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

The primary function of a transformer in electrical systems is to alter the voltage of electrical power. Transformers are electrical devices that utilize electromagnetic induction to change the voltage level of alternating current (AC) while maintaining the same power level, minus minor losses due to heat. This capability is essential for both increasing voltage for efficient transmission over long distances (step-up transformers) and decreasing voltage for safe distribution and use in residential or commercial settings (step-down transformers).

Transformers are crucial in the power distribution network because higher voltage levels reduce current for a given power level, which diminishes energy loss due to resistance in the wires over long distances. When the voltage is adjusted appropriately using transformers, it allows for safe and efficient delivery of electrical power to end-users.

Other functions listed, such as converting energy into electrical power, storing electrical energy temporarily, or disconnecting power during maintenance, do not align with the fundamental operation of a transformer. These are handled by different types of devices within electrical systems, such as generators, capacitors, and circuit breakers, respectively. Thus, the role of a transformer is specifically focused on voltage alteration, making that the correct answer.