380V refers to the line voltage of general civil three-phase alternating current, and 220V refers to the phase voltage.

Line voltage refers to the voltage between three-phase lines, and phase voltage refers to the voltage between each phase and neutral line or neutral line.

Because the phase angle difference between each phase of three-phase electricity is 120 degrees, the line voltage = phase voltage ×√3.

That is, 220V×√3=38 1V≈380V.