What is 'three-phase power'?

Three-phase power refers to a method of electrical power generation and delivery that utilizes three alternating currents, which are delivered on three separate conductors. This system is particularly efficient for transmitting electrical energy over long distances and is widely used in industrial and large commercial applications.

The key advantage of three-phase power is its ability to provide a constant energy transfer, creating a more stable and efficient power supply compared to single-phase systems. In a three-phase setup, the currents reach their peak values at different times, which helps to maintain continuous power delivery. This results in smoother operation of motors and reduced vibrations and stress on electrical equipment.

In contrast, other choices do not correctly define three-phase power. For example, a single-phase power supply only uses one alternating current, and a direct current electrical system does not involve alternating currents at all. Additionally, using two currents is not a characteristic of three-phase power, making that option incorrect as well. Therefore, the choice that accurately describes three-phase power as a method of providing continuous energy transfer through three alternating currents is correct.