Digital substation reliability evaluation

The paper considers the means of boosting the reliability of digital substations, taking into account the intensifying digitalization of the Russian Federation economy, power supply and industry. The paper analyses the existing directives and methodology in sphere of calculating and evaluating the reliability indicators for digital substation technology. The topological scheme and the reliability equivalent circuit of substation switchgear 220 kV are compiled as an example for the Rudnaya Substation, located in the Far East of Russia and currently being converted to its digital version. A numerical estimation of the survival function for the main equipment of the 220 kV switchgear is given based the classical theory of reliability. The digital substation blocks with low reliability indicators are identified. The large number of secondary circuits which using for digital measuring and connecting interface devices are revealed as a negative factor for the reliability indexes. The means for required reliability level maintaining for the digital substation are considered.