Thyristor working as Arc Eliminator protecting electrical apparatus in low voltage power system

Thyristor functioning as Arc Eliminator (AE) is presented in this paper, in order to protect low voltage devices such as circuit breakers from damage caused by arc fault. The AE operating mechanism is firstly illustrated, AE is usually working as an active standalone device together with other existing switchgears. The reason of choosing thyristor as AE is mainly because of its fast speed and relatively lower cost in contrast with other solid state devices. One testing circuit was built up to study the arc eliminating performance of thyristor, with various arcing time and fault current amplitudes up to 2.7kA. The failure of eliminating the arc in an inductive circuit is also discussed. It is concluded that the thyristor functioning as EA is feasible and effective, to protect non-inductive devices from damages caused by arc fault.