An investigation to the design of high-precision wind sensing device based on piezoelectric array

Abstract

A new wind sensing device based on bimorphs array is designed for apperceiving wind direction and velocity, whose structure is an L-shaped cantilevers array. A coupling model of the array is proposed to predict the response voltage stimulated by wind. By extracting the response voltage ( $U_m$ ) on each bimorph cantilever, the values of wind direction ( ${\alpha }_{n,\mathrm{cal}}$ ) and velocity ( $v_{n,\mathrm{cal}}$ ) can be calculated in terms of the geometric relation. Further, the relations among wind errors, array amounts (m) and array radius (r) are acquired, and m & r can be utilized to decreasing angle error $\left(\overline{E_{{\alpha }_n}}\right)$ and velocity error $\left(\overline{E_{v_n}}\right)$ of wind. The calculated and experimental results show that, increasing m initially yields decreasing these two errors, then it begins to increase the errors when m is larger than 6. The minimal wind angle and velocity errors of the array are 0.14° and 0.34%, respectively, at actual wind of 13.4 m/s, m = 6 and r = 20 mm. Meanwhile, increasing r can decrease $\overline{E_{v_n}}$ and $\overline{E_{{\alpha }_n}}$ , Besides, for calculating 20 random incidence wind angles, respectively, the range of wind velocity error is from 0.34% to 0.87%, the range of wind angle error is from 0.12°to 0.38°, and the response time is 10 ms.