Transformers (electrical) - Basic Principles

Basic Principles

The transformer is based on two principles: first, that an electric current can produce a magnetic field (electromagnetism) and second that a changing magnetic field within a coil of wire induces a voltage across the ends of the coil (electromagnetic induction). Changing the current in the primary coil changes the magnetic flux that is developed. The changing magnetic flux induces a voltage in the secondary coil.

An ideal transformer is shown in the adjacent figure. Current passing through the primary coil creates a magnetic field. The primary and secondary coils are wrapped around a core of very high magnetic permeability, such as iron, so that most of the magnetic flux passes through both the primary and secondary coils. If a load is connected to the secondary winding, the load current and voltage will be in the directions indicated, given the primary current and voltage in the directions indicated (each will be alternating current in practice).

Read more about this topic:  Transformers (electrical)

Famous quotes containing the words basic and/or principles:

    When you realize how hard it is to know the truth about yourself, you understand that even the most exhaustive and well-meaning autobiography, determined to tell the truth, represents, at best, a guess. There have been times in my life when I felt incredibly happy. Life was full. I seemed productive. Then I thought,”Am I really happy or am I merely masking a deep depression with frantic activity?” If I don’t know such basic things about myself, who does?
    Phyllis Rose (b. 1942)

    It must appear impossible, that theism could, from reasoning, have been the primary religion of human race, and have afterwards, by its corruption, given birth to polytheism and to all the various superstitions of the heathen world. Reason, when obvious, prevents these corruptions: When abstruse, it keeps the principles entirely from the knowledge of the vulgar, who are alone liable to corrupt any principle or opinion.

    David Hume (1711–1776)