Single phase electricity consists of a live wire and a neutral wire, with a voltage of 220 volts between the live and neutral wires. This is the most basic form of electrical energy and is widely used in households and small appliances such as electric lights and rice cookers.

Two phase electricity, developed on the basis of single-phase electricity, is composed of alternating current from two phases. The voltage between any two live wires is usually 380 volts, commonly used in equipment such as welding machines. Two phase electricity has high power and stability, and is suitable for some small and medium-sized electrical appliances.

Three phase electricity consists of three sets of power sources and circuits, including three live wires and one neutral wire. The voltage between each set of live wires and neutral wire is 220 volts. Three phase electricity has high power and strong stability, and is suitable for various sizes of appliances such as electric motors, air conditioners, etc. It is widely used in industrial, commercial, and residential buildings.