Study of Technical and Economic Indicators of Power Transformers Taking into Account the Conditions of Operation

Abstract

The article presents research, aimed at finding the optimal power of transformers through the analysis of technical and economic indicators that reflect the cost of electrical energy transformation. During the research, the characteristics corresponding to the existing parametric intervals of power transformers of 110 kV electric grid were used. The decision regarding the need to find the optimal power of transformers is made by evaluating the ratios of the components in the techno-economic model of costs for the transformation of electrical energy, the change of which is due to the deviation of the operational characteristics of the power transformer from economically feasible values. When determining the economically feasible rated power, the indicators of the improved technical and economic model of the 110 kV transformers used in the electric network are taken as the basic ones. In the paper, the economically feasible values are the ratios in the techno-economic model of costs for the transformation of electrical energy determined using the criterion method and reflected by the criteria of the similarity of the objective function. In order to find the economically feasible power of the transformer, the techno-economic model is improved and formed in a simplified form. Similarity criteria, which were found using the developed techno-economic model, reflect the ratio of component costs according to the criterion of minimum discounted costs. In the process of finding the optimal power of transformers, expressions were developed for calculating the economically feasible power and the corresponding amount of costs for the transformation of electrical energy. According to the developed expressions, the dependence of economically reasonable power on the load of the transformer in conventional units is obtained and given. The resulting dependence makes it possible to determine the optimal amount of power, taking into account the change in the load factor of the transformer, which is shown in the example