Arc-Flash Risk Level Calculations based on Computer Simulations and Measures to Avoid Hazards

Safety of the electricity distribution personnel during maintenance, repair, test, and measurement in the distribution areas is in the thread of the energy of the electric arcs due to potential short circuit faults. Unfortunately, every year people are injured, burned or killed because of these accidents. In parallel with population increase at metropolitan cities, short circuit levels of the power system, and thereby arc-flash risk levels, increase. This study provides a general overview of the arc-flash analysis and measures to avoid hazards. Arc flash hazard levels are calculated based on computer simulations which are performed by DigSilent PowerFactory power system analysis software. IEEE 1584 and NFPA 70 standards are considered in assessing the simulation results. Temporary change of relay coordination technique (temporary maintenance switching) is investigated as a solution for the substations in which arc-flash hazard level is beyond acceptable levels. Numerical analysis are performed for several medium and low voltage substations in the territory of EnerjiSA Distribution Companies in Turkey.