Variable-frequency drive (VFD) is a power control device that controls the AC motor by changing the working frequency of the motor by applying variable frequency technology and microelectronic technology. The frequency converter provides the required power supply voltage according to the actual needs of the motor, thereby achieving the purpose of energy saving and speed regulation. In addition, the frequency converter has many protection functions, such as overcurrent, overvoltage, overload protection and the like. With the continuous improvement of industrial automation, inverters have also been widely used.

At present, the frequency converters used in centrifugal fans on the market are standard industrial frequency converters, and the inverters used by Hangzhou Aerzen Turbo, which is represented by Hangzhou Benmingwo Machinery Equipment Co., Ltd., are specially designed for Aerzen Turbo. Based on the real-time changes in oxygen demand, he can control between 40% and 100% through this dedicated frequency converter without mechanical control. In addition, this built-in dedicated inverter can continuously control the volume flow to prevent the fan from surge due to unexpected pressure fluctuations ( surge is a turbo compressor ( also called vane compressor ) when the flow rate is reduced to a certain level. A vibration that occurs under abnormal conditions. Surge has a serious hazard to centrifugal compressors .