Mitigation of harmonics in oil field electric systems using a centralized medium voltage filter

Variable frequency drives are increasingly being used in oil fields to operate pump jacks. Significant harmonic distortions are expected for such applications. Two schemes have been proposed to mitigate the harmonic distortions. One scheme involves a centralized medium voltage filter and the other distributed low-voltage filters. This paper presents the results on the application of MV filters. Performance characteristics, application issues, and economical implications of the MV filtering scheme are determined. The results show that MV filters are an attractive option for harmonic mitigation in oil field systems with a large number of variable frequency drives. The most efficient filter type is the one consisting of a large 11th filter and small 5th and 7th filters.