In 2003, the mining company Antamina had problems with the overheating of the transformers that fed equipment with variable speed drives (VFD). Additionally there was burning of electronic equipment and constant disconnections of their harmonic filters.

To determine the causes of these disturbances and possible solutions, field measurements were made with equipment specialized for high harmonic resonance.

Based on these field measurements, coordination with the VFDs parent company and with the harmonic analysis performed with the ETAP Software, a high parallel resonance was detected in the VFD's electrical system.

With the help of the harmonics study conducted by EISAC and the timely collaboration of the VFD manufacturer, the problem was solved.

Other studies conducted for Minera Antamina:

2008 - Study of the Electrical System Expansion for harmonic filters