Electronic commutation fan system

The invention provides an electronic commutation fan system. The electronic commutation fan system comprises an AC/DC conversion unit, an inverter unit and a control unit, wherein the AC/DC conversionunit is used for converting an AC input power supply into a first DC power supply; the inverter unit is electrically connected between the AC/DC conversion unit and a fan, converts the first DC powersupply into an AC output power supply and supplies the AC output power supply to the fan to rotate; the control unit is electrically connected with the AC/DC conversion unit and the inverter unit andadjusts the rotating speed of the fan by controlling the AC/DC conversion unit and the inverter unit; when detecting that the magnitude of the AC input power supply changes, the control unit controlsthe rotating speed of the fan to be kept within a first error range. The electronic commutation fan system provided by the invention can be compatible with most of input voltages so as to achieve thetechnical effect of providin