AHF
ACTIVE FILTERS FOR HARMONICS
The all-in-one solution
for harmonic distortions
AHF
Active filters for harmonics
ACTIVE FILTERS FOR HARMONICS
AHF
The IREM active filters AHF series, also known as “active harmonic compensators”, eliminate harmonics through the generation of a reverse waveform that compensate for distortion.
The active filters of the AHF series ensure optimal suppression of harmonics regardless of the number of loads and their usage profile.
These filters, installed in parallel to the network, are sized to eliminate a specified amount of harmonic current from the system.
Typical applications include loads present in complex industrial plants; in melting, rolling mill and welding plants; in the oil and gas sector; in generation plants, in commercial and residential buildings, in tunnel ventilation systems and in data processing centers.

IREM PROPOSAL
The IREM active harmonic filter AHF series implements a process of compensation of the harmonic content: the harmonic current produced by the load is constantly monitored and an adaptive waveform is generated, that corresponds to the exact shape of the non-linear portion of the load current.
The AHF introduces this adaptive current into the load at the connection point with a reaction time of 50 μs and a response time of 5ms.
Unlike passive harmonic filters, these filters can provide harmonic mitigation in any load condition up to their nominal capacity.
The active harmonic filter works in parallel and compensates the harmonic content current, it can be chosen for applications consisting of a single or a multiple load of different types.
HARMONICS IN THE POWER SUPPLY



Voltage harmonics can disturb the control devices used in electronic systems, just think of the errors induced by zero displacement, or disturbances on control devices that use frequencies close to those of the harmonic components.
The electrodynamic forces produced by the instantaneous currents containing harmonics cause vibrations and acoustic disturbances, especially in electromagnetic devices (transformers, reactors, etc.). Furthermore, the presence of harmonics in the rotating fields can produce vibrations in the rotating machines, due to pulsating pairs.
The appliances that give rise to the harmonics are present both in the industrial sector and in the tertiary sector and lately also in the domestic sector: the harmonics are essentially due to nonlinear loads or those that give rise to current absorption with a trend different from the supply voltage.
The types of “distorting” load are: power electronics (rectifiers, inverters, etc.), but also welding machines, arc furnaces, speed variators, office equipment, monitors, even devices affected by saturation (transformers) can give rise to harmonics.
The alternators that supply non-linear loads must be derated due to the additional losses created by the harmonic currents.
VOLTAGE STABILISERS
Ministab - Sterostab
LINE CONDITIONERS
Ministatic - Steroguard
INTEGRATED POWER SUPPLIES
AI - AO
ISOLATION TRANSFORMERS
ITT - IT
PASSIVE FILTERS FOR HARMONICS
PHF - VTF
UNINTERRUPTIBLE POWER SYSTEMS
Minipower - Steropower
VOLTAGE OPTIMISERS
Ecostab - Ecobuck