Arc Flash Assessment and Mitigation in a 33/11kV Primary Distribution Network

Arcing occurs when there is separation of energized contacts of switchgears which occurs when breakers are tripped due to a fault, thus, an arc flash is a spark of electrical current which leaves its intended path and travels through air from one conductor to another.This paper presents an approach for determining the nature and frequency of arcs in electrical power systems as well as adequate measures required to mitigate the effect of the arc initiated.This paper presents an approach for arc flash assessment and mitigation in a 33/11kV power system which was modelled and analyzed by Electrical Transient Analyzer Program (ETAP) software.A load flow study was carried out using Newton Raphson's method to verify the existing operating condition of equipment in the power system.Furthermore, a short-circuit analysis was performed to aid proper selection and sizing circuit breakers for relay coordination.Finally, an arc flash analysis was performed which determined the nature and frequency of the arc as well as methods required to mitigate its effect.