What is the purpose of a transformer in an aircraft electrical system?

The primary function of a transformer within an aircraft's electrical system is to increase or decrease voltage levels as needed. Transformers are essential components in managing electrical power distribution, allowing the system to step up voltage for transmission over longer distances or step down voltage for use by various aircraft systems.

In the context of an aircraft, different systems may require different voltage levels for optimal operation. For example, avionics, lighting, and other electronic components often have specific voltage requirements, and the transformer facilitates this adjustment. By effectively modifying voltage levels, transformers help ensure that all electrical systems receive the appropriate power without compromising performance or safety.

While the other options represent functions related to an aircraft's electrical system, they do not describe the role of a transformer specifically. Converting AC power to DC power pertains to rectifiers, storing electrical energy relates to batteries or capacitors, and switching circuits on and off involves circuit breakers or relays. Each of these components plays a critical role in the broader electrical network but does not serve the specific function of voltage modulation attributed to transformers.