Routine tests in a preventive maintenance plan detect hidden failures and prevent mal-functions. The use of probabilistic models based on Markov chains is conventional in the reliability studies. The well-known models include both states of power system and protection system. This technique increases the complexity of model and study. In this letter, a state-of-the-art Markov model for analysis of the protective relays' reliability is assessed and an improved model is proposed. The power system states are removed from the model and instead the interactions of two systems are considered in the transition rates and costs. The proposed probabilistic model of numerical relays is used to optimize the cost of maintenance considering the back-up protection and uncertainties.

中文翻译：

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基于改进马尔可夫模型的继电保护可靠性分析与维护优化


预防性维护计划中的例行测试可以检测隐藏的故障并防止故障。基于马尔可夫链的概率模型的使用在可靠性研究中是常规的。众所周知的模型包括电力系统和保护系统的状态。该技术增加了模型和研究的复杂性。在这封信中，评估了用于分析保护继电器可靠性的最先进的马尔可夫模型，并提出了改进的模型。电力系统状态从模型中删除，而是在转换率和成本中考虑两个系统的相互作用。所提出的数字继电器概率模型用于考虑后备保护和不确定性来优化维护成本。