基于二次相关的超声波风速风向测量方法

为解决超声波测风仪存在的抑制噪声能力不足、受环境温湿度等影响导致稳定性差等问题，提出一种基于二次相关算法的三阵元超声波测风方法。首先结合超声波测风原理设计了一种三阵元测风结构，该结构包含3个收发一体式超声波换能器；其次依据该系统结构给出一种基于二次相关的超声波传播时间测量方法，利用二次相关算法对噪声抑制更强的性能可有效提高风速风向测量的精度，并从理论上说明了所提测风方法不受超声波本身传播速度即环境温湿度对其的影响。最后通过模拟仿真实验和搭建的实际测量系统对所提方法进行了有效性验证。在实际测量中风速风向角的最大测量误差分别为2.0%和2.1°,基本达到了超声波风速风向测量的精度要求。

Ultrasonic wind speed and direction measurement method based on quadratic correlation

To solve the problems of insufficient noise suppression ability and poor stability caused by the influence of environmental temperature and humidity, etc, a three-array ultrasonic wind measurement method based on the quadratic correlation algorithm is proposed. Firstly, a three-array wind measurement structure is designed by combining the principle of ultrasonic wind measurement, which consists of three transmitting and receiving integrated ultrasonic sensors. Secondly, a method for measuring ultrasonic propagation time based on quadratic correlation is given according to the structure of the system, which can effectively improve the accuracy of wind speed and direction measurement by using stronger performance of the quadratic correlation algorithm for noise suppression. It is theoretically explained that the proposed wind measurement method is not affected by the propagation speed of the ultrasonic wave itself ( i. e. , the environmental temperature and humidity). Finally, the effectiveness of the proposed method is verified by simulation experiments and a real measurement system is established. The practical test shows that the maximum relative error of wind speed measurement is 2. 0% , and the maximum error of wind direction angle measurement is 2. 1°. Results basically meet the accuracy requirements of ultrasonic wind speed and direction measurement.