An active filter is basically an inverter based harmonic current source that measures the magnitude and phase of the load current harmonics.
The active filter control synthesises the load harmonic currents but phase shifts them by 180°. This harmonic anti-phase current is injected into the system and combines with the load current to create a supply current that has a much-reduced level of harmonic distortion.
The principal of operation is shown graphically in the illustration.
Following on from an harmonics analysis of the sites supply, Active Harmonic Filtration (AHFs) can be implemented to help minimise the distortion.
They work by putting harmonics back into the electrical system in an equal and opposite measure to the existing harmonics. AHFs can be designed to target all harmonics or just the harmonics that are causing a specific issue to site.
As part of the load and harmonic analysis report we can provide a complete, no-obligation quotation for installing Active Harmonic Filtration as required.
If you wish to arrange a week long load and harmonic analysis please feel free to contact us.
PFC Engineering Ltd has partnered with Active Filter Manufacture Comsys to bring you state-of-the-art Harmonic Filtration solutions.
Founded in 2001 by a small group of Swedish engineers, today Comsys is a well-established and rapidly growing company with Active Dynamic Filters being their number one innovation since the start.
Combined with PFC Engineerings’ 48+ years in the Power Quality industry we aim to provide sustainable energy solutions custom-made for your site’s requirements, saving you money and helping to reduce your site’s Harmonic Distortion levels.
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