Effects of harmonics

Harmonic currents increase the r.m.s. current in electrical systems and deteriorate the supply voltage quality. They stress the electrical network and potentially damage equipment. They may disrupt normal operation of devices and increase operating costs.

1. What is harmonics and its effects?
2. What are the common effects of harmonics?
3. What are the causes and effects of harmonics?
4. What are some of the effects of harmonics on conductors?

What is harmonics and its effects?

Harmonics are defined as the content of signal whose frequency is an integral multiple of the system frequency of the fundamental. Typical harmonics for a 50 Hz system (fundamental frequency) are the 5th (250 Hz), 7th (350 Hz), 9th (450 Hz).

What are the common effects of harmonics?

Simply stated, there are two basic concerns: Current harmonics cause unwanted current and overheating. Voltage harmonics cause misoperation of equipment.

What are the causes and effects of harmonics?

Harmonics are the result of nonlinear loads that convert AC line voltage to DC. Harmonics flow into the electrical system because of nonlinear electronic switching devices, such as variable frequency drives (VFDs), computer power supplies and energy-efficient lighting.

What are some of the effects of harmonics on conductors?

The primary effect of harmonics on power cables is the additional heating due to increase in the I²R losses. This can be attributed to the two phenomena known as skin effect and proximity effect, both of which vary as a function of frequency as well as conductor size and spacing.