Nonlinear loads
Can someone please help me understand what exactly is a nonlinear load? I guess it has to do something with the noise that is encountered in electronic equipment such as computers, electronic ballasts, etc. most loads i think are linear. please clarify.
Best Answers

AC electrical loads are classified as linear and nonlinear. Here, linear load means the current is proportional to voltage (Ohm's law) at any time and the relationship between current and voltage are sinusoidal. Examples of linear load are ideal resistors, transformers etc.
On the other hand, in case of nonlinear loads, the current is not proportional to voltage. The current fluctuates depending upon the alternating load impedance. Here, the impedance changes with the applied voltage. The current waveform in nonlinear loads contain different components that are multiples of fundamental frequency of the system. These components are called harmonics.
Examples of nonlinear loads are computers, electronic ballasts, refrigerators, variable speed drives, rectifiers etc.

linear loads are those loads which draw current in proportional to the voltage increase.A load where the wave shape of the steadystate current will follow the wave shape of the applied voltage.Examples of Linear Loads: Power Factor Improvement Capacitors, Incandescent Lamps, Heaters.
Nonlinear Electrical Load is a load where the wave shape of the steadystate current does not follow the wave shape of the applied voltage.Examples for NonLinear Loads: Electronic equipment, electronic/electricdischarge lighting, adjustablespeed drive systems, and similar equipment.