Working principle of VFD
The working principle of frequency converters is to apply the principles of frequency conversion technology and microelectronics technology to control the power control equipment of AC motors by changing the frequency of the motor's working power supply.
The power supply used is divided into AC power supply and DC power supply. Generally, DC power supply is mostly obtained by AC power supply through transformer transformation, rectification and filtering. AC power accounts for about 95% of the total power used by people.
A frequency converter is a device that converts industrial frequency power sources (50Hz or 60Hz) into AC power sources of various frequencies to achieve variable speed operation of the motor. The control circuit controls the main circuit, the rectifier circuit converts AC power into DC power, the DC intermediate circuit smooths and filters the output of the rectifier circuit, and the inverter circuit converts DC power back into AC power.
