Power Triangle Diagram

1. Apparent Power (S)

Apparent power represents the total power delivered to a circuit. In three-phase systems, it's calculated using:

Where:

• \(V_{L-L}\): Line-to-line voltage (V)
• \(I\): Line current (A)
• \(\sqrt{3}\): Three-phase constant (≈ 1.732)

Unit: Volt-Ampere (VA)

2. Active Power (P)

Active power, also known as real power, represents the actual power consumed by the load to perform useful work:

Where:

• \(S\): Apparent power (VA)
• \(pf\): Power factor (0 to 1)

Unit: Watt (W)

3. Reactive Power (Q)

Reactive power is the power used to maintain electromagnetic fields in inductive or capacitive loads:

Where:

• \(S\): Apparent power (VA)
• \(P\): Active power (W)

Unit: Volt-Ampere Reactive (VAR)

Key Points

• Power factor (pf) indicates how efficiently electrical power is being used
• Higher power factor (closer to 1) means more efficient power usage
• Lower reactive power generally indicates better system efficiency