The effects of harmonics on loads

The following two types of effects appear in the main equipment: immediate or short-term effects and long-term effects.

Immediate or short-term effects:

1. Unwanted tripping of protection devices,
2. Induced interference from LV current systems (remote control, telecommunications),
3. Abnormal vibrations and noise,
4. Damage due to capacitor thermal overload,
5. Faulty operation of non-linear loads.

Long-term effects associated with current overload that causes overheating and premature deterioration of the equipment.

Affected devices and effects:

• Power capacitors:

1. additional losses and overheating,
2. fewer possibilities of use at full load,
3. vibrations and mechanical wear,
4. acoustic disComfort.

• Motors:

1. additional losses and overheating,
2. fewer possibilities of use at full load,
3. vibrations and mechanical wear,
4. acoustic disComfort.

• Transformers:

1. additional losses and overheating,
2. mechanical vibrations,
3. acoustic disComfort.
4. automatic switch:
5. unwanted tripping due to the peak current being exceeded.

• Cables:

1. Additional dielectric and chemical losses, especially on the neutral, when 3rd order harmonics are present,
2. overheating.

• Computers:

Functional disruptions causing data losses or faulty operation of control equipment.

• Power electronics:

Waveform interference: switching, synchronisation, etc.

Summary table of effects, causes and consequences of harmonics

ZDDQ Products

Low voltage: Active Hamorminc Filter

Medium Voltage: Statcom