Online Monitoring System for OLTC of Fum ace Transformer

The authors consider the problems of developing and deploying online systems for monitoring the technical condition of on-load tap changers (OLTCs) of electric-arc furnaces (EAFs). The problems are addressed using individual transformer OLTCs of two high-power furnaces (EAF-1 and EAF -2) with an output of 180 tons. The authors study the operating processes of EAFs that lead to multiple OL TC switching during the electric-arc melting of steel. The authors stress the relevance of developing an operative control system for OL TC conditions. The deployed TDMS-type (Transformer Diagnostics Monitor Special) online system for monitoring the technical condition of EAFs was reviewed including the developed OL TC monitoring units. The authors developed the diagnostic parameters and OL TC condition control methods implemented in the TDMS system. The main methods include switching number control, indirect control of moving part conditions, and vibration control. The authors provide the oscillograms of diagnostic parameters including vibration acceleration and the OL TC switching current. A conclusion is made on the technical efficiency of the system deployment.