CN-121998615-A - Method and system for evaluating and deciding full life cycle performance of transformer in coastal region

CN121998615ACN 121998615 ACN121998615 ACN 121998615ACN-121998615-A

Abstract

The application relates to a method and a system for evaluating and deciding the performance of the whole life cycle of a transformer in coastal areas, belonging to the technical field of asset management and reliability evaluation of electric power systems. The method comprises the steps of collecting multi-source data of the transformer, carrying out standardized processing, constructing an environment equivalent intensity index according to environment data, fusing operation load and state monitoring data, constructing a comprehensive degradation index reflecting thermal aging and corrosion damage, determining a reference failure rate based on service life, correcting the reference failure rate by utilizing the comprehensive degradation index to obtain a time-varying failure rate, calculating the cost and carbon emission of the whole life cycle based on the time-varying failure rate and economic data, and solving an optimal replacement strategy with the lowest cost and carbon emission as targets. The method solves the problems that the traditional method is difficult to quantify the influence of coastal environment, the health state of equipment cannot be dynamically evaluated and multi-objective optimization decision-making is performed, and realizes the lean and green low-carbon management of the whole life cycle of the transformer.

Inventors

WANG YING
QIU SHIJIN
KE YE
LIN JIAWEI
ZHU XUEMEI
ZENG CONG

Assignees

国网福建省电力有限公司经济技术研究院
国网福建省电力有限公司

Dates

Publication Date: 20260508
Application Date: 20260116

Claims (10)

1. The method for evaluating and deciding the full life cycle performance of the transformer in the coastal area is characterized by comprising the following steps of: The method comprises the steps of collecting multi-source data of transformers in coastal areas, and carrying out standardized processing, wherein the multi-source data comprise environment data, operation load data, state monitoring data and economic data; constructing an environment equivalent intensity index according to the environment data, and constructing a comprehensive degradation index reflecting the thermal aging damage index and the corrosion damage index based on the environment equivalent intensity index, the operation load data and the state monitoring data; Determining a reference fault rate based on the service life of the transformer, and correcting the reference fault rate by utilizing the comprehensive degradation index and the operation load data to obtain a time-varying fault rate; calculating the total life cycle cost and carbon emission of the transformer based on the time-varying failure rate and the economic data; And solving an optimal coastal region transformer replacement strategy by taking the minimum total life cycle cost and carbon emission as targets.
2. The method for evaluating and deciding the full life cycle performance of the transformer in coastal areas according to claim 1, wherein the calculation formula of the environment equivalent intensity index is: ; Wherein: at the point of time for transformer i Is a combination of the environmental equivalent intensity index of (a); 、、、、 respectively normalizing the ambient air temperature, the relative humidity, the salt fog concentration, the wind speed and the pollution grade; 、、、、 And (5) fitting a weight coefficient through logistic regression of the historical fault data.
3. The method for evaluating and deciding the full life cycle performance of the transformer in coastal areas according to claim 2, wherein the comprehensive degradation index is obtained by weighting and calculating a thermal aging damage index and a corrosion damage index, and wherein: The thermal ageing damage index is obtained by cumulatively calculating the life damage increment of each time step based on hot spot temperature data and a transformer design life curve; and the corrosion damage index is obtained by estimating the corrosion depth through a corrosion model based on the environment equivalent intensity index and the service life of the transformer.
4. The method for evaluating and deciding the full life cycle performance of the transformer in coastal areas according to claim 3, wherein the time-varying failure rate is calculated by a proportional risk model, and specifically comprises the following steps: ; Wherein: at the point of time for transformer i Time-varying failure rate of (a); 、、、、 respectively obtaining average values of comprehensive degradation indexes, environment equivalent intensity indexes, load rates, preventive maintenance marks and overhaul marks in a sliding time window; 、、、、 The coefficients of the comprehensive degradation index, the environment equivalent strength index, the load factor, the preventive maintenance sign and the overhaul sign are fitted through survival analysis.
5. The method for evaluating and deciding the life cycle performance of a transformer in coastal regions according to claim 4, wherein the step of fitting the survival analysis comprises: Constructing a history sample set, wherein the history sample set records the first fault time or the deleting time of each transformer and feature vectors at corresponding time points, and the feature vectors comprise comprehensive degradation indexes, environment equivalent strength indexes, load rates, preventive maintenance marks and sliding window average values of overhaul marks; and constructing an objective function by using the partial likelihood function, and estimating and obtaining a coefficient estimated value reflecting the influence degree of each feature on the fault risk by maximizing the objective function.
6. The method for evaluating and deciding the full life cycle performance of the transformer in coastal areas according to claim 1, wherein the calculation formula of the full life cycle cost is: ; Wherein: The total life cycle cost of the transformer i; initial purchase and installation costs for transformer i; annual operating maintenance costs, fault related costs and electrical energy consumption costs, respectively; is the discount factor, y is the estimated year, belongs to the estimated period set 。
7. The method for evaluating and deciding the full life cycle performance of the transformer in the coastal region according to claim 1, wherein the standardized processing comprises the steps of establishing a unified time axis, aligning multi-source data at time points, and carrying out missing value processing, outlier marking and standardized conversion on the numerical value characteristics.
8. A coastal zone transformer full life cycle performance assessment and decision system comprising: The system comprises a data acquisition module, a data processing module and a data processing module, wherein the data acquisition module acquires multi-source data of a transformer in a coastal area and performs standardized processing, and the multi-source data comprises environment data, operation load data, state monitoring data and economic data; The comprehensive degradation index calculation module is used for constructing an environment equivalent intensity index according to the environment data and constructing a comprehensive degradation index reflecting the thermal aging damage index and the corrosion damage index based on the environment equivalent intensity index, the operation load data and the state monitoring data; the time-varying fault rate determining module is used for determining a reference fault rate based on the service life of the transformer, and correcting the reference fault rate by utilizing the comprehensive degradation index and the operation load data to obtain the time-varying fault rate; the cost calculation module is used for calculating the total life cycle cost and carbon emission of the transformer based on the time-varying failure rate and the economic data; And the replacement strategy optimization decision module is used for solving the optimal coastal region transformer replacement strategy by taking the minimum total life cycle cost and carbon emission as targets.
9. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor implements the coastal zone transformer life cycle performance assessment and decision method of claims 1-7 when the program is executed by the processor.
10. A computer readable storage medium having stored thereon a computer program, which when executed by a processor implements the coastal zone transformer life cycle performance assessment and decision method of claims 1-7.

Description

Method and system for evaluating and deciding full life cycle performance of transformer in coastal region Technical Field The application relates to the technical field of asset management and reliability evaluation of electric power systems, in particular to a method and a system for evaluating and deciding the full life cycle performance of a transformer in coastal areas. Background In coastal region electric network, large-capacity oil immersed transformer is operated under high humidity, high salt fog, strong wind and dirt deposition for a long time, and its aging and corrosion process of insulation system, metal component and sealing structure is obviously faster than that of inland region, and is easy to have hidden trouble such as leakage, discharge and short circuit. With the continuous construction of new energy bases, power grid interconnection projects and important load centers in coastal areas, the large-load operation of transformers, frequent tide fluctuation and extreme weather superposition are carried out, so that the deviation between the actual life and the design life of equipment is aggravated, the unified life assumption and static operation and maintenance strategy given by the traditional experience curve or periodic test results are difficult to reflect the actual health condition and failure trend of the equipment in coastal environments in time, and larger uncertainty and risk are brought to the safe operation and asset planning of the power grid. In the prior art, the state evaluation of the transformer mainly uses single-point detection results such as oil chromatography, electrical test, partial discharge detection and the like, and is comprehensively judged by expert scoring, fuzzy evaluation or simple life reduction coefficient, so that the system utilization of multi-source data such as coastal environment strength, operation load, thermal aging, corrosion degradation and the like is often lacked, and the coupling relation among fault rate evolution, outage risk, operation and maintenance cost and loss is rarely quantified from the full life cycle view. Meanwhile, the existing operation and maintenance and replacement decision method mostly adopts rough limit expiration or fault times overrun rules, and cannot uniformly balance the degradation state and reliability level of equipment with the full life cycle economy and carbon emission constraint, so that the lean management of transformer assets in coastal areas and the realization of green low-carbon targets are restricted. Therefore, it is necessary to provide a method for evaluating and deciding the full life cycle performance of the transformer by considering the coastal environment strength, the operation condition, the operation and maintenance behavior and the economic constraint, and to relate the degradation mechanism, the reliability index and the full life cost, so as to provide a quantifiable, optimizable and traceable decision basis for reinforcing, overhauling and replacing the transformer in coastal areas. Disclosure of Invention In order to solve the technical problems, the invention provides a method and a system for evaluating and deciding the full life cycle performance of a transformer in coastal areas. The technical scheme of the invention is as follows: The invention provides a method for evaluating and deciding the full life cycle performance of a transformer in coastal areas, which comprises the following steps: The method comprises the steps of collecting multi-source data of transformers in coastal areas, and carrying out standardized processing, wherein the multi-source data comprise environment data, operation load data, state monitoring data and economic data; constructing an environment equivalent intensity index according to the environment data, and constructing a comprehensive degradation index reflecting the thermal aging damage index and the corrosion damage index based on the environment equivalent intensity index, the operation load data and the state monitoring data; Determining a reference fault rate based on the service life of the transformer, and correcting the reference fault rate by utilizing the comprehensive degradation index and the operation load data to obtain a time-varying fault rate; calculating the total life cycle cost and carbon emission of the transformer based on the time-varying failure rate and the economic data; And solving an optimal coastal region transformer replacement strategy by taking the minimum total life cycle cost and carbon emission as targets. Preferably, the calculation formula of the environment equivalent intensity index is as follows: ; Wherein: at the point of time for transformer i Is a combination of the environmental equivalent intensity index of (a);、、、、 respectively normalizing the ambient air temperature, the relative humidity, the salt fog concentration, the wind speed and the pollution grade; 、、、、 And (5) fitting a weight coefficient th