conductor. Early systems used 4 wire two-phase with a 90° phase angle, but modern systems almost universally use three-phase voltage, with a phase angle of 120°
In electrical engineering, three-phase electric power systems have at least three conductors carrying alternating voltages that are offset in time by one-third
two-phase machines. Three-phasesystems eventually replaced the original two-phase power systems for power transmission and utilization. Active two-phase