Harmonic Mitigating Transformers

Harmonic Mitigating Transformers (HMTs) are designed to enhance power quality and system reliability in electrical networks supplying non-linear loads such as variable frequency drives (VFDs), UPS systems, and other electronic equipment. By effectively reducing current and voltage distortion, these transformers help maintain balanced loading, minimize neutral currents, and extend the life of connected equipment.

These HMTs utilize two advanced design principles to achieve superior harmonic performance:

Zero Sequence Flux Cancellation:

The secondary windings are specially configured so that zero sequence fluxes — primarily the 3rd, 9th, and 15th current harmonics — cancel out internally without being drawn from or circulating in the primary delta winding. This flux cancellation provides a low-impedance path for zero-sequence harmonics, significantly reducing voltage distortion and transformer losses.

Phase Shifting:

Non-triplen harmonics such as the 5th, 7th, 11th, and 13th are mitigated through phase-shifting techniques on the secondary side. Depending on the selected arrangement (single, dual, or triple output), specific harmonic currents are effectively cancelled before they couple into the primary winding.

The result is cleaner power, higher efficiency, and lower operating temperatures — ensuring stable, reliable performance in harmonic-rich environments.