Research on Evaluation Method and Application of Grounding State of Transmission Tower

In order to further improve the efficiency of operation and maintenance of transmission line tower grounding, this paper proposes a method of status assessment and risk classification of tower grounding devices. This method designs the deviation rate of the required value according to the measured value of the grounding resistance of the transmission line tower $\sigma$ Change rate of measured value of grounding resistance $\gamma$, based on the statistical method of quartile method, the status of tower grounding device is evaluated, and the whole transmission line tower is divided into five levels of ABCDE according to the risk degree. On the premise of accumulating a large amount of data on the transmission line tower grounding parameters, the maximum expectation algorithm (EM algorithm) is used to predict the distribution law of tower grounding parameters over time, so as to correct the risk classification of tower grounding devices through the predicted parameters before the measurement of tower grounding parameters.