Three phase transformer winding

In the market now,commonly it have three methods of three phase transformer winding such as a star, delta and zig-zag. Each method can be applied to either or both of the primary and secondary winding of transformer.

This connection must suitable with our output voltage for application and equipment.We should decide which connection is suitable and not effected when power supply energizes.

This 3 types of winding is used for different application and we need to identify a suitable condition to apply this types of transformer winding.This time i want shared some information about transformer winding.

Types of Transformer Winding

1) Star winding

Its are used when a neutral connection is required for earthing or for unbalanced loads (these are usually groups of single-phase loads placed between separate phases of the supply and its neutral. Each group may not be identical and hence the system will be unbalanced).

2) Delta winding

Its are most frequently used on the high voltage winding, which is usually the winding connected to the supply.The delta connection also allows third harmonic currents to circulate which improves the waveforms of the line currents and voltages on both side of the transformer.Delta windings may be slightly more expensive because the insulation has to withstand the full line-to-line voltage.

3) Zig-zag winding

Its requires each three-phase winding to be split in half. Each half is interconnected with a half-winding on another core limb. Zig-zag windings are used to suppress third harmonics or to provide a neutral connection as an earthing transformer, and to obtain a phase angle shift. Zig-zag windings are sometimes used for power rectifier circuits when high order harmonic can be nuisance and have to be minimized.