Transformer

The utility model discloses a transformer. The transformer comprises at least two cores, I-shaped bars for dissipating heat are arranged between the cores, inner coils are arranged on the outsides of the cores, outer coils are arranged on the outsides of the inner coils, and I-shaped bars for dissipating heat are arranged between inner coils and the outer coils. Because the heat dispersion of the transformer provided by the utility model is good, the temperature of the transformer is low after the transformer is used in a high-temperature environment for a long time, consequently, the service lives of the coils can be prolonged, and fire hazards can be reduced.