Intelligent substation protection system reliability stratified equivalent method

The invention discloses an intelligent substation protection system reliability stratified equivalent method applied to an intelligent substation protection system. The method is characterized by including 1, performing subsystem division on the intelligent substation protection system; 2, performing reliability computation on the subsystems; 3, combining combined unit subsystems with an intelligent terminal subsystem; 4, combining a protecting device subsystem with an auxiliary device subsystem; 5, combining two combined systems; 6, combining the combined system with an exchanger subsystem; 7, completing the intelligent substation protection system reliability stratified equivalent method. The scale of an intelligent substation protection system entire reliability model can be reduced, computation can be simplified, the probability of curse of dimensionality is reduced, the intelligent substation protection system internal equipment structure relationships can be described more clearly and completely, and the method is convenient to promote and apply to a more complex intelligent substation protection system.