输电线路杆塔接地状态评估及风险分级研究

Research on Grounding State Estimation and Risk Classification of Transmission Line Towers

摘要:

提出了一种杆塔接地装置状态评估和风险分级的方法。该方法依据输电线路杆塔的接地参数——接地电阻测量值与接地电阻设计值，引入了中间参数——杆塔接地电阻与设计要求值的偏差率σ和接地电阻测量值变化率γ，借助于四分位数法的统计学方法，评估杆塔接地装置状态，将输电线路全线杆塔依据风险程度递进划分为ABCDE五个级别。在输电线路杆塔接地参数累积大量数据的前提下，基于最大期望算法（EM算法），预测杆塔接地参数随时间的分布规律，实现在杆塔接地参数测量之前，通过预测的参数来修正杆塔接地装置的风险分级。

Abstract:

A method for state estimation and risk classification of tower grounding devices is presented. Based on the grounding parameters of poles and towers in transmission line, that is, the measured value of grounding resistance and the design value of grounding resistance, the intermediate parameter is introduced, that is, σ (the deviation rate of grounding resistance of the tower from the design requirement) and γ (the rate of change of the measured value of grounding resistance). The statistical method with the aid of quartile method evaluates the status of tower grounding device, and divides the entire towers of transmission line into five levels of ABCDE according to the degree of risk. Under the premise of a large amount of data accumulated on tower grounding parameters of transmission line, and based on the maximum expectation (EM) algorithm, the distribution rule of tower grounding parameters with time is predicted, and the risk classification of tower grounding device is corrected by the predicted parameters before the measurement of tower grounding parameters.