Balanced 4-Wire Three-Phase Power System: Calculating Current Supplied by Each Phase

If the magnitude of the line current in a balanced 4-wire (wye) three-phase power system is 25 amps, what is the current supplied by each phase?

The current supplied by each phase in a balanced 4-wire (wye) three-phase power system with a line current of 25 amps is approximately 14.4 amps.

Understanding the Calculation

In a balanced 4-wire (wye) three-phase power system, the line current represents the total current flowing through all three phases. Each phase in a three-phase system carries one-third of the total power.

Calculation Formula

To determine the current supplied by each phase, we need to divide the line current by the square root of 3. This is because the line current is the vector sum of the three phase currents, and the square root of 3 is the ratio between the line current and the phase current in a balanced system.

Calculation Process

Current per phase = Line current / √3

Given line current = 25 amps

Current per phase ≈ 25 amps / √3 ≈ 14.4 amps

Conclusion

Therefore, in a balanced 4-wire (wye) three-phase power system with a line current of 25 amps, each phase supplies approximately 14.4 amps of current. Understanding this calculation is essential in electrical engineering and power distribution.