List of top Electrical Engineering Questions on Transformers

An auto-transformer is most efficient when the transformation ratio ($K = V_2/V_1$) is:

For two three-phase transformers to operate in parallel, which of these is an absolute requirement?

A 200/100 V transformer has a primary resistance of 0.1 $\Omega$. What is this resistance when referred to the secondary side?

In a single-phase transformer, the core is laminated primarily to reduce:

An autotransformer converts 200V to 100V supplying same load. Copper saving is

What is the major disadvantage of an auto transformer?

A three-phase transformer has 600 primary turns and 150 secondary turns. If the supply voltage is 1.5 kV determine the secondary line voltage on no-load when windings are connected in delta-star.

A single phase transformer is rated at 40 kVA. The transformer has full-load copper losses of 800 W and iron losses of 500 W. Determine the transformer efficiency at half full-load and 0.8 power factor.

A 6 kVA, 100 V/500 V, single phase transformer has a secondary terminal voltage of 485.50 Volts when loaded. Determine the regulation of the transformer.