What is the function of a transformer in a power system?

The primary function of a transformer in a power system is to change the voltage level of alternating current (AC). Transformers operate on the principle of electromagnetic induction, allowing them to either step up (increase) or step down (decrease) voltage levels between circuits while maintaining the same frequency. This capability is essential for the efficient transmission and distribution of electrical energy over long distances, as it helps reduce energy loss that occurs due to resistance in wires.

In electrical power systems, higher voltages are used for transmission to minimize current and thus reduce losses, while lower voltages are used for distribution to end users. This ability to manage voltage levels is crucial in ensuring that the power delivered is at the appropriate voltage for safe and effective use by consumers and industries.

The other choices describe functions that are not the role of a transformer within a power system. For example, transformers do not store electrical energy, convert AC to DC, or regulate temperature within electrical systems. Each of these functions is associated with different devices or systems within the electrical grid.