Arrangement method for power failure maintenance plan of large-user line

Abstract

The invention discloses a method for arranging a power failure maintenance plan of a large-user line. The method comprises the following steps: constructing comprehensive maintenance cost of power failure maintenance; dividing maintenance time periods of power-off maintenance, and determining the suitability of the power-off maintenance; and dividing the suitability into maintenance time periods according to a proportion, putting the updated maintenance time periods into a rectangular coordinate system, and determining final maintenance time according to a time period aggregation condition. According to the method, the power failure maintenance cost is quantified by constructing the comprehensive maintenance cost model, so that planning personnel have quantitative understanding of the power failure maintenance cost, and the method is more accurate and objective compared with traditional perceptual evaluation; three-level maintenance time periods are set, so that the flexibility of power failure maintenance plan arrangement can be enhanced, and the situation that maintenance work cannot be carried out due to the influence of force majeure factors such as weather is prevented; the power failure maintenance work of the next year is predicted by considering data sub-weights in recent five years, the accuracy is higher, the power failure maintenance suitability can better reflect the proper power failure time in one year, and the method is more objective compared with the traditional technology.

Description

Technical Field

[0001] This invention relates to the field of maintenance planning, specifically a method for planning power outage maintenance of large user lines. Background Technology

[0002] Power outage maintenance of electrical equipment is conducted to maintain the equipment in good working condition, improve the reliability of power grid operation, reduce the occurrence of equipment emergency shutdowns, and provide users with a better power experience.

[0003] At present, various large and medium-sized enterprises are the backbone of the local economic development, and ensuring reliable power supply for large users is the responsibility of power supply companies. According to equipment operation and maintenance procedures, various equipment should be shut down for maintenance according to the maintenance cycle. However, power outages can have a significant impact on enterprise production and operation. Finding a balance between ensuring power supply to users and power outage equipment maintenance has become a new direction in the research of power outage planning.

[0004] Large users are typically supplied directly via dedicated 110kV or 220kV lines. Strictly adhering to equipment maintenance schedules during power outages inevitably impacts production. Given the heavy production demands and large electricity loads of large users, implementing power outage maintenance plans is difficult. Maintenance is often arranged ad hoc based on the user's production downtime, placing significant strain on the maintenance department's capacity and coordination abilities. Furthermore, numerous uncertainties during maintenance can prolong outage times, greatly affecting the power user experience and reducing user satisfaction. Moreover, current power outage maintenance plans are often arranged by specialists based on past experience, lacking a scientific approach. Summary of the Invention

[0005] To address the current difficulty in scheduling power outage maintenance plans for large user lines, this invention proposes a method for scheduling power outage maintenance plans for large user lines.

[0006] The purpose of this invention is to provide a method for scheduling power outage maintenance for large user lines, so as to improve the rationality and feasibility of power outage maintenance scheduling, and reduce the power outage maintenance costs on the user side and the maintenance costs of the maintenance department.

[0007] The objective of this invention can be achieved as follows: a method for arranging a power outage maintenance plan for a large user line, comprising:

[0008] Develop a comprehensive maintenance cost structure for power outage repairs;

[0009] Divide the maintenance period for power outages and determine the appropriateness of power outage maintenance;

[0010] The suitability is proportionally allocated to maintenance periods, and the updated maintenance periods are placed in a rectangular coordinate system. The final maintenance time is determined based on the clustering of time periods.

[0011] The comprehensive maintenance cost includes user-side costs and maintenance-side costs.

[0012] The user-side cost mentioned above is the direct economic loss C incurred by the user due to the power outage. D Specifically

[0013] ,

[0014] Where: Pi is the active power of the line on day i; T is the maintenance duration; p is the impact coefficient of a single power outage on the enterprise's production; m is the number of times the same line is maintained by power outage within a year; U is the line value coefficient, which is positively correlated with the line voltage level; L is the added value of the enterprise's products, which is determined by the type of enterprise's products.

[0015] Maintenance costs are labor costs C. R Specifically:

[0016] ,

[0017] In the formula: Di is the number of staff members working outside the work group on day i; S is the maintenance workload, which is positively correlated with the line voltage level; T is the maintenance duration; Q is the staff wage;

[0018] The comprehensive maintenance cost C is:

[0019] .

[0020] The aforementioned maintenance periods are divided into three tiers (A, B, and C) based on the overall maintenance cost, from highest to lowest. Additionally, referencing power outage maintenance data from the past five years, the suitability of power outage maintenance for each year is proportionally allocated to each maintenance period. The specific allocation percentages are as follows:

[0021] ,

[0022] In the formula: A is the suitability percentage of the A-level maintenance period within a single year; B is the suitability percentage of the B-level maintenance period within a single year; and C is the suitability percentage of the C-level maintenance period within a single year.

[0023] The coordinate system uses the year as the vertical axis and the number of days in a year as the horizontal axis. The optimal maintenance time is the period with the most concentrated maintenance time in the coordinate system.

[0024] This invention quantifies power outage maintenance costs by constructing a comprehensive maintenance cost model, allowing planning personnel to have a quantitative understanding of these costs, which is more accurate and objective compared to traditional subjective evaluations. Establishing a three-tiered maintenance timeframe enhances the flexibility of power outage maintenance planning, preventing maintenance work from being halted due to unforeseen circumstances such as weather. By weighting data from the past five years, it predicts power outage maintenance work for the following year with higher accuracy and greater individual relevance, minimizing the impact of unforeseen circumstances. The power outage suitability assessment effectively reflects appropriate outage times throughout the year, offering a more objective perspective compared to traditional techniques. Attached Figure Description

[0025] Figure 1 This is a logic flowchart of the present invention;

[0026] Figure 2 This is a schematic diagram illustrating the suitability confirmation of power outage maintenance according to the present invention.

[0027] Figure 3 This is a schematic diagram of a case study for confirming the suitability of power outage maintenance according to the present invention.

[0028] Figure 4 This is a schematic diagram of Case 2 for confirming the suitability of power outage maintenance according to the present invention. Detailed Implementation

[0029] The invention will now be described in further detail with reference to the accompanying drawings:

[0030] This invention relates to a method for scheduling power outages for maintenance of large customer lines, comprising:

[0031] I. Constructing a comprehensive maintenance cost

[0032] The cost of power outage maintenance generally includes three aspects: the grid side, the user side, and the maintenance side.

[0033] On the power grid side: Power outages weaken the power grid structure and increase the risk of accidents.

[0034] On the user side: Power outages cause direct economic losses to enterprises.

[0035] Maintenance side: The labor costs required for maintenance work.

[0036] (1) User-side costs

[0037] Power outages for users will inevitably affect the normal production of enterprises and cause direct economic losses. This project constructs the following function to reflect the economic losses of users.

[0038]

[0039] In the formula: Pi is the active power of the line on day i; T is the maintenance duration; p is the impact coefficient of a single power outage on the enterprise's production; m is the number of times the same line is shut down for maintenance within a year; U is the line value coefficient, which is positively correlated with the line voltage level; L is the added value of the enterprise's products, which is determined by the type of enterprise's products.

[0040] (2) Maintenance costs

[0041] For power outage maintenance, the main cost on the maintenance side is labor cost. This project constructs the following function to reflect the maintenance cost.

[0042]

[0043] In the formula: Di is the number of staff members working outside the shift on day i; S is the maintenance workload, which is positively correlated with the line voltage level; T is the maintenance duration; and Q is the staff wage.

[0044] (3) Overall maintenance cost

[0045] As the formula shows, user-side costs and maintenance-side costs are not on the same order of magnitude. Simply summing them based on their proportions would inevitably lead to a "larger number eating up a smaller number" situation, where maintenance-side costs are negligible compared to user-side costs, having no impact on the overall maintenance cost. To address this issue, this project establishes an overall maintenance cost model as the product of the two costs and takes the cube root of the maintenance-side cost to reduce its impact on the overall maintenance cost, highlighting user needs and prioritizing customer service. The overall maintenance cost is:

[0046] .

[0047] The optimal power outage maintenance time is when the overall maintenance cost is minimized. To prevent the overall maintenance cost from being zero due to a zero number of workers on-site, which would significantly impact the results, this project sets the minimum number of workers on-site, Di, to be 1.

[0048] II. Division of Maintenance Periods

[0049] To improve the resilience and flexibility of maintenance planning, the maintenance time periods are rated based on the overall annual maintenance cost of the line, with three levels: A, B, and C. All three maintenance time periods can be used as time options for carrying out power outage maintenance work.

[0050] Table 1. Maintenance Period Division

[0051] III. Determining the suitability of power outage maintenance

[0052] (1) Influence of year factor

[0053] The closer the year, the higher the historical data reference value. Table 2 shows the proportion of data value from the previous 5 years based on the length of time.

[0054] Table 2. Percentage of Influence of Year Factors

[0055] (2) Factors affecting the third-level maintenance period

[0056] As can be seen from the above analysis, the A, B and C maintenance periods can all be used as preliminary options for power outage planning. Considering the impact of each maintenance period on the work, the suitability of power outage maintenance in each year is proportionally allocated to each maintenance period. The specific allocation ratio is shown in Table 3.

[0057] Table 3 Rating Standards Percentage

[0058]

[0059] Since the maintenance periods for levels B and C may not be unique, the appropriateness percentage of each individual maintenance period needs to be calculated mathematically.

[0060]

[0061] In the formula: A is the suitability percentage of the A-level maintenance period within a single year; B is the suitability percentage of the B-level maintenance period within a single year; and C is the suitability percentage of the C-level maintenance period within a single year.

[0062] (3) Calculation of the suitability of power outage

[0063] The obtained maintenance periods for levels A, B, and C over the past five years are distributed sequentially in a rectangular coordinate system, with the year as the vertical axis and the 365 days of the year as the horizontal axis. Based on the inherent maintenance time width of the lines, areas with higher suitability for maintenance are identified within the coordinate system. Future power outage maintenance schedules are then determined based on these selected areas. For example... Figure 1 As shown.

[0064] The following is a detailed explanation using a 110kV large-user power supply line in a 220kV substation in a certain city as an example:

[0065] This project analyzed maintenance data from a municipal substation over the past three years. The data shows that in the previous year, there were 27 major overhaul and technical upgrade projects for 220kV lines and 107 for 110kV lines. In the previous two years, there were 23 such projects for 220kV lines and 58 for 110kV lines. In the previous three years, there were 23 such projects for 220kV lines and 90 for 110kV lines. Detailed statistics are shown in Table 4 below.

[0066] Table 4 Statistical data on power outage maintenance work

[0067]

[0068] As shown in the table, the average maintenance time for 220kV lines in a certain city over the past three years was 6.26 days, and the average maintenance time for 110kV lines was 4.52 days. Therefore, this paper sets the maintenance time T for 220kV lines to 7 days and the maintenance time T for 110kV lines to 5 days.

[0069] (3) Calculation of the suitability of power outage

[0070] The obtained maintenance periods for levels A, B, and C over the past five years are sequentially distributed in a rectangular coordinate system, with the year as the ordinate and the date as the abscissa. Based on the voltage level of the maintenance lines, areas with high suitability for maintenance are identified within the coordinate system with appropriate time spans. Figure 2 As shown.

[0071] Since the C-level maintenance periods in the previous year and the previous two years were not unique, the appropriateness percentage of maintenance periods for each year in the past 5 years for this line is shown in Table 8 below.

[0072] Table 8. Proportion of Level III Maintenance Periods in Each Year

[0073] like Figure 3 This shows the distribution of Level 3 maintenance periods for Line 767 at a certain station over the past 5 years. In the previous year, the comprehensive maintenance cost calculation revealed that the Level A maintenance period was day 278, and there were 13 Level B maintenance periods, specifically days 277, 279, and 280. There were no Level C maintenance periods. In the previous two years, the comprehensive maintenance cost calculation revealed that the Level A maintenance period was day 39, the Level B maintenance period was day 40, and there were no Level C maintenance periods. In the previous three years, the comprehensive maintenance cost calculation revealed that the Level A maintenance period was day 275, the Level B maintenance period was day 274, and there were two Level C maintenance periods, specifically days 273 and 276. In the previous four years, the comprehensive maintenance cost calculation revealed that the Level A maintenance period was day 39, the Level B maintenance period was day 38, and there were no Level C maintenance periods. The comprehensive maintenance cost calculation for the first five years shows that the Class A maintenance period is day 275, there are two Class B maintenance periods, namely day 274 and day 276, and the Class C maintenance period is day 20.

[0074] It can be seen that the three-stage maintenance period for Line 767 can be roughly divided into two phases. The suitability of the first phase of power outage maintenance is 40%, and the suitability of the second phase of power outage maintenance is 59%. If power outage maintenance is required for Line 767 in a given year, it would be more appropriate to schedule the power outage maintenance work around the 40th or 275th day.

[0075] like Figure 4This shows the distribution of Level 3 maintenance periods for Line 803 at a certain station over the past 5 years. In the previous year, the comprehensive maintenance cost calculation revealed that the Level A maintenance period was day 66, there were two Level B maintenance periods (days 67, 68, and 280), and the Level C maintenance period was day 65. In the previous two years, the comprehensive maintenance cost calculation revealed that the Level A maintenance period was day 58, with no Level B or Level C maintenance periods. In the previous three years, the comprehensive maintenance cost calculation revealed that the Level A maintenance period was day 57, there were three Level B maintenance periods (days 53, 54, and 55), and the Level C maintenance period was day 58. In the previous four years, the comprehensive maintenance cost calculation revealed that the Level A maintenance period was day 61, with no Level B maintenance periods, and the Level C maintenance period was day 38. The calculation of the comprehensive maintenance cost for the first five years shows that the Class A maintenance period is day 46, there is no Class B maintenance period, and there are two Class C maintenance periods, day 45 and day 47 respectively.

[0076] It can be seen that the third-level maintenance period is roughly concentrated in the first quarter, around 55 days a month. By selecting the time range on the rectangular coordinate system using a dashed box with a time width of 5 days, the suitability of power outage maintenance is the highest at 79.45%, which falls within the time range of day 57 to 61. This indicates that if power outage maintenance work is to be carried out on line 803 in the same year, it would be more appropriate to carry out the power outage work within this time range.

Claims

1. A method for arranging a power outage maintenance plan for a large user line, characterized in that, include: Develop a comprehensive maintenance cost structure for power outage repairs; Divide the maintenance period for power outages and determine the appropriateness of power outage maintenance; The suitability is proportionally allocated to maintenance periods, and the updated maintenance periods are placed in a rectangular coordinate system. The final maintenance time is determined based on the clustering of time periods.

2. The method for arranging a power outage maintenance plan for a large user line according to claim 1, characterized in that, The comprehensive maintenance cost includes user-side costs and maintenance-side costs. The user-side cost mentioned above is the direct economic loss C incurred by the user due to the power outage. D Specifically ， Where: Pi is the active power of the line on day i; T is the maintenance duration; p is the impact coefficient of a single power outage on the enterprise's production; m is the number of times the same line is maintained by power outage within a year; U is the line value coefficient, which is positively correlated with the line voltage level; L is the added value of the enterprise's products, which is determined by the type of enterprise's products. Maintenance costs are labor costs C. R Specifically: ， In the formula: Di is the number of staff members working outside the work group on day i; S is the maintenance workload, which is positively correlated with the line voltage level; T is the maintenance duration; Q is the staff wage; The comprehensive maintenance cost C is: 。 3. The method for arranging a power outage maintenance plan for large user lines according to claim 2, characterized in that, The aforementioned maintenance periods are divided into three tiers (A, B, and C) based on the overall maintenance cost, from highest to lowest. Additionally, referencing power outage maintenance data from the past five years, the suitability of power outage maintenance for each year is proportionally allocated to each maintenance period. The specific allocation percentages are as follows: ， In the formula: A is the suitability percentage of the A-level maintenance period within a single year; B is the suitability percentage of the B-level maintenance period within a single year; and C is the suitability percentage of the C-level maintenance period within a single year.

4. The method for arranging a power outage maintenance plan for a large user line according to claim 1, characterized in that, The coordinate system uses the year as the vertical axis and the number of days in a year as the horizontal axis. The optimal maintenance time is the period with the most concentrated maintenance time in the coordinate system.

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