Spectacular Diagram Of 3 Phase Transformer

A three phase transformer is built for a specific connection and voltage transformation and the unit will have a nameplate with the internal connections shown.

Diagram of 3 phase transformer. 1 transformer when excited at no load only takes excitation current which leads the working flux by hysteretic angle α. Core type and shell type. Practically almost every electrical power system deals with three phase power.

In order to reduce the power loss to the distribution end the power is transmitted at somewhat higher voltages like 132 or 400kv. Similarly v bn leads v bn by 30º and v cn leads v cn by 30º this connection is also called 30º connection. The phasor diagram of the y connection of the three phase transformer is shown in the figure below.

Core type construction. Flux of each limb uses the other two limbs for its return path with the three magnetic flux s in the core generated by the line voltages differing in time phase by 120 degrees. Important points for phasor diagram of transformer.

The connection diagram on the left shows how a delta delta connection can be made either with three single phase transformers or with one three phase transformer. The power generated at various generating stations is in three phase nature and the voltages are in the range of 13 2kv or 22kv. Three phase transformers are used to step up or step down the high voltages in various stages of power transmission system.

When a single unit or bank of three is used there are four types of connections. The dashed lines indicate the transformer outlines. A transformer three phase vector diagram is required for determining the fault calculation of an electrical power system.

2 excitation current is made up of two components one in phase with the applied voltage v is called core loss component i c and another in phase with the working flux ø called magnetizing current i m. Three phase transformer core has three sets of windings. But if three identical coils each with the same number of coil turns are placed at an electrical angle of 120 o to each other on the same rotor shaft a three phase voltage supply would be generated.