Active Harmonic Filter

One of implementation harmonic mitigation is using harmonic filter (AHF). Method of harmonic mitigation consist of two filtering: passive filter and active filter. Passive Harmonic Filters eliminate or mitigate harmonics much the same way that Active Harmonic Filters do. Passive Harmonic Filters filter the current wave through an input reactor, output reactor, shunt reactor and capacitor. They are a simpler solution for individual items of equipment but are limited to the individual and stable loads only. Passive filters can be limited when it comes to their effectiveness and capacity. Large installations are likely to require Active Harmonic Filters as they are able to work with numerous variable speed drives. If an installation contains many non-linear loads, a Passive Harmonic Filter will not be able to effectively perform. Active Harmonic Filters are used to eliminate, or at least mitigate, harmonics experienced from power received. he electricity which is delivered to a property is not necessarily ‘clean’ and therefore properties can experience harmonics. Harmonic currents lead to power which is polluted enough to cause failures within an installation and it also takes up capacity within the electrical system. Active Harmonic Filters should be installed to minimize harmonics and therefore optimize the power supply. An Active Harmonic Filter includes a series of transistors and capacitors to clean the current sinewave through inverse currents which will eliminate the majority of undesired harmonic components. Voltage fluctuations and harmonics cause grid disturbances and this can damage equipment, cause power surges and lead to overheating in addition to increasing energy bills. By installing an Active Harmonic Filter, a property is also helping to clean up Australia’s electrical grid supply, benefitting all users and the planet. Active Harmonic Filters are larger than Passive Harmonic Filters. While we recognise that some installations are limited by space, Active Harmonic Filters are able to provide a superior level of power quality improvement. Active Harmonic Filters will not overload when the active filter limit is reached, while a Passive Harmonic Filter may be at risk of doing so. Additionally, if an Active Harmonic Filter is rendered incapacitated, the motors for which it is optimising power will not be affected. This is due to the fact that the current itself does not run through the filter. For installations where constant output is key, we recommend Active Harmonic Filters. While the initial cost will be higher, an Active Harmonic Filter will, in the long run, be more effective when it comes to maintaining a business’ bottom line by guaranteeing ongoing output and reducing energy costs.

Active Harmonics Filter Panel
Active Harmonics Filter Panel

Above Figure is one of our project for active harmonic filter implementation in Main Distribution Panel of Low Voltage. Installed parallel with main busbar and can be act for power factor correction. Function of capacitor ban can be covered by this active harmonic filter. Compensation time faster than capacitor bank.

Single Line Diagram of Active Harmonic Filter at Main Distribution Panel