Three phase current is better than single phase

Designed to drive multiphase electric motors using a rotating magnetic field, the three -phase current system is still used to transmit electricity at a distance. The thing is, the three -phase alternating current, unlike single -phase, has a number of important advantages:

1. The consumption of materials for power cables is significantly reduced when using three phases, because for the same power consumption, the currents in the phases decrease, and if we imagine the transmission of the same power through three single-phase lines and then compare with the transmission of the same power through a three-phase line, yes Even taking into account the difference in voltages, the benefit of the volumes used to transfer materials becomes apparent.

2. Three-phase current can be converted using several single-phase transformers for separate circuits, or one three-phase transformer can be used. Using a three-phase transformer is more economical, again due to lower material consumption.

3.Possibility of obtaining two working voltages in one installation: phase (between phase and zero) and linear (between two phases of the line), respectively, two power levels are available when the load is connected to «star» or «delta».

4. The unconditional possibility of obtaining a rotating magnetic field of the stator — the main condition for the operation of an electric motor and many other electrical devices. Both synchronous and asynchronous three-phase motors are simpler than other types of common motors (single-phase, two-phase, direct current) and have fairly high coefficients of efficiency compared to them.

5. With the use of a three-phase power supply circuit for fluorescent lamps, flicker and stroboscopic effect are sharply reduced. A light fixture contains three groups of lamps, each powered by a separate phase (or just three lamps, one for each phase).

6. One of the most important advantages of three-phase current is the balance of the system as a whole. The load on the power generation unit can be distributed as evenly as possible, and this significantly extends the service life of the power generation equipment, since uneven loading here is destructive.

These advantages of three-phase systems make them the most common in modern power generation.