Reliability of modular multilevel converter(MMC)is related to the reliable and stable operation of HVDC system. First
based on the analysis of MMC single SM reliability model
the scenario related to the submodule(SM)reliability is generated by using Latin Hypercube Sampling(LHS)and Cholesky decomposition sorting. Then
the correlation coefficients of three kinds of Copula functions are obtained by using the maximum likelihood estimation theory(MLE)on the basis of generating SM correlation scenario
and the shortest Euclidean distance is used to select the optimal Copula function. After that
the MMC reliability analysis model considering the SM correlation is set up. Finally
the Shanghai Nanhui project is taken as an example to verify that the proposed method can meet the MMC reliability analysis requirements.