Active Harmonic Filters: The Smart Way to Fix Harmonic Distortion

Active Harmonic Filters: The Smart Way to Fix Harmonic Distortion

Harmonic distortion is one of those hidden issues that can quietly wreak havoc on your electrical system. It’s responsible for things like overheated transformers, motor failures, and unexpected equipment shutdowns. If your facility uses a lot of variable-speed drives or other nonlinear loads, chances are you’ve seen the effects firsthand.

That’s where Active Harmonic Filters (AHFs) come in. Unlike traditional passive filters, AHFs continuously monitor and correct harmonics in real time, keeping your power system clean, stable, and efficient.

What Causes Harmonic Distortion?

Whenever your equipment draws current in short bursts instead of smooth sine waves—think VFDs, welding machines, or UPS systems—it creates harmonics. These are unwanted frequency components that ride on your power line and disrupt normal operation.

The consequences?

• Overheating: Even a small increase in Total Harmonic Distortion (THD) can raise transformer and motor temperatures by up to 30%.

• Energy Waste: Harmonics cause current to circulate unnecessarily, turning energy into heat instead of useful work.

• Equipment Malfunction: Protection devices may trip unexpectedly, or worse, fail to trip when needed.

Why Choose Active Harmonic Filters?

AHFs are designed to adapt on the fly. They use real-time sensing to detect harmonic distortion and inject equal-but-opposite currents to cancel it out—kind of like noise-cancelling headphones for your power system.

Compared to passive filters, AHFs offer:

• Real-time harmonic correction (from the 2nd to the 50th order and beyond)

• Improved power factor without the need for bulky capacitor banks

• Smaller footprint with modular, space-saving designs

• Better stability across a wide range of load conditions

Meet YT Electric: Your AHF Partner

YT Electric is one of China’s most experienced AHF manufacturers, with over 15 years in the field. Headquartered in Shanghai, subsidiary of listed company stock code 300222, we’ve shipped more than 60,000 AHF and SVG units to over 50 countries.

Our product lineup includes:

• Rack and wall-mounted modules from 15 A to 200 A

• Cabinet systems ranging from 50 A to 800 A

All equipped with adaptive FFT algorithms, dual current transformers, and IGBT inverter cores

We’re ISO9001, CE, and CQC certified, and all our products are backed by full type-test reports.

Who Needs AHFs?

1. Industrial Plants

Factories using lots of VFDs—like textile mills or steel plants—benefit from THD reduction below 5%, helping them stay compliant with IEEE 519 and avoid utility penalties.

2. Data Centers & Hospitals

Sensitive electronics need clean power. AHFs help eliminate power glitches that could lead to downtime or damage.

3. Renewable Energy Systems

Solar and wind inverters can generate harmonics. AHFs smooth out the current before it hits the grid, improving system performance.

How to Choose the Right AHF

Before buying, it’s important to:

• Run a harmonic analysis to find out which harmonic orders are present

• Size the unit based on peak harmonic current or reactive power (kVAr)

• Decide on two-level or three-level topology (three-level offers better waveform quality)

• Install the AHF at the PCC (Point of Common Coupling) or right near the harmonic source

Contact an Expert

Active Harmonic Filters are no longer just an option—they're essential for any facility dealing with complex loads and rising power quality demands. Whether you're trying to avoid penalties, reduce maintenance costs, or simply keep your operations running smoothly, AHFs provide a future-ready solution.

And with YT Electric’s proven track record, global reach, and reliable technology, you’ve got a partner you can count on to power your success.