Power Supply Circuit

Calculating power drawn by AC circuit from a supply where the phase angle between I and V is 20º?

An AC circuit draws RMS current and voltage of 2A and 230V respectively from the standard UK power supply (230V RMS, 50Hz) – the phase angle between the current and voltage is 20º.

Calculate the power drawn by the AC circuit from the supply

The cosine of a 20 degree angle is .94, this is also the power factor of the circuit. The KVA of the circuit is .460 KVA (current times the voltage). Therefore the KW drawn by the circuit is KVA times the power factor = .460 * .94 = .4324 KW.

Experiments 1.1: Introductory Power Supply Circuit