Correction of methods for calculating the single-phase short circuit current in a rural 0.4 kv electric grid

Abstract

The relevance of the study lies in the consideration and correction of the results of calculations of the single-phase short circuit current in a rural 0.4 kV electric network obtained using existing physical, computer and mathematical methods that give different results. Purpose. Development of correction coefficients for different methods of calculating the single-phase short circuit current in a rural 0.4 kV electrical network. Materials and research methods. During the calculations of the single-phase short circuit current in the 0.4 kV rural electric grid, using different methods, general initial conditions were set: power was supplied from a TM-250 transformer and using A-35 wire. Results. It was revealed that the error between the results obtained using different methods reaches 35.9%. In the work, correction coefficients with values from 0.93 to 1.47 relative units were proposed in order to increase the reliability of calculations. These coefficients made it possible to increase the reliability of the considered methods for determining the current of a single-phase short circuit in a rural 0.4 kV electrical network by 2.9-6.1 times compared with the initial values.