Wind speed measurement is an important component in the field of fluid velocity measurement

it has a very important significance to guarantee product quality

increases productivity efficiency and saves energy. Indepth study on thermal diffusion principle is undertaken

determines relationship between wind speed and heat power under constant temperature difference

through constant temperature difference control circuit

changes the supply currents

which makes the heat taken away by air supplemented

the measurement method eliminates effect of ambient temperature variation. The test results show that the constant temperature difference wind speed measurement method effectively increases measuring range

improves measurement precision

and provides a new method for wind speed measurement.