likestrømmen

Likestrømmen, often abbreviated as DC, refers to the unidirectional flow of electric charge. Unlike alternating current (AC), where the direction of current flow reverses periodically, in direct current, the electrons move consistently from the negative terminal to the positive terminal. This constant flow makes direct current a fundamental concept in electricity and electronics.

The primary source of direct current is often batteries, which convert chemical energy into electrical energy. Other sources include solar cells, fuel cells, and DC generators. The voltage in a DC circuit is typically constant over time, though some applications may involve varying DC voltages that do not reverse polarity.

Direct current is crucial for the operation of many electronic devices. Semiconductors, microchips, and most portable electronic gadgets rely on DC power. The power supply units in computers and other electronics convert AC from the mains to DC before it can be used by internal components. Transmission of electricity over long distances is more efficiently done using AC due to easier voltage transformation. However, for specific applications like high-voltage direct current (HVDC) transmission, DC is used, particularly for interconnecting asynchronous grids or minimizing transmission losses over very long distances. Understanding the principles of direct current is essential for anyone working with electrical circuits and systems.