Research And Design On Device For Crop Pest Prevention Through Acoustic Directional Technique Driven By Wind Power

Recently, a new method of crop pest prevention through resonant acoustic isattracting many people’s attention. Biological effect research shows that sound intensityand frequency are primary factors to effect the prevention of crop pests throughresonating acoustic technique. Furthermore, Long-term acoustic radiation will have aserious impact on humans and animals. Based on these, this paper using loudspeakerarray to radiate directional acoustic, it can not only accumulate acoustic energy andincrease sound intensity, but also can it prevent a certain range of crop pests.On the basis of theoretical deduction and positive study certified that loudspeakerarray can realize acoustic directional, this paper put forward a device for crop pestprevention through acoustic directional technique driven by wind power. On the onehand, wind turbine drive the device made loudspeaker generate changing acoustic signalwith the change of natural wind’s frequency, while acoustic signal bandwidth covers thecrop pests’ resonance frequency range. On the other hand, the customized voltage stabledesign guaranteed that acoustic amplitude controlled within a certain secure thresholdrange.In this paper, the main research work and achievements are as follows:①This paper did some comparative research on different structures acousticarray’s directional through the analysis of theory and simulation of Matlab afterdiscussing the theory of acoustic resonant technique and two ways(which are acousticparameter effects and interference effects) to realize acoustic directional.②Through Matlab simulation and directional experiment, this paper drew aconclusion that the number of acoustic sources, spacing among them and parameter awere the main factors to effect the directionality of y=a|x|array. Under the currentexperimental circumstance, the directivity experiment of y=a|x|array approved thefeasibility of prevention of crop pests through acoustic directional technique.③Through theory analysis and simulation of Orcad/Pspice, we concluded theloudspeaker’s impedance curve. Then, loudspeaker’s impedance curve was tested withthe method of constant current technique, it made the selection of loudspeaker whichhave the closest impedance curve become easier. Furthermore, we discussed someimpedance matching issues that were related to the paper.④Based on the latest technique about voltage regulation control system of loudspeaker array drive devices, this paper used the method of multi-tap winding toachieve voltage control. Then a mathematical model of the generator was stated fromthe theory. At last, this paper approved the feasibility of using the method of multi-tapwinding to achieve speaker array’s output of voltage basically stable from the static anddynamic aspects in the Matlab/simulink software.⑤Method of multi-tap winding to achieve voltage step adjustment was verifiedthrough static experiment. Then, circuit scheme was designed to achievegenerator voltage stable dynamically, including rectifier filter circuit, stabilized voltagesupply, voltage comparator and relay driving module.