An Automatic Replacement Method for Power Grid Line Anomaly Data Based on EMS

Abstract

This invention discloses an automatic replacement method for abnormal data in power grid lines based on EMS (Electronic Power Grid System). The method includes: generating a path corresponding to line measurements; selecting any one end of the line as the local end and the other end as the remote end; determining the corresponding measurements for the local end and the remote end; identifying whether the data collected at the local end is abnormal; if the data is abnormal, determining whether the condition for replacing the local end data with the remote end data is met; if the replacement condition is met, calculating the replacement value for the abnormal data collected at the local end and executing the replacement. This invention achieves automatic replacement of abnormal data through interaction between the power grid analysis system and the SCADA system, presenting data that better reflects the power grid's operational status to the dispatcher, reducing blind spots in power grid monitoring, improving the dispatcher's monitoring capabilities, and contributing to ensuring the safe and stable operation of the power grid.

Description

Technical Field

[0001] This invention relates to the field of power grid dispatch automation technology, and in particular to an automatic replacement method for abnormal power grid line data based on EMS. Background Technology

[0002] The primary task of power system dispatchers is to ensure the safe, stable, economical, and high-quality operation of the system. With the development of the national economy and the scale of the power grid, higher demands are placed on the reliability and stability of power system operation, increasing the monitoring pressure on dispatchers. First, the power grid is constantly expanding, resulting in more and more data collection and a continuously growing monitoring scope. Second, as crucial power grid connection equipment, the importance of power lines is self-evident, and dispatchers need to know their operational status at all times. Third, power grid data collection involves multiple stages and various hardware devices; any problem in any stage or device can cause anomalies in real-time power grid data collection, affecting the dispatcher's judgment of the true state of the power grid. Based on these three points, in order to ensure the safe and stable operation of the power grid, reduce monitoring blind spots, and improve monitoring levels, it is urgent to study methods for handling anomalies in real-time power grid data collection. Summary of the Invention

[0003] This invention proposes an automatic replacement method for abnormal power grid line data based on EMS. Its purpose is to automatically identify abnormal power grid data, perform data replacement calculations on the abnormal data, reduce blind spots in power grid monitoring, improve dispatchers' ability to monitor the power grid, and ensure the safe and stable operation of the power grid.

[0004] The technical solution of this invention is as follows:

[0005] An automatic replacement method for abnormal power grid line data based on EMS includes the following steps:

[0006] S1: Generate the corresponding path for line measurement, select any one end of the line as the line end, and the other end of the line as the line end, and determine the corresponding measurement for the line end and the line end respectively.

[0007] S2: Identify whether the data collected at the local end of the line is abnormal. If the collected data is abnormal, proceed to step S3.

[0008] S3: Determine whether the condition for data at this end of the line to be replaced by data at the other end of the line is met. If the replacement condition is met, proceed to step S4.

[0009] S4: Calculate the replacement value for the abnormal data collected at this end of the line and perform the replacement.

[0010] Further, the method for generating the corresponding path for line measurement in step S1 is as follows: based on the power grid model, a deep search is carried out from both ends of the line. If the device found at one end of the line is a non-switching disconnector device, the search is stopped. The non-switching disconnector device found is used as the stopping device, and a corresponding path for line measurement is added at this end of the line. The devices in the corresponding path for line measurement include the line itself, the non-grounding disconnector device found, and the stopping device.

[0011] Furthermore, the method for determining the corresponding measurement at this end of the line in step S1 is as follows:

[0012] First, traverse the line at this end and measure the corresponding path. If any switch or disconnector on the path is in an open state, the path is considered disconnected; otherwise, the path is considered connected.

[0013] Then, based on the different path connectivity conditions, determine the corresponding measurements at this end of the line:

[0014] A. If there is only one connected path at the local end of the line, and there is only one active power measurement and one reactive power measurement on each device of the connected path, then the measurement on this path shall be taken as the corresponding measurement at the local end of the line.

[0015] B. If there is only one connected path at this end of the line, but the total number of active or reactive measurements on each device of the connected path is not 1, then it is considered that there is no corresponding measurement at this end of the line.

[0016] C. If there is no connected path at this end of the line or there are two or more connected paths, it is considered that there is no corresponding measurement at this end of the line.

[0017] Furthermore, the method for identifying whether the data collected at the local end of the line is abnormal in step S2 is as follows: if the active and reactive SCADA collection quality codes at the local end of the line are abnormal, then the data collected at the local end of the line is determined to be abnormal.

[0018] Furthermore, the method for identifying whether the data collected at the local end of the line is abnormal in step S2 is as follows: if the active and reactive power at the local end of the line are zero, but the data collection quality code at the other end of the line is normal and not zero, and after network analysis and state estimation calculation, the estimated values ​​of active and reactive power at both the local end and the other end of the line are not zero, then the data collected at the local end of the line is determined to be abnormal.

[0019] Furthermore, the condition for the local data of the line to be replaced by the data of the other end of the line in step S3 is that the following three conditions are met simultaneously:

[0020] First, there is only one connecting path at both the local end and the other end of the line, and there are corresponding measurements for both.

[0021] Second, the remote signaling acquisition quality codes of the switches and disconnectors on the corresponding paths of the measurement at both the local and remote ends of the line are normal.

[0022] Third, the active or reactive power measurements at this end of the line are abnormal, but the active and reactive power measurements at the other end of the line are normal.

[0023] Further, the calculation of the substitute value for the abnormal data collected at the local end of the line in step S4 includes the calculation of the substitute value for the active power at the local end of the line, and the calculation method is as follows:

[0024] If the active power at the other end of the line is greater than zero, then the active power substitution value at this end of the line = -(active power at the other end of the line - active power loss of the line).

[0025] If the active power at the other end of the line is less than zero, then the active power substitution value at this end of the line = -active power at the other end of the line + active power loss of the line.

[0026] Further, the calculation of the substitute value for the abnormal data collected at the local end of the line in step S4 includes the calculation of the reactive power substitute value at the local end of the line, and the calculation method is as follows:

[0027] If the reactive power at the other end of the line is greater than zero, then the reactive power substitution value at the local end of the line = -(reactive power at the other end of the line - reactive power loss of the line) - self-generated reactive power at one end of the line.

[0028] If the reactive power at the other end of the line is less than zero, then the reactive power substitution value at the local end of the line = -reactive power at the other end of the line + reactive power loss of the line - reactive power generated at one end of the line.

[0029] Further, the calculation of the substitute value for the abnormal data collected at this end of the line in step S4 includes the calculation of the substitute value for the current at this end of the line, and the calculation method is as follows:

[0030] Line current substitution value = 1000*sqrt(Line active power substitution value*Line active power substitution value+Line reactive power substitution value*Line reactive power substitution value) / (1.732 * Line voltage reference value).

[0031] Furthermore, the alternative method also includes line traversal, performing steps S1-S4 for each line of the power grid until the line traversal is completed.

[0032] Compared with existing technologies, this invention has the following advantages: By using the SCADA system in the EMS system to identify the quality codes of abnormal data collected from power grid lines, and by using the power grid analysis system for topology analysis and state estimation analysis to identify abnormal power grid data and the operating mode and state of the lines, data inference is performed. Finally, through the interaction between the power grid analysis system and the SCADA system, the abnormal data is automatically replaced, presenting the dispatcher with data that better reflects the power grid operation, reducing blind spots in power grid monitoring, improving the dispatcher's ability to monitor the power grid, and helping to ensure the safe and stable operation of the power grid. Attached Figure Description

[0033] Figure 1 This is a flowchart of the present invention;

[0034] Figure 2 This is a schematic diagram of the path corresponding to the line measurement. Detailed Implementation

[0035] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings:

[0036] like Figure 1 An automatic replacement method for abnormal power grid line data based on EMS includes the following steps:

[0037] S1: Generate the corresponding path for line measurement. Specifically, based on the power grid model, a deep search is performed from both ends of the line. If the equipment found at a certain end of the line is a non-disconnector device (such as busbar, main transformer, capacitor, reactor, generator, etc.), the search is stopped, and the found non-disconnector device is used as the stopping device. A corresponding path for line measurement is added to this end of the line. The equipment in the corresponding path for line measurement includes the line itself, the found non-grounding disconnectors, and the stopping device. Active power, reactive power, current, etc., associated with the path equipment are all measurements of this line.

[0038] Select any one end of the line as the line itself and the other end as the line's opposite end, and determine the corresponding measurements for the line itself and the line's opposite end respectively.

[0039] The method for determining the corresponding measurement at this end of the line is as follows:

[0040] First, traverse the corresponding path at this end of the line. If any switch or disconnector on the path is in an open state, the path is considered disconnected; otherwise, the path is considered connected. Specifically, for example... Figure 2 As shown:

[0041] Legend 1:

[0042] The path is line L-> disconnector 1-> switch K-> disconnector 2-> busbar M, and this path is for disconnection.

[0043] Legend 2:

[0044] The path is line L->disconnector 1->switch K->disconnector 2->bus M, and this path is connected.

[0045] Legend 3:

[0046] Path 1 is line L-> disconnector 1-> switch K-> disconnector 2-> bus M1, this path is disconnection;

[0047] Path 2 is line L-> disconnector 1-> switch K-> disconnector 3-> bus M2, and this path is connected.

[0048] Legend 4:

[0049] The path is line L->disconnector 1->switch K->disconnector 2->main transformer, and this path is connected.

[0050] Legend 5:

[0051] Path 1 is line L-> disconnector 1-> switch K1-> disconnector 2-> main transformer 1, this path is connected;

[0052] Path 2 is line L-> disconnector 3-> switch K2-> disconnector 4-> main transformer 2, this path is disconnection.

[0053] Then, determine the corresponding measurements at this end of the line based on different path connectivity conditions:

[0054] A. If there is only one connected path at the local end of the line, and there is only one active power measurement and one reactive power measurement on each device of the connected path, then the measurement on this path shall be taken as the corresponding measurement at the local end of the line.

[0055] B. If there is only one connected path at this end of the line, but the total number of active or reactive measurements on each device of the connected path is not 1, then it is considered that there is no corresponding measurement at this end of the line.

[0056] C. If there is no connected path at this end of the line or there are two or more connected paths, it is considered that there is no corresponding measurement at this end of the line.

[0057] The method for determining the corresponding measurement at the other end of the line (i.e., the opposite end of the line) is also carried out in the same way as the above three steps ABC.

[0058] S2: Identify whether the data collected at the local end of the line is abnormal. If the collected data is abnormal, proceed to step S3. If the collected data is normal, the line measurement will be directly displayed using the collected data.

[0059] The data collected at this end of the line is considered abnormal if any of the following conditions are met:

[0060] (1) The SCADA acquisition quality codes of active and reactive power at this end of the line are abnormal;

[0061] (2) The active and reactive power at the line end are zero, but the data acquisition quality code at the line end is normal and not zero. After network analysis and state estimation calculation, the active and reactive power state estimates at both the line end and the line end are not zero.

[0062] S3: First, determine whether the condition for local data to be replaced by remote data is met. Specifically, the condition for local data to be replaced by remote data is considered met if all three of the following conditions are met simultaneously:

[0063] (1) There is only one connected path at both the line end and the line end, and there are corresponding measurements.

[0064] (2) The remote signaling acquisition quality codes of the switches and disconnectors on the corresponding paths of the measurement at both the local end and the opposite end of the line are normal;

[0065] (3) The active or reactive power measurement at this end of the line is abnormal, but the active and reactive power measurement at the other end of the line is normal.

[0066] If the substitution conditions are met, proceed to step S4. If the substitution conditions are not met, determine whether there is a substitution flag on the line. If there is a substitution flag, set the line to cancel the substitution flag, cancel the substitution in the SCADA system, and display the line measurement using the collected data. If there is no substitution flag, display the line measurement directly using the collected data.

[0067] S4: Based on the current electrical properties of the line and the active, reactive, and current acquisition values ​​at the opposite end, calculate the replacement values ​​for abnormal acquisition data at the line end, including the replacement values ​​for active power, reactive power, and current at the line end.

[0068] The calculation method for the active power substitution value at this end of the line is as follows:

[0069] If the quality code of the current acquisition at the other end of the line is normal, the current acquisition value is used as the current value at the other end of the line; otherwise, the current value at the other end of the line = 1000*sqrt(active power at the other end of the line*active power at the other end of the line + reactive power at the other end of the line*reactive power at the other end of the line) / (1.732 * reference value of line voltage).

[0070] Line active power loss = 3 * line end current value * line end current value * line resistance value;

[0071] Line reactive power loss = 3 * line end current value * line end current value * line reactance value;

[0072] The self-generated reactive power at one end of the line = the reference value of the line voltage level * the reference value of the line voltage level * the nominal value of the single-end susceptance of the line;

[0073] If the active power at the other end of the line is greater than zero, then the active power substitution value at this end of the line = -(active power at the other end of the line - active power loss of the line).

[0074] If the active power at the other end of the line is less than zero, then the active power substitution value at this end of the line = -active power at the other end of the line + active power loss of the line.

[0075] The method for calculating the reactive power substitution value at this end of the line is as follows:

[0076] If the reactive power at the other end of the line is greater than zero, then the reactive power substitution value at the local end of the line = -(reactive power at the other end of the line - reactive power loss of the line) - self-generated reactive power at one end of the line.

[0077] If the reactive power at the other end of the line is less than zero, then the reactive power substitution value at the local end of the line = -reactive power at the other end of the line + reactive power loss of the line - reactive power generated at one end of the line.

[0078] The method for calculating the substitution value of the line current at this end is as follows:

[0079] Line current substitution value = 1000*sqrt(Line active power substitution value*Line active power substitution value+Line reactive power substitution value*Line reactive power substitution value) / (1.732 * Line voltage reference value).

[0080] After the substitution value is calculated, the line is marked as a substitution point. The power grid analysis system sends the calculated substitution value and the ID number of the data to be substituted to the SCADA system. The SCADA system then changes the value of the relevant data to the substitution value and displays it on the interface, thus completing the substitution.

[0081] Furthermore, the automatic replacement method also includes line traversal, performing steps S1-S4 on each line of the power grid until the line traversal is completed, thereby completing the automatic replacement of abnormal data for the entire power grid lines.

[0082] The terms "line local end" and "line opposite end" in this method are two relative concepts. In specific implementation, if the substitution conditions are met, abnormal data collected at one end of the line can be used to calculate substitution values ​​using data collected at the other end of the line, and the substitution can be performed.

[0083] This method enables automatic monitoring of power grid line operation, real-time data acquisition, and switch status. By analyzing the above parameters, abnormal power grid line data is identified. Based on the needs of power grid personnel for real-time power grid monitoring, the automatically identified abnormal data is used to perform data substitution calculations using power grid characteristics. This reduces blind spots in power grid monitoring, improves dispatchers' monitoring capabilities, and helps ensure the safe and stable operation of the power grid.

[0084] This method helps dispatchers deepen their understanding of the power grid, improve their theoretical level, is more timely and efficient than manual processing, is easy to operate and maintain, facilitates automated power grid management, does not affect the topology of the power grid model, expands system functions, has a high performance-price ratio, and is a one-time investment for long-term use.

Claims

1. An automatic replacement method for abnormal power grid line data based on EMS, characterized in that: Includes the following steps: S1: Generate the corresponding path for line measurement, select any one end of the line as the line end, and the other end of the line as the line end, and determine the corresponding measurement for the line end and the line end respectively. The method for determining the corresponding measurement at this end of the line in step S1 is as follows: First, traverse the line at this end and measure the corresponding path. If any switch or disconnector on the path is in an open state, the path is considered to be disconnected; otherwise, the path is considered to be connected. Then, based on the different path connectivity conditions, determine the corresponding measurements at this end of the line: A. If there is only one connected path at the local end of the line, and there is only one active power measurement and one reactive power measurement on each device of the connected path, then the measurement on this path shall be taken as the corresponding measurement at the local end of the line. B. If there is only one connected path at this end of the line, but the total number of active or reactive measurements on each device of the connected path is not 1, then it is considered that there is no corresponding measurement at this end of the line. C. If there is no connected path at this end of the line or there are two or more connected paths, it is considered that there is no corresponding measurement at this end of the line. S2: Identify whether the data collected at the local end of the line is abnormal. If the collected data is abnormal, proceed to step S3. S3: Determine whether the condition for data at this end of the line to be replaced by data at the other end of the line is met. If the replacement condition is met, proceed to step S4. The condition for the local data of the line to be replaced by the data of the other end of the line in step S3 is that the following three conditions are met simultaneously: First, there is only one connecting path at both the local end and the other end of the line, and there are corresponding measurements for both. Second, the remote signaling acquisition quality codes of the switches and disconnectors on the corresponding paths of the measurement at both the local and remote ends of the line are normal. Third, the active or reactive power measurements at this end of the line are abnormal, but the active and reactive power measurements at the other end of the line are normal. S4: Calculate the replacement value for the abnormal data collected at this end of the line and perform the replacement.

2. The automatic replacement method for abnormal power grid line data based on EMS as described in claim 1, characterized in that: The method for generating the corresponding path for line measurement in step S1 is as follows: based on the power grid model, a deep search is carried out from both ends of the line. If the device found at one end of the line is a non-switching disconnector device, the search is stopped. The non-switching disconnector device found is used as the stopping device, and a corresponding path for line measurement is added at this end of the line. The devices in the corresponding path for line measurement include the line itself, the non-grounding disconnector device found in the search, and the stopping device.

3. The automatic replacement method for abnormal power grid line data based on EMS as described in claim 1, characterized in that: The method for identifying whether the data collected at the local end of the line is abnormal in step S2 is as follows: if the active and reactive SCADA collection quality codes at the local end of the line are abnormal, then the data collected at the local end of the line is determined to be abnormal.

4. The automatic replacement method for abnormal power grid line data based on EMS as described in claim 1, characterized in that: The method for identifying whether the data collected at the local end of the line is abnormal in step S2 is as follows: if the active and reactive power at the local end of the line are zero, but the data collection quality code at the other end of the line is normal and not zero, and after network analysis and state estimation calculation, the estimated values ​​of active and reactive power at both the local end and the other end of the line are not zero, then the data collected at the local end of the line is determined to be abnormal.

5. The automatic replacement method for abnormal power grid line data based on EMS as described in claim 1, characterized in that: Step S4 involves calculating the substitute value for the abnormal data collected at the local end of the line, including the calculation of the active power substitute value at the local end of the line. The calculation method is as follows: If the active power at the other end of the line is greater than zero, then the active power substitution value at this end of the line = -(active power at the other end of the line - active power loss of the line). If the active power at the other end of the line is less than zero, then the active power substitution value at this end of the line = -active power at the other end of the line + active power loss of the line.

6. The automatic replacement method for abnormal power grid line data based on EMS as described in claim 5, characterized in that: Step S4 involves calculating the substitute value for the abnormal data collected at the local end of the line, including the calculation of the reactive power substitute value at the local end of the line. The calculation method is as follows: If the reactive power at the other end of the line is greater than zero, then the reactive power substitution value at the local end of the line = -(reactive power at the other end of the line - reactive power loss of the line) - self-generated reactive power at one end of the line. If the reactive power at the other end of the line is less than zero, then the reactive power substitution value at the local end of the line = -reactive power at the other end of the line + reactive power loss of the line - reactive power generated at one end of the line.

7. The automatic replacement method for abnormal power grid line data based on EMS as described in claim 6, characterized in that: Step S4 involves calculating the substitute value for the abnormal data collected at this end of the line, including the calculation of the substitute value for the current at this end of the line. The calculation method is as follows: The substitution value of the current at this end of the line = 1000*sqrt(the substitution value of the active power at this end of the line * the substitution value of the active power at this end of the line + the substitution value of the reactive power at this end of the line * the substitution value of the reactive power at this end of the line) / (1.732 * the reference value of the line voltage).

8. The automatic replacement method for abnormal power grid line data based on EMS as described in any one of claims 1 to 7, characterized in that: It also includes line traversal, where steps S1-S4 are performed on each line of the power grid until the line traversal is completed.

Images