# Harmonics and its effects in AC power system

In AC (alternating current) circuits, harmonics are additional frequency components of the voltage or current waveform that are integer multiples of the fundamental frequency. For example, if the fundamental frequency of a circuit is 50 Hz, the second harmonic would be 100 Hz, the third harmonic would be 150 Hz, and so on.

Harmonics can be caused by nonlinear loads in a circuit, such as electronic devices that draw current in pulses rather than continuously. These loads can introduce distortion into the voltage or current waveform, causing harmonics to appear. Harmonics can also be introduced by certain types of AC power sources, such as generators or inverters, that generate non-sinusoidal waveforms.

Harmonics can have a number of effects on AC circuits. For example, they can cause increased power losses, reduced power factor, and decreased system efficiency. They can also lead to overheating of equipment, electromagnetic interference, and reduced equipment lifespan.

## Harmonic distortion and its effects

Harmonic distortion in an AC sinusoidal waveform occurs when the waveform is distorted due to the presence of harmonics. It can occur in AC power systems due to various causes, such as non-linear loads and improperly designed electrical systems.

The effects of harmonic distortion in AC power systems can be significant. Some of the effects include:

1. Increased current: The presence of harmonics in the waveform can cause the current to increase, even if the load is constant. This increased current can lead to overheating of equipment and reduced equipment lifespan.
2. Reduced power factor: Harmonic distortion can lead to a reduction in power factor, which is a measure of how efficiently the electrical system is using power. A low power factor can lead to increased energy costs and reduced system efficiency.
3. Voltage distortion: The presence of harmonics can cause voltage distortion, which can affect the performance of sensitive electronic equipment. Voltage distortion can also cause flicker in lighting systems.
4. Overheating: Harmonic distortion can cause overheating of equipment, which can lead to equipment failure and reduced lifespan.
5. Electromagnetic interference: Harmonic distortion can cause electromagnetic interference, which can affect the performance of nearby electronic equipment.

To mitigate the effects of harmonic distortion, it may be necessary to use filters, transformers, or other devices to reduce the harmonic content of the voltage or current waveform. Additionally, proper system design and maintenance can help to minimize harmonic distortion in AC power systems.