WEG AHF Active Harmonic Filter

The WEG AHF Active Harmonic Filter is a power electronics-based harmonic mitigation system rated from 30 A to 300 A per unit (expandable to 1,200 A via parallel units), designed to reduce total harmonic current distortion (THDI) from non-linear loads — variable frequency drives, UPS systems, switch-mode power supplies, and arc furnaces — to below 5% THD at the point of common coupling, meeting IEEE 519-2014 and IEC 61000-3-2/4 harmonic compatibility standards demanded by SEC for large industrial consumers and by NEOM's smart grid specifications for sustainable city infrastructure. Unlike passive LC harmonic filters that are tuned to specific harmonic orders and can cause resonance, the WEG AHF uses a real-time digital signal processor to continuously measure the harmonic current spectrum of the connected load and inject equal and opposite compensation currents that cancel harmonics across the 2nd through 50th order simultaneously.

The AHF's control system samples the load current at 40 kHz, processes the harmonic spectrum via a real-time FFT algorithm, and commands the IGBT-based compensation inverter to inject correction current within 250 μs — fast enough to track dynamically changing harmonic loads such as rolling mills, electric arc furnace heating cycles, and elevator drive groups. Beyond harmonic cancellation, the AHF simultaneously provides reactive power compensation (power factor correction) and load current balancing across the three phases — three functions from a single hardware platform, which in previous-generation installations required separate passive filters, capacitor banks, and load balancing reactors. The AHF operates at 380–480 V three-phase, 50/60 Hz, and is available in IP20 wall-mount and IP54 freestanding cabinet formats for installation flexibility across Saudi Arabia's electrical equipment rooms and outdoor utility buildings.

Saudi Arabia's industrial electricity infrastructure is under increasing harmonic stress as the proportion of non-linear loads — variable frequency drives in water pumping and HVAC, UPS systems in data centres, and LED lighting systems — grows in proportion to total consumption. SEC's technical specification GSTD-29-SDMS-032 limits THD at the point of common coupling to 5% for industrial consumers, and SEC enforcement of harmonic limits through power quality surveys and penalty provisions is increasing in parallel with the Kingdom's smart metering rollout. Data centres in Riyadh's King Abdullah Financial District, hospital electrical systems, ARAMCO offshore platform topsides with high VFD density, and NEOM's Cognitive City require active harmonic filtering to meet their building management system power quality specifications and SEC compliance obligations.

Razz Middle East provides complete AHF solutions for Saudi Arabia: power quality surveys using calibrated harmonic analysers, filter sizing per IEEE 519 methodology, AHF supply, installation, and commissioning, and post-installation power quality verification reports. Our team issues stamped power quality compliance reports for SEC regulatory submissions. The AHF is supplied with Modbus TCP/IP communication for integration into building management systems and industrial SCADA platforms. Contact Razz Middle East for a power quality survey and AHF sizing proposal with SAR investment and payback analysis.