In a modern society that promotes environmental protection, people use natural energy, such as solar energy, wind energy, etc., but use wind energy also requires an instrument to control it, so wind speed sensors are created, and this is an instrument to measure wind speed. Such sensors may be alien to their operation and have no clue about their circuits. So we need to learn about wind speed sensors circuits, which are fully understood by them。
I: wind speed-frequency converter
Wind speed - frequency conversion is the core of the wind speed sensor, consisting mainly of slot-type pv switches and flat-open discs rotating with wind cups。
The center speed of the center of the wind cup is v ' , the center of the axis to the centre of the wind cup is r, the wind cup rotates n-second
Then v'=2πr*n
Wind speed, k=v/v ' , k is the wind speed conversion factor, which is available through wind tunnel experiments
:v=k *v'=k*2πr*n
When the pv switch is applied to the normal voltage after the pv switch is applied, each week from the middle of the pv switch, the ax pulse wind velocity - frequency change circuit output pulse frequency: f=a*n=a/(2πk*r)*v
It is clear that the pulse frequency is higher than the wind speed signal. In practical applications, the average value is dozens, and the sensitivity of the wind speed - frequency converter can be increased by adjusting the distance between the axis and the centre of the wind cup。
Ii: frequency - voltage conversion circuits
Wind speed sensors function to convert wind speed signals to voltage signal output. So the pulse signal output from the pv switch tube has to be converted into a voltage signal through the f/v converter. Lm2907 is a dedicated f/v transformation integrated circuit with high accuracy, low cost, etc., which allows for a high accuracy f/v transformation with only a small number of external components. The relationship between output voltage v1 and input pulse frequency is: vo=k*vcc*r2*c2*f
If an a/d converter is added to the output end of the f/v converter and the electrical circuit is displayed, it is convenient to form a wind schedule. This circuit, with minor modifications, can also be used as a speed sensor in the automatic retrenchment system, whose performance exceeds that of the speed generator。
The wind speed sensor's circuit appears to be complex and, in fact, it is well understood that the wind speed sensor's circuit provides us with a good idea of how it works, how it measures wind speed, which also changes the way it used to measure wind speed, making it safer and more accurate. It also gives us some insight into wind speed sensors and about how to use them in life to make them useful。
