Impact of the compensation equipments and Electric Arc Furnance (EAF) in “Zeljezara” Niksic to Power Quality in Transmission System

Preliminary determination of the impact of the "Electric Arc Furnance in “Zeljezara” Niksic to Power Quality in Transmission System, according to the international standards, was carried out in a short period of operation of the furnace of 10 days in April 2013. Measuring of the power quality is done on the transformer T3 in SS 110/35 kV Niksic, which supplies electric arc furnace in "Zeljezara".

The main recommendation and the final conclusion of the previous study (performed in 2013), was to install the compensation device that will improve low power factor of arc furnaces in “Zeljezara” Niksic and bring it within permitted walues cosφ≥0.95, according to the "Rules for the electrical transmission system operation " of Montenegro.

This study determines an impact of the compensation devices (SVC) at 35 kV medium-voltage busbars in steel smelter “Zeljezara” (which is supplied from transformer T3) to power quality and voltage in transmission system of Montenegro. Specifically, 110 kV substation Niksic is concerned and the comparisons are to be done according to latest standards in periods when steel smelter is energized and fully operative, or it is not operative. According to recommendations, at the end of 2014 for a period of one week, from 6 to 12 October, a control measurement was performed. The measurement was carrie out at the same point of 110 kV busburs in SS Niksic, where the transformer T3 is supplied.

Simultaneously, in the same period, a measurement by another device of the same type, was performed (connected to the 110 kV voltage busbars in SS Niksic) on the feeder of transformer T4, which supplies not operative work of steel smelter “Zeljezara". Impact of the new compensation devices on the quality of electricity shall be made by comparing the results of the previous measurement from 2013.

Type of services provided:

• Measurement and effects of EAf and compensation devices (SVC) in steel smelter “Željezara” Niksic regarding power quality in SS Niksic;
• Defining the list of power quality parameters to be measured;
• Consumer’s active and reactive power analyses;
• Power factor analyses;
• Voltage quality at 110 kV level in SS Niksic;
• Voltage unbalance level;
• Short and long term flicker indexes;
• Individual and total voltage harmonic distortion