【摘要】 作为变电站必不可少的电压冲击防护设备，避雷器的可靠性评估对于提高电力系统的稳定性至关重要，而避雷器老化试验耗时较长、失效数据较少等问题使得可靠性评估受到限制。针对试验耗时长的问题，文章设计并开展了阀片的加速老化试验，使用阿伦尼乌斯模型实现加速条件到正常条件下寿命数据的等效。针对失效数据少的问题，文章基于双参数和三参数威布尔分布模型，分别使用最小二乘法和灰色模型估计法对小样本数据进行可靠性建模，并分析不同参数和不同失效率估计公式对可靠性模型的影响。经验证明三参数威布尔分布模型拟合效果优于双参数，相关系数提高了0.026 8,失效率估计公式影响模型参数估计值和拟合效果，参数估计值差距可达1.312,相关系数差距可达0.018 3。文章通过调整模型参数和参数估计方法，实现了模型拟合效果的优化，为小样本数据下可靠性模型参数估计的精度提升提供了参考。更多还原

【Abstract】 As an essential component of voltage shock protection device in substations, the reliability of lightning arresters is crucial for enhancing the stability of power system, while the reliability evaluation is limited by problems such as long aging test time and scarce failure data. In view of the problem of long test time, the accelerated aging test of the valve plate is designed and carried out, and the Arrhenius model is used to achieve the equivalence of the life data from the accelerated conditions to the normal conditions. Aiming at the problem of less failure data, based on the two-parameter and three-parameter Weibull distribution models, the least squares method and the grey model estimation method are used to model the reliability of small sample data, and the influence of different failure rate estimation formulas on the reliability model is analyzed. It is verified that the fitting effect of the three-parameter Weibull distribution model is better than that of the two-parameter Weibull distribution model, the correlation coefficient is increased by 0.026 8. The failure rate estimation formula affects the parameters estimated value and fitting effect of the model, and the difference between the parameter estimates can reach 1.312 and the correlation coefficient gap can reach 0.018 3. This paper optimizes the fitting effect of the model by adjusting the model parameters and parameter estimation methods, providing a reference for improving the accuracy of reliability model parameter estimation under small sample data.更多还原