In view of the shortcomings of the current Medium Voltage Vacuum Circuit Breaker evaluation

such ashigh ambiguity and poor confidence

this paper proposes a grey cloud-fuzzy entropy evaluation model for the operat-ing state of the circuit breaker by using the relative entropy combination weighting idea. The model uses the intuition-istic hierarchical fuzzy analysis method to determine the subjective weight of the judgment output. The cross-entropymethod based on the analysis of the information difference is used to obtain the objective weight

and the relative en-tropy is used to obtain the optimal combination weight. At the same time

the cloud model is used to improve the graywhitening weight function. The fuzzy entropy theory is introduced to characterize the complex uncertainty of evalua-tion and as an auxiliary measure. The example analysis shows that the method is feasible and effective

and providesa feasible way for the circuit breaker state assessment research.