The Key Technology Research Of Wind Speed Test System Based On Acoustic Parametric Array

In today’s era of technology,s rapid development and progress, wind has existed not only as a natural phenomenon, but also as a clean renewable energy, wind energy gets more and more attention of the world. Whether in science, or in industrial production, wind speed measurement has a large number of applications, particularly in the field of meteorology and wind power generation, wind speed measurement has a more important value. Dogvane are varied, and their measurement principle are also different. Ultrasonic wind speed testing technology which is the most advanced currently, although overcomes the shortcomings of traditional measurement methods,can not achieve the speed test of large spatial extent, which limits the applications of the wind. For acoustic parametric array can produce unique low-frequency sound waves of high point, and can propagate long distance, this thesis proposes the use of transit-time measurement principle to establish the wind speed test system based on acoustic parametric array, and develop a new method to achieve long-distance and large-space wind speed test.Firstly, in this thesis, the acoustic parametric array of works carried out in detail, its directivity in the air for MATLAB simulation analysis, in order to give a theoretical basis and the feasibility of acoustic parametric array wind speed testing. Acoustic and ultrasonic parametric array comparative analysis of propagation in the air, in order to verify that the acoustic parametric array measuring wind speed speed test method can be realized within the large spatial extent. Transit-time method for the measurement principle explained in detail, in order to obtain the key factor affecting the accuracy of the wind speed test.Secondly, in this thesis, several cross-correlation time delay estimation algorithms are made to do the the MATLAB simulation analysis, through analysis and comparison of the simulation results, selecting the highest precision algorithm. In order to obtain the ideal acoustic parametric array signal thereby improving the measurement accuracy of the wind speed test system, making several kinds of acoustic parametric array preprocessing algorithm do the MATLAB simulation and analysing their influence to the wind speed measurement accuracy.Once more, in this thesis, designing the whole system,s wind sensor module whosefunction is that transmitting and receiving acoustic parametric array signal, then using the wind speed information carried in the received audio signal to realize the wind speed and direction measurement. Wind measuring probe consists of acoustic parametric array transmitting array and audio signal receiving array, transmitting array is implemented by ultrasonic transducers, receiving array is implemented by microphones.Finally, in this thesis, according to the theory and the analysis of simulation results,the system’s hardware circuit and software is carried on the detailed design respectively,using BF533 and STM32 to complete the design and implementation of the whole wind speed test system based on acoustic parametric array. On DSP platform realizing the modulation algorithm of acoustic parametric array and time delay estimation algorithm, and then calculating the wind speed and direction, on the STM32 platform realizing the LCD display of the measured data. At the same time, setting up relevant experimental test platform to debug and improve the system.