继电保护的目的是保证电网的安全稳定运行，而不同的保护配置方案对电网的影响并不相同。分析了造成保护失效的不同原因，建立了用于评价不同方案的继电保护可靠性的马尔科夫模型，并运用状态空间法对其可靠性进行了分析。在此基础上，进一步分析了成本、故障损失等经济性因素的影响，研究了选择不同配置方案的效果，为实际保护配置方案的分析、评价提供了参考。

The objective of relay protection can ensure the safe and stable operation of power grid as far as possible, and the protection configuration schemes have different influence on power grids. This paper analyzed the reasons of protection failure, established the Markov model for the evaluation of relay protection reliability in different schemes and studied its reliability by using state space method. On the basis of the researcher results, this paper further investigated the influence of economic factors, such as cost, fault loss and so on, which could more comprehensively reflect the different effect of configuration schemes and provide references for the analysis and evaluation of protection configuration schemes in practice.