Design And Realization Of Low Frequency Vibration Acquisition And Analysis Instrument

With the increasing demand for power resources from production and living,the security and stability of power transmission are particularly important.As the most important part of the power transmission process,the high voltage transmission tower line system is directly related to the safe transmission of power resources,and because of the natural factors that affect the safe operation of the transmission tower lines,mainly earthquakes,strong winds,and ice.Therefore,it is necessary to take certain anti-vibration measures for the transmission tower line system.The collection of wind speed and direction data of the transmission tower line system and the corresponding amplitude data of the transmission tower line can realize real-time monitoring of wind speed and direction of the transmission tower and prediction of wind speed of the transmission tower line system.In addition,the wind speed data can be combined with the finite element structural model of the transmission tower line,then the time-domain analysis and frequency domain analysis of the wind-induced vibration response of the transmission tower line system can be done under Davenport wind spectrum.In view of this,after studying the development status of ultrasonic anemometer,combined with ultrasonic wind measurement technology,embedded technology and digital signal processing technology,this paper designs and implements a low-frequency vibration acquisition analyzer based on ARM processor.Firstly,the data acquisition terminal of the low-frequency vibration acquisition analyzer is designed based on ARM processor and FPGA processor.The terminal's hardware circuit design mainly includes data sampling module,operation and control module,and communication module.The software design mainly includes FPGA software workflow design and CPU software architecture design.Secondly,in order to improve the accuracy of wind speed measurement,Wiener filtering is used to filter the ultrasonic frequency wind direction sensor noise,and then the Hilbert transform is used to envelope the ultrasonic echo signal.The wavelet transform is used for the envelope signal to perform time domain summation.Localized analysis in the frequency domain realizes the detection of the time point of ultrasonic signal reception,and finally obtains a corresponding high precision wind speed value.Then,a wind speed forecasting model was established using time series analysis,the wind speed measured data was compared with the wind speed data of the forecasting model to find that there was a large error in wind speed forecasting.To solve this problem,the iterative characteristics of Kalman filter are used to combine the time series analysis method with the Kalman filter algorithm to obtain a new wind speed prediction model.The wind speed measured data is compared with the new wind speed prediction model prediction data and it is found that the hybrid algorithm can be significant improve wind speed forecasting accuracy.Finally,the wind-induced vibration response of the transmission tower line system is analyzed in time domain and frequency domain based on the Davenport wind speed spectrum,and the power spectrum of the transmission tower is obtained.The low-frequency vibration analyzer has been built and tested on the platform,the results show that the analyzer can accurately capture and accurately calculate the wind speed,direction signal and displacement signal,prove the reliability of the analyzer.At present,the low-frequency vibration acquisition analyzer has passed the acceptance audit of the Guangdong Electric Power Research Institute,and will soon be put into practical use to safeguard the safe transmission of electric power resources.