Power in Balanced system

SUMMARY of WYE and Delta connections formula

DELTA-WYE Connection

example,


A balanced Y-connected load with a phase impedance of is 40 + j 25 ohmssupplied by a balanced, positive sequence -connected source with a linevoltage of 210 V. Calculate the phase currents. Use 
Vab as reference.

Balanced DELTA-DELTA connection

WYE - DELTA connection

WYE-WYE connection

    EXAMPLE:

A Y-connected balanced three-phase generator with an impedance of 0.4+j 0.3 ohms per phase is connected to a Y-connected balanced load with an impedance of 24- + j19 ohms per phase. The line joining the generator and the load has an impedance of 0.6 + j0.7 ohms per phase. Assuming a positive sequence for the source voltages and that Van = 120 ∠ 30 °  V, find : (a) the line voltages, (b) the line currents.

Balanced Three-Phase Voltages