What is the primary function of a transformer in electrical systems?

The primary function of a transformer in electrical systems is to change the voltage level of alternating current. Transformers operate based on the principle of electromagnetic induction, where an alternating current in one coil (the primary winding) creates a magnetic field that induces a voltage in another coil (the secondary winding). This allows for either an increase (step-up transformer) or a decrease (step-down transformer) in the voltage level while maintaining the power (minus some losses due to efficiency).

Transformers play a crucial role in power distribution, allowing electricity generated at power plants to be transmitted over long distances at high voltages, which reduces energy losses, and then stepped down to safer, usable voltages for residential or commercial use. Understanding the operation of transformers is fundamental to electrical systems, as they help manage and optimize electrical energy for various applications.