Experience with Live Working in utility Elektro Gorenjska

In the last several years, Slovenian power distribution companies have been successfully carrying out preventive maintenance works within the framework of live working (LW) on both low voltage (LV) and medium voltage (MV). The utility company Elektro Gorenjska (EG) supported idea of implementation LW in Slovenia when activities started in 2006. At the end of 2010, the EG management decided to accelerate the process of introducing LW on low voltage (LV) and in 2013 also on medium voltage (MV) – cleaning of MV transformer station. In 2014, the utility company EG started the systematic planning of MV transformer station revisions with the LW method. This paper presents the multi-year experiences with carrying out LW on MV. It shows the effects on the indicators of power supply reliability in the period 2014–2021 and the advantages of carrying out maintenance works with the LW method on MV in the utility company EG and experiences with effects of LW on the improvement of indicators SAIDI (System Average Interruption Duration Index) and SAIFI (System Average Interruption Frequency Index).