Vibration Measurement of UHV transmission line shield ring based on image edge recognition

It is difficult to measure the vibration of UHV transmission lines shielding ring with traditional displacement sensors because of its installation position is high and far from the tower. In order to evaluate the vibration level of the shielding ring and eliminate the hidden danger of the transmission lines. This paper proposes a method to get the amplitude and frequency of the vibration by recognizing the local image of structure based on differential operator. The method obtains the displacement time history curve of the structure by the image edge recognition, extracts the vibration frequency by using signal analysis method, and calculates the vibration amplitude by establishing the relationship among the actual displacement of the structure, the size of the reference object and its image bases on the principle of camera imaging. The reliability of this method is verified by test in the laboratory. It is applied to analyze the field vibration video of the shielding ring, and the frequency and amplitude of the shielding ring are obtained. Modal test is performed, and its result is the same as that calculated by the proposed method, whose effectiveness is further verified.