Explain how a star connection is different from a delta connection
Delta is a parallel circuit where line voltage and phase voltage are equal. Star is a series circuit where line current and phase current are equal. Delta connections are used in parallel…33kv lines…ie high tension… while star connections are step down…230v…ie…low tension. Star provided low torque while Delta provides high torque.
Star winding is required to detect ground fault currents in the power system.To balance mechanical forces in generator stator, otherwise, it may fly away on faults.Delta stabilized voltages on system faults, trap third harmonics and close zero sequence currents during earth faults
Delta for transmission
Star for distribution (balancing load)
Delta has, line voltage= phase voltage
Line current= √3× phase current
Star has, line voltage =√3 × phase voltage
Line current= phase current