Question

In a three-phase balanced wye-wye system, the source is an abc-sequence set of voltages with V_an = 120/40 degree V rms. The per phase impedance of the load is 10 + j 8 Ohm. It the line impedance per phase is 0.6 + j 0.4 Ohm, find the line currents and load voltages.

Answer 1

In a three-phase balanced wye-wye system, the line currents can be found by dividing the line-to-neutral voltages by the line impedance per phase. The load voltages will be equal to the line-to-neutral voltages.

Step-by-step explanation:

In a three-phase balanced wye-wye system, the line currents can be found by dividing the line-to-neutral voltages by the line impedance per phase. In this case, the line-to-neutral voltage is given as Van = 120/40° V rms. So, to find the line currents, we divide the Van by the line impedance per phase, which is 0.6 + j 0.4 Ohm. Using Ohm's law for AC circuits, we have:

Ian = Van / Zline

In the same way, we can find the line currents for the other two phases. Now, to find the load voltages, we can use the relation between the line-to-neutral and line voltages. In a balanced wye-wye system, the line-to-neutral voltage is equal to the line voltage. So, the load voltages will also be equal to the line-to-neutral voltages Van.