Meter box impedance anomaly analysis method based on data acquisition

Abstract

The invention discloses a meter box impedance anomaly analysis method based on use and acquisition data, which comprises a data acquisition step, a data recording step, a data processing step, an impedance calculation step and an anomaly analysis step, can obtain the electric meter box impedance of each electric energy meter, can accurately position lines with line aging or device loosening conditions in the electric meter box, and improves the accuracy of the electric meter box impedance analysis. Therefore, the detection difficulty of the line impedance in the electric meter box can be reduced, the accuracy is improved, the connection relationship between each electric energy meter and each phase line at the inlet wire of the electric meter box is obtained by using the screened steady-state data, then the data corresponding to each electric energy meter is used for calculating the impedance of the electric meter box, and the result is stable and reliable. The method has the advantage that the detection of the impedance in the electric meter box is more accurate and simpler.

Description

Technical Field

[0001] The present invention relates to the field of power distribution of electric power systems, and in particular to a method for analyzing meter box impedance anomalies based on usage and sampling data. Background Art

[0002] In the current low-voltage distribution network system, there are many users and corresponding equipment. The scattered installation of various equipment will inevitably cause aging and loose components in the meter box. The possible result is that the internal components and lines of the meter box are too damaged, and the lines or equipment are seriously heated locally. In more serious cases, it may cause equipment damage and cause fires around the lines, posing a serious safety threat to the lives and property of residents. In order to prevent these situations from happening, the health of the meter box is generally judged by the internal impedance of the meter box. When the impedance of the meter box is detected to be greater than the preset threshold, it is considered that the line from the device to the meter box is aging or the components are loose, and maintenance and repair are required in time to ensure the safety of residents' lives and property. However, due to the large number of devices in the meter box, it is difficult to actually detect the line loop impedance in each meter box, and the calculation accuracy is low, making it difficult to characterize the actual situation of the internal structure of the meter box. Summary of the invention

[0003] The present invention provides a meter box impedance anomaly analysis method based on acquisition data, which is used to solve the problems of great difficulty and low accuracy in detecting the impedance in the meter box.

[0004] In order to solve the above technical problems, the present invention discloses the following technical solutions: The present invention provides a meter box impedance anomaly analysis method based on sampled data, which specifically includes a data acquisition step, a data recording step, a data processing step, an impedance calculation step and an anomaly analysis step.

[0005] The data acquisition step is used to obtain the current and voltage data of each electric energy meter connected to the meter box in different time periods Tn, and all the data in each time period are used as a group of data to be processed; the data recording step is used to record the data to be processed including the current value i and voltage value u at time t in the time period Tn. When |i1-i0|>S0, the vector<Tn,u0,i0,u1,i1> Add to the impedance calculation record table, n is a natural number, t0 is the first moment of the time period Tn, t1 is the second moment of the time period T, u0 is the voltage value at the first moment, i0 is the current value at the first moment, u1 is the voltage value at the second moment, i1 is the current value at the second moment, and S0 represents the minimum current mutation amount; the data processing step is to process multiple groups of vectors to be processed separately. If the current of each electric energy meter in a group of vectors to be processed remains stable, then this group of vectors is steady-state data, otherwise this group of vectors is discarded, and the vectors that are not discarded are vectors to be calculated; the impedance calculation step is used to calculate the impedance of the vector to be calculated, and the impedance calculation formula is Ei=|(u1-u0)| / |(i1-i0)|. When the calculated impedance value is greater than an impedance threshold, the impedance is recorded, and the final impedance of the meter box is equal to the sum of the impedances of each vector to be calculated; the abnormal analysis step is used to check the changes in the voltage, current, and power supply circuit impedance of each electric energy meter in the meter box at different times in the time period T, and the reason for the large impedance of the meter box is determined by horizontal comparison and analysis of these data.

[0006] Furthermore, in the data acquisition step, the decimal places of the acquired voltage effective value of the electric energy meter are greater than or equal to 4.

[0007] Furthermore, after the data recording step, a topological relationship acquisition step and a calculation formula acquisition step are also included.

[0008] The topology relationship acquisition step is used to obtain the line topology relationship between the user box, the meter box and the electric energy meter; the user box, the meter box and the electric energy meter are divided into three levels to form a line topology relationship; the calculation formula acquisition step is based on the line topology relationship and the voltage change relationship of the current fluctuation in the electric energy meter to obtain the impedance calculation formula of the electric energy meter.

[0009] Furthermore, in the impedance calculation step, the impedance value is recorded as a median value every day.

[0010] Further, in the impedance calculation step, the impedance threshold is 0.02Ω.

[0011] Furthermore, in the abnormality analysis step, the reasons for the high impedance of the meter box include line aging, grid voltage fluctuation, and electricity theft.

[0012] Compared with the prior art, the present invention has at least the following technical effects: The present invention can obtain the meter box impedance of each electric energy meter, and can accurately locate the lines in the meter box with aging or loose components, thereby reducing the difficulty of detecting the line impedance in the meter box and improving the accuracy. The connection relationship between each electric energy meter and each phase line at the incoming line of the meter box is obtained by using the screened steady-state data, and then the impedance of the meter box is calculated using the data corresponding to each electric energy meter, and the result is stable and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The technical solution of the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0014] Figure 1 A flow chart of a meter box impedance anomaly analysis method based on sampled data provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0015] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention. 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 those skilled in the art without creative work are within the scope of protection of the present invention.

[0016] The present invention provides a meter box impedance anomaly analysis method based on sampled data, which specifically includes step S1) a data acquisition step, step S2) a data recording step, step S3) a data processing step, step S4) a topological relationship acquisition step, step S5) a calculation formula acquisition step, step S6) an impedance calculation step and step S7) an anomaly analysis step.

[0017] S1) Data acquisition step, obtaining the current and voltage data of each electric energy meter connected to the electric energy meter box in different time periods Tn, all the data in each time period is taken as a group of data to be processed, by obtaining the current and voltage data of each electric energy meter connected to the electric energy meter box in each time period T in a day, the impedance of the electric energy meter box is monitored all day long, and the decimal place of the effective value of the voltage of the electric energy meter obtained is greater than or equal to 4 digits.

[0018] Step S2) Data recording step, the recorded data to be processed includes the current value i and voltage value u at time t in the time period Tn. When |i1-i0|>S0, the vector<Tn,u0,i0,u1,i1> Add to the impedance calculation record table, n is a natural number, t0 is the first moment of time period T, t1 is the second moment of time period T, u0 is the voltage value at the first moment, i0 is the current value at the first moment, u1 is the voltage value at the second moment, i1 is the current value at the second moment, and S0 represents the minimum current mutation amount.

[0019] In this embodiment, time, voltage and current are recorded as a vector, which reduces the complexity of the data.<t1,u0,i0,u1,i1> This makes it easier to calculate impedance.

[0020] Step S3) Data processing step, respectively processing multiple groups of vectors to be processed. If the current of each electric energy meter in a group of vectors to be processed remains stable, then this group of vectors is steady-state data. Otherwise, this group of vectors is discarded, and the vectors that are not discarded are the vectors to be calculated. By removing the steady-state data and only calculating the unstable data, the amount of calculation is reduced.

[0021] Step S4) topology relationship acquisition step, obtaining the line topology relationship between the user box, the meter box and the electric energy meter; dividing the user box, the meter box and the electric energy meter into three levels to form a line topology relationship.

[0022] Step S5) is a calculation formula acquisition step. Based on the line topology relationship and the voltage change relationship of the current fluctuation of the electric energy meter, the impedance calculation formula of the electric energy meter is obtained. The two sets of steady-state data corresponding to each electric energy meter are processed to obtain the calculation formula of the meter box impedance of each electric energy meter to calculate the required parameters, that is, vector<t1,u0,i0,u1,i1> , and then calculate to obtain the impedance of each electric energy meter.

[0023] Step S6) Impedance calculation step, calculating the vector impedance to be calculated, the impedance calculation formula is: Ei=|(u1-u0)| / |(i1-i0)| When the calculated impedance value is greater than an impedance threshold, the impedance is recorded. The final impedance of the meter box is equal to the sum of the impedances of each vector to be calculated. The impedance is recorded as a median every day. The impedance threshold is 0.02Ω.

[0024] Step S7) abnormal analysis step, checking the changes in voltage, current, and power supply circuit impedance of each electric energy meter in the meter box at different times within the time period T, and judging the reason for the high impedance of the meter box through horizontal comparison and analysis of these data. The reasons for the high impedance of the meter box include line aging, grid voltage fluctuation, and electricity theft.

[0025] The advantage of the present application is that it provides a meter box impedance anomaly analysis method based on sampled data, which can obtain the meter box impedance of each electric energy meter, and can accurately locate the lines in the meter box where the lines are aged or the components are loose, thereby reducing the difficulty of detecting the line impedance in the meter box and improving the accuracy. The connection relationship between each electric energy meter and each phase line at the incoming line of the meter box is obtained by using the screened steady-state data, and then the meter box impedance is calculated using the data corresponding to each electric energy meter, and the result is stable and reliable.

[0026] The above is a detailed introduction to a meter box impedance anomaly analysis method based on sampling data provided by an embodiment of the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the technical scheme and core idea of ​​the present invention. Ordinary technicians in this field should understand that they can still modify the technical schemes recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents; and these modifications or replacements do not make the essence of the corresponding technical scheme deviate from the scope of the technical scheme of the embodiments of the present invention.

Claims

1. A method for analyzing meter box impedance anomaly based on sampling data, characterized in that: The specific steps include: Data acquisition step, acquiring current and voltage data of each electric energy meter connected to the electric meter box in different time periods Tn, and all data in each time period is taken as a group of data to be processed; The data recording step includes the current value i and the voltage value u at time t within the time period T. When |i1-i0|>S0, the vector<Tn,u0,i0,u1,i1> Add to the impedance calculation record table, n is a natural number, t0 is the first moment of the time period T, t1 is the second moment of the time period T, u0 is the voltage value at the first moment, i0 is the current value at the first moment, u1 is the voltage value at the second moment, i1 is the current value at the second moment, S0 represents the minimum current mutation amount; The data processing step is to process the multiple groups of vectors to be processed respectively. If the current of each electric energy meter in a group of vectors to be processed remains stable, then the group of vectors is steady-state data. Otherwise, the group of vectors is discarded, and the vectors that are not discarded are the vectors to be calculated. Impedance calculation steps: calculate the vector impedance to be calculated. The impedance calculation formula is: Ei=|(u1-u0)| / |(i1-i0)| When the calculated impedance value is greater than an impedance threshold, the impedance is recorded, and the final impedance of the electric meter box is equal to the sum of the impedances of the vectors to be calculated; The abnormal analysis step is to check the changes in voltage, current, and power supply circuit impedance of each electric energy meter in the meter box at different times during the time period T, and to determine the cause of the high impedance of the meter box through horizontal comparative analysis of these data.

2. The meter box impedance anomaly analysis method based on sampling data according to claim 1, characterized in that: In the data acquisition step, The decimal places of the obtained voltage effective value of the electric energy meter are greater than or equal to 4.

3. The meter box impedance anomaly analysis method based on sampling data according to claim 1, characterized in that: After the data recording step, the method further includes: The topology relationship acquisition step is to obtain the line topology relationship between the user box, the meter box and the electric energy meter; the user box, the meter box and the electric energy meter are divided into three levels to form a line topology relationship; The calculation formula acquisition step is to obtain the impedance calculation formula of the electric energy meter based on the line topology relationship and the voltage change relationship caused by the current fluctuation of the electric energy meter.

4. The meter box impedance anomaly analysis method based on sampling data according to claim 1, characterized in that: In the impedance calculation step, The median value of impedance was recorded every day.

5. The meter box impedance anomaly analysis method based on sampling data according to claim 1, characterized in that: In the impedance calculation step, The impedance threshold is 0.02Ω.

6. The meter box impedance anomaly analysis method based on sampling data according to claim 1, characterized in that: In the anomaly analysis step, The reasons for the high impedance of the meter box include line aging, grid voltage fluctuations, and electricity theft.

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