Electrical Engineering Fundamentals/Voltage Sources

A voltage source provides a potential difference.

There are several types of voltage sources. The most common ones are direct current (DC)  and alternating current (AC) .

A DC voltage source has constant voltage across its terminals. Examples of DC voltage sources are batteries and solar cells.

An AC voltage source has a voltage across its output the shape of sine wave with constant amplitude:


 * $$V(t) = V_p \sin(\omega t+\delta)\,$$

where
 * $$V(t)\,$$ is the voltage at time $$t$$
 * $$V_p\,$$ is the peak voltage
 * $$\omega\,$$ is the angular frequency
 * $$t\,$$ is the time
 * $$\delta\,$$ is some phase, which is often set to zero at $$t=0\,$$

An example of an AC voltage source is the AC generator.