Research On Ultrasonic Wind Measurement System Based On Improved Time Difference Method

Accurate measurement of wind speed and direction is widely used in navigation,construction,environmental monitoring,agricultural production,wind power generation,weather forecasting and scientific research.Ultrasonic wind measurement is a new type of wind speed measurement.It is the premise of market application of ultrasonic wind measurement to study the system error and measurement error of ultrasonic wind measurement instrument,analyze the causes of various errors,reduce measurement error,improve measurement accuracy and make the wind measurement instrument meet the actual measurement requirements.At present,ultrasonic wind measuring instruments are different in frequency,voltage,power and array structure.The measured wind speed range,precision,accuracy is also different.The traditional ultrasonic wind detector has many disadvantages in extreme environment due to its own structure.The ultrasonic probe blocks the forward route of the wind,and then produces a shadow area behind the probe.The turbulence area in front of the probe affects the accuracy of wind speed measurement.In order to make up for the error of shadow effect,the single-path wind speed compensation algorithm is fitted on the basis of the moveout method,and the ultrasonic wind speed Angle compensation formula is derived through the single-path wind speed compensation formula,and the shadow effect compensation algorithm of the orthogonal array model is obtained.The original data and shadow effect compensation formula are used to fit.It was observed that the wind speed Angle compensation function fitted well with the measured value,and the compensated wind speed error decreased from 14.65% to 1.74%.The measurement accuracy of wind speed and direction has been improved.In addition,it is difficult to get the correct delay data when the hardware system makes ultrasonic delay measurement.Observe the ultrasonic echo signal under different wind speed and different starting signals.The relationship between echo signal,drive signal and wind speed is studied.Dynamic regulation of the driving signal voltage and the number of driving pulses to ensure the stability of the echo signal.The echo detection threshold is dynamically adjusted by using the echo detection chip GP22 to ensure the first wave detection of echosignal and the accuracy of delay data.In this paper,a new shadow effect compensation algorithm is proposed based on the improved time difference method.In addition,a new wind speed measurement system is designed by dynamically adjusting the driving signal to keep the echo signal stable when using the time difference method for time delay measurement.