Jännitemuuntaja

Jännitemuuntaja, also known as a transformer, is a passive electrical device that transfers electrical energy from one circuit to another through electromagnetic induction. It is commonly used to increase or decrease voltage levels in alternating current (AC) systems. A basic transformer consists of two or more coils of wire, called windings, which are electrically insulated from each other but are wound around a common ferromagnetic core.

The principle of operation relies on Faraday's law of induction. When an alternating current flows through the primary winding, it creates a fluctuating magnetic field in the core. This changing magnetic field then induces an electromotive force (EMF), or voltage, in the secondary winding. The ratio of the voltage in the primary winding to the voltage in the secondary winding is proportional to the ratio of the number of turns in each winding. If the secondary winding has more turns than the primary, it is a step-up transformer, increasing the voltage. If it has fewer turns, it is a step-down transformer, decreasing the voltage.

Jännitemuuntaja are essential components in power distribution systems, enabling the efficient transmission of electricity over long distances at high voltages and then stepping down the voltage for safe use in homes and industries. They are also found in a wide variety of electronic devices, such as power supplies for computers and televisions, charging adapters, and audio equipment, where they are used to match voltage requirements or provide electrical isolation between circuits. The core material is typically laminated iron to minimize energy losses due to eddy currents and hysteresis.