enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Direct current - Wikipedia

    en.wikipedia.org/wiki/Direct_current

    Types of direct current. The term DC is used to refer to power systems that use only one electrical polarity of voltage or current, and to refer to the constant, zero-frequency, or slowly varying local mean value of a voltage or current. [9] For example, the voltage across a DC voltage source is constant as is the current through a direct ...

  3. Electric current - Wikipedia

    en.wikipedia.org/wiki/Electric_current

    In contrast, direct current (DC) refers to a system in which the movement of electric charge in only one direction (sometimes called unidirectional flow). Direct current is produced by sources such as batteries, thermocouples, solar cells, and commutator-type electric machines of the dynamo type.

  4. Current source - Wikipedia

    en.wikipedia.org/wiki/Current_source

    An ideal current source generates a current that is independent of the voltage changes across it. An ideal current source is a mathematical model, which real devices can approach very closely. If the current through an ideal current source can be specified independently of any other variable in a circuit, it is called an independent current source.

  5. Sources of electrical energy - Wikipedia

    en.wikipedia.org/wiki/Sources_of_electrical_energy

    The electric field sends the electron to the p-type material, and the hole to the n-type material. If an external current path is provided, electrical energy will be available to do work. The electron flow provides the current, and the cell's electric field creates the voltage. With both current and voltage the silicon cell has power.

  6. High-voltage direct current - Wikipedia

    en.wikipedia.org/wiki/High-voltage_direct_current

    Long distance HVDC lines carrying hydroelectricity from Canada's Nelson River to this converter station where it is converted to AC for use in southern Manitoba's grid. A high-voltage direct current (HVDC) electric power transmission system uses direct current (DC) for electric power transmission, in contrast with the more common alternating current (AC) transmission systems. [1]

  7. Alternating current - Wikipedia

    en.wikipedia.org/wiki/Alternating_current

    A direct current flows uniformly throughout the cross-section of a ... The other essential milestone was the introduction of 'voltage source, voltage ...

  8. Constant current - Wikipedia

    en.wikipedia.org/wiki/Constant_current

    In electronics, a constant current system is one that varies the voltage across a load to maintain a constant electric current.When a component is indicated to be driven by a constant current, the driver circuit is, in essence, a current regulator and must appear to the component as a current source of suitable reliability.

  9. Electric generator - Wikipedia

    en.wikipedia.org/wiki/Electric_generator

    A dynamo uses commutators to produce direct current. It is self-excited, i.e. its field electromagnets are powered by the machine's own output. Other types of DC generators use a separate source of direct current to energise their field magnets.