sähkömuuntajan

A sähkömuuntaja, or electrical transformer in English, is a passive electrical device that transfers electrical energy from one electrical circuit to another through electromagnetic induction. It is most commonly used to increase (step-up) or decrease (step-down) voltage levels between circuits, while altering the currents accordingly. This voltage transformation is crucial for efficient power transmission over long distances, as higher voltages reduce current, thereby minimizing resistive losses in the transmission lines. Transformers are fundamental components in electrical power systems, found in everything from power generation plants to substations and consumer electronics.

The operation of a sähkömuuntaja relies on Faraday's law of induction. It typically consists of two or more windings, known as coils, which are electrically isolated but magnetically linked by a common iron core. When an alternating current (AC) flows through the primary winding, it creates a changing magnetic flux in the core. This changing magnetic flux then induces an alternating electromotive force (voltage) in the secondary winding. The ratio of the number of turns in the primary and secondary coils determines the voltage transformation ratio. If the secondary coil has more turns than the primary, the voltage is stepped up; if it has fewer turns, the voltage is stepped down. Transformers are designed to operate only with alternating current, as a constant direct current would not produce a changing magnetic flux.