Abstract

The paper presents thermal analysis and arc flash analysis taking care of protection relays coordination settings for electric motor drives connected to the electrical network. Power flow analysis is performed to check if there are any voltage and loading violation conditions in the system. Fault analysis is performed to check the short circuit values and compute arc flash energy dissipated at industrial busbars to eliminate damage to electrical equipment and electrical shocks and hazard to personnel. Computers enable the use of smart algorithms used by electrical engineers in providing accuracy of these actions. A fast and accurate procedure for proper incident arc flash energy computation and overcurrent relays coordination in distribution networks is presented. The paper presents the use of the Arc Flash module for arc flash energy computation during the short circuit on LV and HV busbars with soft motor starters. A sample case of one real network is presented which uses soft motor starters as well as the influence on arc flash energy in one transformer station supplying the industrial network in Bosnia and Herzegovina.

Keywords

arc flash, distribution network, electric motor drive, power flow, protection, short circuit, thermal analysis