Can a substation transform voltage from a higher voltage to a lower voltage, or the reverse using transformers?

• A. Yes
• B. Only up
• C. No
• D. Only down

Answer: (A)

A transformer can change voltage levels in either direction. In a substation, that’s exactly how it’s used: to push voltage up for long-distance transmission or to pull it down for distribution to customers. The direction of the change depends on the turns ratio of the windings and how the connections are made. If the secondary winding has more turns than the primary, the voltage on the secondary will be higher than the input (step-up). If the secondary has fewer turns, the voltage on the secondary will be lower (step-down). The device itself simply transfers energy from one winding to the other, so it can be used to transform voltage up or down as needed, with losses accounting for the small reduction in efficiency.