}=1}{\overset{N}{\mathrm{\&Sigma;}}}{(e_{\mathrm{no}}-\stackrel{\&OverBar;}{e})}^2},$ Average error of each error $\stackrel{\&OverBar;}{e}=\frac{1}{N}\underset{\mathrm{no}=1}{\overset{N}{\mathrm{\&Sigma;}}}{e}_{\mathrm{no}}=\frac{1}{N}(e_1+e_2+...+e_{\mathrm{no}}+...+e_N),$ k is the setting coefficient. For example, k can be greater than or equal to 1 and less than or equal to 5. Preferably, the value of k is 3. According to the normal distribution density table, at this time, 99.73% of the measurement errors appear in the interval [e-3σ, e+3σ].

The detection result discriminating module 40 is used for judging whether the interval 2*a of the above-mentioned measurement error interval is within the scope of the corresponding interval of the measurement level set by the merging unit 60; Unit does not meet its class requirements. The values required by the measurement level are known values and can be obtained according to the corresponding measurement level.

The composition of the dynamic detection system for the accuracy of electric quantity sampling of the merging unit of the digital substation of the present invention has been introduced above, and the dynamic detection method of the present invention will be introduced below in conjunction with FIG. 2 . Referring to Figure 2, the dynamic detection method includes the following steps:

A. A standard detection device is provided, and the merging unit and the standard detection device respectively measure the electric quantity at the same time point. Since the detection reference object (the operating environment of the power system during detection) is changing, the system can also include a synchronous clock high-precision time calibration unit 50 to calibrate the digital substation merging unit to ensure that the measurement results of the merging unit and the standard detection device are consistent. at the same point in time.

B. Comparing the measurement data at the same time point to obtain measurement errors e ₁ , e ₂ , e ₃ , . . . , e _N of N time points.

C. Calculate the measurement error interval [e-a, e+a], and obtain the interval 2*a of the measurement error interval.

in, $\stackrel{\&OverBar;}{e}=\frac{1}{N}\underset{\mathrm{no}=1}{\overset{N}{\mathrm{\&Sigma;}}}{e}_{\mathrm{no}}=\frac{1}{N}(e_1+e_2+...+e_{\mathrm{no}}+...+e_N),$ a=kσ, standard deviation $\mathrm{\&sigma;}=\sqrt{\frac{1}{N-1}\underset{\mathrm{no}=1}{\overset{N}{\mathrm{\&Sigma;}}}{(e_{\mathrm{no}}-\stackrel{\&OverBar;}{e})}^2},$ k is the setting coefficient. For example, k can be greater than or equal to 1 and less than or equal to 5. Preferably, the value of k is 3. According to the normal distribution density table, at this time, 99.73% of the measurement errors appear in the interval [e-3σ, e+3σ].

D. Judging whether the interval 2*a of the above-mentioned measurement error interval is within the range corresponding to the measurement level set by the merging unit; if so, it is considered that the merging unit meets its level requirements, otherwise it is considered that the merging unit does not meet its level requirements.

To sum up, the dynamic detection method for the accuracy of electric quantity sampling of the merging unit of the digital substation proposed by the present invention can dynamically detect the accuracy of the electric quantity sampling of the merging unit, filling the gap in this technical field.

Embodiment two

The difference between this embodiment and Embodiment 1 is that in this embodiment, there is no need to obtain the measurement error interval, and in step C, it is only necessary to obtain the measurement error interval interval 2*a.

The dynamic detection method for the accuracy of electric quantity sampling of the merging unit of the digital substation of the present invention comprises the following steps:

A. A standard detection device is provided, and the merging unit and the standard detection device measure the electric quantity respectively at the same time point;

B. Compare the measurement data at the same time point, and obtain the measurement errors e ₁ , e ₂ , e ₃ ,..., e _N of N time points;

C. Obtain the measurement error interval interval 2*a;

Among them, a=kσ, standard deviation $\mathrm{\&sigma;}=\sqrt{\frac{1}{N-1}\underset{\mathrm{no}=1}{\overset{N}{\mathrm{\&Sigma;}}}{(e_{\mathrm{no}}-\stackrel{\&OverBar;}{e})}^2},$ k is the setting coefficient; $\stackrel{\&OverBar;}{e}=\frac{1}{N}\underset{\mathrm{no}=1}{\overset{N}{\mathrm{\&Sigma;}}}{e}_{\mathrm{no}}=\frac{1}{N}(e_1+e_2+...+e_{\mathrm{no}}+...+e_N);$

D. If the interval 2*a of the above-mentioned measurement error interval is within the range corresponding to the measurement level set by the merging unit, then the merging unit is considered to meet its level requirements; otherwise, the merging unit is considered not to meet its level requirements.

Embodiment Three

This embodiment introduces the working principle of the present invention.

Since the detection reference object (the operating environment of the power system during detection) is changing, in this embodiment, the digital substation merging unit ensures that the measurement results of the merging unit and the standard detection device are at the same time point through high-precision time calibration , and then compare the data at the same time point. Due to the difference in measuring equipment, there will still be a certain deviation in the two sets of sampling results, which is the measurement error e. However, the measurement error at each measurement time point is not exactly the same, and the size of this measurement error changes randomly, and the real measurement error μ _e is unknown.

How to analyze the measurement accuracy of the detected merging unit: After a large number of measurements, it is found that the distribution of this measurement error still follows the normal distribution law. Through statistical methods, in a series of N times of equal precision measurement, N measurement errors e ₁ , e ₂ , e ₃ ,..., e _n ,..., e _N can be obtained, and the real measurement error μ _e The best estimate made is the arithmetic mean of the e _n :

$\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; e</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; N</span>}}\underset{\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{\mathrm{<span\; class="notranslate">\; N</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; e</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; N</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; e</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; e</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; e</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; e</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}}<span\; class="notranslate">\; )</span>$

It should be noted that when the number of measurements N is infinite, e will converge to the real measurement error μ _e according to the probability.

The average error e represents the real measurement error of the merging unit, but due to the dynamic measurement characteristics of the merging unit, e cannot yet reflect the error distribution of the merging unit during the dynamic measurement process. Comparing each measurement error with the real measurement error μe will produce a certain deviation. According to the characteristics of normal distribution, the dispersion of measurement error can be calculated by calculating its standard deviation σ. This is the so-called Bessel formula:

$\mathrm{<span\; class="notranslate">\; \&sigma;</span>}<span\; class="notranslate">\; =</span>\sqrt{\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}\underset{\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{\mathrm{<span\; class="notranslate">\; N</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; e</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; -</span>\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; e</span>}}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}$

The value of the standard deviation σ is not a specific error, and its size represents the degree of dispersion of various measurement errors. The smaller the value of σ, the sharper the normal distribution curve. This means that measurement errors with smaller deviations are more likely to occur, while measurement errors with larger deviations are less likely to occur.

Since there are relatively strict technical requirements for high-speed and accurate testing of the merging unit, the evaluation of its measurement accuracy is not as simple as the average error e, and the standard deviation σ of the measurement error represents the requirement for the discreteness of the measurement error. According to the principle of the normal distribution curve, it can be known that the probability of the detected error e appearing in the interval [e-a, e+a] is closely related to the size of the standard deviation σ, so the interval limit is often taken as several times of σ, that is a=kσ, the value of domestic statistical routine is 3σ. It can be seen from the normal distribution density table that 99.73% of the measurement errors occur within the interval [e-3σ, e+3σ].

The value interval of the measurement error represents the range with a higher probability of occurrence of the measurement error, and the smaller the interval, the smaller the dispersion of the measurement results. If the interval range of this interval is within the scope of the combined unit measurement level, the detection device is considered to meet its level requirements. For the standard deviation σ of the measurement error, there is no clear regulation in the existing detection standards, which needs to be formulated in the future for the detection standards of substation merged units.

The description and application of the invention herein is illustrative and is not intended to limit the scope of the invention to the above-described embodiments. Variations and changes to the embodiments disclosed herein are possible, and substitutions and equivalents for various components of the embodiments are known to those of ordinary skill in the art. It should be clear to those skilled in the art that the present invention can be realized in other forms, structures, arrangements, proportions, and with other components, materials and components without departing from the spirit or essential characteristics of the present invention. Other modifications and changes may be made to the embodiments disclosed herein without departing from the scope and spirit of the invention.

Claims (9)

1. a dynamic detection method of substation merging unit electric quantity sampling accuracy, it is characterized in that, the method comprises the steps: A. A standard detection device is provided, and the merging unit and the standard detection device measure the electric quantity respectively at the same time point; B. Compare the measurement data at the same time point, and obtain the measurement errors e ₁ , e ₂ , e ₃ ,..., e _N of N time points; C. Obtain the measurement error interval interval 2*a; Among them, a=kσ, standard deviation k is the setting coefficient; $\stackrel{\&OverBar;}{e}=\frac{1}{N}\underset{\mathrm{no}=1}{\overset{N}{\mathrm{\&Sigma;}}}{e}_{\mathrm{no}}=\frac{1}{N}(e_1+e_2+\&CenterDot;\&CenterDot;\&CenterDot;+e_{\mathrm{no}}+\&Center\; Dot;\&Center\; Dot;\&Center\; Dot;+e_N);$ D. Judging whether the interval 2*a of the above-mentioned measurement error interval is within the range corresponding to the measurement level set by the merging unit; if so, it is considered that the merging unit meets its level requirements, otherwise it is considered that the merging unit does not meet its level requirements. 2. the dynamic detection method of substation merging unit electric quantity sampling accuracy according to claim 1, is characterized in that: The measurement error interval is 3. the dynamic detection method of substation merging unit electric quantity sampling accuracy according to claim 1, is characterized in that: In step A, a time calibration unit is used to calibrate the merging unit of the digital substation, so that the measurement results of the merging unit and the standard detection device are at the same time point. 4. the dynamic detection method of the substation merging unit electric quantity sampling accuracy according to claim 3, is characterized in that: The time calibration unit is a synchronous clock high precision time calibration unit. 5. the dynamic detection method of the sampling accuracy of substation merging unit electric quantity according to claim 1, is characterized in that: In step C, k is greater than or equal to 1 and less than or equal to 5. 6. the dynamic detection method of the sampling accuracy of substation merging unit electric quantity according to claim 5, is characterized in that: In Step C, k=3. 7. A dynamic detection system for the accuracy of power sampling of substation merging units, characterized in that the system includes: The standard detection device is used to measure the power at the same time point as the merging unit; The measurement data comparison module is used to compare the measurement data at the same time point, and obtain the measurement errors e ₁ , e ₂ , e ₃ ,..., e _N of N time points; The error interval interval acquisition module is used to obtain the interval interval 2*a of the measurement error; wherein, a=kσ, standard deviation $\mathrm{\&sigma;}=\sqrt{\frac{1}{N-1}\underset{\mathrm{no}=1}{\overset{N}{\mathrm{\&Sigma;}}}{(e_{\mathrm{no}}-\stackrel{\&OverBar;}{e})}^2},$ $\stackrel{\&OverBar;}{e}=\frac{1}{N}\underset{\mathrm{no}=1}{\overset{N}{\mathrm{\&Sigma;}}}{e}_{\mathrm{no}}=\frac{1}{N}(e_1+e_2+\&Center\; Dot;\&Center\; Dot;\&Center\; Dot;+e_{\mathrm{no}}+\&Center\; Dot;\&Center\; Dot;\&CenterDot;+e_N),$ k is the setting coefficient; The detection result discrimination module is used to judge whether the interval 2*a of the above-mentioned measurement error interval is within the range corresponding to the interval of the measurement level set by the merging unit; if so, it is considered that the merging unit meets its level requirements; Meet its grade requirements. 8. The dynamic detection system of the sampling accuracy of substation merging unit electric quantity according to claim 7, is characterized in that: The measurement error interval is 9. The dynamic detection system of the sampling accuracy of substation merging unit electric quantity according to claim 7, is characterized in that: The system also includes a synchronous clock high-precision time calibration unit, which is used to calibrate the digital substation merging unit, so that the measurement results of the merging unit and the standard detection device are at the same time point.