Application Of Spectrum Refinement In Vibration Detection Of Power Tower

In recent years,our country has invested more and more in the construction of electric transmission network,and the electric power tower is one of the most important components of the electric transmission network,so the safety of the electric power tower has been paid more and more attention by the government.However,due to the complicated working environment of the high-voltage electric power tower,there may be too many uncontrollable factors,and the accident of the collapse of the electric power tower caused by the weather has also occurred frequently,which further threatens the personal safety of the electric power tower inspector.In this context,both studying the safety monitoring of electric power tower and processing with analysis of their vibration signals are very important.This paper takes the electric power tower as the research object.Firstly,the research status of electric power tower safety monitoring,the research status of PSD(Position Sensitive Detector)and spectrum refinement technology are all introduced.The non-contact measurement method(using PSD)is used to collect the vibration signal of electric power tower.Secondly,the FFT algorithm and three kinds of spectrum thinning algorithms are introduced: ZFFT(Zoom-FFT)algorithm,FFT-FS(Fast Fourier Transform-Fourier series)algorithm and CZT(Chirp Z-transform)algorithm.To compare from applicable occasions and computational complexity,we conclude that the CZT algorithm is more suitable in this system.Because the interference of external conditions will affect the working state of the electric power tower,this paper collects the vibration signal of the electric power tower without interference,and uses MATLAB software to transform the signal into time-frequency and refine the spectrum to obtain the natural frequency diagram of the electric power tower.Then,by striking the electric power tower to simulate the external interference,the vibration signal generated during the tapping is processed,and the spectrum diagram of the signal under the interference condition is obtained.After comparing the spectrogram with its natural frequency diagram,it is found that the frequency domain characteristics of the electric power tower will be greatly affected under the external interference conditions,and the amplitude of the natural frequency will change greatly.This study provides a basis for fault signal warning of electric power tower and verifies the feasibility of CZT algorithm in this system.At the end of the paper,the workflow and hardware of the system are introduced.A set of hardware system including STM32F103 Enhanced microcontroller as CPU in signal processing system,semiconductor laser as light source,PSD as signal receiving terminal,power module including AMS1117 chip,OPA37 amplifier circuit and AD7888 analog-to-digital conversion circuit as signal processing module are established.