Study On Three-dimensional Ultrasonic Wind Speed And Direction Measurement Technology

As is known to all,wind is a very common natural phenomenon,and wind speed and direction are also very important meteorological parameters.The measurement of wind speed and direction is of great significance to navigation,aviation,scientific research,wind power generation and industrial and agricultural production.Traditional mechanical wind instruments are difficult to satisfy the requirement for the measurement of wind speed and direction in a broad range of areas,with the rapid development of micro-electronics technology and the improvement of software algorithm,makes the time accuracy of measurement and computer processing ability can be greatly increased,the ultrasonic sonde of the wind equipment such as high precision,compared with the traditional wind equipment without mechanical wear,high precision,to adapt to more complicated work environment.But through the literature and research found that ultrasonic wind industry both at home and abroad,and studies abroad for ultrasonic wind technology than domestic,and related ultrasonic wind products abroad than domestic manufacturers of similar products to be more perfect and mature,measuring accuracy is higher,for ultrasonic wind technology research has important practical significance and engineering application value.Aiming at the existing problems,a three-dimensional ultrasonic wind speed and direction measurement system based on high precision time digital converter TDC-GP22 was developed in this paper.Firstly,various ultrasonic wind measurement methods are introduced in detail in this paper and the time difference method is selected as the ultrasonic wind measurement method,and the three-dimensional orthogonal wind measurement array is used as the system wind measurement scheme.The whole system is divided into two parts: hardware and software.TDC-GP22,a high precision time digital converter from ACAM,is used to measure the ultrasonic transit time,and the accuracy can reach 22 ps in single-channel four-precision mode.Intermediate frequency transformer is used to build a amplifier circuit to drive the transducer.The 3.0V square wave pulse signal of TDC-GP22 is amplified into a pulse of about 100 V,and the high frequency vibration of the transducer is driven to send out ultrasonic waves.The echo signal conditioning circuit is designed with low noise and high bandwidth operational amplifier,including two-stage amplifying circuit and fourth-stage negative feedback Butterworth band-pass filter.CD4097 multiplexer was used to build the sound channel switching circuit,and the square wave signals were multiplexed to different transmitting circuits,and the echo signals generated by multiple transducers were connected to the signal conditioning circuit for amplification and filtering processing in time sharing.And the minimum system,three axis magnetic field sensor peripheral circuit,two axis tilt sensor module,communication interface circuit,etc.The program design mainly includes the main program,the chip driver of each measurement module,the serial port interrupt service function,the time measurement,the calculation of wind speed and direction and the switching switch control module.After completing the design of hardware and software and the installation of the whole system,the wind measuring platform was built for the experiment and calibration of the system,and the error analysis and calibration of the experimental data were carried out.Finally,the topic was summarized and prospected.