What does harmonic distortion in an electrical system refer to?

Harmonic distortion in an electrical system specifically refers to the presence of frequencies in the voltage or current waveforms that are integer multiples of the fundamental frequency. In an ideal electrical system, the waveform is a pure sine wave. However, when there are non-linear loads present, such as computers or variable speed drives, they can distort this sine wave, leading to the generation of harmonics. These harmonics deviate from the pure sine wave shape and can create various issues in the system, such as overheating, increased losses, and interference with other equipment.

Recognizing harmonic distortion is essential for maintaining the efficiency and reliability of electrical systems. By understanding that it represents a deviation from a pure sine wave, engineers and technicians can diagnose and correct issues arising from these distortions, thereby enhancing overall system performance.