WEFTEC 2000: Universal Harmonic Filter

This patent pending UHF is an easy to apply, passive harmonic filter capable of reducing Variable Speed Drive (VSD) harmonics by up to 10x. The device consists of a new inductor combined with a relatively small capacitor bank. Its design achieves cancellation of all the major harmonic currents generated by VSDs and other similar 3-ph, 6-pulse rectifier loads, resulting in THID of <8% and often as low as 5%. Additional features include:

•Meets IEEE 519 standard for both current and voltage distortion
•Power factor 0.98 lagging to 0.95 leading over the normal operating range
•Compatible with engine generators since capacitive reactance is <15% of rated kVA even under light loads
•Does not resonate with other power system components
•Suppresses overvoltages caused by capacitor switching and other fast changing loads
•Saves energy by reducing upstream harmonic losses while operating at >99% efficiency
•Reduces DC bus ripple and increases ride-through capability of the load

MIRUS International, Inc., 801 Sheppard Ave. W., Toronto, ON M3H 2T3. Tel: 416-633-2600; Fax: 416-633-2613.