Phasor Real Part (Polar → Rect)

Formula

Description

Converting a phasor from polar to rectangular form, the real (in-phase) component is the magnitude times the cosine of the phase angle. This is the resistive part of an impedance or the in-phase part of a voltage or current, and it is what determines real power dissipation. It is the projection of the phasor onto the real axis.

Variables

• R — Real / in-phase component (Ω)
• |Z| — Phasor magnitude (Ω)
• θ — Phase angle (degrees)

Practical Notes

The imaginary part is X = |Z|·sin(θ). For power, the real component of current times voltage gives true (watt) power; the imaginary gives reactive (VAR) power.