Panel Built Active Harmonic Filter

High harmonic distortion at Recycling plant.

Due to the proliferation of inverter loading at this site, concerns have been raised as to the amount of harmonic distortion being produced at this site and its potential effect on the other connected load as well as the wider effect on the MV supply to this site.

In order to determine the level of harmonic distortion present at this site as well as monitoring other power quality indices, a two week long power quality analysis was commissioned.

In addition to power quality indices, general power consumption data is presented in the form of active power (kW), reactive power (kVAr), apparent power (kVA) and operating power factor.


From the preceding results for this analysis it was clear that the load at this Recycling Centre operates with very high levels of harmonic distortion, high enough to distort the voltage to the point where the levels of voltage harmonic distortion exceed the G5/5 design recommendations


Despite the very high levels of harmonics on this supply, it will be possible to operate power factor correction at this site as it incorporates harmonic detuning reactors to prevent overload damage to power factor correction capacitors operating under such conditions.

Due to the very little additional space within the switchroom a stand alone AHF would not be possible, however the space within the distribution board allocated to power factor correction is generous and can be utilised to install harmonic filter modules that could be configured to remove the load harmonic currents and also correct the load operating power factor simultaneously.


With all these factors considered, a 300amp, 480volt P300-300/480 type Power Quality Filter System was installed inside of the existing LV panel along with 200kVAr of fully detuned Power Factor Correction.

All works and commissioning was carried out by 2 PFC Engineers over the course of 2 days with no interruption to sites load, with the majority of the equipment being pre-built and tested in our workshop prior to the install.