基于LM法参数估计的继电保护装置可靠性分析

Reliability Analysis for Relay Protection Devices Based on LM Parameter Estimation

分析保护装置的可靠性和准确预测继电保护装置的有效寿命,是保障智能变电站安全稳定运行的关键。分析了继电保护装置可靠性的相关概念,从失效机理方面着手,通过建立基于阿瑞尼尔斯(Arrhenius)模型和威布尔(Weibull)分布的联合老化失效模型,并基于电网的继电保护装置统计数据,利用LM法对联合失效率模型的参数进行估计,得到具体的设备老化失效率模型,进而确定保护装置的可靠性和有效使用寿命。算例分析结果表明,能科学预测保护装置的故障概率和有效寿命,可为智能变电站继电保护装置的状态检修工作提供指导依据。

Analysis of the reliability of protection devices and accurate estimation of their effective lifetime is the key to ensuring safe and stable operation of intelligent substations. Some concepts relating to the reliability of relay protection devices were analyzed. Starting from analysis of failure mechanism, through establishment of a united ageing failure model based on the Arrhenius model and Weibull distribution, and based on statistical data about grid relay protection devices, the parameters of the united failure rate model were estimated in the LM method, and a specific equipment aging failure rate model was obtained. Then, the reliability and effective lifetime of the protection device were determined. Case analysis results showed that the proposed method could accomplish a scientific prediction of the failure probability and effective lifetime of the protection device, thus providing guidance for the state maintenance of relay protection devices at intelligent substations.