käämitransformaattori

Käämitransformaattori, often referred to simply as a transformer, is a passive electrical device that transfers electrical energy from one circuit to another through electromagnetic induction. It typically consists of two or more coils of wire, known as windings, which are wound around a common ferromagnetic core. The primary winding is connected to an alternating current (AC) source, and the secondary winding is connected to a load.

The fundamental principle behind a transformer's operation is Faraday's law of induction. When an alternating current flows through the primary winding, it creates a changing magnetic flux in the core. This changing magnetic flux then induces an alternating electromotive force (EMF), or voltage, in the secondary winding. The ratio of the voltages in the primary and secondary windings is directly proportional to the ratio of the number of turns in each winding.

Transformers are crucial components in AC power systems. They are used to step up voltage for efficient long-distance power transmission and to step down voltage for safe distribution to homes and businesses. They are also used in a wide variety of electronic devices, such as power supplies, audio equipment, and switching circuits, to adjust voltage levels and provide electrical isolation between circuits. The core material, typically iron or ferrite, is designed to efficiently channel the magnetic flux, minimizing energy losses. Common types of transformers include step-up, step-down, isolation, and autotransformers, each serving specific applications based on their winding configurations and voltage transformation capabilities.