Zag Grounding Bank Understanding Zig

Harmonic Distortion from Variable Frequency Drives

• Special wound transformers (typically zig-zag) that use phase shifting to cancel harmonics • Application depends on the targeted harmonics • Triplen harmonics (3rd, 9th, etc.) can be cancelled with single transformer • VFD harmonics (5th, 7th, etc.) are cancelled using pairs of transformers. – Delta -> Wye transformers have 30 ...