Harmonic Distortion from Variable Frequency Drives

cancelled with single transformer • VFD harmonics (5th, 7th, etc.) are cancelled using pairs of transformers. – Delta -> Wye transformers have 30° phase shift – HMT’s have various degrees of phase shifting depending on manufacturer - 0°, +15°, 15°, etc. Phase Shifting – Harmonic Mitigating Transformers (HMT)

  Transformers