Why Three-Phase Power?
Nearly all commercial and industrial electrical power is delivered as three-phase AC power. Three-phase systems have three advantages over single-phase: they deliver more power with less conductor material, they produce smoother power delivery (useful for motors), and the instantaneous power remains nearly constant rather than pulsing at twice the line frequency. Most large motors, HVAC compressors, elevators, and industrial equipment require three-phase power to operate efficiently.