"220V AC Cooling Fan" is an important component of the stator of the motor, the motor of the silicon steel coil, PCB boards, namely the motor housing and the rotor magnetic stripe, here are generally soft magnetic stripe, external electromagnetic field to magnetic and magnetic stripe rushed together their magnetic, poles and "220V AC Cooling Fan" of the speed of the motor what to do with it, the conventional fan is usually 4-pole motor, which means that there are four coils, use IC to switch 4 magnetic field coils and the motor work without brushes, poles and more, on behalf of the magnetic field changes speed, high frequency IC switching coils, high frequency will increase the energy conversion efficiency of silicon steel, so the same current value can be obtained more high dynamic power, and thus "220V AC Cooling Fan" speed will increase, so the speed is proportional to the number of poles lean relationship