【摘要】 叙述了超声波风速测量的原理,依据时差法的理论推导了V型结构的二维超声波测风速的计算公式,提出了一种基于微控制器STM32的超声波风速仪的设计方法。描述了超声波发射LC振荡选频电路、信号放大电路、二阶有源低通滤波器和有源全波整流滤波的关键技术的实现过程,并给出相应电路图和验证结果,程序融入了AR自回归模型滤波算法。同时对温度对风速影响和脉动风场进行研究。实验结果表明:该电路动态自适应能力强,抗干扰能力较强,配以智能化算法可实现高精度的风速测量,具有较高的参考和实用价值。更多还原

【Abstract】 The measuring principle of ultrasonic anemometer was described in this paper. The calculation formula of v-shaped structure two-dimensional ultrasonic anemometer was deduced based on time difference method. The design method of the ultrasonic anemometer was put forward based on the STM32 microcontroller. The key technology in the implementation process about the ultrasonic launching LC oscillation frequency selective circuit,signal amplification circuit,second-order active low-pass filter,and active full-wave rectifier filter was described. And the corresponding circuit diagram and the verification results were given. The AR autoregressive model filter algorithm was embedded in the program. Meanwhile,the impact of the temperature on the wind speed and the fluctuating wind field were researched. The experimental results show that the circuit dynamic adaptive ability and anti-interference ability are excellent. The two-dimensional ultrasonic anemometer with intelligent algorithm can achieve high precision measurement of wind speed,which has high reference and practical value.更多还原