Features of Forecasting Reliability of 6—10 kV Overhead Electric Lines According to Statistics of Their Failures and Reconditionings

This work is aimed at forecasting justification of the failure time of the 6—10 kV overhead electric lines (OEL) during the normalized period in its operation based on comparison with the statistics of failures and reconditionings on the previous intervals with the use of the OEL availability function, statistical availability coefficient, normalized forecasting interval and the accepted values of the availability coefficient on the forecasting interval. To achieve the goal set the OEL is described as an object of a multiple action, its failure and reconditioning flows are accepted as the simplest Poisson, and for the theoretical analysis of the variation character in the availability coefficient, the probability theory methods along with a mass service were used. The most significant result is justification of the use for the forecasting of the OEL failure time of a new convenient exponential expression of its availability function on the normalized period of time being forecasted. Unlike the accepted in the theory of reliability the availability function with two parameters T and Tr.av (average times of work and reconditionings), the proposed expression uses one parameter of distribution (virtual non-failure operating time). The significance of the results obtained consists in that controlling the dynamics of the variation in the statistical coefficient of availability of the OEL on the previous time intervals makes it possible to forecast its failure time during the forthcoming normalized periods of operation.