Reactive power compensation in thermal ore production

The paper deals with the issues of reactive power compensation during the operation of arc steelsmelting furnaces (EAF) in ore-thermal production. The values of voltage non-sinusoidality coefficients for various EAF melting modes are given. Comprehensive studies were carried out, presenting an analysis of the effectiveness of reducing voltage distortion by power filters, which can be presented without a dynamic group, and comparing the data obtained with the results of using filters of the 3rd and 5th harmonics, which are part of reactive power compensators. The results of studies of the distortion of the shape of the voltage curve during the operation of the EAF indicate that in the absence of dynamic compensation devices, the requirements of the state standard for the quality of electricity are provided without turning on filters. Filters are needed to limit consumption while eliminating the possibility of resonance in parallelconnected capacitors and source-coupled inductive reactances. According to the results of the performed calculations, it can be seen that by installing the 3rd harmonic filter on the ZRU-35 kV buses, significant results were achieved, namely, the voltage swings were minimized (up to 0.78%) and the issue of reactive power compensation was simultaneously resolved ($\cos\varphi$ = 0.95) at the lowest unit cost.