Star and Delta Connections

STAR AND DELTA CONNECTIONS

We seen the 3 phase concept and now we can discuss the star and delta connection for 3 phase supply. Actually where is these connections exist? The answer is at

·       Transformers(Both power and instrumentation).

·       At motor winding.

·       At generator winding.

Actually where we handle the 3 phase supply directly, we can prefer the star or delta connection. Previous post i mentioned that only 3 phase loads are motors,so you may confuse about the transformers, actually transformer is not a load. It just change the voltage level.

Delta connection is also used to connect the windings of most three-phase motors because the phase windings are perfectly balanced and, therefore, do not require a neutral connection.

           Making a star connection has the advantage that two voltages

become available – a line voltage between any two phases, and a

phase voltage between line and neutral which is connected to the star point.

          In any star-connected system currents fl   ow along the lines ( IL), through the load and return by the neutral conductor connected to the star point. In a balanced  three-phase system all currents have the same value and when they are added up by phasor addition, we find the resultant current is zero.