Harmonics in an electric power system are a result of non-linear electric loads such as Variable speed drives, UPS, Furnaces & lighting . Harmonic frequencies in the network are frequent cause of power quality problems.

Impact of Harmonics

• Overload of cables, components , capacitors, transformers causes additional losses, decrease of lifetime, increased maintenance costs.
• The current distortion (THDi) through the system impedance can generate voltage distortion (THDu) which can cause malfunction or failure of many types of equipment being supplied from the same power line.
• Excessive currents in the neutral conductor.
• Nuisance tripping of Circuit Breakers.
• Lowering power factor, increase of reactive power consumption.

Sufferers

Power consumers, network operators , power industry

Solution

Harmonics can be Filtered through a combination of reactors and capacitors (Passive Filters) or by injecting exact opposite of the harmonics detected through active Filter into the network.