Design And Implementation Of Non-Stationary Wind Speed Measurement System

Wind is one of the most common natural phenomena,and wind speed is also an extremely important meteorological parameter.Especially in the field of navigation,sea surface wind speed is an important parameter to observe the changes of marine meteorology.At present,the commonly used wind speed measuring devices in the market mainly measure the wind speed in the land environment.When the anemometer works in the marine environment,such as installed on the marine buoy and ship,the current wind speed measuring devices in the market do not take into account the impact of the marine environment and equipment in the non-stationary state on the wind speed measurement accuracy.Aiming at this scene,this paper designs an ultrasonic anemometer,which is designed in three aspects: miniaturization,low power consumption and tilt angle compensation.Firstly,the preliminary model of the anemometer is established by using COMSOL software,and the wind field around the model is numerically simulated.The feasibility of the anemometer structure is confirmed and the size is optimized.The influence of the transducer spacing on the wind field is studied.Then a simple model is made to verify the simulation results,the appropriate transducer spacing is selected to reduce the volume of the anemometer,and the final three-dimensional model of the anemometer is designed.The relationship between the change of wind direction angle and the measurement error of wind speed is analyzed and studied.The fitting curve between the error and wind direction angle is obtained by the least square method,so as to compensate the measurement error caused by miniaturization design.After testing,the average error within the wind speed range of 0 ～ 20m/s after compensation is less than 0.3m/s.Secondly,the hardware circuit of anemometer is designed,including microprocessor circuit,ultrasonic transducer driving circuit,signal processing circuit,inertial measurement unit circuit,etc.the main power consumption sources of hardware circuit are analyzed,and the influence of square wave generation circuit on power consumption and the application of microprocessor low-power mode are studied.After testing,the power consumption of the anemometer in the working mode is about 0.88 W,the power consumption in the sleep mode is about 0.51 w,and the average power consumption is about 0.63wFinally,when the anemometer is installed on the ocean buoy or ship hull,due to the influence of waves,storms and other factors,the anemometer will tilt with the carrier.Aiming at this problem,a measurement platform is built to measure the wind speed data under different wind direction angles and tilt angles.Through the statistical analysis of the experimental data,the compensation algorithm based on multivariable nonlinear fitting and Gaussian fitting is used to compensate the part with large error.After testing,the maximum average error after compensation is 0.28m/s when the wind speed is 10m/s and 0.2m/s when the wind speed is 15m/s.