Vekselsstrømsspenninger

Vekselsstrømsspenninger, often abbreviated as AC voltage, refers to the electrical potential difference that periodically reverses direction. This is in contrast to likestrømsspenninger (DC voltage), which maintains a constant polarity. AC voltage is the standard form of electricity delivered to homes and businesses worldwide.

The characteristic of AC voltage is its sinusoidal waveform, meaning it fluctuates smoothly between a positive and negative peak value over time. The frequency of this fluctuation is measured in Hertz (Hz), indicating the number of cycles per second. In most countries, the standard frequency is 50 Hz or 60 Hz. The magnitude of the AC voltage is typically described by its RMS (Root Mean Square) value, which represents the equivalent DC voltage that would produce the same amount of heat in a resistor.

AC voltage is generated by alternators, which use rotating magnetic fields to induce a changing voltage. The advantage of AC voltage lies in its ability to be easily transformed to higher or lower levels using transformers. This makes it efficient to transmit electricity over long distances at high voltages, reducing power loss, and then step it down to safer, usable levels for consumers. Common examples of AC voltages include household outlets (e.g., 230V in Europe, 120V in North America) and high-voltage transmission lines.