Active & Passive Harmoinc Filter

Modern networks problems, harmonics

In recent years, electronic devices such as computers, speed drivers for production control systems, air-conditioning, lifts with the soft stop, pumps with soft start, etc., are increasingly used.

Their correct functioning brings various benefits on an industrial and private level but on the other hand it causes serious problems in terms of energy supplies and efficiency.

This is because the power electronic devices equipped with rectifiers, modulators etc., distort the wave shape of the current for the correct operation, creating the harmonics, which represents the deviation between the ideal sinusoidal waveform the network voltage or the load current should have, and what really it is.

Reduction of harmonic currents can report quantifiable benefits in terms of overall installation cost, energy bill reduction and protection against process interruptions and equipment faults.

Types of loads that generate harmonics:

• Solar and wind inverters

• Air-conditioning systems

• Pumping systems

• Variable speed drivers, converters…

• Cooling chambers

• PLCs

• Electronic light ballasts (LED)

• Personal computers (PC’s)