Modelling of Deterioration of Electrical Insulation of Low Voltage Power Lines Seaports

Abstract

The paper deals with the problem of analysis of time between failures (wear) of electrical insulation in conditions of lack and inaccuracy of data on the state of the object. The study of the specifics of the aging of such a system element of the sea port power supply as the isolation of power cable lines shows its importance in influencing the reliability of the port power supply. Marine intra port electrical network has its own specifics - firstly, it is a low-voltage network and high-ampere, in which the role of partial charges is minimal, secondly, in marine low-voltage power lines there are areas of increased sensitivity to the environment associated with the output of the power line (cable) from trenches to current collectors and contact columns with stripping insulation, which begins to contact with the environment, thirdly, in connection with the above, the humidity plays a destructive role, acting together with increased temperature. In the process of building a model of operating time before insulation deterioration, factors that are measurable with the help of devices are taken into account, and they also significantly characterize the long-term effect on insulation deterioration and lead to a state of failure. This article develops a mathematical model based on inaccurate data with estimated limits of inaccuracy. To solve the problem, computer simulation using the membership functions of fuzzy sets is proposed. Using the developed software in Mathcad obtained the numerical results of time to failure.