Question

What is the formula for apparent power in a three-phase AC circuit?

Answer 1

The formula for apparent power in a three-phase AC circuit is given by:

Apparent Power (S) = √(3) × Voltage (V) × Current (I)

Where:

S is the apparent power in volt-amperes (VA).
√(3) is the square root of 3, which is approximately 1.732.
V is the line-to-line voltage in volts (V).
I is the current in amperes (A).

In a balanced three-phase AC circuit, the line-to-line voltage (V) refers to the voltage between any two phases, and the current (I) is the current in any one of the phases. The multiplication by √(3) accounts for the three phases in the circuit.

It's important to note that apparent power (S) represents the total power in the circuit, including both real power (measured in watts) and reactive power (measured in volt-amperes reactive or VARs). Real power is the actual power used to perform work, while reactive power is the power used to establish and maintain the electromagnetic fields in inductive or capacitive elements of the circuit. The combination of real and reactive power gives the apparent power.