Transformer vs. Coupled Inductor

Definition

 A transformer utilizes a non-gap magnetic core to convert voltage between primary and secondary coils and delivers power in real-time. On the other hand, a coupled inductor employs a gapped magnetic core to convert voltage between primary and secondary coils and delivers power at controlled time intervals.

Key Difference

The transformer does not store energy in its core, whereas the coupled inductor stores energy in its core. It's important to note that energy is stored as magnetic flux within the magnetic core gap.

Application

Transformers are commonly used in AC to AC conversion applications, such as stepping down the voltage from a standard AC wall outlet (e.g., 120Vac) to a lower voltage (e.g., 24Vac). Coupled inductors find their application in DC to DC converters, such as flyback converters, where they step down a higher DC voltage (e.g., 24V DC) to a lower DC voltage (e.g., 5V DC).

Summary

• Transformers use a non-gap magnetic core and deliver power in real-time, while coupled inductors utilize a gapped magnetic core and deliver power at controlled time intervals.

• Transformers do not store energy in their core, whereas coupled inductors store energy as magnetic flux within the core gap.

• Transformers are commonly used for AC to AC conversion, stepping down voltages from sources like AC wall outlets.

• Coupled inductors find application in DC to DC converters, stepping down higher DC voltages to lower DC voltages, such as in flyback converters.