When applying Active Harmonic Filters (AHFs) and Passive Harmonic Filters (PHFs) with generators. What concerns affect sizing and selection?
Most generators can handle capacitive kVAr of 20% of their kVA rating. If the capacitive kVAr of a PHF is above 20% of it’s kVA rating the generator’s Automatic Voltage Regulator (AVR) may not be able to control the output voltage which could cause the generator to trip off.
Applying AHFs on generators does not present a problem because an AHF is connected in parallel with the system supply and the AHF simply injects corrective currents into the system to eliminate harmonic currents and allow the system to meet IEEE 519 - 2014 recommendations. The capacitive kVAr required to keep the system’s power factor constant is continuously adjusted and is automatically kept well below the generators 20 to 25% reactive load capability.
When PHFs are applied on generators you must use one like the HPS Centurion P that is designed with capacitive reactance that is less than 20%. PHFs that have this level of capacitive reactance
