Three Phase Transformers

Open delta transformers can be obtained from

When we magnetize the ferromagnetic core of the transformer, core length_______ and it ______ when demagnetized.

Below is the circuit diagram for delta-delta transformer have a transformation ratio ‘k’. The current flowing in the windings of phase r-y in the below diagrams is

While using three phase transformers, it is taken care about the third harmonics current in the system.
This is present when transformer set is delta on either side.

Shape of emf generated by delta connected transformer is not always sinusoidal.

A. Positive sequence components – 7th harmonic component
B. Negative sequence components – 5th harmonic component
C. Zero sequence components – 3rd harmonic component
Above are the matching made for the harmonics and the associated harmonic component, then the correct marking is

he voltage across the terminal ‘r’ and ‘y’ is

The delta-delta connections are used in applications of

For the given circuit below, the voltage across the terminal ‘a’ and ‘b’ is

If para magnetic core is used in the place of the ferromagnetic core of the transformer, then magnetostriction will

A V-V connected transformer can be connected in parallel to delta-delta connected transformer but not to

Three units of single phase transformers and one single three-phase transformer rating

A 400 V, 10 KVA transformer at 50 Hz, is operated at the frequency of 40 Hz, then the humming

If one of the transformers is removed from the bank of only delta-delta, then it behaves with 58% power delivery.

A recording of the output of the emf induced for star and delta are recorded.
Then shape of the emf induced in Y-connected 3-phase transformer is non sinusoidal in nature due to

The transformer which is more feasible to use in the distribution ends should be