Which transformer increases voltage?

A step-up transformer is designed specifically to increase voltage from the primary side to the secondary side. This type of transformer operates on the principle of electromagnetic induction and is characterized by having more turns of wire in the secondary coil than in the primary coil. When an alternating current flows through the primary winding, it creates a magnetic field that induces a higher voltage in the secondary winding due to the increase in the number of turns. The increased voltage allows for efficient transmission of electrical power over long distances, making step-up transformers crucial in power distribution systems.

In contrast, the other types of transformers serve different purposes. A step-down transformer decreases voltage, while an impedance transformer matches impedance levels between circuits without notably altering voltage in a way that is specifically meant to transform it. An auto transformer can either step up or step down voltage depending on how it is connected but does not inherently increase voltage. Therefore, the step-up transformer is distinctly recognized for its role in boosting voltage levels.