HARMONIC FILTERING SOLUTIONS

The increasing use of modern power electronic apparatus (drives, uninterruptible power supplies, etc.) produces nonlinear current and thus loads the network with harmonics. The capacitance of the power capacitor forms a resonant circuit in conjunction with the feeding transformer. Experience shows that the self-resonant frequency of this circuit is typically between 250 and 500 Hz, i.e. in the region of the 5th and 7th harmonics. Typical loads requiring harmonic filtering include 6 pulse drives (AC / DC), 3 phase UPS, frequency converters

Active Harmonic Filters
With L&T’s active harmonic filters, reduce your THD levels to within IEEE/CEA limits. These filters are IGBT-based power converters. This filter injects negative of the harmonic current resulting in practically no harmonic distortion. Phase balancing and power factor correction is also achieved.

Features:
30-600 A Active filter in 3 phase 3 wire/4wireStand-alone & modular unitsResponse time less than 1 ms/li>Easy diagnosis of fault conditions with alarmsEasy configuration & parameter monitoring with LCD touch screen HMI
Reactors – Harmonic Filtering
Detuned harmonic filters are the series combination of a reactor and power capacitor. This filter offers higher impedance for high frequency harmonics. This prevents harmonic resonance and amplification.

Features:
Available as 7% (189 Hz) & 14% (133 Hz) detuned filtersCopper & Aluminium wound reactorsVery low operating losses – 3 to 5 W / kVArHigh linearity – 1.8 times the rated currentLow noiseAuto-thermal cut-off