What is the formula for the phase current of a delta winding?

The phase current in a delta winding is derived from the relationship between the line current and the phase current. In a delta-connected system, each phase is connected across two lines, resulting in a distinctive way to calculate phase currents.

The formula states that the phase current is equal to the line current divided by the square root of three. This is because in a balanced three-phase system, the line current is the vector sum of the phase currents. Each phase current is effectively smaller than the line current by a factor of √3 due to the geometry of the current flow in a three-phase system.

In terms of understanding the operation of a delta connection, when you look at a single phase of the delta winding, the phase current is distributed between the two line currents connected to that phase. The relationship arises from the angles in the phasor diagram representing the three phases, where the currents lag and lead each other by 120 degrees. Thus, the calculation yields that the phase current equals the line current divided by √3, validating the given formula.

This understanding is crucial in electrical engineering applications, particularly when designing and analyzing three-phase systems and ensuring proper load distribution.