The Dynamic Harmonic Filter (DHF) with smart sensing is an efficient and cost-effective solution to filter harmonics on both sides of the voltage bus.
The filter reduces harmonic distortion by selectively absorbing the harmonic currents present in the system. It uses advanced sensing technology to constantly monitor the system and adjust its performance in real-time, ensuring optimal performance at all times.
The DHF is voltage controlled, therefore no current transformers are needed. The DHF removes the need for detailed site harmonic measurements and complex calculations.
The DHF corrects harmonics 5th, 7th and 11th, whether they are created by equipment within the customer’s premises and/or from those created elsewhere and transmitted via the electrical utility supply.
The DHF smart sensing capability of this filter leads to improved power quality, reduced energy consumption, and longer equipment life compared to traditional filters. This is because the filter adjusts its performance based on changing load conditions, ensuring optimal efficiency at all times.
The Omniverter DHF has three unique features to consider when choosing an appropriate solution:
A harmonic distortion is a form of pollution in an electrical system. A harmonic voltage or current waveform is a sinusoidal wave whose frequency is an integer multiple of the fundamental frequency. For example, the 3rd order harmonic frequency for a 60Hz system is 180Hz, 5th is 300Hz, 11th is 660Hz, etc.The waveform distortion is expressed in Total Harmonic Distortion as a percentage. THD or THDi is a measurement of the harmonic distortion present and is defined as the ratio of the sum of the power of all the harmonic components to the power of the fundamental frequency.
Harmonic generation are generally found in saturated and power electronic devices. For example, a transformer and a motor create harmonics when over-fluxed or saturated. Power electronics (non-linearloads) also produce harmonic frequencies, loads like rectifiers or variable frequency drives.
The following scenarios are some of the failures that are common when the THD is above the recommended levels:
Harmonics can be produced in a plant and/or it may be transmitted upstream from the utility supply. In practice, it is difficult to determine who is responsible for the harmonic distortion as it depends both on the utility supply (impedance) and the customer (load current).
Therefore, detailed analysis is required to determine the source of distortion. Power Quality Analyzers installed permanently are advisable to measure and monitor the THD levels.