Three-Phase Current - Definition and Generation
Three-phase current or 3-phase AC voltage plays a fundamental role in the transmission and distribution of electrical energy, as the energy can be transmitted with less material and power losses than, for example, with single-phase AC voltage. Three-phase AC is mainly used in industrial medium- and low-voltage networks, especially for supplying electric motors and other loads with higher power. But three-phase current can also be used in households, e.g. for an electric stove.
Definition: Three-phase alternating current is understood to be three alternating currents (or alternating voltages) of the same frequency, which are which are phase shifted to each other by 120°.
Three-phase current can be represented both in a line chart and as a pointer diagram. In the pointer diagram, the 3 pointers rotate counterclockwise. The pointer length corresponds to the peak value of one phase.
As you can see from the line chart, the sum of the three voltages is zero at any time. However, this means that if a load with 3 string resistors of the same size is connected to, the N-conductor (neutral conductor) can be omitted. More about this later.
Another advantage of a Three-Phase system is that it can supply both single-phase and three-phase loads.