Växelströmstransformatorer

Växelströmstransformatorer, often simply called transformatorer, are electrical devices that transfer electrical energy between circuits through electromagnetic induction. They operate on the principle of mutual inductance, which is based on Faraday's law of induction. A transformer typically consists of two or more coils of wire wound around a common ferromagnetic core, or sometimes an air core. The coil connected to the AC power source is called the primary winding, and the coil connected to the load is called the secondary winding.

When an alternating voltage is applied to the primary winding, it creates a changing magnetic flux in the core. This changing magnetic flux then passes through the secondary winding, inducing an alternating voltage in it. The ratio of the voltages in the primary and secondary windings is approximately equal to the ratio of the number of turns in those windings. If the secondary winding has more turns than the primary, it is a step-up transformer, increasing the voltage. Conversely, if the secondary winding has fewer turns, it is a step-down transformer, decreasing the voltage.

Transformers are essential components in electrical power systems, used for stepping up voltages for efficient long-distance transmission and stepping them down for safe use in homes and industries. They are also found in numerous electronic devices, such as power adapters, chargers, and audio equipment, to adjust voltage levels as needed. The efficiency of a transformer is generally very high, often exceeding 95%, due to minimal energy losses during the energy transfer process. Their ability to change voltage levels without significantly altering the frequency of the AC power makes them indispensable in modern electrical engineering.