What does the apparent power (Pkva) equation for a 3P WYE Transformer involve?

The apparent power (Pkva) equation for a 3-phase WYE (or star) transformer is derived from the fundamental principles of power in three-phase systems. In this context, the correct calculation involves using the line current (IL) and the phase voltage (EL).

Apparent power is calculated using the formula Pkva = √3 × VL × IL, where VL represents the line voltage. Since in a WYE configuration, the line voltage (VL) is related to the phase voltage (EL) by the equation VL = √3 × EL, substituting into the formula gives:

Pkva = √3 × (√3 × EL) × IL = 3 × EL × IL

However, due to the structure of the choices given, the choice that accurately expresses the computation of apparent power in terms of the line current and the phase voltage is IL x EL x 1.732.

Here, 1.732 approximates the square root of 3 (√3). The use of line current (IL) as part of the formula is crucial because it reflects the current entering the transformer and represents the operational aspect of the system. Using the line current along with the phase voltage allows for an accurate representation of