How can single phase power be converted into three phase power and vice versa?

How to convert single-phase electricity to three-phase electricity

To convert single-phase electricity to three-phase electricity, a frequency converter is usually used to achieve this. The inverter uses electronic devices (such as MOSFET tubes, IGBT, etc.) to achieve the conversion between DC and AC, and outputs different phases or frequencies according to needs to achieve single-phase and three-phase conversion, the process is as follows:

• Rectifier: The single-phase power supply is first rectified through an electronic device to convert it into a DC voltage.

• Soft start: The soft start function enables on-demand frequency conversion and gradual voltage increase to ensure smooth current start and improve energy utilization efficiency.

• PWM control: Use PWM (Pulse Width Modulation) technology to control the switching frequency of electronic devices, so as to continuously change the level in a short time, control the size and phase of the output voltage, and achieve accurate control of the motor speed.

• Circuit adjustment: In order to make the output three-phase power supply have stability and meet the requirements of voltage, current, frequency and other characteristics, it is also necessary to do some special treatment of the original single-phase cable, such as the use of capacitors, coils and other circuits.

How to convert three-phase electricity to single-phase electricity

The process of converting three-phase electricity to single-phase electricity is relatively simple, and you only need to extract one phase and neutral line (zero line) from three-phase electricity to get single-phase electricity.

The specific steps are as follows:

• Select the phase line: Choose any one of the three phase lines of the three-phase electricity as the fire line of the single-phase electricity.

• Connect the neutral line: Connect the selected live line to the neutral line (neutral line) of the three-phase electricity.

Sum up

• Single-phase to three-phase: mainly rely on the technology of frequency converter, through the rectification, soft start, PWM control and other steps to complete the conversion.

• Three-phase to single-phase: simply extract the phase and neutral line from the three-phase electricity.

These two conversion modes have their own applicable scenarios and technical requirements in practical applications. The suitable conversion mode can meet the needs of different environments.