Single-phase electricity is used in most homes and small businesses because it is relatively simple and inexpensive to install. Commercial and industrial businesses with larger electricity needs often prefer three-phase power because it is more efficient and less expensive. But what exactly is the difference between 1-phase and 3-phase electricity?
What is 3 phase electricity?
To illustrate the difference between single-phase and 3-phase power, imagine a person rowing a boat in a boat. When his paddle is on the water the raft will move but as soon as he lifts the paddle the thrust for the raft to move is zero.
Now imagine the same raft with 2 or more rowers. When one person lifts the paddle and the other immediately puts it down, the raft receives a steady and constant push to move it forward. The rowers act as conductors inside the power cable, electricity will be transmitted continuously with more clock stability, thus ensuring stability for the power source to use the devices. electricity.
In fact
Distinguishing 1 phase power from 3 phase
To understand 1-phase and 3-phase current, it is necessary to first understand the nature of the neutral conductor.
Neutral conductive core, also known as cold conduction core, cool core, etc., is used for the purpose of keeping voltage stable when electricity is transmitted. The neutral core theoretically has a potential = 0V, does not cause electric shock, but in fact the wire still has a small potential > 0V and it is best to be careful.
So in theory, in order to transmit electricity, electric cables must have a hot conductor core (phase core) and may have a neutral conductor core (or not), such as high voltage cable / medium voltage cable / cable. low voltage type 1 core.
Power 1 phase
In practical application, single-phase electricity uses a conductor with 2 cores, including 1 hot core and 1 cold core. Single-phase electricity is used in most homes and small businesses, enough to run electrical appliances up to 5Hp~ 3.5kW.
However, in fact, there are many electrical equipment and machinery that need to use a larger and more stable power source, so 3-phase electricity has been researched, built and developed from the early 1880s, to 1888 generators. 3-phase and 3-phase electric motors were first announced by founder Mikhail Dolivo-Dobrovolsky, marking the basis of 3-phase voltage today.
3 phase electricity
3-phase electricity uses power cables with 3 phase cores (3 hot cores) and 1 neutral core instead of 2-core wires like 1-phase electricity, so a 3-phase power cable has a total of 4 conductive cores. In fact, 3-phase electricity also has 3 hot- core cables and no neutral core, the purpose of this line of power cables is to transmit voltage between stations, not to transmit electrical equipment (because There is no neutral core, so voltage stability is not good, use can be dangerous).
In some cases, with machines with advanced technology, they also use 3-phase power cables of 5 cores, 6 cores… in which 1 neutral core is used and the other is phase core (hot core). 4-core 3-phase power cables are the most common .
Note: Wires using 2 phase cores (which may or may not have an additional neutral core) are called 2-phase electricity. This is a rather special and interesting power source, we will learn later.
Electric difference 1 phase with 3 phase
Based on the data provided by SUNWON above, you can see that the biggest difference between 1-phase and 3-phase power is consistency. 3-phase power supply offers more stability and uniformity than single-phase power because there is no pulsation of the transmitted voltage (example at the beginning of the article).
In addition, 1 phase and 3 phase electricity have some other differences as follows:
- Single phase power supply can carry voltage up to 230V, three phase power supply can carry voltage up to 415V.
