Analysis Of The Influence Of Lightning Arrester Action On The Identification Of Lightning Strikes On 110kV Double-circuit Lines On The Same Tower

With the continuous development of society,the scale and structure of transmission network are becoming more and more complex,the number of transmission lines is increasing and the corridor resources are becoming increasingly tense.Hence,common-tower multiple line,which are conducive to ease the transmission line corridors,emerge as the times require,and have been widely used in electric power today,especially double-circuit transmission lines on the same tower.However,the double circuit is liable to be struck by lightning relative to the single back.In common use of lightning protection measures,lightning protection measures with frequent lightning,high soil resistivity and complex terrain are not effective.Therefore,the installation of line lightning arresters is mainly used to protect such transmission lines.In this paper,for the 110 kV double-circuit line on the same tower,from the perspective of the lightning arrester installed on the line,the phase-to-mode conversion is performed on the double-circuit line on the same tower.The converted common-vector and anti-velocity modules are used to separate the conductor from the single-phase ground fault,the lightning winding wire and the lightning arrester line.By summarizing its characteristics,it is concluded that the operation of the arrester on the line will cause a certain impact on the lightning strike on the circuit.The overall performance is that the amplitude of the traveling wave head is reduced,and the shielding failure is characterized by the turning point of the initial traveling wave's falling edge and subsequent oscillation.But,if there is no failure on the shielding,the overall performance is that there is a clear catadioptric process at the falling edge of the initial traveling wave,and the subsequent lightning wave at the installation point of the lightning arrester shows the same polarity wave head.These characteristics make it difficult to identify the wave head with single-end ranging.Considering that the arrester is installed on the line,for the single-phase grounding fault and the lightning strike fault,the least squares linear fitting of the initial zero-mode current falling edge waveform of the traveling wave counter-vector and calculate its slope,which can realize the identification of the lightning strike fault and the single-phase earth fault.But for the characteristics of the influence of the action of the lightning arrester on the lightning strike,The fractal dimension of the traveling wave in the fixed time window which can reflect the action characteristics of the arrester is calculated by fractal box dimension.According to the difference of the fractal coefficient,the construction criterion can effectively identify the operation of the arrester,and provide basis for the maintenance and service life estimation of the arrester in the later period.