The fan speed regulation function is achieved by changing the motor speed, and its core principle is closely related to the motor's power supply method. Currently, there are two common speed regulation methods: inductive speed regulation and electronic speed regulation. Inductive speed regulation changes the input voltage of the motor by connecting inductance coils of different specifications in series. Inductance coils have the characteristic of hindering current changes. The more turns of the series coil, the greater the voltage attenuation, the lower the voltage obtained by the motor, and the slower the speed, thereby realizing the switching of low, medium, and high wind speeds. This speed regulation method has a simple structure and low cost, and is widely used in traditional floor fans and table fans. However, the voltage change during speed regulation will cause a slight decrease in motor efficiency, and the wind speed gears are relatively fixed.​

Electronic speed regulation achieves stepless speed regulation or multi-gear precise speed regulation by changing the power supply frequency or duty cycle of the motor through electronic components (such as thyristors). Thyristors can accurately control the conduction time of current, thereby changing the input power of the motor and then adjusting the speed. The advantages of electronic speed regulation are smoother wind speed adjustment, the ability to select any speed according to needs, higher motor efficiency, and relatively lower energy consumption. It is currently mostly used in new types of fans such as tower fans and bladeless fans. Some high-end fans are also equipped with intelligent speed regulation functions, which automatically adjust the wind speed through built-in sensors to detect ambient temperature or human distance, improving user comfort.​

Reasonable use of the speed regulation function can enhance the experience and save energy consumption. First, select the gear according to the ambient temperature and human state: when the ambient temperature is high (above 30℃) or there are many people, you can choose medium and high wind speeds to quickly promote air circulation and reduce the ambient temperature; when the ambient temperature is moderate (25-30℃) or used by a single person, medium and low wind speeds can meet the needs, avoiding discomfort such as dry skin and headaches caused by excessive wind speed. Secondly, adjust according to the use scenario: when working or studying, choose a gentle medium and low wind speed to avoid strong wind affecting concentration; when sweating a lot after exercise, you can first use high wind speed to cool down quickly, and switch to low wind speed after sweating decreases to prevent catching cold.​

When using at night, it is recommended to turn on the timing function with low wind speed. Because the human body's metabolism slows down during sleep, and the perception of temperature is more sensitive. Blowing with high wind speed for a long time is likely to cause colds, joint pain and other problems. Timed shutdown can avoid such situations. In addition, avoid frequent switching of wind speed gears. Frequent changes in motor speed will increase motor load, accelerate part wear, and consume more electrical energy. If the fan supports stepless speed regulation, you can slowly adjust to the appropriate wind speed to reduce the impact on the motor. It should be noted that when starting the fan, you can briefly use high wind speed to make the blades quickly reach a stable speed, and then switch to the required gear. This can reduce the load when the motor starts and extend the service life.