Research on the Transformer Condition Assessment Based on the Entropy Weight Method

As one of the important hinge equipments in the electric power system, the operating reliability of power transformer has deep influences on security and stability of power system. In order to guide transformer maintenance and assess the risk of the electric power system, it is of important significance to know the state of the running insulation of transformer in time and accurately. Based on the analysis of transformer state parameters, the method determining the evaluation index weight has been studied; methods of entropy value objective weight and improved analytic hierarchy process subjective weight have been combined to calculate the weighting coefficients of evaluation indexes. Its correctness has been verified by analyzing examples of transformer operation.

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Electric power system simulation for risk assessment of power transformer failure under external short-circuit conditions

2017 IEEE First Ukraine Conference on Electrical and Computer Engineering (UKRCON) ◽

10.1109/ukrcon.2017.8100527 ◽

2017 ◽

Author(s):

E. I. Bardyk ◽

N. P. Bolotnyi

Keyword(s):

Risk Assessment ◽

Power System ◽

Electric Power ◽

Power Transformer ◽

System Simulation ◽

Short Circuit ◽

Electric Power System ◽

Power System Simulation

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Evaluation of Power System Black-Start Schemes Based on Improved DEA/AHP Evaluation Model

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.644-650.3579 ◽

2014 ◽

Vol 644-650 ◽

pp. 3579-3582 ◽

Cited By ~ 3

Author(s):

Cheng Guang Shi ◽

Tao Liu

Keyword(s):

Power System ◽

Evaluation Model ◽

Electric Power System ◽

Entropy Weight ◽

Group Evaluation ◽

Multiple Attribute ◽

Entropy Weight Method ◽

Focus Type ◽

Weight Method ◽

Scheme Evaluation

Aiming at multiple attribute in electric power system black start scheme evaluation, the characteristics of the subjective and objective weights are difficult to determine; Entropy weight method can not ensure independence; DEA model can't completely sorted and judgment matrix all of 1 problem may come up, this paper puts forward improved DEA/AHP model. According to the index of evaluation index focus type optimal selection, the worst plan to join the group evaluation schemes for evaluation. This method not only can guarantee the independence of the scheme can achieve full sort again, avoid the process of calculating the weight at the same time, to enhance the objectivity. The method is simple in calculation and reliable results, tianjin power grid black start scheme evaluation results prove the effectiveness of this method.

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Weight Calculation of GSM-R Network Quality of Service Evaluation Indexes Based on Analytic Hierarchy Process and Entropy Weight Method

Journal of Physics Conference Series ◽

10.1088/1742-6596/1828/1/012089 ◽

2021 ◽

Vol 1828 (1) ◽

pp. 012089

Author(s):

Liangde Ma ◽

Zihui Zuo ◽

Bo Zhao ◽

Lincan Li

Keyword(s):

Service Evaluation ◽

Entropy Weight ◽

Analytic Hierarchy ◽

Evaluation Indexes ◽

Weight Calculation ◽

Entropy Weight Method ◽

Weight Method ◽

Network Quality ◽

Hierarchy Process

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DETERMINATION OF “WEAK” BY POWER TRANSFORMERS RELIABILITY OF POWER SYSTEMS ACCORDING TO THE RESULTS OF FAILURE RISK ASSESSMENT UNDER EXTERNAL SHORT CIRCUITS

KPI Science News ◽

10.20535/kpisn.2021.2.236952 ◽

2021 ◽

Author(s):

Eugeniy I. Bardik ◽

Mykola P. Bolotniy ◽

Yaroslav S. Koval

Keyword(s):

Mathematical Model ◽

Risk Assessment ◽

Power System ◽

Electric Power ◽

Power Transformer ◽

Short Circuit ◽

Electric Power System ◽

Power Transformers ◽

Electrical Network ◽

Failure Risk

Background. The increase of technological violation intensity and its consequences severity is caused mainly by objectively existing aging and service life depletion of electrical equipment. The power industry liberalization exacerbates the reliable operation problem of the power system and requires identification of power system operation accompanied by the maximum emergency risk with possible cascade accidents development. Therefore, the model development task for assessment of the equipment failure risk based on the diagnostic results of technical condition in particular under short circuit in the external network is relevant today. Objective. The aim of the work is to develop a fuzzy mathematical model for probability assessment of power transformer failure in the presence of a windings defect, short circuit in external network and emergency risk assessment under power transformers out of service. Methods. The fuzzy set theory and fuzzy logic were used for developing a mathematical model of risk assessment of power trans- former failure. The problems of determining the “weak” in terms of power transformers reliability of power systems based on the results of failure risk assessment due to external short circuits were solved by methods of fuzzy logic and probabilistic-statistical simulation of electric power system modes. Results. The necessity of complex simulation of electric power system modes is substantiated for probability assessment of power transformer failure under electrical network disturbances. The simulation of technical condition of power transformer windings was carried out. The short circuit influence on operability level of power transformers of electric power system was investigated. The quantitative indicators of operational risk of electric power system were determined under power transformers out of service. Conclusions. The linguistic mathematical model for estimating the failure probability of power transformer windings in the presence of defect and short circuit in electrical network has been developed to determine the quantitative indicators of emergency risk in power system.

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