Armonicos

 
System Harmonic Guidelines

Steelman Industries recognizes the need for addressing harmonics in an electrical system that will soon be fitted with power factor correction capacitors.To conclusively determine whether or not a system needs filters along with the capacitors, a harmonic study must be done. The following summary of IEEE 519 1992, is a good start tounderstanding harmonics in an electrical system as they relate to applying power factor correction capacitors. In order to obtain the warranty (page 16), a harmonic study with the followingreadings must be provided to Steelman Industries at the time of order.

Harmonic Limits in Electric Power Systems (IEEE 519 1992)
Harmonic limitations have been established by IEEE 519 1992 forthe following reasons:
• To limit the damage to power factor correction capacitors and harmonic filter systems caused by excessive harmonics.
• To prevent series or parallelresonance in the electrical system.
• To keep the level of harmonics at the PCC (Point of Common Coupling) from being excessive and distorting the system voltage and damaging otherequipment on the system.
The PCC is defined as the electrical connecting point or interface between the utility distribution system and the customer's electrical distribution system.
Theharmonic voltage limitations set forth by IEEE 519 1992 are:
• Maximum Individual Frequency Voltage Harmonic: 3%
• Total Harmonic Distortion of the Voltage: 5%
The harmonic currentlimitations are defined in the following table:
|Maximum Harmonic Current Distortion in Percent of IL |
|120 Volt through 69 KV|
|Individual Harmonic Order (Odd Harmonics) |
|ISC/IL |h