Waveform Distortions :
If it is assumed that all of the elements in the power system are linear, the current and voltages will be sinusoidal in the calculations related to the generation, transmission and distribution of electrical energy. The fact that current and voltage waveforms are not sinusoidal at a nominal frequency is defined as waveform disturbance.

5 general waveform distortion.

• DC component
  Harmonics
  Intermediate harmonics
  Notch formation
  Noise
   

GüThe presence of a direct current or a true voltage in the power system is referred to as the DC component. The effect of the natural magnetic field of the earth on the very long transmission lines or the half wave rectifiers are the main reasons for the DC component. The presence of direct current in the system has losses such as increase in transformer saturation and temperature, insulation problems.
The sinusoidal current and voltage waveforms of the frequency (fundamental frequency) of the frequency determined for the operation of the energy system are called harmonics. Combined with the waveform of the fundamental frequency, it causes waveform distortion. The reason for the general occurrence of harmonics is the presence of power electronic elements with non-linear characteristics in the system.
Generally, there are no components in the network that are merely the basic frequency. Voltage and current values ​​containing frequency components of the fundamental frequency of the network are not exact. The araharmonics can be seen at all voltage levels. Arc furnaces, induction furnaces and static frequency inverters, as well as basic frequency synchronous equipment araharmonik formation causes.
Another distortion in the waveform is the notch formation. AC-DC inverters can be defined as periodic voltage distortions during commutation. Short circuit occurs in the system and the voltage decreases momentarily. This situation is very high frequency and periodic because it is not classified as harmonic or transient events.
Another distortion often seen in power systems is noise. They are unwanted electrical signals with a frequency range of less than 200kHz. The amplitude is usually less than 1% of the voltage. It can damage very sensitive electronics such as microprocessors and microcontrollers. Power electronics and control circuits, arc-making equipment and switching power supplies are the main sources of noise. Improper grounding can also increase the noise effect. Noise can be eliminated by using a filter or insulation transformer.