Electrical Engineering Fundamentals/Voltage Sources

A voltage source provides a potential difference.

A DC voltage source with constant voltage connected to a resistor

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:


is the voltage at time
is the peak voltage
is the angular frequency
is the time
is some phase, which is often set to zero at

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