Wide span thermal wind sensor system with dual chips

A novel thermal wind sensor system based on dual chips was presented in this paper. One chip is thermal anemometer, which operates in Constant Temperature Difference (CTD) mode, another is calorimetric wind sensor, which operates in Constant Power (CP) mode. Both chips are designed to work at the same time. In the low wind speed (from 0 to 10m/s for example), the CP mode chip can detect accurate wind velocity and direction with less temperature drift, which is used as a reference for calculating the offset voltage of the CTD mode chip caused by the variation of ambient temperature; meanwhile the data are also as the output of the system. So compared with single chip wind sensors, the dual chips wind system can detect both low and high wind speed with higher accuracy and less temperature drift. The testing results indicate that the accuracy of low wind speed under 10m/s is ±0.3m/s and that of high speed from 10m/s to 40m/s is ±0.6m/s, and the measurement span is above 40m/s. In this system, dual chips are designed to operate in two different modes and their outputs are detected by a Micro Controller Unit (MCU).

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